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Haslam P, Brown E, Burbery J, Hargrave C, Lee YY. To degas or not to degas? The effectiveness of pharmaceuticals in reducing the impact of bowel volume variations during liver SBRT treatment. J Med Radiat Sci 2024; 71:156-162. [PMID: 37584089 PMCID: PMC10920934 DOI: 10.1002/jmrs.714] [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] [Received: 01/09/2023] [Accepted: 07/28/2023] [Indexed: 08/17/2023] Open
Abstract
The indications for liver stereotactic body radiation therapy (SBRT) continue to expand in the management of liver cancer due to the improved rates of local control with acceptable normal tissue toxicity. Changes in internal anatomy, such as the bowel, may negatively impact the precision of treatment delivery of SBRT liver treatment by influencing daily image matching. Institutions have developed various approaches to promoting bowel volume consistency. One such strategy is the administration of pharmaceuticals. The administration of pharmaceuticals, such as Simethicone, has been adopted by the Princess Alexandra Hospital Radiation Oncology Department (ROPAIR) as a method to promote consistency in the amount of bowel gas observed in liver cancer patients. This case series examines a group of patients treated at ROPAIR with liver SBRT to determine whether current practices effectively reduce the impact of bowel volume variations for liver cancer patients. Initial observations from this hypothesis generating research suggest potential improved consistency of the small bowel's anatomical position for liver SBRT patients who were administered Simethicone (Bowel bag dice similarity coefficient - Simethicone group = 0.79-0.92, Standard group = 0.24-0.93). However, it appeared that this strategy alone may not be entirely effective achieving consistency in the amount of bowel gas present throughout the duration of treatment. Further investigation into the refinement of liver SBRT pre-treatment preparation is therefore recommended.
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Affiliation(s)
- Phoebe Haslam
- Queensland University of TechnologyFaculty of HealthSchool of Clinical SciencesBrisbaneQueenslandAustralia
- Radiation Oncology Princess Alexandra HospitalBrisbaneQueenslandAustralia
| | - Elizabeth Brown
- Queensland University of TechnologyFaculty of HealthSchool of Clinical SciencesBrisbaneQueenslandAustralia
- Radiation Oncology Princess Alexandra HospitalBrisbaneQueenslandAustralia
| | - Julie Burbery
- Queensland University of TechnologyFaculty of HealthSchool of Clinical SciencesBrisbaneQueenslandAustralia
| | - Catriona Hargrave
- Queensland University of TechnologyFaculty of HealthSchool of Clinical SciencesBrisbaneQueenslandAustralia
- Radiation Oncology Princess Alexandra HospitalRaymond TerraceBrisbaneQueenslandAustralia
| | - Yoo Young Lee
- Radiation Oncology Princess Alexandra HospitalBrisbaneQueenslandAustralia
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Ates O, Pirlepesov F, Uh J, Hua CH, Merchant TE, Boria A, Davidoff AM, Graetz DE, Krasin MJ. Evaluating the Impact of Bowel Gas Variations for Wilms' Tumor in Pediatric Proton Therapy. Cancers (Basel) 2024; 16:642. [PMID: 38339393 PMCID: PMC10854738 DOI: 10.3390/cancers16030642] [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: 12/27/2023] [Revised: 01/27/2024] [Accepted: 01/31/2024] [Indexed: 02/12/2024] Open
Abstract
(1) Background: Proton therapy, a precise form of radiation treatment, can be significantly affected by variations in bowel content. The purpose was to identify the most beneficial gantry angles that minimize deviations from the treatment plan quality, thus enhancing the safety and efficacy of proton therapy for Wilms' tumor patients. (2) Methods: Thirteen patients with Wilms' tumor, enrolled in the SJWT21 clinical trial, underwent proton therapy. The variations in bowel gas were systematically monitored using daily Cone Beam Computed Tomography (CBCT) imaging. Air cavities identified in daily CBCT images were analyzed to construct daily verification plans and measure water equivalent path length (WEPL) changes. A worst-case scenario simulation was conducted to identify the safest beam angles. (3) Results: The study revealed a maximum decrease in target dose (ΔD100%) of 8.0%, which corresponded to a WEPL variation (ΔWEPL) of 11.3 mm. The average reduction in target dose, denoted as mean ΔD100%, was found to be 2.8%, with a standard deviation (SD) of 3.2%. The mean ΔWEPL was observed as 3.3 mm, with an SD of 2.7 mm. The worst-case scenario analysis suggested that gantry beam angles oriented toward the patient's right and posterior aspects from 110° to 310° were associated with minimized WEPL discrepancies. (4) Conclusions: This study comprehensively evaluated the influence of bowel gas variability on treatment plan accuracy and proton range uncertainties in pediatric proton therapy for Wilms' tumor.
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Affiliation(s)
- Ozgur Ates
- St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (F.P.); (J.U.); (C.-h.H.); (T.E.M.); (A.B.); (A.M.D.); (D.E.G.); (M.J.K.)
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3
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Wang E, Yen A, Hrycushko B, Wang S, Lin J, Zhong X, Dohopolski M, Nwachukwu C, Iqbal Z, Albuquerque K. The accuracy of artificial intelligence deformed nodal structures in cervical online cone-beam-based adaptive radiotherapy. Phys Imaging Radiat Oncol 2024; 29:100546. [PMID: 38369990 PMCID: PMC10869256 DOI: 10.1016/j.phro.2024.100546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 01/31/2024] [Accepted: 02/01/2024] [Indexed: 02/20/2024] Open
Abstract
Background and Purpose Online cone-beam-based adaptive radiotherapy (ART) adjusts for anatomical changes during external beam radiotherapy. However, limited cone-beam image quality complicates nodal contouring. Despite this challenge, artificial-intelligence guided deformation (AID) can auto-generate nodal contours. Our study investigated the optimal use of such contours in cervical online cone-beam-based ART. Materials and Methods From 136 adaptive fractions across 21 cervical cancer patients with nodal disease, we extracted 649 clinically-delivered and AID clinical target volume (CTV) lymph node boost structures. We assessed geometric alignment between AID and clinical CTVs via dice similarity coefficient, and 95% Hausdorff distance, and geometric coverage of clinical CTVs by AID planning target volumes by false positive dice. Coverage of clinical CTVs by AID contour-based plans was evaluated using D100, D95, V100%, and V95%. Results Between AID and clinical CTVs, the median dice similarity coefficient was 0.66 and the median 95 % Hausdorff distance was 4.0 mm. The median false positive dice of clinical CTV coverage by AID planning target volumes was 0. The median D100 was 1.00, the median D95 was 1.01, the median V100% was 1.00, and the median V95% was 1.00. Increased nodal volume, fraction number, and daily adaptation were associated with reduced clinical CTV coverage by AID-based plans. Conclusion In one of the first reports on pelvic nodal ART, AID-based plans could adequately cover nodal targets. However, physician review is required due to performance variation. Greater attention is needed for larger, daily-adapted nodes further into treatment.
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Affiliation(s)
- Ethan Wang
- University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, TX, United States
| | - Allen Yen
- University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, TX, United States
| | - Brian Hrycushko
- University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, TX, United States
| | - Siqiu Wang
- University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, TX, United States
| | - Jingyin Lin
- University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, TX, United States
| | - Xinran Zhong
- University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, TX, United States
| | - Michael Dohopolski
- University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, TX, United States
| | - Chika Nwachukwu
- University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, TX, United States
| | - Zohaib Iqbal
- University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, TX, United States
| | - Kevin Albuquerque
- University of Texas Southwestern Medical Center, Department of Radiation Oncology, Dallas, TX, United States
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4
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Taylor S, Lim P, Cantwell J, D’Souza D, Moinuddin S, Chang YC, Gaze MN, Gains J, Veiga C. Image guidance and interfractional anatomical variation in paediatric abdominal radiotherapy. Br J Radiol 2023; 96:20230058. [PMID: 37102707 PMCID: PMC10230397 DOI: 10.1259/bjr.20230058] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 04/28/2023] Open
Abstract
OBJECTIVES To identify variables predicting interfractional anatomical variations measured with cone-beam CT (CBCT) throughout abdominal paediatric radiotherapy, and to assess the potential of surface-guided radiotherapy (SGRT) to monitor these changes. METHODS Metrics of variation in gastrointestinal (GI) gas volume and separation of the body contour and abdominal wall were calculated from 21 planning CTs and 77 weekly CBCTs for 21 abdominal neuroblastoma patients (median 4 years, range: 2 - 19 years). Age, sex, feeding tubes, and general anaesthesia (GA) were explored as predictive variables for anatomical variation. Furthermore, GI gas variation was correlated with changes in body and abdominal wall separation, as well as simulated SGRT metrics of translational and rotational corrections between CT/CBCT. RESULTS GI gas volumes varied 74 ± 54 ml across all scans, while body and abdominal wall separation varied 2.0 ± 0.7 mm and 4.1 ± 1.5 mm from planning, respectively. Patients < 3.5 years (p = 0.04) and treated under GA (p < 0.01) experienced greater GI gas variation; GA was the strongest predictor in multivariate analysis (p < 0.01). Absence of feeding tubes was linked to greater body contour variation (p = 0.03). GI gas variation correlated with body (R = 0.53) and abdominal wall (R = 0.63) changes. The strongest correlations with SGRT metrics were found for anterior-posterior translation (R = 0.65) and rotation of the left-right axis (R = -0.36). CONCLUSIONS Young age, GA, and absence of feeding tubes were linked to stronger interfractional anatomical variation and are likely indicative of patients benefiting from adaptive/robust planning pathways. Our data suggest a role for SGRT to inform the need for CBCT at each treatment fraction in this patient group. ADVANCES IN KNOWLEDGE This is the first study to suggest the potential role of SGRT for the management of internal interfractional anatomical variation in paediatric abdominal radiotherapy.
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Affiliation(s)
- Sabrina Taylor
- University College London, Centre for Medical Image Computing, London, United Kingdom
| | - Pei Lim
- Department of Oncology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Jessica Cantwell
- Radiotherapy, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Derek D’Souza
- Radiotherapy, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Syed Moinuddin
- Radiotherapy, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Yen-Ching Chang
- Department of Oncology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Mark N Gaze
- Department of Oncology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Jennifer Gains
- Department of Oncology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Catarina Veiga
- University College London, Centre for Medical Image Computing, London, United Kingdom
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5
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Szmul A, Taylor S, Lim P, Cantwell J, Moreira I, Zhang Y, D’Souza D, Moinuddin S, Gaze MN, Gains J, Veiga C. Deep learning based synthetic CT from cone beam CT generation for abdominal paediatric radiotherapy. Phys Med Biol 2023; 68:105006. [PMID: 36996837 PMCID: PMC10160738 DOI: 10.1088/1361-6560/acc921] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 03/13/2023] [Accepted: 03/30/2023] [Indexed: 04/01/2023]
Abstract
Objective. Adaptive radiotherapy workflows require images with the quality of computed tomography (CT) for re-calculation and re-optimisation of radiation doses. In this work we aim to improve the quality of on-board cone beam CT (CBCT) images for dose calculation using deep learning.Approach. We propose a novel framework for CBCT-to-CT synthesis using cycle-consistent Generative Adversarial Networks (cycleGANs). The framework was tailored for paediatric abdominal patients, a challenging application due to the inter-fractional variability in bowel filling and small patient numbers. We introduced to the networks the concept of global residuals only learning and modified the cycleGAN loss function to explicitly promote structural consistency between source and synthetic images. Finally, to compensate for the anatomical variability and address the difficulties in collecting large datasets in the paediatric population, we applied a smart 2D slice selection based on the common field-of-view (abdomen) to our imaging dataset. This acted as a weakly paired data approach that allowed us to take advantage of scans from patients treated for a variety of malignancies (thoracic-abdominal-pelvic) for training purposes. We first optimised the proposed framework and benchmarked its performance on a development dataset. Later, a comprehensive quantitative evaluation was performed on an unseen dataset, which included calculating global image similarity metrics, segmentation-based measures and proton therapy-specific metrics.Main results. We found improved performance for our proposed method, compared to a baseline cycleGAN implementation, on image-similarity metrics such as Mean Absolute Error calculated for a matched virtual CT (55.0 ± 16.6 HU proposed versus 58.9 ± 16.8 HU baseline). There was also a higher level of structural agreement for gastrointestinal gas between source and synthetic images measured using the dice similarity coefficient (0.872 ± 0.053 proposed versus 0.846 ± 0.052 baseline). Differences found in water-equivalent thickness metrics were also smaller for our method (3.3 ± 2.4% proposed versus 3.7 ± 2.8% baseline).Significance. Our findings indicate that our innovations to the cycleGAN framework improved the quality and structure consistency of the synthetic CTs generated.
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Affiliation(s)
- Adam Szmul
- Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London, United Kingdom
| | - Sabrina Taylor
- Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Pei Lim
- Department of Oncology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Jessica Cantwell
- Radiotherapy, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Isabel Moreira
- Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Ying Zhang
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Derek D’Souza
- Radiotherapy Physics Services, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Syed Moinuddin
- Radiotherapy, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Mark N. Gaze
- Department of Oncology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Jennifer Gains
- Department of Oncology, University College London Hospitals NHS Foundation Trust, London, United Kingdom
| | - Catarina Veiga
- Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
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Kusano Y, Katoh H, Minohara S, Fujii H, Miyasaka Y, Takayama Y, Imura K, Kusunoki T, Miyakawa S, Kamada T, Serizawa I, Takakusagi Y, Mizoguchi N, Tsuchida K, Yoshida D. Robust treatment planning in scanned carbon-ion radiotherapy for pancreatic cancer: Clinical verification using in-room computed tomography images. Front Oncol 2022; 12:974728. [PMID: 36106121 PMCID: PMC9465304 DOI: 10.3389/fonc.2022.974728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 08/03/2022] [Indexed: 11/13/2022] Open
Abstract
PurposeCarbon-ion beam (C-beam) has a sharp dose distribution called the Bragg peak. Carbon-ion radiation therapy, such as stereotactic body radiotherapy in photon radiotherapy, can be completed in a short period by concentrating the radiation dose on the tumor while minimizing the dose to organs at-risk. However, the stopping position of C-beam is sensitive to density variations along the beam path and such variations can lower the tumor dose as well as cause the delivery of an unexpectedly high dose to the organs at risk. We evaluated the clinical efficacy of a robust planning technique considering gastrointestinal gas (G-gas) to deliver accurate radiation doses in carbon-ion radiotherapy for pancreatic cancer.Materials and methodsWe focused on the computed tomography (CT) value replacement method. Replacement signifies the overwriting of CT values in the CT images. The most effective replacement method for robust treatment planning was determined by verifying the effects of the three replacement patterns. We selected 10 consecutive patients. Pattern 1 replaces the CT value of the G-gas contours with the value of the region without G-gas (P1). This condition indicates a no-gas state. Pattern 2 replaces each gastrointestinal contour using the mean CT value of each contour (P2). The effect of G-gas was included in the replacement value. Pattern 3 indicates no replacement (P3). We analyzed variations in the target coverage (TC) and homogeneity index (HI) from the initial plan using in-room CT images. We then performed correlation analysis on the variations in G-gas, TC, and HI to evaluate the robustness against G-gas.ResultsAnalysis of variations in TC and HI revealed a significant difference between P1 and P3 and between P2 and P3. Although no statistically significant difference was observed between P1 and P2, variations, including the median, tended to be fewer in P2. The correlation analyses for G-gas, TC, and HI showed that P2 was less likely to be affected by G-gas.ConclusionFor a treatment plan that is robust to G-gas, P2 mean replacement method should be used. This method does not necessitate any particular software or equipment, and is convenient to implement in clinical practice.
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Affiliation(s)
- Yohsuke Kusano
- Section of Medical Physics and Engineering, Kanagawa Cancer Center, Yokohama, Japan
- *Correspondence: Yohsuke Kusano,
| | - Hiroyuki Katoh
- Department of Radiation Oncology, Kanagawa Cancer Center, Yokohama, Japan
| | - Shinichi Minohara
- Section of Medical Physics and Engineering, Kanagawa Cancer Center, Yokohama, Japan
| | - Hajime Fujii
- Accelerator Engineering Corporation, Kanagawa Office, Chiba, Japan
| | - Yuya Miyasaka
- Department of Heavy Particle Medical Science, Yamagata University Graduate School of Medical Science, Yamagata, Japan
| | - Yoshiki Takayama
- Section of Medical Physics and Engineering, Kanagawa Cancer Center, Yokohama, Japan
| | - Koh Imura
- Section of Medical Physics and Engineering, Kanagawa Cancer Center, Yokohama, Japan
| | - Terufumi Kusunoki
- Section of Medical Physics and Engineering, Kanagawa Cancer Center, Yokohama, Japan
| | - Shin Miyakawa
- Section of Medical Physics and Engineering, Kanagawa Cancer Center, Yokohama, Japan
| | - Tadashi Kamada
- Department of Radiation Oncology, Kanagawa Cancer Center, Yokohama, Japan
| | - Itsuko Serizawa
- Department of Radiation Oncology, Kanagawa Cancer Center, Yokohama, Japan
| | - Yosuke Takakusagi
- Department of Radiation Oncology, Kanagawa Cancer Center, Yokohama, Japan
| | - Nobutaka Mizoguchi
- Department of Radiation Oncology, Kanagawa Cancer Center, Yokohama, Japan
| | - Keisuke Tsuchida
- Department of Radiation Oncology, Kanagawa Cancer Center, Yokohama, Japan
| | - Daisaku Yoshida
- Department of Radiation Oncology, Kanagawa Cancer Center, Yokohama, Japan
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7
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Liang Y, Feng S, Xie W, Jiang Q, Yang Y, Luo R, Kidd EA, Zhai T, Xie L. Comparison of survival, acute toxicities, and dose-volume parameters between intensity-modulated radiotherapy with or without internal target volume delineation method and three-dimensional conformal radiotherapy in cervical cancer patients: A retrospective and propensity score-matched analysis. Cancer Med 2022; 11:151-165. [PMID: 34821082 PMCID: PMC8704157 DOI: 10.1002/cam4.4439] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 09/25/2021] [Accepted: 10/26/2021] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND To evaluate whether the use of the internal target volume (ITV) delineation method improves the performance of intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3DCRT) in terms of survival, acute toxicities, and dose-volume parameters. METHODS A total number of 477 cervical cancer patients who received concurrent chemoradiotherapy (CCRT) from January 2012 to December 2016 were retrospectively analyzed. They were divided into four groups: the non-ITV (N-ITV) + IMRT, ITV + IMRT, N-ITV + 3DCRT, and ITV + 3DCRT groups, with 76, 41, 327, and 33 patients, respectively. Survival analysis was performed with the Kaplan-Meier and the log-rank tests, and acute toxicity analysis was performed with the chi-squared test and the binary logistic regression test. Using the propensity score matching (PSM) method, 92 patients were matched among the four groups, and their dose-volume parameters were assessed with the Kruskal-Wallis method. RESULTS The median follow-up time was 49 months (1-119) for overall survival (OS). The 5-year OS rate was 66.4%. The ITV delineation method was an independent prognostic factor for OS (HR [95% CI]: 0.52 [0.27, 0.98], p = 0.044) and progression-free survival (PFS) (HR [95% CI]: 0.59 [0.36, 0.99], p = 0.045). The ITV + IMRT group had the lowest incidence rate (22%) and the N-ITV + IMRT group had the highest incidence rate of grade ≥3 hematological toxicity (HT) (46.1%) among the four groups. The pelvic bone marrow relative V10, V20, and V30 in the N-ITV + IMRT group was higher than those in the ITV + IMRT and N-ITV + 3DCRT groups (p < 0.05). CONCLUSIONS The use of ITV for IMRT treatment planning was associated with improved overall survival and progression-free survival, with lower HT rate.
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Affiliation(s)
- Yu‐Qin Liang
- Department of Radiation Oncology, Xiang’an Hospital of Xiamen University, Xiamen, China
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, China
| | - Sen‐Quan Feng
- Department of Radiation OncologyCancer Hospital of Shantou University Medical CollegeShantouChina
- Department of Radiation OncologyUniversity of GroningenUniversity Medical Center GroningenGroningenThe Netherlands
| | - Wen‐Jia Xie
- Department of Radiation OncologyXiang’an Hospital of Xiamen UniversityXiamenChina
- Department of Radiation OncologyCancer Hospital of Shantou University Medical CollegeShantouChina
| | - Qiong‐Zhi Jiang
- Department of Radiation OncologyCancer Hospital of Shantou University Medical CollegeShantouChina
| | - Yan‐Fen Yang
- Department of Science and EducationXiang’an Hospital of Xiamen UniversityXiamenChina
| | - Ren Luo
- Department of Radiation OncologyFaculty of MedicineUniversity of FreiburgFreiburgGermany
- Faculty of BiologyUniversity of FreiburgFreiburgGermany
| | - Elizabeth A. Kidd
- Department of Radiation OncologyStanford UniversityStanfordCaliforniaUSA
| | - Tian‐Tian Zhai
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, China
| | - Liang‐Xi Xie
- Department of Radiation Oncology, Xiang’an Hospital of Xiamen University, Xiamen, China
- Department of Radiation Oncology, Cancer Hospital of Shantou University Medical College, Shantou, China
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8
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Ricotti R, Pella A, Mirandola A, Fiore MR, Chalaszczyk A, Paganelli C, Antonioli L, Vai A, Tagaste B, Belotti G, Rossi M, Ciocca M, Orlandi E, Baroni G. Dosimetric effect of variable rectum and sigmoid colon filling during carbon ion radiotherapy to sacral chordoma. Phys Med 2021; 90:123-133. [PMID: 34628271 DOI: 10.1016/j.ejmp.2021.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 08/13/2021] [Accepted: 09/23/2021] [Indexed: 11/17/2022] Open
Abstract
PURPOSE Carbon ion radiotherapy (CIRT) is sensitive to anatomical density variations. We examined the dosimetric effect of variable intestinal filling condition during CIRT to ten sacral chordoma patients. METHODS For each patient, eight virtual computed tomography scans (vCTs) were generated by varying the density distribution within the rectum and the sigmoid in the planning computed tomography (pCT) with a density override approach mimicking a heterogeneous combination of gas and feces. Totally full and empty intestinal preparations were modelled. In addition, five different intestinal filling conditions were modelled by a mixed density pattern derived from two combined and weighted Gaussian distributions simulating gas and feces respectively. Finally, a patient-specific mixing proportion was estimated by evaluating the daily amount of gas detected in the cone beam computed tomography (CBCT). Dose distribution was recalculated on each vCT and dose volume histograms (DVHs) were examined. RESULTS No target coverage degradation was observed at different vCTs. Rectum and sigma dose degradation ranged respectively between: [-6.7; 21.6]GyE and [-0.7; 15.4]GyE for D50%; [-377.4; 1197.9] and [-95.2; 1027.5] for AUC; [-1.2; 10.7]GyE and [-2.6; 21.5]GyE for D1%. CONCLUSIONS Variation of intestinal density can greatly influence the penetration depth of charged particle and might compromise dose distribution. In particular cases, with large clinical target volume in very close proximity to rectum and sigmoid colon, it is appropriate to evaluate the amount of gas present in the daily CBCT images even if it is totally included in the reference planning structures.
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Affiliation(s)
- R Ricotti
- Bioengineering Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy.
| | - A Pella
- Bioengineering Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - A Mirandola
- Medical Physics Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - M R Fiore
- Radiation Oncology Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - A Chalaszczyk
- Radiation Oncology Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - C Paganelli
- Department of Electronics Information and Bioengineering, Politecnico di Milano, Milano, Italy
| | - L Antonioli
- Bioengineering Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - A Vai
- Medical Physics Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - B Tagaste
- Bioengineering Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - G Belotti
- Department of Electronics Information and Bioengineering, Politecnico di Milano, Milano, Italy
| | - M Rossi
- Department of Electronics Information and Bioengineering, Politecnico di Milano, Milano, Italy
| | - M Ciocca
- Medical Physics Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - E Orlandi
- Radiation Oncology Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - G Baroni
- Bioengineering Unit, Clinical Department, National Center for Oncological Hadrontherapy (CNAO), Pavia, Italy; Department of Electronics Information and Bioengineering, Politecnico di Milano, Milano, Italy
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9
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Busch K, Dahl B, Petersen SE, Rønde HS, Bentzen L, Pilskog S, Muren LP. Anatomically robust proton therapy using multiple planning computed tomography scans for locally advanced prostate cancer. Acta Oncol 2021; 60:598-604. [PMID: 33646069 DOI: 10.1080/0284186x.2021.1892181] [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: 10/22/2022]
Abstract
BACKGROUND Proton therapy (PT) is sensitive towards anatomical changes that may occur during a treatment course. The aim of this study was to investigate if anatomically robust PT (ARPT) plans incorporating patient-specific target motion improved target coverage while still sparing normal tissues, when applied on locally advanced prostate cancer patients where pelvic irradiation is indicated. MATERIAL AND METHODS A planning computed tomography (CT) scan used for dose calculation and two additional CTs (acquired on different days) were used to make patient-specific targets for the ARPT plans on the eight included patients. The plans were compared to a conventional robust PT plan and a volumetric modulated arc therapy (VMAT) photon plan, which were derived from the planning CT (pCT). Worst-case robust optimisation was used for all proton plans with a setup uncertainty of 5 mm and a range uncertainty of 3.5%. Target coverage (V95% and D95%) and normal tissue doses (V5-75 Gy) were evaluated on 6-8 rCTs per patient. RESULTS The ARPT plans improved the prostate target coverage for the most challenging patient compared to conventional robust PT plans (20% point increase for V95% and 31 Gy increase for D95%). Across the whole cohort the estimated mean value for V95% was 97% for the ARPT plans and 95% for the conventional robust PT plans. The ARPT plans had a slight, statistically insignificant increase in normal tissue doses compared to the conventional robust proton plans. Compared to VMAT, the ARPT plans significantly reduced the normal tissue doses in the low-to-intermediate dose range. CONCLUSIONS While both proton plans reduced the low-to-intermediate normal tissue doses compared to VMAT, ARPT plans improved the target coverage for the most challenging patient without significantly increasing the normal tissue doses compared to conventional robust PT plans.
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Affiliation(s)
- Kia Busch
- Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Benjamin Dahl
- Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
| | - Stine E. Petersen
- Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
| | - Heidi S. Rønde
- Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
| | - Lise Bentzen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Oncology, Aarhus University Hospital, Aarhus, Denmark
| | - Sara Pilskog
- Department of Physics and Technology, University of Bergen, Bergen, Norway
- Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen, Norway
| | - Ludvig P. Muren
- Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
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10
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Bjaanæs MM, Sande EPS, Loe Ø, Ramberg C, Næss TM, Ottestad A, Rogg LV, Svestad JG, Haakensen VD. Improved adaptive radiotherapy to adjust for anatomical alterations during curative treatment for locally advanced lung cancer. Phys Imaging Radiat Oncol 2021; 18:51-54. [PMID: 34258408 PMCID: PMC8254190 DOI: 10.1016/j.phro.2021.04.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 04/09/2021] [Accepted: 04/23/2021] [Indexed: 12/24/2022] Open
Abstract
Anatomical changes during chemoradiation for lung cancer may decrease dose to the target or increase dose to organs at risk. To assess our ability to identify clinically significant anatomical alterations, we followed 67 lung cancer patients by daily cone-beam CT scans to ensure correct patient positioning and observe anatomical alterations. We also re-calculated the original dose distribution on a planned control CT scan obtained halfway during the treatment course to identify anatomical changes that potentially affected doses to the target or organs at risk. Of 66 patients who completed the treatment, 12 patients needed adaptation, two patients were adapted twice. We conclude that daily cone-beam CT and routines at the treatment machine discover relevant anatomical changes during curative radiotherapy for patients with lung cancer without additional imaging.
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Affiliation(s)
| | | | - Øyvind Loe
- Dept of Oncology, Oslo University Hospital, Oslo, Norway
| | | | | | | | - Lotte V. Rogg
- Dept of Oncology, Oslo University Hospital, Oslo, Norway
| | | | - Vilde Drageset Haakensen
- Dept of Oncology, Oslo University Hospital, Oslo, Norway
- Dept of Cancer Genetics, Oslo University Hospital, Oslo, Norway
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11
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Niyoteka S, Berger T, Fokdal LU, Petersen JBB, Zolnay A, Hoogeman M, Tanderup K, Nystrom HU. Impact of interfractional target motion in locally advanced cervical cancer patients treated with spot scanning proton therapy using an internal target volume strategy. PHYSICS & IMAGING IN RADIATION ONCOLOGY 2021; 17:84-90. [PMID: 33898784 PMCID: PMC8058016 DOI: 10.1016/j.phro.2021.01.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 01/23/2021] [Accepted: 01/28/2021] [Indexed: 01/08/2023]
Abstract
Background and purpose The more localized dose deposition of proton therapy (PT) compared to photon therapy might allow a reduction in treatment-related side effects but induces additional challenges to address. The aim of this study was to evaluate the impact of interfractional motion on the target and organs at risk (OARs) in cervical cancer patients treated with spot scanning PT using an internal target volume (ITV) strategy. Methods and materials For ten locally advanced cervical cancer patients, empty and full bladder planning computed tomography (pCT) as well as 25 daily cone beam CTs (CBCTs) were available. The Clinical Target Volume (CTV), the High Risk CTV (CTVHR) (gross tumor volume and whole cervix), the non-involved uterus as well as the OARs (bowel, bladder and rectum) were contoured on the daily CBCTs and transferred to the pCT through rigid bony match. Using synthetic CTs derived from pCTs, four-beam spot scanning PT plans were generated to target the patient-specific ITV with 45 Gy(RBE) in 25 fractions. This structure was defined based on pre-treatment MRI and CT to anticipate potential target motion throughout the treatment. D98% of the targets and V40Gy(RBE) of the OARs were extracted from the daily anatomies, accumulated and analyzed. In addition, the impact of bladder volume deviations from planning values on target and bowel dose was investigated. Results The ITV strategy ensured a total accumulated dose >42.75 Gy(RBE) to the CTVHR for all ten patients. Two patients with large bladder-related uterus motion had accumulated dose to the non-involved uterus of 35.7 Gy(RBE) and 41.1 Gy(RBE). Variations in bowel V40Gy(RBE) were found to be correlated (Pearson r = −0.55; p-value <0.0001) with changes in bladder volume during treatment. Conclusion The ITV concept ensured adequate dose to the CTVHR, but was insufficient for the non-involved uterus of patients subject to large target interfractional motion. CBCT monitoring and occasional replanning is recommended along the same lines as with photon radiotherapy in cervical cancer.
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Affiliation(s)
| | - Thomas Berger
- Department of Oncology, Aarhus University Hospital, Aarhus, Denmark
| | | | | | - Andras Zolnay
- Erasmus MC Cancer Institute, University Medical Center Rotterdam, Department of Radiotherapy, The Netherlands
| | - Mischa Hoogeman
- Erasmus MC Cancer Institute, University Medical Center Rotterdam, Department of Radiotherapy, The Netherlands
- Holland PTC, Delft, The Netherlands
| | - Kari Tanderup
- Department of Oncology, Aarhus University Hospital, Aarhus, Denmark
- Corresponding author.
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12
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Yao W, Schweitzer N, Biswal N, Polf J, Farr J, Vujaskovic Z. Impact of bowel and rectum air on target dose with robustly optimized intensity-modulated proton therapy plans. Acta Oncol 2020; 59:1186-1192. [PMID: 32500780 DOI: 10.1080/0284186x.2020.1769859] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE Pelvic target dose from intensity-modulated proton therapy (IMPT) is sensitive to patient bowel motion. Robustly optimized plans in regard to bowel filling may improve the dose coverage in the treatment course. Our purpose is to investigate the effect of air volume in large and small bowel and rectum on target dose from IMPT plans. METHODS AND MATERIAL Data from 17 cancer patients (11 prostate, 3 gynecologic, 2 colon, and 1 embryonal rhabdomyosarcoma) with planning CT (pCT) and weekly or biweekly scanned quality assurance CTs (QACTs; 82 QACT scans total) were studied. Air in bowels and rectum traversed by proton pencil beams was contoured. The robust treatment plan was made by using 3 CT sets: the pCT set and 2 virtual CT sets that were copies of pCT but in which the fillings of bowels and rectum were overridden to be either air or muscle. Each plan had 2-5 beams with a mean of 3 beams. Targets in the pCT were mapped to the QACTs by deformable image registration, and the dose in QACTs was calculated. Dose coverage (D99 and D95) and correlations between dose coverage and changes in air volume were analyzed. The significance of the correlation was analyzed by t test. RESULTS Mean changes of D99 in QACTs were within 3% of those in the pCT for all prostate and colon cases but >3% in 2 of the 3 gynecologic cases and in the embryonal rhabdomyosarcoma case. Of these three cases with mean change of D99 > 3%, air volume may be the main cause in 2. For the prostate cases, correlation coefficients were <0.7 between change in air volume and change in D99 and D95, because other anatomy changes also contributed to dose deviation. Correlation coefficients in the non-prostate cases were >0.9 between D99 change and rectum and between D95 change and small bowel, indicating a greater effect of the air volume on target dose. CONCLUSION The air volume may still have an important effect on target dose coverage in treatment plans using 3 CT sets, particularly when the air is traversed by multiple beams.
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Affiliation(s)
- Weiguang Yao
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Noah Schweitzer
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Nrusingh Biswal
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jerimy Polf
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Jonathan Farr
- Applications of Detectors and Accelerators to Medicine, Meyrin, Switzerland
| | - Zeljko Vujaskovic
- Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD, USA
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Affiliation(s)
- Jens Overgaard
- Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark
| | - Ludvig Paul Muren
- Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark
| | - Morten Høyer
- Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
| | - Cai Grau
- Department of Oncology and Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
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Miura H, Ozawa S, Doi Y, Nakao M, Ohnishi K, Kenjo M, Nagata Y. Automatic gas detection in prostate cancer patients during image-guided radiation therapy using a deep convolutional neural network. Phys Med 2019; 64:24-28. [PMID: 31515026 DOI: 10.1016/j.ejmp.2019.06.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 06/04/2019] [Accepted: 06/17/2019] [Indexed: 12/29/2022] Open
Abstract
PURPOSE The detection of intestinal/rectal gas is very important during image-guided radiation therapy (IGRT) of prostate cancer patients because intestinal/rectal gas increases the inter- and intra-fractional prostate motion. We propose a deep convolutional neural network (DCNN) to detect intestinal/rectal gas in the pelvic region. MATERIAL AND METHODS We selected 300 anterior-posterior kilo-voltage (kV) X-ray images from 30 prostate cancer patients. Thirty images were randomly chosen for a test set, and the remaining 270 images used as the training set. The intestinal/rectal gas was manually delineated on kV X-ray images and segmented. The training images were augmented by applying artificial shifts and fed into a DCNN. The network models were trained to keep the quality of the output image close to the quality of the input image by pooling and upsampling. The training set was used to adjust the parameters of the DCNN, and the test set was used to assess the performance of the model. The performance of the DCNN was evaluated using a fivefold cross-validation procedure. The dice similarity coefficient (DSC) was calculated to evaluate the detection accuracy between the manual contour and auto-segmentation. RESULTS The DCNN was trained within approximately 17 min with a time step of 20 s/epoch. The training and validation accuracy of the models after 50epochs were 0.94 and 0.85, respectively. The average ± standard deviation of the DSC for 30 test images was 0.85 ± 0.08. CONCLUSIONS The proposed DCNN method can automatically detect the intestinal/rectal gas in kV images with good accuracy.
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Affiliation(s)
- Hideharu Miura
- Hiroshima High-Precision Radiotherapy Cancer Center, Hiroshima, Japan; Department of Radiation Oncology, Institute of Biomedical & Health Science, Hiroshima University, Hiroshima, Japan.
| | - Shuichi Ozawa
- Hiroshima High-Precision Radiotherapy Cancer Center, Hiroshima, Japan; Department of Radiation Oncology, Institute of Biomedical & Health Science, Hiroshima University, Hiroshima, Japan
| | - Yoshiko Doi
- Hiroshima High-Precision Radiotherapy Cancer Center, Hiroshima, Japan; Department of Radiation Oncology, Institute of Biomedical & Health Science, Hiroshima University, Hiroshima, Japan
| | - Minoru Nakao
- Hiroshima High-Precision Radiotherapy Cancer Center, Hiroshima, Japan; Department of Radiation Oncology, Institute of Biomedical & Health Science, Hiroshima University, Hiroshima, Japan
| | - Keiichi Ohnishi
- Hiroshima High-Precision Radiotherapy Cancer Center, Hiroshima, Japan
| | - Masahiro Kenjo
- Hiroshima High-Precision Radiotherapy Cancer Center, Hiroshima, Japan; Department of Radiation Oncology, Institute of Biomedical & Health Science, Hiroshima University, Hiroshima, Japan
| | - Yasushi Nagata
- Hiroshima High-Precision Radiotherapy Cancer Center, Hiroshima, Japan; Department of Radiation Oncology, Institute of Biomedical & Health Science, Hiroshima University, Hiroshima, Japan
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15
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Effect of setup and inter-fraction anatomical changes on the accumulated dose in CT-guided breath-hold intensity modulated proton therapy of liver malignancies. Radiother Oncol 2019; 134:101-109. [PMID: 31005203 DOI: 10.1016/j.radonc.2019.01.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 12/04/2018] [Accepted: 01/22/2019] [Indexed: 12/13/2022]
Abstract
PURPOSE To evaluate the effect of setup uncertainties including uncertainties between different breath holds (BH) and inter-fractional anatomical changes under CT-guided BH with intensity-modulated proton therapy (IMPT) in patients with liver cancer. METHODS AND MATERIALS This retrospective study considered 17 patients with liver tumors who underwent feedback-guided BH (FGBH) IMRT treatment with daily CT-on-rail imaging. Planning CT images were acquired at simulation using FGBH, and FGBH CT-on-rail images were also acquired prior to each treatment. Selective robust IMPT plans were generated using planning CT and re-calculated on each daily CT-on-rail image. Subsequently, the fractional doses were deformed and accumulated onto the planning CT according to the deformable image registration between daily and planning CTs. The doses to the target and organs at risk (OARs) were compared between IMRT, planned IMPT, and accumulated IMPT doses. RESULTS For IMPT plans, the mean of D98% of CTV for all 17 patients was slightly reduced from the planned dose of 68.90 ± 1.61 Gy to 66.48 ± 1.67 Gy for the accumulated dose. The target coverage could be further improved by adjusting planning techniques. The dose-volume histograms of both planned and accumulated IMPT doses showed better sparing of OARs than that of the IMRT. CONCLUSIONS IMPT with FGBH and CT-on-rail guidance is a robust treatment approach for liver tumor cases.
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Jin P, Crama KF, Visser J, van Wieringen N, Bel A, Hulshof MC, Alderliesten T. Density override in treatment planning to mitigate the dosimetric effect induced by gastrointestinal gas in esophageal cancer radiation therapy. Acta Oncol 2018; 57:1646-1654. [PMID: 30289340 DOI: 10.1080/0284186x.2018.1518590] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
PURPOSE To investigate the dosimetric effect of variable gas volume in esophageal cancer radiation therapy (RT) and whether a density override (DO) in treatment planning can effectively mitigate this dosimetric effect. MATERIAL AND METHODS Nine patients with gastrointestinal gas pockets in the planning computed tomography (pCT) were retrospectively included. Per patient, the intensity-modulated RT (IMRT) and volumetric-modulated arc therapy (VMAT) plans associated with no DO, DO = 0.5, and DO = 1 in the gas pockets were made. Initial and follow-up gas volumes were assessed from the pCTs and cone-beam CTs (CBCTs), respectively. Fractional CTs were created based on the pCT and CBCTs to calculate the fractional doses using all six plans. We then investigated for all six plans the correlation between the gas volume difference (relative to initial gas volume) and the dose difference (relative to planned dose). We also calculated and compared the accumulated dose by summing the fractional doses using two strategies: single-plan strategy (i.e. using each of the six plans separately) and plan-selection strategy (i.e. selecting one of the three plans depending on the fractional gas volume for IMRT and VMAT planning separately). RESULTS The dose difference was approximately linearly correlated to the gas volume difference. Underdoses of >3.5% and overdoses of >7% were found for gas volume decreases >160 mL/330 mL and increases >260 mL/370 mL for IMRT/VMAT planning, respectively. Moreover, for most patients, the single-plan strategy with the use of DO = 0.5 resulted in neither undesired underdose nor much overdose. The plan-selection strategy, however, can always ensure sufficient target coverage and minimize high dose regions to the most extent. CONCLUSIONS The variation in gas volume during the treatment course can result in clinically undesired underdose or overdose. The DO-based plan-selection strategy can effectively mitigate the gas-induced underdose and minimize the overdose for esophageal cancer RT.
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Affiliation(s)
- Peng Jin
- Department of Radiation Oncology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Koen F. Crama
- Department of Radiation Oncology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Jorrit Visser
- Department of Radiation Oncology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Niek van Wieringen
- Department of Radiation Oncology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Maarten C.C.M. Hulshof
- Department of Radiation Oncology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Tanja Alderliesten
- Department of Radiation Oncology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
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Intensity-modulated radiotherapy for whole pelvis irradiation in prostate cancer: A dosimetric and plan robustness study between photons and protons. Tech Innov Patient Support Radiat Oncol 2018; 6:11-19. [PMID: 32095573 PMCID: PMC7033791 DOI: 10.1016/j.tipsro.2018.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 02/16/2018] [Accepted: 02/22/2018] [Indexed: 11/22/2022] Open
Abstract
Purpose To evaluate the dosimetric impact and plan robustness of using Pencil Beam Scanning (PBS) in patients that requires prophylactic pelvic lymph nodes (PLNs) irradiation for prostate cancer. Material and methods Five intermediate to high-risk prostate patients previously treated using volumetric modulated arc therapy (VMAT), were selected for this study. Comparative proton radiotherapy plans were generated, where a three-field intensity modulated proton therapy (IMPT) plan was for the phase 1 planning target volume (PTV1) with PLNs. A technique with two posterior oblique fields using single field uniform dose (SFUD) was used for phase 2 (PTV2) volume, that comprises of the prostate and proximal seminal vesicles (Pro + proxSVs). Plan evaluation was performed on PTV coverage and dose to the organs at risk (OARs) using VMAT plans as a baseline (BL). Robust analysis on clinical target volume (CTV) coverage for the PBS plans was simulated with a 3 and 5 mm setup errors and a 3.5% range uncertainty. Results For target coverage, PTV1 and PTV2 showed negligible differences with a comparable homogeneity index (HI) values for both modalities. Proton plans produced a statistically significant lower mean dose to the bladder (32.5 Gy(RBE) vs. 46.5 Gy) and rectum (33.6 Gy(RBE) vs. 42.7 Gy). Dose to the bladder and rectum was equivalent at the high dose region. For the bowel cavity, the mean dose for proton plans were 45% lower compared to VMAT plans. Similarly, proton plans were able to achieve an overall reduction in integral dose for both treatment phase. CTV coverage remained high with all the simulated setup and range errors. Conclusions Proposed beam geometries for PTV1 and PTV2 proton plans presented good treatment accuracy with similar target coverage as the VMAT plans. Better sparing of OARs was achieved at the low-medium dose region for the proton plans.
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