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Kaushik S, Ödén J, Sharma DS, Fredriksson A, Toma-Dasu I. Generation and evaluation of anatomy-preserving virtual CT for online adaptive proton therapy. Med Phys 2024; 51:1536-1546. [PMID: 38230803 DOI: 10.1002/mp.16941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 11/24/2023] [Accepted: 12/31/2023] [Indexed: 01/18/2024] Open
Abstract
BACKGROUND Daily CTs generated by CBCT correction are required for daily replanning in online-adaptive proton therapy (APT) to effectively deal with inter-fractional changes. Out of the currently available methods, the suitability of a daily CT generation method for proton dose calculation also depends on the anatomical site. PURPOSE We propose an anatomy-preserving virtual CT (APvCT) method as a hybrid method of CBCT correction, which is especially suitable for large anatomy deformations. The accuracy of the hybrid method was assessed by comparison with the corrected CBCT (cCBCT) and virtual CT (vCT) methods in the context of online APT. METHODS Seventy-one daily CBCTs of four prostate cancer patients treated with intensity modulated proton therapy (IMPT) were converted to daily CTs using cCBCT, vCT, and the newly proposed APvCT method. In APvCT, planning CT (pCT) were mapped to CBCT geometry using deformable image registration with boundary conditions on controlling regions of interest (ROIs) created with deep learning segmentation on cCBCT. The relative frequency distribution (RFD) of HU, mass density and stopping power ratio (SPR) values were assessed and compared with the pCT. The ROIs in the APvCT and vCT were compared with cCBCT in terms of Dice similarity coefficient (DSC) and mean distance-to-agreement (mDTA). For each patient, a robustly optimized IMPT plan was created on the pCT and subsequent daily adaptive plans on daily CTs. For dose distribution comparison on the same anatomy, the daily adaptive plans on cCBCT and vCT were recalculated on the corresponding APvCT. The dose distributions were compared in terms of isodose volumes and 3D global gamma-index passing rate (GPR) at γ(2%, 2 mm) criterion. RESULTS For all patients, no noticeable difference in RFDs was observed amongst APvCT, vCT, and pCT except in cCBCT, which showed a noticeable difference. The minimum DSC value was 0.96 and 0.39 for contours in APvCT and vCT respectively. The average value of mDTA for APvCT was 0.01 cm for clinical target volume and ≤0.01 cm for organs at risk, which increased to 0.18 cm and ≤0.52 cm for vCT. The mean GPR value was 90.9%, 64.5%, and 67.0% for APvCT versus cCBCT, vCT versus cCBCT, and APvCT versus vCT, respectively. When recalculated on APvCT, the adaptive cCBCT and vCT plans resulted in mean GPRs of 89.5 ± 5.1% and 65.9 ± 19.1%, respectively. The mean DSC values for 80.0%, 90.0%, 95.0%, 98.0%, and 100.0% isodose volumes were 0.97, 0.97, 0.97, 0.95, and 0.91 for recalculated cCBCT plans, and 0.89, 0.88, 0.87, 0.85, and 0.81 for recalculated vCT plans. Hausdorff distance for the 100.0% isodose volume in some cases of recalculated cCBCT plans on APvCT exceeded 1.00 cm. CONCLUSIONS APvCT contours showed good agreement with reference contours of cCBCT which indicates anatomy preservation in APvCT. A vCT with erroneous anatomy can result in an incorrect adaptive plan. Further, slightly lower values of GPR between the APvCT and cCBCT-based adaptive plans can be explained by the difference in the cCBCT's SPR RFD from the pCT.
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Affiliation(s)
- Suryakant Kaushik
- RaySearch Laboratories AB (Publ), Stockholm, Sweden
- Department of Physics, Medical Radiation Physics, Stockholm University, Stockholm, Sweden
- Department of Oncology and Pathology, Medical Radiation Physics, Karolinska Institutet, Stockholm, Sweden
| | - Jakob Ödén
- RaySearch Laboratories AB (Publ), Stockholm, Sweden
| | | | | | - Iuliana Toma-Dasu
- Department of Physics, Medical Radiation Physics, Stockholm University, Stockholm, Sweden
- Department of Oncology and Pathology, Medical Radiation Physics, Karolinska Institutet, Stockholm, Sweden
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Shinde P, Jadhav A, Shankar V, Dhoble SJ. Evaluation of the dosimetric influence of interfractional 6D setup error in hypofractionated prostate cancer treated with IMRT and VMAT using daily kV-CBCT. J Med Imaging Radiat Sci 2022; 53:693-703. [PMID: 36289030 DOI: 10.1016/j.jmir.2022.09.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 09/01/2022] [Accepted: 09/29/2022] [Indexed: 11/06/2022]
Abstract
INTRODUCTION Prostate cancer is one of the most common malignant tumors in men and is usually treated with advanced intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT). Significant uncorrected interfractional 6-Dimensional setup errors could impact the delivered dose. The aim of this study was to assess the dosimetric impact of 6D interfractional setup errors in hypofractionated prostate cancer using daily kilovoltage cone-beam computed tomography (kV-CBCT). METHODS This retrospective study comprised twenty prostate cancer patients treated with hypofractionated IMRT (8) and VMAT (12) with daily kV-CBCT image guidance. Interfraction 6D setup errors along lateral, longitudinal, vertical, pitch, roll, and yaw axes were evaluated for 400 CBCTs. For targets and organs at risk (OARs), the dosimetric impact of rotational error (RError), translational error (TError), and translational plus rotational error (T+RError) were evaluated on kV-CBCT images. RESULTS The single fraction maximum TError ranged from 12-20 mm, and the RError ranged from 2.80-3.00. The maximum mean absolute dose variation ΔD in D98% (dose to 98% volume) of CTV-55 and PTV-55 was -0.66±0.82 and -5.94±3.8 Gy, respectively, in the T+RError. The maximum ΔD (%) for D98% and D0.035cc in CTV-55 was -4.29% and 2.49%, respectively, while in PTV-55 it was -24.9% and 2.36%. The mean dose reduction for D98% in CTV-55 and D98% and D95% in PTV-55 was statistically significant (p<0.05) for TError and T+RError. The mean dose variation for Dmean and D50% in the rectum was statistically significant (p<0.05) for TError and T+RError. CONCLUSION The uncorrected interfractional 6D setup error results in significant target underdosing and OAR overdosing in prostate cancer. This emphasizes the need to correct interfractional 6D setup errors daily in IMRT and VMAT.
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Affiliation(s)
| | - Anand Jadhav
- Department of Radiation Oncology, Sir H N Reliance Foundation Hospital and Research Centre, Mumbai, 400004, India
| | - V Shankar
- Department of Radiation Oncology, Apollo Cancer Center, Chennai, 600035, India
| | - S J Dhoble
- Department of Physics, R. T. M. Nagpur University, Nagpur, 440033, India
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Assessment of intrafractional prostate motion and its dosimetric impact in MRI-guided online adaptive radiotherapy with gating. Strahlenther Onkol 2022; 199:544-553. [PMID: 36151215 DOI: 10.1007/s00066-022-02005-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 09/04/2022] [Indexed: 10/14/2022]
Abstract
PURPOSE This study aimed to evaluate the intrafractional prostate motion captured during gated magnetic resonance imaging (MRI)-guided online adaptive radiotherapy for prostate cancer and analyze its impact on the delivered dose as well as the effect of gating. METHODS Sagittal 2D cine-MRI scans were acquired at 4 Hz during treatment at a ViewRay MRIdian (ViewRay Inc., Oakwood Village, OH, USA) MR linac. Prostate shifts in anterior-posterior (AP) and superior-inferior (SI) directions were extracted separately. Using the static dose cloud approximation, the planned fractional dose was shifted according to the 2D gated motion (residual motion in gating window) to estimate the delivered dose by superimposing and averaging the shifted dose volumes. The dose of a hypothetical non-gated delivery was reconstructed similarly using the non-gated motion. For the clinical target volume (CTV), rectum, and bladder, dose-volume histogram parameters of the planned and reconstructed doses were compared. RESULTS In total, 174 fractions (15.7 h of cine-MRI) from 10 patients were evaluated. The average (±1 σ) non-gated prostate motion was 0.6 ± 1.0 mm in the AP and 0.0 ± 0.6 mm in the SI direction with respect to the centroid position of the gating boundary. 95% of the shifts were within [-3.5, 2.7] mm in the AP and [-2.9, 3.2] mm in the SI direction. For the gated treatment and averaged over all fractions, CTV D98% decreased by less than 2% for all patients. The rectum and the bladder D2% increased by less than 3% and 0.5%, respectively. Doses reconstructed for gated and non-gated delivery were similar for most fractions. CONCLUSION A pipeline for extraction of prostate motion during gated MRI-guided radiotherapy based on 2D cine-MRI was implemented. The 2D motion data enabled an approximate estimation of the delivered dose. For the majority of fractions, the benefit of gating was negligible, and clinical dosimetric constraints were met, indicating safety of the currently adopted gated MRI-guided treatment workflow.
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Shinde P, Jadhav A, Gupta KK, Dhoble S. QUANTIFICATION OF 6D INTER-FRACTION TUMOUR LOCALISATION ERRORS IN TONGUE AND PROSTATE CANCER USING DAILY KV-CBCT FOR 1000 IMRT AND VMAT TREATMENT FRACTIONS. RADIATION PROTECTION DOSIMETRY 2022; 198:1265-1281. [PMID: 35870445 DOI: 10.1093/rpd/ncac145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 04/08/2022] [Accepted: 05/16/2022] [Indexed: 06/15/2023]
Abstract
This study aimed to evaluate the 6D inter-fraction tumour localisation errors in 20 tongue and 20 prostate cancer patients treated with intensity-modulated radiation therapy and volumetric-modulated arc therapy. The patient tumour localisation errors in lateral, longitudinal and vertical translation axes and pitch, roll and yaw rotational axes were analysed by automatic image registration of daily pretreatment kilovoltage cone-beam computed tomography (kV-CBCT) with planning CT in 1000 fractions. The overall mean error (M), systematic error (Σ), random error (σ) and planning target volume (PTV) margins were evaluated. The frequency distributions of setup errors were normally distributed about the mean except for pitch in the tongue and prostate. The overall 3D vector length ≥ 5 mm was 14.2 and 49.8% in the ca-tongue and ca-prostate, respectively. The frequency of rotational errors ≥1 degree was a maximum of 37 and 59.5%, respectively, in ca-tongue and ca-prostate. The M, Σ and σ for all translational and rotational axes decreased with increasing frequency of verification correction in ca-tongue and ca-prostate patients. Similarly, the PTV margin was reduced with no correction to alternate day correction from a maximum of 4.7 to 2.5 mm in ca-tongue and from a maximum of 8.6 to 4.7 mm in ca-prostate. The results emphasised the vital role of the higher frequency of kV-CBCT based setup correction in reducing M, Σ, σ and PTV margins in ca-tongue and ca-prostate patients.
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Affiliation(s)
- Prashantkumar Shinde
- Department of Physics, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440033, India
| | - Anand Jadhav
- Department of Radiation Oncology, Sir H N Reliance Foundation Hospital & Research Centre, Mumbai 400004, India
| | - Karan Kumar Gupta
- Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617, ROC
| | - Sanjay Dhoble
- Department of Physics, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440033, India
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Hewson EA, Nguyen DT, Le A, Booth JT, Keall PJ, Mejnertsen L. Optimising multi-target multileaf collimator tracking using real-time dose for locally advanced prostate cancer patients. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac8967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 08/12/2022] [Indexed: 11/11/2022]
Abstract
Abstract
Objective. The accuracy of radiotherapy for patients with locally advanced cancer is compromised by independent motion of multiple targets. To date, MLC tracking approaches have used 2D geometric optimisation where the MLC aperture shape is simply translated to correspond to the target’s motion, which results in sub-optimal delivered dose. To address this limitation, a dose-optimised multi-target MLC tracking method was developed and evaluated through simulated locally advanced prostate cancer treatments. Approach. A dose-optimised multi-target tracking algorithm that adapts the MLC aperture to minimise 3D dosimetric error was developed for moving prostate and static lymph node targets. A fast dose calculation algorithm accumulated the planned dose to the prostate and lymph node volumes during treatment in real time, and the MLC apertures were recalculated to minimise the difference between the delivered and planned dose with the included motion. Dose-optimised tracking was evaluated by simulating five locally advanced prostate plans and three prostate motion traces with a relative interfraction displacement. The same simulations were performed using geometric-optimised tracking and no tracking. The dose-optimised, geometric-optimised, and no tracking results were compared with the planned doses using a 2%/2 mm γ criterion. Main results. The mean dosimetric error was lowest for dose-optimised MLC tracking, with γ-failure rates of 12% ± 8.5% for the prostate and 2.2% ± 3.2% for the nodes. The γ-failure rates for geometric-optimised MLC tracking were 23% ± 12% for the prostate and 3.6% ± 2.5% for the nodes. When no tracking was used, the γ-failure rates were 37% ± 28% for the prostate and 24% ± 3.2% for the nodes. Significance. This study developed a dose-optimised multi-target MLC tracking method that minimises the difference between the planned and delivered doses in the presence of intrafraction motion. When applied to locally advanced prostate cancer, dose-optimised tracking showed smaller errors than geometric-optimised tracking and no tracking for both the prostate and nodes.
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Rusanov B, Hassan GM, Reynolds M, Sabet M, Kendrick J, Farzad PR, Ebert M. Deep learning methods for enhancing cone-beam CT image quality towards adaptive radiation therapy: A systematic review. Med Phys 2022; 49:6019-6054. [PMID: 35789489 PMCID: PMC9543319 DOI: 10.1002/mp.15840] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 05/21/2022] [Accepted: 06/16/2022] [Indexed: 11/11/2022] Open
Abstract
The use of deep learning (DL) to improve cone-beam CT (CBCT) image quality has gained popularity as computational resources and algorithmic sophistication have advanced in tandem. CBCT imaging has the potential to facilitate online adaptive radiation therapy (ART) by utilizing up-to-date patient anatomy to modify treatment parameters before irradiation. Poor CBCT image quality has been an impediment to realizing ART due to the increased scatter conditions inherent to cone-beam acquisitions. Given the recent interest in DL applications in radiation oncology, and specifically DL for CBCT correction, we provide a systematic theoretical and literature review for future stakeholders. The review encompasses DL approaches for synthetic CT generation, as well as projection domain methods employed in the CBCT correction literature. We review trends pertaining to publications from January 2018 to April 2022 and condense their major findings - with emphasis on study design and deep learning techniques. Clinically relevant endpoints relating to image quality and dosimetric accuracy are summarised, highlighting gaps in the literature. Finally, we make recommendations for both clinicians and DL practitioners based on literature trends and the current DL state of the art methods utilized in radiation oncology. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Branimir Rusanov
- School of Physics, Mathematics and Computing, The University of Western Australia, Perth, Western Australia, 6009, Australia.,Department of Radiation Oncology, Sir Chairles Gairdner Hospital, Perth, Western Australia, 6009, Australia
| | - Ghulam Mubashar Hassan
- School of Physics, Mathematics and Computing, The University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Mark Reynolds
- School of Physics, Mathematics and Computing, The University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Mahsheed Sabet
- School of Physics, Mathematics and Computing, The University of Western Australia, Perth, Western Australia, 6009, Australia.,Department of Radiation Oncology, Sir Chairles Gairdner Hospital, Perth, Western Australia, 6009, Australia
| | - Jake Kendrick
- School of Physics, Mathematics and Computing, The University of Western Australia, Perth, Western Australia, 6009, Australia.,Department of Radiation Oncology, Sir Chairles Gairdner Hospital, Perth, Western Australia, 6009, Australia
| | - Pejman Rowshan Farzad
- School of Physics, Mathematics and Computing, The University of Western Australia, Perth, Western Australia, 6009, Australia.,Department of Radiation Oncology, Sir Chairles Gairdner Hospital, Perth, Western Australia, 6009, Australia
| | - Martin Ebert
- School of Physics, Mathematics and Computing, The University of Western Australia, Perth, Western Australia, 6009, Australia.,Department of Radiation Oncology, Sir Chairles Gairdner Hospital, Perth, Western Australia, 6009, Australia
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Hewson EA, Dipuglia A, Kipritidis J, Ge Y, O'Brien R, Roderick S, Bell L, Poulsen PR, Eade T, Booth JT, Keall PJ, Nguyen DT. First experimental evaluation of multi-target multileaf collimator tracking during volumetric modulated arc therapy for locally advanced prostate cancer. Radiother Oncol 2021; 160:212-220. [PMID: 33971194 DOI: 10.1016/j.radonc.2021.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/27/2021] [Accepted: 05/02/2021] [Indexed: 01/24/2023]
Abstract
PURPOSE Locally advanced and oligometastatic cancer patients require radiotherapy treatment to multiple independently moving targets. There is no existing commercial solution that can simultaneously track and treat multiple targets. This study experimentally implemented and evaluated a real-time multi-target tracking system for locally advanced prostate cancer. METHODS Real-time multi-target MLC tracking was integrated with 3D x-ray image guidance on a standard linac. Three locally advanced prostate cancer treatment plans were delivered to a static lymph node phantom and dynamic prostate phantom that reproduced three prostate trajectories. Treatments were delivered using multi-target MLC tracking, single-target MLC tracking, and no tracking. Doses were measured using Gafchromic film placed in the dynamic and static phantoms. Dosimetric error was quantified by the 2%/2 mm gamma failure rate. Geometric error was evaluated as the misalignment between target and aperture positions. The multi-target tracking system latency was measured. RESULTS The mean (range) gamma failure rates for the prostate and lymph nodes, were 18.6% (5.2%, 28.5%) and 7.5% (1.1%, 13.7%) with multi-target tracking, 7.9% (0.7%, 15.4%) and 37.8% (18.0%, 57.9%) with single-target tracking, and 38.1% (0.6%, 75.3%) and 37.2% (29%, 45.3%) without tracking. Multi-target tracking had the lowest geometric error with means and standard deviations within 0.2 ± 1.5 for the prostate and 0.0 ± 0.3 mm for the lymph nodes. The latency was 730 ± 20 ms. CONCLUSION This study presented the first experimental implementation of multi-target tracking to independently track prostate and lymph node displacement during VMAT. Multi-target tracking reduced dosimetric and geometric errors compared to single-target tracking and no tracking.
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Affiliation(s)
- Emily A Hewson
- ACRF Image X Institute, University of Sydney School of Health Sciences, Sydney, Australia.
| | - Andrew Dipuglia
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia
| | - John Kipritidis
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia
| | - Yuanyuan Ge
- Nelune Comprehensive Cancer Centre, Prince of Wales Hospital, Sydney, Australia
| | - Ricky O'Brien
- ACRF Image X Institute, University of Sydney School of Health Sciences, Sydney, Australia
| | - Stephanie Roderick
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia
| | - Linda Bell
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia
| | - Per R Poulsen
- Department of Oncology and Danish Center for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
| | - Thomas Eade
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia
| | - Jeremy T Booth
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia; School of Physics, University of Sydney, Australia
| | - Paul J Keall
- ACRF Image X Institute, University of Sydney School of Health Sciences, Sydney, Australia
| | - Doan T Nguyen
- ACRF Image X Institute, University of Sydney School of Health Sciences, Sydney, Australia; Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia; School of Biomedical Engineering, University of Technology Sydney, Australia
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Koerber SA, Beuthien-Baumann B. [Modern radiation therapy planning and image-guided radiotherapy using the example of prostate cancer]. Radiologe 2021; 61:28-35. [PMID: 33057736 DOI: 10.1007/s00117-020-00763-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
CLINICAL/METHODICAL ISSUE Optimizing radiotherapy demands precise delineation of the target structure, not only before but also during the course of radiotherapy. STANDARD RADIOLOGICAL METHODS For many years, planning of external radiation treatment planning has been based on computer tomography data. METHODOLOGICAL INNOVATIONS With the advent of image-guided radiotherapy (IGRT), magnetic resonance imaging (MRI) and functional hybrid imaging are increasingly being integrated into radiation treatment planning. The development of the MR-linac can be seen as an innovation. PERFORMANCE The integration of MRI and hybrid imaging (positron emission tomography [PET]/CT, PET/MRI) in the treatment planning process enables more precise treatment planning due to the better morphological and functional information. The integration of MRI data on the MR-linac in daily position control enables adaptation of the irradiation plan to the current conditions. ACHIEVEMENTS Technical innovation such as the MR-linac as well as increasing use of hybrid imaging contribute to the objective of further individualization within (radio)oncology. PRACTICAL RECOMMENDATIONS Using the example of prostate cancer, the application of prostate-specific membrane antigen (PSMA) ligands and hybrid imaging offers great potential for individualized strategic treatment decisions. The MR-linac appears to be particularly suitable for radiation therapy of prostate cancer. Special attention must be paid to the technical aspects of positioning and data acquisition for the purpose of radiation treatment planning.
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Affiliation(s)
- Stefan A Koerber
- Klinik für Radioonkologie und Strahlentherapie, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Deutschland. .,Nationales Centrum für Tumorerkrankungen (NCT), Heidelberg, Deutschland. .,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Deutschland.
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Hewson EA, Ge Y, O'Brien R, Roderick S, Bell L, Poulsen PR, Eade T, Booth JT, Keall PJ, Nguyen DT. Adapting to the motion of multiple independent targets using multileaf collimator tracking for locally advanced prostate cancer: Proof of principle simulation study. Med Phys 2020; 48:114-124. [PMID: 33124079 DOI: 10.1002/mp.14572] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/21/2020] [Accepted: 10/23/2020] [Indexed: 01/22/2023] Open
Abstract
PURPOSE For patients with locally advanced cancer, multiple targets are treated simultaneously with radiotherapy. Differential motion between targets can compromise the treatment accuracy, yet there are currently no methods able to adapt to independent target motion. This study developed a multileaf collimator (MLC) tracking algorithm for differential motion adaptation and evaluated it in simulated treatments of locally advanced prostate cancer. METHODS A multi-target MLC tracking algorithm was developed that consisted of three steps: (a) dividing the MLC aperture into two possibly overlapping sections assigned to the prostate and lymph nodes, (b) calculating the ideally shaped MLC aperture as a union of the individually translated sections, and (c) fitting the MLC positions to the ideal aperture shape within the physical constraints of the MLC leaves. The multi-target tracking method was evaluated and compared with two existing motion management methods: single-target tracking and no tracking. Treatment simulations of six locally advanced prostate cancer patients with three prostate motion traces were performed for all three motion adaptation methods. The geometric error for each motion adaptation method was calculated using the area of overexposure and underexposure of each field. The dosimetric error was estimated by calculating the dose delivered to the prostate, lymph nodes, bladder, rectum, and small bowel using a motion-encoded dose reconstruction method. RESULTS Multi-target MLC tracking showed an average improvement in geometric error of 84% compared to single-target tracking, and 83% compared to no tracking. Multi-target tracking maintained dose coverage to the prostate clinical target volume (CTV) D98% and planning target volume (PTV) D95% to within 4.8% and 3.9% of the planned values, compared to 1.4% and 0.7% with single-target tracking, and 20.4% and 31.8% with no tracking. With multi-target tracking, the node CTV D95%, PTV D90%, and gross tumor volume (GTV) D95% were within 0.3%, 0.6%, and 0.3% of the planned values, compared to 9.1%, 11.2%, and 21.1% for single-target tracking, and 0.8%, 2.0%, and 3.2% with no tracking. The small bowel V57% was maintained within 0.2% to the plan using multi-target tracking, compared to 8% and 3.5% for single-target tracking and no tracking, respectively. Meanwhile, the bladder and rectum V50% increased by up to 13.6% and 5.2%, respectively, using multi-target tracking, compared to 2.7% and 1.9% for single-target tracking, and 11.2% and 11.5% for no tracking. CONCLUSIONS A multi-target tracking algorithm was developed and tracked the prostate and lymph nodes independently during simulated treatments. As the algorithm optimizes for target coverage, tracking both targets simultaneously may increase the dose delivered to the organs at risk.
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Affiliation(s)
- Emily A Hewson
- ACRF Image X Institute, University of Sydney Medical School, Sydney, NSW, Australia
| | - Yuanyuan Ge
- Nelune Comprehensive Cancer Centre, Prince of Wales Hospital, Sydney, NSW, Australia
| | - Ricky O'Brien
- ACRF Image X Institute, University of Sydney Medical School, Sydney, NSW, Australia
| | - Stephanie Roderick
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, NSW, Australia
| | - Linda Bell
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, NSW, Australia
| | - Per R Poulsen
- Department of Oncology and Danish Center for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
| | - Thomas Eade
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, NSW, Australia
| | - Jeremy T Booth
- Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, NSW, Australia.,School of Physics, University of Sydney, Sydney, NSW, Australia
| | - Paul J Keall
- ACRF Image X Institute, University of Sydney Medical School, Sydney, NSW, Australia
| | - Doan T Nguyen
- ACRF Image X Institute, University of Sydney Medical School, Sydney, NSW, Australia.,School of Biomedical Engineering, University of Technology Sydney, Sydney, NSW, Australia
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Splinter M, Sachpazidis I, Bostel T, Fechter T, Zamboglou C, Thieke C, Jäkel O, Huber PE, Debus J, Baltas D, Nicolay NH. Dosimetric Impact of the Positional Imaging Frequency for Hypofractionated Prostate Radiotherapy - A Voxel-by-Voxel Analysis. Front Oncol 2020; 10:564068. [PMID: 33134166 PMCID: PMC7550661 DOI: 10.3389/fonc.2020.564068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 09/02/2020] [Indexed: 12/25/2022] Open
Abstract
Background To investigate deviations between planned and applied treatment doses for hypofractionated prostate radiotherapy and to quantify dosimetric accuracy in dependence of the image guidance frequency. Methods Daily diagnostic in-room CTs were carried out in 10 patients in treatment position as image guidance for hypofractionated prostate radiotherapy. Fraction doses were mapped to the planning CTs and recalculated, and applied doses were accumulated voxel-wise using deformable registration. Non-daily imaging schedules were simulated by deriving position correction vectors from individual scans and used to rigidly register the following scans until the next repositioning before dose recalculation and accumulation. Planned and applied doses were compared regarding dose-volume indices and TCP and NTCP values in dependence of the imaging and repositioning frequency. Results Daily image-guided repositioning was associated with only negligible deviations of analyzed dose-volume parameters and conformity/homogeneity indices for the prostate, bladder and rectum. Average CTV T did not significantly deviate from the plan values, and rectum NTCPs were highly comparable, while bladder NTCPs were reduced. For non-daily image-guided repositioning, there were significant deviations in the high-dose range from the planned values. Similarly, CTV dose conformity and homogeneity were reduced. While TCPs and rectal NTCPs did not significantly deteriorate for non-daily repositioning, bladder NTCPs appeared falsely diminished in dependence of the imaging frequency. Conclusion Using voxel-by-voxel dose accumulation, we showed for the first time that daily image-guided repositioning resulted in only negligible dosimetric deviations for hypofractionated prostate radiotherapy. Regarding dosimetric aberrations for non-daily imaging, daily imaging is required to adequately deliver treatment.
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Affiliation(s)
- Mona Splinter
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg, Germany
| | - Ilias Sachpazidis
- Department of Radiation Oncology, University of Freiburg - Medical Center, Freiburg im Breisgau, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Tilman Bostel
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, University Medical Center Mainz, Mainz, Germany
| | - Tobias Fechter
- Department of Radiation Oncology, University of Freiburg - Medical Center, Freiburg im Breisgau, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Constantinos Zamboglou
- Department of Radiation Oncology, University of Freiburg - Medical Center, Freiburg im Breisgau, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Christian Thieke
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
| | - Oliver Jäkel
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg, Germany
| | - Peter E Huber
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Jürgen Debus
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Dimos Baltas
- Department of Radiation Oncology, University of Freiburg - Medical Center, Freiburg im Breisgau, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Nils H Nicolay
- Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, University of Freiburg - Medical Center, Freiburg im Breisgau, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
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11
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Gorovets D, Burleson S, Jacobs L, Ravindranath B, Tierney K, Kollmeier M, McBride S, Happersett L, Hunt M, Zelefsky M. Prostate SBRT With Intrafraction Motion Management Using a Novel Linear Accelerator-Based MV-kV Imaging Method. Pract Radiat Oncol 2020; 10:e388-e396. [PMID: 32454176 DOI: 10.1016/j.prro.2020.04.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 04/19/2020] [Accepted: 04/24/2020] [Indexed: 01/10/2023]
Abstract
PURPOSE This study reports clinical experience using a linear accelerator-based MV-kV imaging system for intrafraction motion management during prostate stereotactic body radiation therapy (SBRT). METHODS AND MATERIALS From June 2016 to August 2018, 193 prostate SBRT patients were treated using MV-kV motion management (median dose 40 Gy in 5 fractions). Patients had 3 fiducials implanted then simulated and treated with a full bladder and empty rectum. Pretreatment orthogonal kVs and cone beam computed tomography were used to position patients and evaluate internal anatomy. Motion was tracked during volumetric modulated arc therapy delivery using simultaneously acquired kV and MV images from standard on-board systems. Treatment was interrupted to reposition patients when motion >1.5-2 mm was detected. Motion traces were analyzed and compared with Calypso traces from a previously treated similar patient cohort. To evaluate "natural motion" (ie, if we had not interrupted treatment and repositioned), intrafraction couch corrections were removed from all traces. Clinical effectiveness of the MV-kV system was explored by evaluating toxicity (Common Terminology Criteria for Adverse Events v3.0) and biochemical recurrence rates (nadir + 2 ng/mL). RESULTS Median number of interruptions for patient repositioning was 1 per fraction (range, 0-9). Median overall treatment time was 8.2 minutes (range, 4.2-44.8 minutes). Predominant motion was inferior and posterior, and probability of motion increased with time. Natural motion >3 mm and >5 mm in any direction was observed in 32.3% and 10.2% of fractions, respectively. Calypso monitoring (n = 50) demonstrated similar motion results. In the 151 MV-kV patients with ≥3-month follow-up (median, 9.5 months; range, 3-26.5 months), grade ≥2 acute genitourinary/gastrointestinal and late genitourinary/gastrointestinal toxicity was observed in 9.9%/2.0% and 11.9%/2.7%, respectively. Biochemical control was 99.3% with a single failure in a high-risk patient. CONCLUSIONS The MV-kV system is an effective method to manage intrafraction prostate motion during SBRT, offering the opportunity to correct for prostate clinical target volume displacements that would have otherwise extended beyond typical planning target volume margins.
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Affiliation(s)
- Daniel Gorovets
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York.
| | - Sarah Burleson
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Lauren Jacobs
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Bosky Ravindranath
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Kevin Tierney
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Marisa Kollmeier
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sean McBride
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Laura Happersett
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Margie Hunt
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Michael Zelefsky
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York
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12
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Devlin L, Dodds D, Sadozye A, McLoone P, MacLeod N, Lamb C, Currie S, Thomson S, Duffton A. Dosimetric impact of organ at risk daily variation during prostate stereotactic ablative radiotherapy. Br J Radiol 2020; 93:20190789. [PMID: 31971829 PMCID: PMC7362910 DOI: 10.1259/bjr.20190789] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 12/19/2019] [Accepted: 01/13/2020] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE Prostate stereotactic ablative radiotherapy (SABR) delivers large doses using a fast dose rate. This amplifies the effect geometric uncertainties have on normal tissue dose. The aim of this study was to determine whether the treatment dose-volume histogram (DVH) agrees with the planned dose to organs at risk (OAR). METHODS 41 low-intermediate risk prostate cancer patients were treated with SABR using a linac based technique. Dose prescribed was 35 Gy in five fractions delivered on alternate days, planned using volumetric modulated arc therapy (VMAT) with 10X flattening filter free (FFF). On treatment, prostate was matched to fiducial markers on cone beam CT (CBCT). OAR were retrospectively delineated on 205 pre-treatment CBCT images. Daily CBCT contours were overlaid on the planning CT for dosimetric analysis. Verification plan used to evaluate the daily DVH for each structure. The daily doses received by OAR were recorded using the D%. RESULTS The median rectum and bladder volumes at planning were 67.1 cm3 (interquartile range 56.4-78.2) and 164.4 cm3 (interquartile range 120.3-213.4) respectively. There was no statistically significant difference in median rectal volume at each of the five treatment scans compared to the planning scan (p = 0.99). This was also the case for median bladder volume (p = 0.79). The median dose received by rectum and bladder at each fraction was higher than planned, at the majority of dose levels. For rectum the increase ranged from 0.78-1.64Gy and for bladder 0.14-1.07Gy. The percentage of patients failing for rectum D35% < 18 Gy (p = 0.016), D10% < 28 Gy (p = 0.004), D5% < 32 Gy (p = 0.0001), D1% < 35 Gy (p = 0.0001) and bladder D1% < 35 Gy (p = 0.001) at treatment were all statistically significant. CONCLUSION In this cohort of prostate SABR patients, we estimate the OAR treatment DVH was higher than planned. This was due to rectal and bladder organ variation. ADVANCES IN KNOWLEDGE OAR variation in prostate SABR using a FFF technique, may cause the treatment DVH to be higher than planned.
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Affiliation(s)
- Lynsey Devlin
- Department of Clinical Oncology, Beatson West of Scotland Cancer Centre, Glasgow, United Kingdom
| | - David Dodds
- Department of Clinical Oncology, Beatson West of Scotland Cancer Centre, Glasgow, United Kingdom
| | - Azmat Sadozye
- Department of Clinical Oncology, Beatson West of Scotland Cancer Centre, Glasgow, United Kingdom
| | - Philip McLoone
- Institute of Health & Wellbeing, University of Glasgow, Glasgow, United Kingdom
| | - Nicholas MacLeod
- Department of Clinical Oncology, Beatson West of Scotland Cancer Centre, Glasgow, United Kingdom
| | - Carolynn Lamb
- Department of Clinical Oncology, Beatson West of Scotland Cancer Centre, Glasgow, United Kingdom
| | - Suzanne Currie
- Department of Clinical Physics and Bioengineering, Beatson West of Scotland Cancer Centre, Glasgow, United Kingdom
| | - Stefanie Thomson
- Department of Clinical Physics and Bioengineering, Beatson West of Scotland Cancer Centre, Glasgow, United Kingdom
| | - Aileen Duffton
- Department of Clinical Oncology, Beatson West of Scotland Cancer Centre, Glasgow, United Kingdom
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13
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Splinter M, Bostel T, Sachpazidis I, Fechter T, Zamboglou C, Jäkel O, Huber PE, Debus J, Baltas D, Nicolay NH. Dosimetric Impact of Interfractional Variations for Post-prostatectomy Radiotherapy to the Prostatic Fossa-Relevance for the Frequency of Position Verification Imaging and Treatment Adaptation. Front Oncol 2019; 9:1191. [PMID: 31788450 PMCID: PMC6856079 DOI: 10.3389/fonc.2019.01191] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 10/21/2019] [Indexed: 12/15/2022] Open
Abstract
Background and purpose: To analyze divergences between the planned and applied treatment doses for post-prostatectomy radiotherapy to the prostatic fossa on a voxel-by-voxel basis based on interfractional anatomic variations and imaging frequency. Materials and methods: For 10 patients receiving intensity-modulated postoperative radiotherapy to the prostatic fossa, position verification was carried out by daily in-room CT imaging in treatment position (340 fraction CTs). Applied fraction doses were recalculated on daily CT scans, and treatment doses were accumulated on a voxel-by-voxel basis after deformable image registration. To simulate weekly imaging, derived weekly position correction vectors were used to rigidly register all daily scans of the respective treatment week onto the planning CT before dose accumulation. Detailed dose statistics of the prescribed and applied treatment doses were compared in relation to the frequency of position verification imaging. Derived NTCP and Pinjury values were calculated for the rectum and bladder. Results: Despite a large variability in the pelvic anatomy, daily CT-based patient repositioning resulted in largely negligible deviations of the analyzed dose-volume, conformity, and uniformity parameters from the planned doses for post-prostatectomy radiotherapy, and only the bladder exhibited significant increases in the accumulated mean and median doses. Derived NTCP for the applied doses to the rectum and bladder and Pinjury values did not significantly deviate from the treatment plan. In contrast, weekly CT-based repositioning resulted in significant decreases of the PTV coverage and dose conformity as well as large deviations of the applied doses to the rectum and bladder from the planned doses. Consecutively, NTCP for the rectum and Pinjury were found falsely reduced for weekly patient repositioning. Conclusions: Our data indicate for the first time in a voxel-by-voxel analysis that daily imaging is required for reliable adaptive delivery of intensity-modulated radiotherapy to the prostatic fossa. This work will help guiding adaptive treatment strategies for post-prostatectomy radiotherapy.
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Affiliation(s)
- Mona Splinter
- Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Clinical Cooperation Unit "Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Tilman Bostel
- Clinical Cooperation Unit "Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany.,Department of Radiation Oncology, University Medical Center Mainz, Mainz, Germany
| | - Ilias Sachpazidis
- Department of Radiation Oncology, Medical Center - University of Freiburg, Freiburg, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Tobias Fechter
- Department of Radiation Oncology, Medical Center - University of Freiburg, Freiburg, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Constantinos Zamboglou
- Department of Radiation Oncology, Medical Center - University of Freiburg, Freiburg, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Oliver Jäkel
- Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Peter E Huber
- Clinical Cooperation Unit "Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Jürgen Debus
- Clinical Cooperation Unit "Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Dimos Baltas
- Department of Radiation Oncology, Medical Center - University of Freiburg, Freiburg, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Nils H Nicolay
- Clinical Cooperation Unit "Radiation Oncology, German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany.,Department of Radiation Oncology, Medical Center - University of Freiburg, Freiburg, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
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14
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Bostel T, Sachpazidis I, Splinter M, Bougatf N, Fechter T, Zamboglou C, Jäkel O, Huber PE, Baltas D, Debus J, Nicolay NH. Dosimetric Impact of Interfractional Variations in Prostate Cancer Radiotherapy-Implications for Imaging Frequency and Treatment Adaptation. Front Oncol 2019; 9:940. [PMID: 31612106 PMCID: PMC6776888 DOI: 10.3389/fonc.2019.00940] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 09/06/2019] [Indexed: 02/06/2023] Open
Abstract
Background and purpose: To analyze deviations of the applied from the planned doses on a voxel-by-voxel basis for definitive prostate cancer radiotherapy depending on anatomic variations and imaging frequency. Materials and methods: Daily in-room CT imaging was performed in treatment position for 10 patients with prostate cancer undergoing intensity-modulated radiotherapy (340 fraction CTs). Applied fraction doses were recalculated on daily images, and voxel-wise dose accumulation was performed using a deformable registration algorithm. For weekly imaging, weekly position correction vectors were derived and used to rigidly register daily scans of that week to the planning CT scan prior to dose accumulation. Applied and prescribed doses were compared in dependence of the imaging frequency, and derived TCP and NTCP values were calculated. Results: Daily CT-based repositioning resulted in non-significant deviations of all analyzed dose-volume, conformity and uniformity parameters to the CTV, bladder and rectum irrespective of anatomic changes. Derived average TCP values were comparable, and NTCP values for the applied doses to the bladder and rectum did not significantly deviate from the planned values. For weekly imaging, the applied D2 to the CTV, rectum and bladder significantly varied from the planned doses, and the CTV conformity index and D98 decreased. While TCP values were comparable, the NTCP for the bladder erroneously appeared reduced for weekly repositioning. Conclusions: Based on daily diagnostic quality CT imaging and voxel-wise dose accumulation, we demonstrated for the first time that daily, but not weekly imaging resulted in only negligible deviations of the applied from the planned doses for prostate intensity-modulated radiotherapy. Therefore, weekly imaging may not be adequately reliable for adaptive treatment delivery techniques for prostate. This work will contribute to devising adaptive re-planning strategies for prostate radiotherapy.
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Affiliation(s)
- Tilman Bostel
- Clinical Cooperation Unit "Radiation Oncology", German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany.,Department of Radiation Oncology, University Medical Center Mainz, Mainz, Germany
| | - Ilias Sachpazidis
- Department of Radiation Oncology, University of Freiburg Medical Center, Freiburg, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Mona Splinter
- Heidelberg Institute of Radiation Oncology, National Center for Radiation Research in Oncology, Heidelberg, Germany.,Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg, Germany
| | - Nina Bougatf
- Clinical Cooperation Unit "Radiation Oncology", German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, National Center for Radiation Research in Oncology, Heidelberg, Germany
| | - Tobias Fechter
- Department of Radiation Oncology, University of Freiburg Medical Center, Freiburg, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Constantinos Zamboglou
- Department of Radiation Oncology, University of Freiburg Medical Center, Freiburg, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Oliver Jäkel
- Heidelberg Institute of Radiation Oncology, National Center for Radiation Research in Oncology, Heidelberg, Germany.,Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg, Germany
| | - Peter E Huber
- Clinical Cooperation Unit "Radiation Oncology", German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, National Center for Radiation Research in Oncology, Heidelberg, Germany
| | - Dimos Baltas
- Department of Radiation Oncology, University of Freiburg Medical Center, Freiburg, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
| | - Jürgen Debus
- Clinical Cooperation Unit "Radiation Oncology", German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology, National Center for Radiation Research in Oncology, Heidelberg, Germany
| | - Nils H Nicolay
- Clinical Cooperation Unit "Radiation Oncology", German Cancer Research Center, Heidelberg, Germany.,Department of Radiation Oncology, University of Freiburg Medical Center, Freiburg, Germany.,German Cancer Consortium (DKTK), Partner Site Freiburg, German Cancer Research Center, Heidelberg, Germany
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15
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Zhou Y, Yuan J, Wong OL, Fung WWK, Cheng KF, Cheung KY, Yu SK. Assessment of positional reproducibility in the head and neck on a 1.5-T MR simulator for an offline MR-guided radiotherapy solution. Quant Imaging Med Surg 2018; 8:925-935. [PMID: 30505721 DOI: 10.21037/qims.2018.10.03] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background Recently, a shuttle-based offline magnetic resonance-guided radiotherapy (MRgRT) approach was proposed. This study aims to evaluate the positional reproducibility in the immobilized head and neck using a 1.5-T MR-simulator (MR-sim) on healthy volunteers. Methods A total of 159 scans of 14 healthy volunteers were conducted on a 1.5-T MR-sim with thermoplastic mask immobilization. MR images with isotropic 1.053 mm3 voxel size were rigidly registered to the first scan based on fiducial, anatomical and gross positions. Mean and standard deviation of positional displacements in translation and rotation were assessed. Systematic error and random errors of positioning in the head and neck on the MR-sim were determined in the translation of, and in the rotation of roll, pitch and yaw. Results The systematic error (Σ) of translation in left-right (LR), anterior-posterior (AP) and superior-inferior (SI) direction was 0.57, 0.22 and 0.26 mm for fiducial displacement, 0.28, 0.10 and 0.52 mm for anatomical displacement, and 0.53, 0.22 and 0.49 mm for gross displacement, respectively. The random error (σ) in corresponding translation direction was 2.07, 0.54 and 1.32 mm for fiducial displacement, 1.34, 0.73 and 2.04 mm for anatomical displacement, and 2.24, 0.86 and 2.61 mm for gross displacement. The systematic error and random error of rotation were generally smaller than 1°. Conclusions Our results suggested that high gross positional reproducibility (<1 mm translational and <1° rotational systematic error) could be achieved on an MR-sim for the proposed offline MRgRT.
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Affiliation(s)
- Yihang Zhou
- Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Hong Kong, China
| | - Jing Yuan
- Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Hong Kong, China
| | - Oi Lei Wong
- Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Hong Kong, China
| | - Winky Wing Ki Fung
- Department of Radiotherapy, Hong Kong Sanatorium & Hospital, Hong Kong, China
| | - Ka Fai Cheng
- Department of Radiotherapy, Hong Kong Sanatorium & Hospital, Hong Kong, China
| | - Kin Yin Cheung
- Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Hong Kong, China
| | - Siu Ki Yu
- Medical Physics and Research Department, Hong Kong Sanatorium & Hospital, Hong Kong, China
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16
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Kurz C, Süss P, Arnsmeyer C, Haehnle J, Teichert K, Landry G, Hofmaier J, Exner F, Hille L, Kamp F, Thieke C, Ganswindt U, Valentini C, Hölscher T, Troost E, Krause M, Belka C, Küfer KH, Parodi K, Richter C. Dose-guided patient positioning in proton radiotherapy using multicriteria-optimization. Z Med Phys 2018; 29:216-228. [PMID: 30409729 DOI: 10.1016/j.zemedi.2018.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 10/01/2018] [Accepted: 10/15/2018] [Indexed: 12/25/2022]
Abstract
Proton radiotherapy (PT) requires accurate target alignment before each treatment fraction, ideally utilizing 3D in-room X-ray computed tomography (CT) imaging. Typically, the optimal patient position is determined based on anatomical landmarks or implanted markers. In the presence of non-rigid anatomical changes, however, the planning scenario cannot be exactly reproduced and positioning should rather aim at finding the optimal position in terms of the actually applied dose. In this work, dose-guided patient alignment, implemented as multicriterial optimization (MCO) problem, was investigated in the scope of intensity-modulated and double-scattered PT (IMPT and DSPT) for the first time. A method for automatically determining the optimal patient position with respect to pre-defined clinical goals was implemented. Linear dose interpolation was used to access a continuous space of potential patient shifts. Fourteen head and neck (H&N) and eight prostate cancer patients with up to five repeated CTs were included. Dose interpolation accuracy was evaluated and the potential dosimetric advantages of dose-guided over bony-anatomy-based patient alignment investigated by comparison of clinically relevant target and organ-at-risk (OAR) dose-volume histogram (DVH) parameters. Dose interpolation was found sufficiently accurate with average pass-rates of 90% and 99% for an exemplary H&N and prostate patient, respectively, using a 2% dose-difference criterion. Compared to bony-anatomy-based alignment, the main impact of automated MCO-based dose-guided positioning was a reduced dose to the serial OARs (spinal cord and brain stem) for the H&N cohort. For the prostate cohort, under-dosage of the target structures could be efficiently diminished. Limitations of dose-guided positioning were mainly found in reducing target over-dosage due to weight loss for H&N patients, which might require adaptation of the treatment plan. Since labor-intense online quality-assurance is not required for dose-guided patient positioning, it might, nevertheless, be considered an interesting alternative to full online re-planning for initially mitigating the effects of anatomical changes.
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Affiliation(s)
- Christopher Kurz
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377 München, Germany; Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching bei München, Germany.
| | - Philipp Süss
- Fraunhofer Institute for Industrial Mathematics (ITWM), Fraunhofer-Platz 1, 67663 Kaiserslautern, Germany
| | - Carolin Arnsmeyer
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Fetscherstr. 74, PF 41, 01307 Dresden, Germany
| | - Jonas Haehnle
- Fraunhofer Institute for Industrial Mathematics (ITWM), Fraunhofer-Platz 1, 67663 Kaiserslautern, Germany
| | - Katrin Teichert
- Fraunhofer Institute for Industrial Mathematics (ITWM), Fraunhofer-Platz 1, 67663 Kaiserslautern, Germany
| | - Guillaume Landry
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching bei München, Germany
| | - Jan Hofmaier
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377 München, Germany
| | - Florian Exner
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Fetscherstr. 74, PF 41, 01307 Dresden, Germany
| | - Lucas Hille
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching bei München, Germany
| | - Florian Kamp
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377 München, Germany
| | - Christian Thieke
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377 München, Germany
| | - Ute Ganswindt
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377 München, Germany
| | - Chiara Valentini
- Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Tobias Hölscher
- Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany
| | - Esther Troost
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Fetscherstr. 74, PF 41, 01307 Dresden, Germany; Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany; German Cancer Consortium (DKTK) partner site Dresden, Germany and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Bautzner Landstr. 400, 01328 Dresden, Germany; National Center for Tumor Diseases (NCT), partner site Dresden, Germany
| | - Mechthild Krause
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Fetscherstr. 74, PF 41, 01307 Dresden, Germany; Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany; German Cancer Consortium (DKTK) partner site Dresden, Germany and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Bautzner Landstr. 400, 01328 Dresden, Germany; National Center for Tumor Diseases (NCT), partner site Dresden, Germany
| | - Claus Belka
- Department of Radiation Oncology, University Hospital, LMU Munich, Marchioninistraße 15, 81377 München, Germany; German Cancer Consortium (DKTK) partner site Munich, Germany and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Karl-Heinz Küfer
- Fraunhofer Institute for Industrial Mathematics (ITWM), Fraunhofer-Platz 1, 67663 Kaiserslautern, Germany
| | - Katia Parodi
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, Am Coulombwall 1, 85748 Garching bei München, Germany
| | - Christian Richter
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Fetscherstr. 74, PF 41, 01307 Dresden, Germany; Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Fetscherstr. 74, 01307 Dresden, Germany; German Cancer Consortium (DKTK) partner site Dresden, Germany and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany; Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Bautzner Landstr. 400, 01328 Dresden, Germany
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La radiothérapie externe guidée par l’imagerie dans le cancer de la prostate ; comment, quand et pourquoi ? Cancer Radiother 2018; 22:586-592. [DOI: 10.1016/j.canrad.2018.06.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Accepted: 06/29/2018] [Indexed: 12/14/2022]
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Hirose K, Sato M, Hatayama Y, Kawaguchi H, Komai F, Sohma M, Obara H, Suzuki M, Tanaka M, Fujioka I, Ichise K, Takai Y, Aoki M. The potential failure risk of the cone-beam computed tomography-based planning target volume margin definition for prostate image-guided radiotherapy based on a prospective single-institutional hybrid analysis. Radiat Oncol 2018; 13:106. [PMID: 29880006 PMCID: PMC5992771 DOI: 10.1186/s13014-018-1043-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/02/2018] [Indexed: 11/10/2022] Open
Abstract
Background The purpose of this study was to evaluate the impact of markerless on-board kilovoltage (kV) cone-beam computed tomography (CBCT)-based positioning uncertainty on determination of the planning target volume (PTV) margin by comparison with kV on-board imaging (OBI) with gold fiducial markers (FMs), and to validate a methodology for the evaluation of PTV margins for markerless kV-CBCT in prostate image-guided radiotherapy (IGRT). Methods A total of 1177 pre- and 1177 post-treatment kV-OBI and 1177 pre- and 206 post-treatment kV-CBCT images were analyzed in 25 patients who received prostate IGRT with daily localization by implanted FMs. Intrafractional motion of the prostate was evaluated between each pre- and post-treatment image with these two different techniques. The differences in prostate deviations and intrafractional motions between matching by FM in kV-OBI (OBI-FM) and matching by soft tissues in kV-CBCT (CBCT-ST) were compared by Bland-Altman limits of agreement. Compensated PTV margins were determined and compensated by references. Results Mean differences between OBI-FM and CBCT-ST in the anterior to posterior (AP), superior to inferior (SI), and left to right (LR) directions were − 0.43 ± 1.45, − 0.09 ± 1.65, and − 0.12 ± 0.80 mm, respectively, with R2 = 0.85, 0.88, and 0.83, respectively. Intrafractional motions obtained from CBCT-ST were 0.00 ± 1.46, 0.02 ± 1.49, and 0.15 ± 0.64 mm, respectively, which were smaller than the results from OBI-FM, with 0.43 ± 1.90, 0.12 ± 1.98, and 0.26 ± 0.80 mm, respectively, with R2 = 0.42, 0.33, and 0.16, respectively. Bland-Altman analysis showed a significant proportional bias. PTV margins of 1.5 mm, 1.4 mm, and 0.9 mm for CBCT-ST were calculated from the values of CBCT-ST, which were also smaller than the values of 3.15 mm, 3.66 mm, and 1.60 mm from OBI-FM. The practical PTV margin for CBCT-ST was compensated with the values from OBI-FM as 4.1 mm, 4.8 mm, and 2.2 mm. Conclusions PTV margins calculated from CBCT-ST might be underestimated compared to the true PTV margins. To determine a reliable CBCT-ST-based PTV margin, at least the systemic error Σ and the random error σ for on-line matching errors need to be investigated by supportive preliminary FM evaluation at least once.
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Affiliation(s)
- Katsumi Hirose
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan. .,Department of Radiation Oncology, Southern Tohoku BNCT Research Center, 7-10, Yatsuyamada, Koriyama, Fukushima, 963-8052, Japan.
| | - Mariko Sato
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Yoshiomi Hatayama
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Hideo Kawaguchi
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Fumio Komai
- Division of Radiology, Hirosaki University Hospital, 53 Hon-cho, Hirosaki, Aomori, 036-8563, Japan
| | - Makoto Sohma
- Division of Radiology, Hirosaki University Hospital, 53 Hon-cho, Hirosaki, Aomori, 036-8563, Japan
| | - Hideki Obara
- Division of Radiology, Hirosaki University Hospital, 53 Hon-cho, Hirosaki, Aomori, 036-8563, Japan
| | - Masashi Suzuki
- Division of Radiology, Hirosaki University Hospital, 53 Hon-cho, Hirosaki, Aomori, 036-8563, Japan
| | - Mitsuki Tanaka
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Ichitaro Fujioka
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Koji Ichise
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
| | - Yoshihiro Takai
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan.,Department of Radiation Oncology, Southern Tohoku BNCT Research Center, 7-10, Yatsuyamada, Koriyama, Fukushima, 963-8052, Japan
| | - Masahiko Aoki
- Department of Radiology and Radiation Oncology, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan
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Wang G, Wang WL, Liu YQ, Dong HM, Hu YX. Positioning error and expanding margins of planning target volume with kilovoltage cone beam computed tomography for prostate cancer radiotherapy. Onco Targets Ther 2018; 11:1981-1988. [PMID: 29670373 PMCID: PMC5898597 DOI: 10.2147/ott.s152915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Objective In this study, prostate cancer patients were treated with image-guided radiotherapy (IGRT). The translational positioning errors were discussed to provide the basis for determining margins of the planning target volume (PTV). Methods Thirty prostate cancer patients were treated with radical radiotherapy using the IGRT system. Patients were placed in the supine position and underwent kilovoltage cone beam computed tomography (KVCBCT) scans before radiotherapy. A total of 447 images were acquired. The translational positioning errors were obtained in three linear directions which were X (left-to-right), Y (superior-to-inferior) and Z (anterior-to-posterior) axes (denoted as Lx, Ly and Lz) through the contrast between images adjusted with gray and manual registrations and the planning CT images. Rotational errors were denoted as Rx, Ry and Rz. Results Uncorrected translational errors Lx, Ly and Lz in the 251 positioning images were all higher than those after correction, and the differences were all statistically significant (P=0.000, 0.037 and 0.004, respectively). For rotational errors Rx, Ry and Rz, only Rx had a significant difference before and after correction (P=0.044). Before correction, PTV margins in the X, Y and Z directions were 0.61, 0.78 and 0.41 cm, respectively; after correction, these were 0.17, 0.12 and 0.17 cm, respectively. Conclusion KVCBCT can be applied to measure positioning errors in prostate cancer radiotherapy and correct these errors in real time through the 6° robotic patient positioning system, in order to improve patient positioning accuracy. The application of IGRT with KVCBCT may reduce PTV margins.
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Affiliation(s)
- Gang Wang
- Department of Abdominal Oncology, Affiliated Hospital of Guizhou Medical University, Guizhou Cancer Hospital, Guiyang, People's Republic of China
| | - Wen-Ling Wang
- Department of Abdominal Oncology, Affiliated Hospital of Guizhou Medical University, Guizhou Cancer Hospital, Guiyang, People's Republic of China
| | - Yi-Qun Liu
- Department of Abdominal Oncology, Affiliated Hospital of Guizhou Medical University, Guizhou Cancer Hospital, Guiyang, People's Republic of China
| | - Hong-Min Dong
- Department of Abdominal Oncology, Affiliated Hospital of Guizhou Medical University, Guizhou Cancer Hospital, Guiyang, People's Republic of China
| | - Yin-Xiang Hu
- Department of Abdominal Oncology, Affiliated Hospital of Guizhou Medical University, Guizhou Cancer Hospital, Guiyang, People's Republic of China
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20
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Iwata H, Ishikawa H, Takagi M, Okimoto T, Murayama S, Akimoto T, Wada H, Arimura T, Sato Y, Araya M, Mizoe J, Gosho M, Nakamura K, Shirato H, Sakurai H. Long-term outcomes of proton therapy for prostate cancer in Japan: a multi-institutional survey of the Japanese Radiation Oncology Study Group. Cancer Med 2018; 7:677-689. [PMID: 29441697 PMCID: PMC5852348 DOI: 10.1002/cam4.1350] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 11/14/2017] [Accepted: 12/28/2017] [Indexed: 01/03/2023] Open
Abstract
This is the first multi‐institutional retrospective survey of the long‐term outcomes of proton therapy (PT) for prostate cancer in Japan. This retrospective analysis comprised prostate cancer patients treated with PT at seven centers between January 2008 and December 2011 and was approved by each Institutional Review Board. The NCCN classification was used. Biochemical relapse was based on the Phoenix definition (nadir + 2.0 ng/mL). Toxicities were evaluated with the Common Terminology Criteria for Adverse Events version 4.0. There were 215, 520, and 556 patients in the low‐risk, intermediate‐risk, and high‐risk groups, respectively. The median follow‐up period of surviving patients was 69 months (range: 7–107). Among all patients, 98.8% were treated using a conventional fractionation schedule and 1.2% with a hypofractionation schedule; 58.5% and 21.5% received neoadjuvant and adjuvant androgen deprivation therapy, respectively. The 5‐year biochemical relapse‐free survival (bRFS) and overall survival rates in the low‐risk, intermediate‐risk, and high‐risk groups were 97.0%, 91.1%, and 83.1%, and 98.4%, 96.8%, and 95.2%, respectively. In the multivariate analysis, the NCCN classification was a significant prognostic factor for bRFS, but not overall survival. The incidence rates of grade 2 or more severe late gastrointestinal and genitourinary toxicities were 4.1% and 4.0%, retrospectively. This retrospective analysis of a multi‐institutional survey suggested that PT is effective and well‐tolerated for prostate cancer. Based on this result, a multi‐institutional prospective clinical trial (UMIN000025453) on PT for prostate cancer has just been initiated in order to define its role in Japan.
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Affiliation(s)
- Hiromitsu Iwata
- Department of Radiation OncologyNagoya Proton Therapy CenterNagoya City West Medical CenterNagoyaJapan
- Department of RadiologyNagoya City University Graduate School of Medical SciencesNagoyaJapan
| | - Hitoshi Ishikawa
- Department of Radiation OncologyFaculty of MedicineUniversity of TsukubaTsukubaJapan
| | - Masaru Takagi
- Department of Radiation OncologySapporo Teishinkai HospitalSapporoJapan
- Department of RadiologyHyogo Ion Beam Medical CenterTatsunoJapan
| | - Tomoaki Okimoto
- Department of RadiologyHyogo Ion Beam Medical CenterTatsunoJapan
| | - Sigeyuki Murayama
- Proton Therapy DivisionShizuoka Cancer Center HospitalNagaizumiJapan
| | - Tetsuo Akimoto
- Division of Radiation Oncology and Particle TherapyNational Cancer Center Hospital EastKashiwaJapan
| | - Hitoshi Wada
- Department of Radiation OncologySouthern TOHOKU Proton Therapy CenterKoriyamaJapan
| | | | - Yoshitaka Sato
- Proton Therapy CenterFukui Prefectural HospitalFukuiJapan
| | | | - Jun‐etsu Mizoe
- Department of Radiation OncologyNagoya Proton Therapy CenterNagoya City West Medical CenterNagoyaJapan
| | - Masahiko Gosho
- Department of Clinical Trial and Clinical EpidemiologyFaculty of MedicineUniversity of TsukubaTsukubaJapan
| | - Katsumasa Nakamura
- Department of Radiation OncologyHamamatsu University School of MedicineHamamatsuJapan
| | - Hiroki Shirato
- Department of Radiation MedicineHokkaido University Graduate School of MedicineSapporoJapan
| | - Hideyuki Sakurai
- Department of Radiation OncologyFaculty of MedicineUniversity of TsukubaTsukubaJapan
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Buschmann M, Sharfo AWM, Penninkhof J, Seppenwoolde Y, Goldner G, Georg D, Breedveld S, Heijmen BJM. Automated volumetric modulated arc therapy planning for whole pelvic prostate radiotherapy. Strahlenther Onkol 2017; 194:333-342. [PMID: 29270648 PMCID: PMC5869893 DOI: 10.1007/s00066-017-1246-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Accepted: 11/25/2017] [Indexed: 11/26/2022]
Abstract
Background For several tumor entities, automated treatment planning has improved plan quality and planning efficiency, and may enable adaptive treatment approaches. Whole-pelvic prostate radiotherapy (WPRT) involves large concave target volumes, which present a challenge for volumetric arc therapy (VMAT) optimization. This study evaluates automated VMAT planning for WPRT-VMAT and compares the results with manual expert planning. Methods A system for fully automated multi-criterial plan generation was configured for each step of sequential-boost WPRT-VMAT, with final “autoVMAT” plans being automatically calculated by the Monaco treatment planning system (TPS; Elekta AB, Stockholm, Sweden). Configuration was based on manually generated VMAT plans (manualVMAT) of 5 test patients, the planning protocol, and discussions with the treating physician on wishes for plan improvements. AutoVMAT plans were then generated for another 30 evaluation patients and compared to manualVMAT plans. For all 35 patients, manualVMAT plans were optimized by expert planners using the Monaco TPS. Results AutoVMAT plans exhibited strongly improved organ sparing and higher conformity compared to manualVMAT. On average, mean doses (Dmean) of bladder and rectum were reduced by 10.7 and 4.5 Gy, respectively, by autoVMAT. Prostate target coverage (V95%) was slightly higher (+0.6%) with manualVMAT. In a blinded scoring session, the radiation oncologist preferred autoVMAT plans to manualVMAT plans for 27/30 patients. All treatment plans were considered clinically acceptable. The workload per patient was reduced by > 70 min. Conclusion Automated VMAT planning for complex WPRT dose distributions is feasible and creates treatment plans that are generally dosimetrically superior to manually optimized plans. Electronic supplementary material The online version of this article (10.1007/s00066-017-1246-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Martin Buschmann
- Department of Radiation Oncology, Medical University of Vienna/AKH Wien, Währinger Gürtel 18-20, 1090, Vienna, Austria.
- Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, Vienna, Austria.
| | - Abdul Wahab M Sharfo
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Joan Penninkhof
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Yvette Seppenwoolde
- Department of Radiation Oncology, Medical University of Vienna/AKH Wien, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, Vienna, Austria
| | - Gregor Goldner
- Department of Radiation Oncology, Medical University of Vienna/AKH Wien, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Dietmar Georg
- Department of Radiation Oncology, Medical University of Vienna/AKH Wien, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, Vienna, Austria
| | - Sebastiaan Breedveld
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
| | - Ben J M Heijmen
- Department of Radiation Oncology, Erasmus MC Cancer Institute, Rotterdam, The Netherlands
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22
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Goff PH, Harrison LB, Furhang E, Ng E, Bhatia S, Trichter F, Ennis RD. 2D kV orthogonal imaging with fiducial markers is more precise for daily image guided alignments than soft-tissue cone beam computed tomography for prostate radiation therapy. Adv Radiat Oncol 2017; 2:420-428. [PMID: 29114611 PMCID: PMC5605315 DOI: 10.1016/j.adro.2017.05.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 04/23/2017] [Accepted: 04/27/2017] [Indexed: 12/16/2022] Open
Abstract
Purpose The hypothesis is that 2-dimensional kV orthogonal imaging with fiducial markers (kV-FM) and soft-tissue cone beam computed tomography (ST-CBCT) are equally reproducible for daily positional alignments for image guided (IG) intensity modulated radiation therapy (IMRT) for prostate cancer. Methods and materials Ten patients undergoing definitive treatment for prostate cancer with IG-IMRT were imaged daily with kV-FM and ST-CBCT. For each acquired kV and CBCT image, offline alignments to the digitally reconstructed radiograph or planning CT, respectively, were made twice by the same physician to assess intraobserver test-retest reproducibility. The 256 kV and 142 CBCT images were analyzed, and the test-retest analysis was performed again on a subset of images by another physician to verify the results. Results The results demonstrated that kV-FM had better intraobserver test-retest reproducibility in the anterior-posterior (AP; 95% confidence interval [CI] Pearson correlation coefficient [r], 0.987-0.991), left-right (LR; 95% CI r, 0.955-0.969), and superior-inferior (SI; 95% CI r, 0.971-0.980) directions for daily IG alignments compared with ST-CBCT (AP: 95% CI r, 0.804-0.877; LR: 95% CI r, 0.877-0.924; SI: 95% CI r, 0.791-0.869). Errors associated with intraobserver test-retest reproducibility were submillimeter with kV-FM (AP: 0.4 ± 0.7 mm; RL: 0.4 ± 1.0 mm; SI: 0.5 ± 0.7 mm) compared with ST-CBCT (AP: 2.1 ± 2.2 mm; LR: 1.3 ± 1.4 mm; SI: 1.2 ± 1.8 mm). The mean shift differences between kV-FM and ST-CBCT were 0.3 ± 3.8 mm for AP, −1.1 ± 8.5 mm for LR, and −2.0 ± 3.7 mm for SI. Dose-volume histograms were generated and showed that test-retest variability associated with ST-CBCT IG-alignments resulted in significantly increased dose to normal structures and a reduced planning target volume dose in many patients. Conclusions The kV-FM–based daily IG alignment for IMRT of prostate cancer is more precise than ST-CBCT, as assessed by a physician's ability to reproducibly align images. Given the magnitude of the error introduced by inconsistency in making ST-CBCT alignments, these data support a role for daily kV imaging of FM to enhance the precision of external beam dose delivery to the prostate.
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Affiliation(s)
- Peter H Goff
- Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Louis B Harrison
- H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida
| | - Eli Furhang
- Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai and Mount Sinai West Hospital, New York, New York
| | - Evan Ng
- Genesis Cancer Care, Western Australia, Wembley, Australia
| | - Stephen Bhatia
- Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai and Mount Sinai West Hospital, New York, New York
| | - Frieda Trichter
- Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai and Mount Sinai West Hospital, New York, New York
| | - Ronald D Ennis
- Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai and Mount Sinai West Hospital, New York, New York
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Orlandini LC, Coppola M, Fulcheri C, Cernusco L, Wang P, Cionini L. Dose tracking assessment for image-guided radiotherapy of the prostate bed and the impact on clinical workflow. Radiat Oncol 2017; 12:78. [PMID: 28454559 PMCID: PMC5410096 DOI: 10.1186/s13014-017-0815-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 04/25/2017] [Indexed: 11/10/2022] Open
Abstract
Background The cumulative dose was compared with the planned dose among fourteen patients undergoing image-guided, intensity-modulated radiotherapy of the prostate bed. Moreover, we investigated the feasibility of adding dose tracking to the routine workflow for radiotherapy. Methods Daily cone beam computed tomography was conducted for image-guided radiotherapy, and weekly cumulative delivered doses were calculated for dose tracking. Deformable image registration was applied to map weekly dose distributions to the original treatment plan and to create a cumulative dose distribution. The dose–volume histogram (DVH) cut-off points for the rectum and bladder and the planning target volume (PTV), were used to compare the planned and cumulative delivered doses. The additional time required by the departmental staff to complete these duties was recorded. Results The PTV coverage of the delivered treatment did not satisfy the expected goal for three patients (V98% >98%). In another three patients, the DVH cut-off point for the bladder was higher than the limits, while for the rectum, treatment was as expected in all cases (two patients failed both their bladder constraints and the PTV coverage). Overall, four patients did not satisfy one or more criteria at the end of their treatment. Conclusions A well-defined strategy for dose tracking assessment is feasible, would have minimal impact on the workload of a radiotherapy department, and may offer objective information to support radiation oncologists in making decisions about adaptive procedures.
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Affiliation(s)
- Lucia Clara Orlandini
- Centro Oncologico Fiorentino, Radiation Oncology Department, Via A. Ragionieri 101, 50023, Florence, Italy.,Department of Radiation Oncology, Sichuan Cancer Hospital, No.55, the 4th Section, Renmin South Road, Chengdu, China
| | - Marianna Coppola
- Centro Oncologico Fiorentino, Radiation Oncology Department, Via A. Ragionieri 101, 50023, Florence, Italy
| | - Christian Fulcheri
- Azienda Ospedaliera di Perugia, Health Physics Department, Piazzale Menghini 1, 06129, Perugia, Italy
| | - Luna Cernusco
- Centro Oncologico Fiorentino, Radiation Oncology Department, Via A. Ragionieri 101, 50023, Florence, Italy
| | - Pei Wang
- Department of Radiation Oncology, Sichuan Cancer Hospital, No.55, the 4th Section, Renmin South Road, Chengdu, China.
| | - Luca Cionini
- Centro Oncologico Fiorentino, Radiation Oncology Department, Via A. Ragionieri 101, 50023, Florence, Italy
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Onal C, Dolek Y, Ozdemir Y. The impact of androgen deprivation therapy on setup errors during external beam radiation therapy for prostate cancer. Strahlenther Onkol 2017; 193:472-482. [PMID: 28409246 DOI: 10.1007/s00066-017-1131-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 03/22/2017] [Indexed: 02/03/2023]
Abstract
PURPOSE To determine whether setup errors during external beam radiation therapy (RT) for prostate cancer are influenced by the combination of androgen deprivation treatment (ADT) and RT. MATERIALS AND METHODS Data from 175 patients treated for prostate cancer were retrospectively analyzed. Treatment was as follows: concurrent ADT plus RT, 33 patients (19%); neoadjuvant and concurrent ADT plus RT, 91 patients (52%); RT only, 51 patients (29%). Required couch shifts without rotations were recorded for each megavoltage (MV) cone beam computed tomography (CBCT) scan, and corresponding alignment shifts were recorded as left-right (x), superior-inferior (y), and anterior-posterior (z). The nonparametric Mann-Whitney test was used to compare shifts by group. Pearson's correlation coefficient was used to measure the correlation of couch shifts between groups. Mean prostate shifts and standard deviations (SD) were calculated and pooled to obtain mean or group systematic error (M), SD of systematic error (Σ), and SD of random error (σ). RESULTS No significant differences were observed in prostate shifts in any direction between the groups. Shifts on CBCT were all less than setup margins. A significant positive correlation was observed between prostate volume and the z‑direction prostate shift (r = 0.19, p = 0.04), regardless of ADT group, but not between volume and x‑ or y‑direction shifts (r = 0.04, p = 0.7; r = 0.03, p = 0.7). Random and systematic errors for all patient cohorts and ADT groups were similar. CONCLUSION Hormone therapy given concurrently with RT was not found to significantly impact setup errors. Prostate volume was significantly correlated with shifts in the anterior-posterior direction only.
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Affiliation(s)
- Cem Onal
- Faculty of Medicine, Adana Dr. Turgut Noyan Research and Treatment Centre, Department of Radiation Oncology, Baskent University, 01120, Adana, Turkey.
| | - Yemliha Dolek
- Faculty of Medicine, Adana Dr. Turgut Noyan Research and Treatment Centre, Department of Radiation Oncology, Baskent University, 01120, Adana, Turkey
| | - Yurday Ozdemir
- Faculty of Medicine, Adana Dr. Turgut Noyan Research and Treatment Centre, Department of Radiation Oncology, Baskent University, 01120, Adana, Turkey
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Haehnle J, Süss P, Landry G, Teichert K, Hille L, Hofmaier J, Nowak D, Kamp F, Reiner M, Thieke C, Ganswindt U, Belka C, Parodi K, Küfer KH, Kurz C. A novel method for interactive multi-objective dose-guided patient positioning. Phys Med Biol 2016; 62:165-185. [DOI: 10.1088/1361-6560/62/1/165] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Yildirim BA, Onal C, Dolek Y. Is it essential to use fiducial markers during cone-beam CT-based radiotherapy for prostate cancer patients? Jpn J Radiol 2016; 35:3-9. [PMID: 27730453 DOI: 10.1007/s11604-016-0590-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 09/29/2016] [Indexed: 12/31/2022]
Abstract
PURPOSE To compare soft-tissue cone-beam computed tomography (CBCT-P) and fiducial marker (CBCT-FM)-based image guided radiotherapy in prostate cancer patients. MATERIALS AND METHODS Sixteen prostate cancer patients were treated with volumetric modulated arc therapy. Manual alignment using CBCT-P and CBCT-FM was performed for each patient. Couch shifts were calculated and compared between methods in the left-right (x), superior-inferior (y), and anterior-posterior (z) directions. RESULTS CBCT-P and CBCT-FM alignments were compared using 252 scans from the 16 patients. Mean displacement from zero was 2.4 ± 1.3, 1.7 ± 1.2, and 1.8 ± 1.1 mm for CBCT-P and 2.3 ± 1.3, 1.7 ± 1.1 and 1.8 ± 1.1 mm for CBCT-FM in the x, y and z directions, respectively. There was no difference in median displacement between CBCT-P and CBCT-FM; however, there was a significant positive correlation between CBCT-P- and CBCT-FM-based displacements in the x (r = 0.881; p < 0.001), y (r = 0.789; p < 0.001) and z (r = 0.856; p < 0.001) directions by linear regression analysis. Systematic deviations within each group were <1 mm; however, random and systematic errors were similar in the x and y directions but larger in the z direction. CONCLUSION Our study demonstrated that CBCT-FM was not superior to CBCT-P for image-guided radiotherapy in prostate cancer patients.
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Affiliation(s)
- Berna A Yildirim
- Department of Radiation Oncology, Baskent University Faculty of Medicine, 01120, Adana, Turkey
| | - Cem Onal
- Department of Radiation Oncology, Baskent University Faculty of Medicine, 01120, Adana, Turkey.
| | - Yemliha Dolek
- Department of Radiation Oncology, Baskent University Faculty of Medicine, 01120, Adana, Turkey
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Kurz C, Kamp F, Park YK, Zöllner C, Rit S, Hansen D, Podesta M, Sharp GC, Li M, Reiner M, Hofmaier J, Neppl S, Thieke C, Nijhuis R, Ganswindt U, Belka C, Winey BA, Parodi K, Landry G. Investigating deformable image registration and scatter correction for CBCT-based dose calculation in adaptive IMPT. Med Phys 2016; 43:5635. [DOI: 10.1118/1.4962933] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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Ramiandrisoa F, Duvergé L, Castelli J, Nguyen TD, Servagi-Vernat S, de Crevoisier R. [Clinical to planning target volume margins in prostate cancer radiotherapy]. Cancer Radiother 2016; 20:629-39. [PMID: 27614515 DOI: 10.1016/j.canrad.2016.07.095] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 07/22/2016] [Accepted: 07/27/2016] [Indexed: 02/03/2023]
Abstract
The knowledge of inter- and intrafraction motion and deformations of the intrapelvic target volumes (prostate, seminal vesicles, prostatectomy bed and lymph nodes) as well as the main organs at risk (bladder and rectum) allow to define rational clinical to planning target volume margins, depending on the different radiotherapy techniques and their uncertainties. In case of image-guided radiotherapy, prostate margins and seminal vesicles margins can be between 5 and 10mm. The margins around the prostatectomy bed vary from 10 to 15mm and those around the lymph node clinical target volume between 7 and 10mm. Stereotactic body radiotherapy allows lower margins, which are 3 to 5mm around the prostate. Image-guided and stereotactic body radiotherapy with adequate margins allow finally moderate or extreme hypofractionation.
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Affiliation(s)
- F Ramiandrisoa
- Département de radiothérapie, institut Jean-Godinot, 1, rue du Général-Kœnig, 51100 Reims, France.
| | - L Duvergé
- Département de radiothérapie, centre Eugène-Marquis, avenue de la Bataille-Flandres-Dunkerque, 35000 Rennes, France
| | - J Castelli
- Département de radiothérapie, centre Eugène-Marquis, avenue de la Bataille-Flandres-Dunkerque, 35000 Rennes, France; LTSI, campus de Beaulieu, université de Rennes 1, 35000 Rennes, France; Inserm U1099, campus de Beaulieu, 35000 Rennes, France
| | - T D Nguyen
- Département de radiothérapie, institut Jean-Godinot, 1, rue du Général-Kœnig, 51100 Reims, France
| | - S Servagi-Vernat
- Département de radiothérapie, institut Jean-Godinot, 1, rue du Général-Kœnig, 51100 Reims, France
| | - R de Crevoisier
- Département de radiothérapie, centre Eugène-Marquis, avenue de la Bataille-Flandres-Dunkerque, 35000 Rennes, France; LTSI, campus de Beaulieu, université de Rennes 1, 35000 Rennes, France; Inserm U1099, campus de Beaulieu, 35000 Rennes, France
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Accuracy in automatic image registration between MV cone beam computed tomography and planning kV computed tomography in image guided radiotherapy. Rep Pract Oncol Radiother 2016; 21:487-94. [PMID: 27489520 DOI: 10.1016/j.rpor.2016.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Revised: 12/04/2015] [Accepted: 07/06/2016] [Indexed: 11/23/2022] Open
Abstract
AIM To verify the accuracy of automatic image registration (IR) between the planning kilo voltage computed tomography (kV CT) and megavoltage cone beam computed tomography (MV CBCT) datasets using phantom and patient images. BACKGROUND The automatic IR between MV CBCT and planning kV CT is a fast solution for performing online image guided radiotherapy (IGRT). The IR accuracy has to be verified periodically as it directly affects patient setup accuracy. MATERIALS AND METHODS The automatic IR accuracy was evaluated using image quality phantom acquired with different kV CT slice thickness, different MV CBCT acquisition MUs and reconstruction slice size and thickness. The IR accuracy was also evaluated on patient images on different anatomical sites such as brain, head & neck, thorax and pelvis. The uncertainty in the automatic registration was assessed by introducing known offset to kV CT dataset and compared with the registration results. RESULTS The result with the phantom images was within 2 mm in all three translational directions. The accuracy in automatic IR using patient images was within 2 mm in most of the cases. 3 mm planning kV CT slice thickness was sufficient to perform automatic IR successfully within 2 mm accuracy. The MV CBCT reconstruction parameters such as slice thickness and slice size had no effect on the registration accuracy. CONCLUSION This study shows that the automatic IR is accurate within 2 mm and provides confidence in performing them between planning kV CT and MV CBCT image datasets for online image guided radiotherapy.
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McPartlin AJ, Li XA, Kershaw LE, Heide U, Kerkmeijer L, Lawton C, Mahmood U, Pos F, van As N, van Herk M, Vesprini D, van der Voort van Zyp J, Tree A, Choudhury A. MRI-guided prostate adaptive radiotherapy - A systematic review. Radiother Oncol 2016; 119:371-80. [PMID: 27162159 DOI: 10.1016/j.radonc.2016.04.014] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 04/08/2016] [Accepted: 04/09/2016] [Indexed: 11/29/2022]
Abstract
Dose escalated radiotherapy improves outcomes for men with prostate cancer. A plateau for benefit from dose escalation using EBRT may not have been reached for some patients with higher risk disease. The use of increasingly conformal techniques, such as step and shoot IMRT or more recently VMAT, has allowed treatment intensification to be achieved whilst minimising associated increases in toxicity to surrounding normal structures. To support further safe dose escalation, the uncertainties in the treatment target position will need be minimised using optimal planning and image-guided radiotherapy (IGRT). In particular the increasing usage of profoundly hypo-fractionated stereotactic therapy is predicated on the ability to confidently direct treatment precisely to the intended target for the duration of each treatment. This article reviews published studies on the influences of varies types of motion on daily prostate position and how these may be mitigated to improve IGRT in future. In particular the role that MRI has played in the generation of data is discussed and the potential role of the MR-Linac in next-generation IGRT is discussed.
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Affiliation(s)
- A J McPartlin
- The Christie NHS Foundation Trust and Manchester Cancer Research Centre, University of Manchester, Manchester Academic Health Sciences Centre, UK
| | - X A Li
- Medical College of Wisconsin, USA
| | - L E Kershaw
- The Christie NHS Foundation Trust and Manchester Cancer Research Centre, University of Manchester, Manchester Academic Health Sciences Centre, UK
| | - U Heide
- Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital, The Netherlands
| | - L Kerkmeijer
- University Medical Center Utrecht, The Netherlands
| | - C Lawton
- Medical College of Wisconsin, USA
| | - U Mahmood
- MD Anderson Cancer Center, Houston, USA
| | - F Pos
- Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital, The Netherlands
| | - N van As
- Royal Marsden Hospital, UK; Institute of Cancer Research, UK
| | - M van Herk
- The Christie NHS Foundation Trust and Manchester Cancer Research Centre, University of Manchester, Manchester Academic Health Sciences Centre, UK
| | - D Vesprini
- Sunnybrook Health Sciences Centre, University of Toronto, Canada
| | | | - A Tree
- Royal Marsden Hospital, UK
| | - A Choudhury
- The Christie NHS Foundation Trust and Manchester Cancer Research Centre, University of Manchester, Manchester Academic Health Sciences Centre, UK.
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Foley D, O'Brien DJ, León-Vintró L, McClean B, McBride P. Phase correlation applied to the 3D registration of CT and CBCT image volumes. Phys Med 2016; 32:618-24. [PMID: 26988935 DOI: 10.1016/j.ejmp.2016.02.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 02/24/2016] [Accepted: 02/25/2016] [Indexed: 11/17/2022] Open
Abstract
PURPOSE In this study, a 3D phase correlation algorithm was investigated to test feasibility for use in determining the anatomical changes that occur throughout a patient's radiotherapy treatment. The algorithm determines the transformations between two image volumes through analysis in the Fourier domain and has not previously been used in radiotherapy for 3D registration of CT and CBCT volumes. METHODS Various known transformations were applied to a patient's prostate CT image volume to create 12 different test cases. The mean absolute error and standard deviation were determined by evaluating the difference between the known contours and those calculated from the registration process on a point-by-point basis. Similar evaluations were performed on images with increasing levels of noise added. The improvement in structure overlap offered by the algorithm in registering clinical CBCT to CT images was evaluated using the Dice Similarity Coefficient (DSC). RESULTS A mean error of 2.35 (σ = 1.54) mm was calculated for the 12 deformations applied. When increasing levels of noise were introduced to the images, the mean errors were observed to rise up to a maximum increase of 1.77 mm. For CBCT to CT registration, maximum improvements in the DSC of 0.09 and 0.46 were observed for the bladder and rectum, respectively. CONCLUSIONS The Fourier-based 3D phase correlation registration algorithm investigated displayed promising results in CT to CT and CT to CBCT registration, offers potential in terms of efficiency and robustness to noise, and is suitable for use in radiotherapy for monitoring patient anatomy throughout treatment.
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Affiliation(s)
- Daniel Foley
- St. Luke's Radiation Oncology Network, Highfield Road, Rathgar, Dublin 6, Ireland; School of Physics, University College Dublin, Belfield, Dublin 4, Ireland.
| | - Daniel J O'Brien
- St. Luke's Radiation Oncology Network, Highfield Road, Rathgar, Dublin 6, Ireland; School of Physics, University College Dublin, Belfield, Dublin 4, Ireland
| | - Luis León-Vintró
- School of Physics, University College Dublin, Belfield, Dublin 4, Ireland
| | - Brendan McClean
- St. Luke's Radiation Oncology Network, Highfield Road, Rathgar, Dublin 6, Ireland
| | - Peter McBride
- St. Luke's Radiation Oncology Network, Highfield Road, Rathgar, Dublin 6, Ireland
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Poli APDF, Dias RS, Giordani AJ, Segreto HRC, Segreto RA. Strategies to evaluate the impact of rectal volume on prostate motion during three-dimensional conformal radiotherapy for prostate cancer. Radiol Bras 2016; 49:17-20. [PMID: 26929456 PMCID: PMC4770392 DOI: 10.1590/0100-3984.2015.0005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Objective To evaluate the rectal volume influence on prostate motion during
three-dimensional conformal radiotherapy (3D-CRT) for prostate cancer. Materials and Methods Fifty-one patients with prostate cancer underwent a series of three computed
tomography scans including an initial planning scan and two subsequent scans
during 3D-CRT. The organs of interest were outlined. The prostate contour
was compared with the initial CT images considering the anterior, posterior,
superior, inferior and lateral edges of the organ. Variations in the
anterior limits and volume of the rectum were assessed and correlated with
prostate motion in the anteroposterior direction. Results The maximum range of prostate motion was observed in the superoinferior
direction, followed by the anteroposterior direction. A significant
correlation was observed between prostate motion and rectal volume variation
(p = 0.037). A baseline rectal volume superior to 70
cm3 had a significant influence on the prostate motion in the
anteroposterior direction (p = 0.045). Conclusion The present study showed a significant interfraction motion of the prostate
during 3D-CRT with greatest variations in the superoinferior and
anteroposterior directions, and that a large rectal volume influences the
prostate motion with a cutoff value of 70 cm3. Therefore, the
treatment of patients with a rectal volume > 70 cm3 should be
re-planned with appropriate rectal preparation.
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Affiliation(s)
- Ana Paula Diniz Fortuna Poli
- PhD, Physician Assistant, Unit of Radiotherapy, Centro de Atenção Integrada à Saúde da Mulher - Universidade Estadual de Campinas (CAISM-Unicamp), Campinas, SP, Brazil
| | - Rodrigo Souza Dias
- PhD, Physician responsible, Unit of Radiotherapy, Department of Clinical and Experimental Oncology, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil
| | - Adelmo José Giordani
- PhD, Physicist responsible, Unit of Radiotherapy, Department of Clinical and Experimental Oncology, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil
| | - Helena Regina Comodo Segreto
- Post-doc Fellow, Associate Professor, Unit of Radiotherapy, Department of Clinical and Experimental Oncology, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil
| | - Roberto Araujo Segreto
- Private Docent, Associate Professor, Unit of Radiotherapy, Department of Clinical and Experimental Oncology, Escola Paulista de Medicina da Universidade Federal de São Paulo (EPM-Unifesp), São Paulo, SP, Brazil
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Grimm M, Wenz F. [Localized prostate cancer: Radiotherapeutic concepts]. Urologe A 2016; 55:326-32. [PMID: 26895435 DOI: 10.1007/s00120-016-0042-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Radiation therapy is an established cornerstone in the treatment of prostate cancer. Significant advances in the techniques and therapeutic concepts have been made in recent decades. OBJECTIVES The objective of this article is to provide an overview of current standards of care and recent technical and conceptional developments. CONCLUSIONS Three-dimensional conformal radiotherapy has long been the standard of care for percutaneous radiotherapy. The development of intensity-modulated radiation therapy (IMRT) and image-guided radiation therapy (IGRT) have increased the precision of treatment, thus, reducing side effects and allowing dose escalation. LDR (low dose rate) and HDR (high dose rate) brachytherapy alone or in combination are a treatment option in localized prostate cancer with a distinct side effect profile. The roles of proton therapy and stereotactic radiotherapy should be further investigated in prospective trials.
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Affiliation(s)
- M Grimm
- Klinik für Strahlentherapie und Radioonkologie, Universitätsmedizin Mannheim, Theodor-Kutzer-Ufer 1-3, 68135, Mannheim, Deutschland.
| | - F Wenz
- Klinik für Strahlentherapie und Radioonkologie, Universitätsmedizin Mannheim, Theodor-Kutzer-Ufer 1-3, 68135, Mannheim, Deutschland
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Katayama H, Ookubo M, Tsuzuki M, Sasakawa Y, Takahashi S, Shibata T. [Impact of Pelvic Rotational Setup Error on Lymph Nodal Dose in Whole Pelvic IMRT Using Fiducial Markers]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2016; 72:1152-1160. [PMID: 27867176 DOI: 10.6009/jjrt.2016_jsrt_72.11.1152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
PURPOSE The aim of this study was to investigate the impact of pelvic rotational setup error on lymph nodal dose in the whole pelvic intensity-modulated radiation therapy using the fiducial marker. METHODS The dose differences of clinical target volume for pelvic lymph node (CTVLN) due to isocenter (IC) shift and pelvic rotation were evaluated using the radiation treatment planning system. The rotated computed tomography (CT) images were created for the simulation of the pelvic rotation. The original CT images were rotated around the IC of the original plan in the pitch and roll directions up to±3.0 deg. at 1.0 deg. intervals. As simulated plans, IC positions were shifted in the anterior-posterior and superior-inferior directions up to±10 mm at 2 mm intervals in the original and rotated CT images, and the dose distributions were calculated. The dose calculation was performed for each CT image while keeping the movement of multi leaf collimator and the monitor unit of the original plan. The differences between D98% of CTVLN in the original plan and simulated plans were calculated. RESULTS In the posterior direction shifts of 4, 6, 8, and 10 mm, the dose reduction of 0.7, 2.1, 6.1, and 11.9% from the original plan were found for D98% of CTVLN, respectively. The dose reductions due to the rotation of pitch direction were greater than the rotation of roll direction. In the posterior direction shifts of 4, 6, 8, and 10 mm with 3.0 deg. rotation of pitch direction, the dose reduction of 2.2, 6.8, 12.8, and 19.0% from the original plan were found, respectively. CONCLUSION The dose reduction of CTVLN might be occurred due to the rotational setup error of pitch direction.
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Affiliation(s)
- Hiroki Katayama
- Department of Clinical Radiology, Kagawa University Hospital
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Law G, Leung R, Lee F, Luk H, Lee KC, Wong F, Wong M, Cheung S, Lee V, Mui WH, Chan M. Effectiveness of a Patient-Specific Immobilization and Positioning System to Limit Interfractional Translation and Rotation Setup Errors in Radiotherapy of Prostate Cancers. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/ijmpcero.2016.53020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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A Prospective Comparison of the Effects of Interfractional Variations on Proton Therapy and Intensity Modulated Radiation Therapy for Prostate Cancer. Int J Radiat Oncol Biol Phys 2015; 95:444-453. [PMID: 26907917 DOI: 10.1016/j.ijrobp.2015.12.366] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/24/2015] [Accepted: 12/21/2015] [Indexed: 11/21/2022]
Abstract
PURPOSE To quantify and compare the impact of interfractional setup and anatomic variations on proton therapy (PT) and intensity modulated radiation therapy (IMRT) for prostate cancer. METHODS AND MATERIALS Twenty patients with low-risk or intermediate-risk prostate cancer randomized to receive passive-scattering PT (n=10) and IMRT (n=10) were selected. For both modalities, clinical treatment plans included 50.4 Gy(RBE) to prostate and proximal seminal vesicles, and prostate-only boost to 79.2 Gy(RBE) in 1.8 Gy(RBE) per fraction. Implanted fiducials were used for prostate localization and endorectal balloons were used for immobilization. Patients in PT and IMRT arms received weekly computed tomography (CT) and cone beam CT (CBCT) scans, respectively. The planned dose was recalculated on each weekly image, scaled, and mapped onto the planning CT using deformable registration. The resulting accumulated dose distribution over the entire treatment course was compared with the planned dose using dose-volume histogram (DVH) and γ analysis. RESULTS The target conformity index remained acceptable after accumulation. The largest decrease in the average prostate D98 was 2.2 and 0.7 Gy for PT and IMRT, respectively. On average, the mean dose to bladder increased by 3.26 ± 7.51 Gy and 1.97 ± 6.84 Gy for PT and IMRT, respectively. These values were 0.74 ± 2.37 and 0.56 ± 1.90 for rectum. Differences between changes in DVH indices were not statistically significant between modalities. All volume indices remained within the protocol tolerances after accumulation. The average pass rate for the γ analysis, assuming tolerances of 3 mm and 3%, for clinical target volume, bladder, rectum, and whole patient for PT/IMRT were 100/100, 92.6/99, 99.2/100, and 97.2/99.4, respectively. CONCLUSION The differences in target coverage and organs at risk dose deviations for PT and IMRT were not statistically significant under the guidelines of this protocol.
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Cantin A, Gingras L, Lachance B, Foster W, Goudreault J, Archambault L. Dosimetric evaluation of three adaptive strategies for prostate cancer treatment including pelvic lymph nodes irradiation. Med Phys 2015; 42:7011-21. [DOI: 10.1118/1.4935529] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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Maruoka S, Yoshioka Y, Isohashi F, Suzuki O, Seo Y, Otani Y, Akino Y, Takahashi Y, Sumida I, Ogawa K. Correlation between patients' anatomical characteristics and interfractional internal prostate motion during intensity modulated radiation therapy for prostate cancer. SPRINGERPLUS 2015; 4:579. [PMID: 26543714 PMCID: PMC4628000 DOI: 10.1186/s40064-015-1382-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 09/27/2015] [Indexed: 11/23/2022]
Abstract
Intensity modulated radiation therapy (IMRT) is one of a standard treatment for localized prostate cancer. Although lower complication is expected for smaller target margin, determination of optimal margin is important. For bony-structure based registration, internal prostate motion is the main factor determining the margin from clinical target volume to planning target volume. The purpose of this study was to measure interfractional internal motion of the prostate and to identity the factors which enlarge or reduce the margin, with special focus on patients’ anatomical characteristics. The 586 image sets of 16 patients acquired with megavoltage cone beam computed tomography were analyzed. For each patient, prostate shift in three directions was recorded for each fraction to calculate the required margin. Correlations between these values and patients’ anatomical characteristics were evaluated. The posteriorly required margin correlated positively with rectal volume and rectal mean area (p = 0.015 and p = 0.008), while random error in lateral, craniocaudal and anteroposterior direction correlated negatively (p = 0.014, 0.04 and 0.0026, respectively) with body mass index (BMI). In addition to the previously identified factor of distended rectum, BMI was newly identified as another significant factor influencing interfractional internal prostate motion.
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Affiliation(s)
- Shintaroh Maruoka
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Yasuo Yoshioka
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Fumiaki Isohashi
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Osamu Suzuki
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Yuji Seo
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Yuki Otani
- Kaizuka City Hospital, 3-10-20 Hori, Kaizuka, Osaka, 597-0015 Japan
| | - Yuichi Akino
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Yutaka Takahashi
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Iori Sumida
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Kazuhiko Ogawa
- Department of Radiation Oncology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871 Japan
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Gayou O, Colonias A. Imaging a moving lung tumor with megavoltage cone beam computed tomography. Med Phys 2015; 42:2347-53. [DOI: 10.1118/1.4917524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Kanakavelu N, Samuel EJJ. Assessment and evaluation of MV image guidance system performance in radiotherapy. Rep Pract Oncol Radiother 2015; 20:188-97. [PMID: 25949222 DOI: 10.1016/j.rpor.2015.01.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 08/19/2014] [Accepted: 01/15/2015] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND AIM The clinical use of imaging system in image guided radiotherapy (IGRT) necessitates performing periodic quality assurance of the system to be confident in applying corrections for patient set-up errors. We aim to develop and implement a quality assurance (QA) programme for megavoltage (MV) based image guidance system and assess its long term performance for a period of 3 years. MATERIALS AND METHODS Periodic QA tests were performed for the MV planar and cone beam computed tomography (CBCT) imaging system to assess the system safety, mechanical and geometrical accuracy, image quality and dose. The tests were performed using the equipment supplied by the manufacturer along with the image guidance system and using simple methods developed in-house. The test results were compared with expected or baseline values established during commissioning. RESULTS The safety system was found to be functional. The results of mechanical and geometrical tests were in good agreement with the expected results. The system mechanical positioning was stable and reproducible within ±2 mm accuracy. The image quality and the imaging dose of the planar and CBCT imaging were found to agree with the baseline values and the manufacturer specifications. DISCUSSION Throughout the three-year period, all the QA tests were within the specification. The mechanical and geometrical tests are most crucial as they directly affect the patient positioning accuracy. CONCLUSION We conclude that the MV image guidance system is efficient to perform IGRT and insist to perform periodic QA tests and calibration for the system.
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Affiliation(s)
- Nithya Kanakavelu
- Department of Radiation Oncology, Medwin Cancer Center, Hyderabad, India ; Photonics, Nuclear and Medical Physics Division, VIT University, Vellore, India
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Maund IF, Benson RJ, Fairfoul J, Cook J, Huddart R, Poynter A. Image-guided radiotherapy of the prostate using daily CBCT: the feasibility and likely benefit of implementing a margin reduction. Br J Radiol 2014; 87:20140459. [PMID: 25354015 DOI: 10.1259/bjr.20140459] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To investigate whether planning target volume (PTV) margins may be safely reduced in radiotherapy of localized prostate cancer incorporating daily online tube potential-cone beam CT (CBCT) image guidance and the anticipated benefit in predicted rectal toxicity. METHODS The prostate-only clinical target volume (CTV2) and rectum were delineated on 1 pre-treatment CBCT each week in 18 randomly selected patients. By transposing these contours onto the original plan, dose-volume histograms (DVHs) for CTV2 and the rectum were each calculated and combined, for each patient, to produce a single mean DVH representative of the dose delivered over the treatment course. Plans were reoptimized using reduced CTV2 to PTV2 margins and the consequent radiobiological impact modelled by the tumour control probability (TCP) and normal tissue complication probability (NTCP) of the rectum. RESULTS All CBCT images were deemed of sufficient quality to identify the CTV and rectum. No loss of TCP was observed when plans using the standard 5-mm CTV2 to PTV2 margin of the centre were reoptimized with a 4- or 3-mm margin. Margin reduction was associated with a significant decrease in rectal NTCP (5-4 mm; p < 0.05 and 5-3 mm; p < 0.01). CONCLUSION Using daily online image guidance with CBCT, a reduction in CTV2 to PTV2 margins to 3 mm is achievable without compromising tumour control. The consequent sparing of surrounding normal tissues is associated with reduced anticipated rectal toxicity. ADVANCES IN KNOWLEDGE Margin reduction is feasible and potentially beneficial. Centres with image-guided radiotherapy capability should consider assessing whether margin reduction is possible within their institutes.
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Affiliation(s)
- I F Maund
- 1 Oncology Centre, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
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Scaife J, Harrison K, Romanchikova M, Parker A, Sutcliffe M, Bond S, Thomas S, Freeman S, Jena R, Bates A, Burnet N. Random variation in rectal position during radiotherapy for prostate cancer is two to three times greater than that predicted from prostate motion. Br J Radiol 2014; 87:20140343. [PMID: 25138155 PMCID: PMC4170867 DOI: 10.1259/bjr.20140343] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Objective: Radiotherapy for prostate cancer does not explicitly take into account daily variation in the position of the rectum. It is important to accurately assess accumulated dose (DA) to the rectum in order to understand the relationship between dose and toxicity. The primary objective of this work was to quantify systematic (Σ) and random (σ) variation in the position of the rectum during a course of prostate radiotherapy. Methods: The rectum was manually outlined on the kilo-voltage planning scan and 37 daily mega-voltage image guidance scans for 10 participants recruited to the VoxTox study. The femoral heads were used to produce a fixed point to which all rectal contours were referenced. Results: Σ [standard deviation (SD) of means] between planning and treatment was 4.2 mm in the anteroposterior (AP) direction and 1.3 mm left–right (LR). σ (root mean square of SDs) was 5.2 mm AP and 2.7 mm LR. Superior–inferior variation was less than one slice above and below the planning position. Conclusion: Our results for Σ are in line with published data for prostate motion. σ, however, was approximately twice as great as that seen for prostate motion. This suggests that DA may differ from planned dose in some patients treated with radiotherapy for prostate cancer. Advances in knowledge: This work is the first to use daily imaging to quantify Σ and σ of the rectum in prostate cancer. σ was found to be greater than published data, providing strong rationale for further investigation of individual DA.
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Affiliation(s)
- J Scaife
- 1 Department of Oncology, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
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Ikeda I, Mizowaki T, Sawada Y, Nakata M, Norihisa Y, Ogura M, Hiraoka M. Assessment of interfractional prostate motion in patients immobilized in the prone position using a thermoplastic shell. JOURNAL OF RADIATION RESEARCH 2014; 55:168-174. [PMID: 23860549 PMCID: PMC3885122 DOI: 10.1093/jrr/rrt089] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 06/06/2013] [Accepted: 06/08/2013] [Indexed: 06/02/2023]
Abstract
The aim of this study was to evaluate the interfractional prostate motion of patients immobilized in the prone position using a thermoplastic shell. A total of 24 patients with prostate calcifications detectable using a kilo-voltage X-ray image-guidance system (ExacTrac X-ray system) were examined. Daily displacements of the calcification within the prostate relative to pelvic bony structures were calculated by the ExacTrac X-ray system. The average displacement and standard deviation (SD) in each of the left-right (LR), anterior-posterior (AP), and superior-inferior (SI) directions were calculated for each patient. Based on the results of interfractional prostate motion, we also calculated planning target volume (PTV) margins using the van Herk formula and examined the validity of the PTV margin of our institute (a 9-mm margin everywhere except posteriorly, where a 6-mm margin was applied). In total, 899 data measurements from 24 patients were obtained. The average prostate displacements ± SD relative to bony structures were 2.8 ± 3.3, -2.0 ± 2.0 and 0.2 ± 0.4 mm, in the SI, AP and LR directions, respectively. The required PTV margins were 9.7, 6.1 and 1.4 mm in the SI, AP and LR directions, respectively. The clinical target volumes of 21 patients (87.5%) were located within the PTV for 90% or more of all treatment sessions. Interfractional prostate motion in the prone position with a thermoplastic shell was equivalent to that reported for the supine position. The PTV margin of our institute is considered appropriate for alignment, based on bony structures.
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Affiliation(s)
- Itaru Ikeda
- Department of Radiation Oncology and Image-applied Therapy, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Takashi Mizowaki
- Department of Radiation Oncology and Image-applied Therapy, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Yohei Sawada
- Division of Clinical Radiology Service, Kyoto University Hospital, 54 ShogoinKawahara-cho,Sakyo-ku, Kyoto 606-8507, Japan
| | - Manabu Nakata
- Division of Clinical Radiology Service, Kyoto University Hospital, 54 ShogoinKawahara-cho,Sakyo-ku, Kyoto 606-8507, Japan
| | - Yoshiki Norihisa
- Department of Radiation Oncology and Image-applied Therapy, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Masakazu Ogura
- Department of Radiation Oncology and Image-applied Therapy, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Masahiro Hiraoka
- Department of Radiation Oncology and Image-applied Therapy, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
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Interfractional variability in intensity-modulated radiotherapy of prostate cancer with or without thermoplastic pelvic immobilization. Strahlenther Onkol 2013; 190:94-9. [PMID: 24343757 DOI: 10.1007/s00066-013-0452-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 08/05/2013] [Indexed: 10/26/2022]
Abstract
PURPOSE To determine the variability of patient positioning errors associated with intensity-modulated radiotherapy (IMRT) for prostate cancer and to assess the impact of thermoplastic pelvic immobilization on these errors using kilovoltage (kV) cone-beam computed tomography (CBCT). MATERIALS AND METHODS From February 2012 to June 2012, the records of 314 IMRT sessions in 19 patients with prostate cancer, performed with or without immobilization at two different facilities in the Korea University Hospital were analyzed. The kV CBCT images were matched to simulation computed tomography (CT) images to determine the simulation-to-treatment variability. The shifts along the x (lateral)-, y (longitudinal)- and z (vertical)-axes were measured, as was the shift in the three dimensional (3D) vector. RESULTS The measured systematic errors in the immobilized group during treatment were 0.46 ± 1.75 mm along the x-axis, - 0.35 ± 3.83 mm along the y-axis, 0.20 ± 2.75 mm along the z-axis and 4.05 ± 3.02 mm in the 3D vector. Those of nonimmobilized group were - 1.45 ± 7.50 mm along the x-axis, 1.89 ± 5.07 mm along the y-axis, 0.28 ± 3.81 mm along the z-axis and 8.90 ± 4.79 mm in the 3D vector. The group immobilized with pelvic thermoplastics showed reduced interfractional variability along the x- and y-axes and in the 3D vector compared to the nonimmobilized group (p < 0.05). CONCLUSION IMRT with thermoplastic pelvic immobilization in patients with prostate cancer appears to be useful in stabilizing interfractional variability during the planned treatment course.
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Foster R, Meyer J, Iyengar P, Pistenmaa D, Timmerman R, Choy H, Solberg T. Localization Accuracy and Immobilization Effectiveness of a Stereotactic Body Frame for a Variety of Treatment Sites. Int J Radiat Oncol Biol Phys 2013; 87:911-6. [DOI: 10.1016/j.ijrobp.2013.09.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 09/10/2013] [Accepted: 09/12/2013] [Indexed: 10/26/2022]
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Yahya S, Zarkar A, Southgate E, Nightingale P, Webster G. Which bowel preparation is best? Comparison of a high-fibre diet leaflet, daily microenema and no preparation in prostate cancer patients treated with radical radiotherapy to assess the effect on planned target volume shifts due to rectal distension. Br J Radiol 2013; 86:20130457. [PMID: 23995876 PMCID: PMC3830438 DOI: 10.1259/bjr.20130457] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 08/26/2013] [Accepted: 08/28/2013] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE We evaluated and compared a high-fibre diet leaflet, daily microenema and no preparation to establish how best to achieve consistent bowel preparation in prostate cancer patients being treated with radical radiotherapy. METHODS 3 cohorts of 10 patients had different dietary interventions: no bowel preparation, high-fibre diet information leaflet and daily microenemas. The available cone beam CT (CBCT) scans of each patient were used to quantify interfractional changes in rectal distension (measured using average cross-sectional area-CSA), prostate shifts relative to bony anatomy compared with that at CT planning scan and rates of geometric miss (i.e. shifts of ≥5 mm). 85 CBCT scans were available in the pre-leaflet cohort, 89 scans in the post-leaflet, and 89 scans in the post-enema group. RESULTS Mean rectal CSA in the post-enema group was reduced compared with both pre-leaflet (p=0.010) and post-leaflet values (p=0.031). The magnitude of observed mean prostate shifts was significantly reduced in the post-enema group compared with the pre-leaflet group (p=0.014). The proportion of scans showing geometric miss (i.e. shift >5 mm) in the post-enema group (31%) was significantly lower than in the pre-leaflet (62%, p<0.001) or post-leaflet groups (56%, p<0.001). CONCLUSION This study indicates microenema to be an effective measure to achieve reduction in rectal CSA, prostate shift and reduce geometric miss of ≥5 mm. A further prospective randomised study is advocated to validate the results. ADVANCES IN KNOWLEDGE The use of microenema is effective in reducing prostate shift and rectal CSA, consequently decreasing the incidence of geographical miss.
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Affiliation(s)
- S Yahya
- Hall-Edwards Radiotherapy Research Group, The Cancer Centre, Queen Elizabeth Hospital, Birmingham, UK
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Ruciński A, Bauer J, Campbell P, Brons S, Unholtz D, Habl G, Herfarth K, Debus J, Bert C, Parodi K, Jäkel O, Haberer T. Preclinical investigations towards the first spacer gel application in prostate cancer treatment during particle therapy at HIT. Radiat Oncol 2013; 8:134. [PMID: 23742233 PMCID: PMC3698149 DOI: 10.1186/1748-717x-8-134] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 05/24/2013] [Indexed: 11/30/2022] Open
Abstract
Background The application of spacer gel represents a promising approach to reliably spare the rectal frontal wall during particle therapy (IJROBP 76:1251-1258, 2010). In order to qualify the spacer gel for the clinical use in particle therapy, a variety of measurements were performed in order to ensure the biological compatibility of the gel, its physical stability during and after the irradiation, and a proper definition of the gel in terms of the Hounsfield Unit (HU) values for the treatment planning system. The potential for the use of the spacer gel for particle therapy monitoring with off-line Positron Emission Tomography (PET) was also investigated. Results The spacer gel implanted to the prostate patient in direct neighbourhood to the clinical target volume does not interfere with the particle therapy treatment planning procedure applied at Heidelberg Ion Beam Therapy Centre (HIT). The performed measurements show that Bragg-peak position of the particles can be properly predicted on the basis of computed tomography imaging with the treatment planning system used at HIT (measured water equivalent path length of 1.011 ±0.011 (2σ), measured Hounsfield Unit of 28.9 ±6.1 (2σ)). The spacer gel samples remain physically unchanged after irradiation with a dose exceeding the therapeutic dose level. The independently measured Bragg-Peak position does not change within the time interval of 10 weeks. Conclusions As a result of the presented experiments, the first clinical application of spacer gel implant during prostate cancer treatment with carbon ions and protons was possible at HIT in 2012. The reported pre-clinical investigations demonstrate that use of spacer gel is safe in particle therapy in presence of therapy target motion and patient positioning induced particle range variations. The spacer gel injected between prostate and rectum enlarge the distance between both organs, which is expected to clinically significantly decrease the undesirable exposure of the most critical organ at risk, i.e. rectal frontal wall. Further research on the composition of spacer gel material might lead to additional clinical benefits by validation of particle therapy of prostate via post-therapeutic PET-imaging or by patient positioning based on the gel as a radio-opaque marker.
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Affiliation(s)
- Antoni Ruciński
- Heidelberg Ion Beam Therapy Center and Department of Radiation Oncology, Heidelberg University Clinic, Im Neuenheimer Feld 400, Heidelberg 69120, Germany.
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Postprostatectomy ultrasound-guided transrectal implantation of gold markers for external beam radiotherapy. Technique and complications rate. Strahlenther Onkol 2013; 189:476-81. [PMID: 23604186 DOI: 10.1007/s00066-013-0323-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 01/23/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND AND PURPOSE Postprostatectomy radiotherapy (RT) improves survival in adjuvant and salvage settings. The implantation technique and complications rate of gold markers in the prostate bed for high-precision RT were analyzed. PATIENTS AND METHODS Patients undergoing postprostatectomy RT for prostate-specific antigen (PSA) relapse or high-risk disease were enrolled in the study. Under transrectal ultrasound guidance, three fine gold markers were implanted in the prostate bed and the technical difficulties of insertion were documented. Patients received our self-designed questionnaires concerning complications and pain. The influence of anticoagulants and coumarins on bleeding was analyzed, as was the effect of potential risk factors on pain. RESULTS In 77 consecutive patients, failure of marker implantation or marker migration was seen in six cases. Rectal bleeding was reported by 10 patients and 1 had voiding complaints. No macroscopic hematuria persisting for more than 3 days was observed. Other complications included rectal discomfort (n = 2), nausea (n = 1), abdominal discomfort (n = 1), and pain requiring analgesics (n = 4). No major complications were reported. On a 0-10 visual analogue scale (VAS), the mean pain score was 3.7. No clinically significant risk factors for complications were identified. CONCLUSION Transrectal implantation of gold markers in the prostate bed is feasible and safe. Alternatives like cone beam computed tomography (CBCT) should be considered, but the advantages of gold marker implantation for high-precision postprostatectomy RT would seem to outweigh the minor risks involved.
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Jia MX, Zhang X, Li N, Han CB. Impact of different CBCT imaging monitor units, reconstruction slice thicknesses, and planning CT slice thicknesses on the positioning accuracy of a MV-CBCT system in head-and-neck patients. J Appl Clin Med Phys 2012; 13:3766. [PMID: 22955643 PMCID: PMC5718243 DOI: 10.1120/jacmp.v13i5.3766] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Revised: 06/05/2012] [Accepted: 06/04/2012] [Indexed: 11/23/2022] Open
Abstract
The purpose of this study was to investigate the impact of different CBCT imaging monitor units (MUs), reconstruction slice thicknesses, and planning CT slice thicknesses on the positioning accuracy of a megavoltage cone-beam computed tomography (MV-CBCT) system in image-guided radiation therapy (IGRT) in head-and-neck patients. The MV-CBCT system was a Siemens MVision, a commercial system integrated into the Siemens ONCOR linear accelerator. The positioning accuracy of the MV-CBCT system was determined using an anthropomorphic phantom while varying the MV-CBCT imaging MU, reconstruction slice thickness, and planning CT slice thickness. A total of 240 CBCT images from six head-and-neck patients who underwent intensity-modulated radiotherapy (IMRT) treatment were acquired and reconstructed using different MV-CBCT scanning protocols. The interfractional setup errors of the patients were retrospectively analyzed for different imaging MUs, reconstruction slice thicknesses, and planning CT slice thicknesses. Using the anthropomorphic phantom, the largest measured mean deviation component and standard deviation of the MVision in 3D directions were 1.3 and 1.0 mm, respectively, for different CBCT imaging MUs, reconstruction slice thicknesses, and planning CT slice thicknesses. The largest setup group system error (M), system error (Σ), and random error (σ) from six head-and-neck patients were 0.6, 1.2, and 1.7 mm, respectively. No significant difference was found in the positioning accuracy of the MV-CBCT system between the 5 and 8 MUs, and between the 1 and 3 mm reconstruction slice thicknesses. A thin planning CT slice thickness may achieve higher positioning precision using the phantom measurement, but no significant difference was found in clinical setup precision between the 1 and 3 mm planning CT slice thicknesses.
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Affiliation(s)
- Ming X Jia
- Department of Radiation Oncology, Shengjing Hospital of China Medial University, Shenyang 110022, China.
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Jia MX, Zhang X, Li N, Wang EY, Liu DW, Cai WS. Peripheral dose from megavoltage cone-beam CT imaging for nasopharyngeal carcinoma image-guided radiation therapy. J Appl Clin Med Phys 2012; 13:3869. [PMID: 22955655 PMCID: PMC5718218 DOI: 10.1120/jacmp.v13i5.3869] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 04/25/2012] [Accepted: 04/12/2012] [Indexed: 11/23/2022] Open
Abstract
The growing use of cone-beam computed tomography (CBCT) for IGRT has increased concerns over the additional radiation dose to patients. The in-field dose of IGRT and the peripheral dose (PD) from kilovoltage CBCT (KV-CBCT) imaging have been well quantified. The purpose of this work is to evaluate the peripheral dose from megavoltage CBCT (MV-CBCT) imaging for nasopharyngeal carcinoma IGRT, to determine the correlation of peripheral dose with MU protocol and imaging field size, and to estimate out-of-field organ-at-risk (OAR) dose delivered to patients. Measurements of peripheral MV-CBCT doses were made with a 0.65 cm(3) ionization chamber placed inside in a specially designed phantom at various depths and distances from the imaging field edges. The peripheral dose at reference point inside the phantom was measured with the same ionization chamber to investigate the linearity between MUs used for MV-CBCT imaging and the PD. The peripheral surface doses at the anterior, lateral, and posterior of the phantom at various distances from the imaging field edge were also measured with thermoluminescent dosimeters (TLDs). Seven nasopharyngeal carcinoma patients were selected and scanned before treatment with head-neck protocol, and the peripheral surface doses were measured with TLDs placed on the anterior, lateral, and posterior surfaces at the axial plane of 15 cm distance from the field edge. The measured peripheral doses data in the phantom were utilized to estimate the peripheral OAR dose. Peripheral dose from MV-CBCT imaging increased with increasing number of MUs used for imaging protocol and with increasing the imaging field size. The measured peripheral doses in the phantom decreased as distance from the imaging field edges increased. PD also decreased as the depth from the phantom surface increased. For the patient PD measurements, the anterior, lateral, and posterior surface doses of 15 cm distance from the field edge were 2.84 × 10(-2), 1.01 × 10(-2), and 0.78 × 10(-2) cGy/MU, respectively. The lens, thyroid, breast, and ovary and testicle, which are outside the treatment and imaging fields, were estimated to receive peripheral OAR doses from MV-CBCT imaging of 42.4 × 10(-2), 11.9 × 10(-2), 1.4 × 10(-2), 1.0 × 10(-2), and 0.5 × 10(-2) cGy/MU, respectively. In conclusion, MV-CBCT generates a peripheral dose beyond the edge of the MV-CBCT scanning field that is of a similar order of magnitude to the peripheral dose from kV-CBCT imaging. In clinic, using the smallest number of MUs allowable and reducing MV-CBCT scanning field size without compromising acquired image quality is an effective method of reducing the peripheral OAR dose received by patients.
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Affiliation(s)
- Ming X Jia
- Department of Radiation Oncology, Shengjing Hospital of China Medical University, Shenyang, China.
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