1
|
De Silva K, Brown A, Edwards C. Impact of transperineal ultrasound on perineal skin dose in prostate radiation therapy. Tech Innov Patient Support Radiat Oncol 2022; 23:27-32. [PMID: 36090010 PMCID: PMC9460562 DOI: 10.1016/j.tipsro.2022.08.003] [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: 06/10/2022] [Revised: 08/09/2022] [Accepted: 08/15/2022] [Indexed: 12/03/2022] Open
Abstract
Introduction This study investigated the relationship between anatomical compression introduced via ultrasound probe pressure and maximum perineum dose in prostate radiotherapy patients using the Clarity transperineal ultrasound (TPUS) system. Methods 115 patient ultrasound and computed tomography scans were retrospectively analysed. The probe to prostate apex distance (PPA), probe to inferior corpus spongiosum distance (PICS) and maximum perineum dose were calculated. Compression was represented by the PICS and the calculated corpus to prostate ratio (CPR). Demographics included treatment technique, image quality, body mass index (BMI) and age. Multiple linear regression analysis assessed the relationship between compression measures and perineum dose. Results The maximum dose to perineum ranged from 1.81 to 45.56 Gy, with a median of 5.87 Gy (Interquartile range (IQR) 3.17). The PICS distance and CPR recorded was 1.67 cm (IQR 0.63) and 0.51 (range 0.29-0.85) respectively. Regression analysis demonstrated both PICS and CPR were significant predictors of maximum dose to the perineum (p < 0.001). Patient-specific factors, including age, BMI, treatment technique and ultrasound image quality, were not factors that significantly impacted the maximum perineum dose. Conclusion There was a statistically significant association between increased anatomical compression and perineal dose measurements. A PICS of 1.2 cm or greater is recommended, with compression reduced as much as possible without losing anatomical US definition. Future investigations would be beneficial to evaluate the optimal balance between ultrasound image quality and transducer compression considering the perineum dose.
Collapse
Affiliation(s)
- Kalani De Silva
- School of Clinical Sciences, Queensland University of Technology, Gardens Point Campus, Brisbane, QLD, Australia
| | - Amy Brown
- Townsville University Hospital, Townsville, Queensland, Australia
| | - Christopher Edwards
- School of Clinical Sciences, Queensland University of Technology, Gardens Point Campus, Brisbane, QLD, Australia
| |
Collapse
|
2
|
Shanker MD, Kim AN, Brown A, Tan AH. Anatomical and dosimetric assessment of the prostate apex: A pilot comparison of image-guided transperineal ultrasound to conventional computed tomography simulation. J Med Imaging Radiat Oncol 2020; 64:839-844. [PMID: 32383303 DOI: 10.1111/1754-9485.13045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 04/09/2020] [Accepted: 04/14/2020] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Inaccuracies in prostate apex contour delineation based on simulation computed tomography (CT) imaging can impact treatment outcomes and toxicity profiles for prostate cancer radiotherapy. Transperineal ultrasound (TPUS) is a non-invasive imaging modality that can improve delineation of prostate volumes. We performed a pilot analysis to assess for differences in anatomical position between conventional CT and a TPUS delineated prostate apex and determined whether these translated into a clinically significant difference in apical point dose. METHODS A 2D 5 MHz TPUS autoscan image guidance system was utilised during definitive intensity-modulated radiotherapy (IMRT) for prostate cancer. Distances were measured from a fixed reference point to prostate apex on both US and CT in the mid-sagittal plane. Differences between groups were assessed using the Wilcoxon sign rank test with a two-tailed significance of α = 0.05. RESULTS Fifty-nine consecutive patients were independently assessed. There was strong evidence of a difference between CT and TPUS delineated apex position (P = 0.0075). Median apex position was 3.6 mm caudal on TPUS vs. CT imaging (95% CI: 2.5-4.8 mm). There was strong evidence of a difference in point dose between CT and TPUS delineated apex (P = 0.0029). Median point dose at the TPUS contoured apex was 1.9 Gy lower than CT (95% CI: 0.7-3.1 Gy) corresponding to 98% of prescribed dose. CONCLUSIONS This study demonstrates a difference in anatomical delineation of prostate apex position between CT imaging compared to TPUS, corresponding to a statistically significant difference in apex point dose. Further analysis will determine whether this translates to a clinically significant difference in outcomes.
Collapse
Affiliation(s)
- Mihir D Shanker
- Queensland Health, Brisbane, Queensland, Australia.,Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - Anna Nh Kim
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia.,ICON Cancer Centre, Brisbane, Queensland, Australia
| | - Amy Brown
- Queensland Health, Brisbane, Queensland, Australia.,Townsville Cancer Centre, Townsville Hospital and Health Service, Queensland, Australia.,James Cook University, Townsville, Queensland, Australia
| | - Alex Hm Tan
- Queensland Health, Brisbane, Queensland, Australia.,Townsville Cancer Centre, Townsville Hospital and Health Service, Queensland, Australia.,James Cook University, Townsville, Queensland, Australia
| |
Collapse
|
3
|
Richter A, Exner F, Weick S, Lawrenz I, Polat B, Flentje M, Mantel F. Evaluation of intrafraction prostate motion tracking using the Clarity Autoscan system for safety margin validation. Z Med Phys 2020; 30:135-141. [DOI: 10.1016/j.zemedi.2019.12.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 11/18/2019] [Accepted: 12/11/2019] [Indexed: 02/08/2023]
|
4
|
Pang EPP, Knight K, Fan Q, Tan SXF, Ang KW, Master Z, Mui WH, Leung RWK, Baird M, Tuan JKL. Analysis of intra-fraction prostate motion and derivation of duration-dependent margins for radiotherapy using real-time 4D ultrasound. PHYSICS & IMAGING IN RADIATION ONCOLOGY 2018; 5:102-107. [PMID: 33458378 PMCID: PMC7807728 DOI: 10.1016/j.phro.2018.03.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 03/15/2018] [Accepted: 03/15/2018] [Indexed: 12/02/2022]
Abstract
Investigates the magnitude of intra-fraction prostate motion using real time monitoring. A motion-time trend analysis was presented. A duration-dependent margin was recommended. Larger margins are required around the prostate in the inferior and posterior directions.
Background and purpose During radiotherapy, prostate motion changes over time. Quantifying and accounting for this motion is essential. This study aimed to assess intra-fraction prostate motion and derive duration-dependent planning margins for two treatment techniques. Material and methods A four-dimension (4D) transperineal ultrasound Clarity® system was used to track prostate motion. We analysed 1913 fractions from 60 patients undergoing volumetric-modulated arc therapy (VMAT) to the prostate. The mean VMAT treatment duration was 3.4 min. Extended monitoring was conducted weekly to simulate motion during intensity-modulated radiation therapy (IMRT) treatment (an additional seven minutes). A motion-time trend analysis was conducted and the mean intra-fraction motion between VMAT and IMRT treatments compared. Duration-dependent margins were calculated and anisotropic margins for VMAT and IMRT treatments were derived. Results There were statistically significant differences in the mean intra-fraction motion between VMAT and the simulated IMRT duration in the inferior (0.1 mm versus 0.3 mm) and posterior (−0.2 versus −0.4 mm) directions respectively (p ≪ 0.01). An intra-fraction motion trend inferiorly and posteriorly was observed. The recommended minimum anisotropic margins are 1.7 mm/2.7 mm (superior/inferior); 0.8 mm (left/right), 1.7 mm/2.9 mm (anterior/posterior) for VMAT treatments and 2.9 mm/4.3 mm (superior/inferior), 1.5 mm (left/right), 2.8 mm/4.8 mm (anterior/posterior) for IMRT treatments. Smaller anisotropic margins were required for VMAT compared to IMRT (differences ranging from 1.2 to 1.6 mm superiorly/inferiorly, 0.7 mm laterally and 1.1–1.9 mm anteriorly/posteriorly). Conclusions VMAT treatment is preferred over IMRT as prostate motion increases with time. Larger margins should be employed in the inferior and posterior directions for both treatment durations. Duration-dependent margins should be applied in the presence of prolonged imaging and verification time.
Collapse
Affiliation(s)
- Eric Pei Ping Pang
- Division of Radiation Oncology, National Cancer Centre Singapore, 11 Hospital Drive, Singapore 169610, Singapore
- Faculty of Medicine, Nursing and Health Sciences, Department of Medical Imaging & Radiation Sciences, Monash University, Wellington Road, Clayton, VIC 3800, Australia
- Corresponding author at: Division of Radiation Oncology, National Cancer Centre Singapore, 11 Hospital Drive, Singapore 169610, Singapore.
| | - Kellie Knight
- Faculty of Medicine, Nursing and Health Sciences, Department of Medical Imaging & Radiation Sciences, Monash University, Wellington Road, Clayton, VIC 3800, Australia
| | - Qiao Fan
- Centre for Quantitative Medicine, Duke-NUS Medical School, 8 College Road, Singapore 169857, Singapore
| | - Sheena Xue Fei Tan
- Division of Radiation Oncology, National Cancer Centre Singapore, 11 Hospital Drive, Singapore 169610, Singapore
| | - Khong Wei Ang
- Division of Radiation Oncology, National Cancer Centre Singapore, 11 Hospital Drive, Singapore 169610, Singapore
| | - Zubin Master
- Division of Radiation Oncology, National Cancer Centre Singapore, 11 Hospital Drive, Singapore 169610, Singapore
| | - Wing-Ho Mui
- Tuen Mun Hospital, 23 Tsing Chung Koon Road, Tuen Mun, New Territories, Hong Kong
| | | | - Marilyn Baird
- Faculty of Medicine, Nursing and Health Sciences, Department of Medical Imaging & Radiation Sciences, Monash University, Wellington Road, Clayton, VIC 3800, Australia
| | - Jeffrey Kit Loong Tuan
- Division of Radiation Oncology, National Cancer Centre Singapore, 11 Hospital Drive, Singapore 169610, Singapore
- Duke-NUS Graduate Medical School, 8 College Road, Singapore 169857, Singapore
| |
Collapse
|
5
|
The Use of Ultrasound Imaging in the External Beam Radiotherapy Workflow of Prostate Cancer Patients. BIOMED RESEARCH INTERNATIONAL 2018; 2018:7569590. [PMID: 29619375 PMCID: PMC5829356 DOI: 10.1155/2018/7569590] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 12/13/2017] [Accepted: 12/28/2017] [Indexed: 12/16/2022]
Abstract
External beam radiotherapy (EBRT) is one of the curative treatment options for prostate cancer patients. The aim of this treatment option is to irradiate tumor tissue, while sparing normal tissue as much as possible. Frequent imaging during the course of the treatment (image guided radiotherapy) allows for determination of the location and shape of the prostate (target) and of the organs at risk. This information is used to increase accuracy in radiation dose delivery resulting in better tumor control and lower toxicity. Ultrasound imaging is harmless for the patient, it is cost-effective, and it allows for real-time volumetric organ tracking. For these reasons, it is an ideal technique for image guidance during EBRT workflows. Review papers have been published in which the use of ultrasound imaging in EBRT workflows for different cancer sites (prostate, breast, etc.) was extensively covered. This new review paper aims at providing the readers with an update on the current status for prostate cancer ultrasound guided EBRT treatments.
Collapse
|
6
|
Richter A, Polat B, Lawrenz I, Weick S, Sauer O, Flentje M, Mantel F. Initial results for patient setup verification using transperineal ultrasound and cone beam CT in external beam radiation therapy of prostate cancer. Radiat Oncol 2016; 11:147. [PMID: 27825386 PMCID: PMC5101794 DOI: 10.1186/s13014-016-0722-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 10/27/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Evaluation of set up error detection by a transperineal ultrasound in comparison with a cone beam CT (CBCT) based system in external beam radiation therapy (EBRT) of prostate cancer. METHODS Setup verification was performed with transperineal ultrasound (TPUS) and CBCT for 10 patients treated with EBRT for prostate cancer. In total, 150 ultrasound and CBCT scans were acquired in rapid succession and analyzed for setup errors. The deviation between setup errors of the two modalities was evaluated separately for each dimension. RESULTS A moderate correlation in lateral, vertical and longitudinal direction was observed comparing the setup errors. Mean differences between TPUS and CBCT were (-2.7 ± 2.3) mm, (3.0 ± 2.4) mm and (3.2 ± 2.7) mm in lateral, vertical and longitudinal direction, respectively. The mean Euclidean difference between TPUS and CBCT was (6.0 ± 3.1) mm. Differences up to 19.2 mm were observed between the two imaging modalities. Discrepancies between TPUS and CBCT of at least 5 mm occurred in 58 % of monitored treatment sessions. CONCLUSION Setup differences between TPUS and CBCT are 6 mm on average. Although the correlation of the setup errors determined by the two different image modalities is rather week, the combination of setup verification by CBCT and intrafraction motion monitoring by TPUS imaging can use the benefits of both imaging modalities.
Collapse
Affiliation(s)
- Anne Richter
- Department of Radiation Oncology, University of Wuerzburg, Josef-Schneider-Str. 11, 97080, Wuerzburg, Germany.
| | - Bülent Polat
- Department of Radiation Oncology, University of Wuerzburg, Josef-Schneider-Str. 11, 97080, Wuerzburg, Germany
| | - Ingulf Lawrenz
- Department of Radiation Oncology, University of Wuerzburg, Josef-Schneider-Str. 11, 97080, Wuerzburg, Germany
| | - Stefan Weick
- Department of Radiation Oncology, University of Wuerzburg, Josef-Schneider-Str. 11, 97080, Wuerzburg, Germany
| | - Otto Sauer
- Department of Radiation Oncology, University of Wuerzburg, Josef-Schneider-Str. 11, 97080, Wuerzburg, Germany
| | - Michael Flentje
- Department of Radiation Oncology, University of Wuerzburg, Josef-Schneider-Str. 11, 97080, Wuerzburg, Germany
| | - Frederick Mantel
- Department of Radiation Oncology, University of Wuerzburg, Josef-Schneider-Str. 11, 97080, Wuerzburg, Germany
| |
Collapse
|