BrachytherapyPub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.136
Suman Gautam, Alexander F. I Osman, Dylan Richerson, Binod Manandhar, Sharmin Alam, William Y. Song
{"title":"PO35","authors":"Suman Gautam, Alexander F. I Osman, Dylan Richerson, Binod Manandhar, Sharmin Alam, William Y. Song","doi":"10.1016/j.brachy.2023.06.136","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.136","url":null,"abstract":"Purpose The purpose of this work is to develop a voxel-wise dose prediction system using convolutional neural network (CNN) for cervical cancer high-dose-rate (HDR) intracavitary brachytherapy treatment planning with tandem-and-ovoid (T&O) or tandem-and-ring (T&R) applicators. Materials and Methods A 3D U-NET CNN was implemented to generate voxel-wise dose predictions based on high-risk clinical target volume (HRCTV) and organs at risk (OAR) contour information. A multi-institutional cohort of 77 retrospective clinical HDR brachytherapy plans treated to a prescription dose in the range of 4.8-7.0 Gy/fx was used in this study. Those plans were randomly divided into 60%/20%/20% as training, validating, and testing cohorts. Data augmentation techniques like flip diagonally, flip left and right, flipping up and down, and rotating 90 degrees were implemented in the training and validation cohort data to increase the number of plans to 252. The model was trained using the mean-squared loss function, Adam optimization algorithm, a learning rate of 0.001, 250 epochs, and a batch size of 8. The model performance was evaluated on the testing dataset by analyzing the outcomes in terms of maximum dose values and derived dose-volume-histogram (DVH) indices from 3D dose distributions and comparing the generated dose distributions against the ground-truth dose distributions using dose statistics and clinically meaningful dosimetric indices. Results The proposed 3D U-Net model showed competitive accuracy in predicting 3D dose distributions that closely resemble the ground truth dose distributions. The average value of mean absolute error was 0.108±3.617 Gy for HRCTV, 0.074±1.315 Gy for bladder, 0.093±0.981 Gy for rectum, and 0.035±2.789 Gy for sigmoid. The median absolute error was 0.126 Gy for HRCTV, 0.041 Gy for the bladder, 0.0013 Gy for rectum, and 0.019 Gy for sigmoid. Our results showed that the predicted mean D2cc OAR doses in the bladder, rectum, sigmoid were 3.51±1.25, 3.11±1.23 and 4.02±2.23 Gy in comparison to 4.21±1.23, 4.20±1.02, 4.80±1.59 Gy in clinical plans respectively. The predicted D90 of the HRCTV was 6.72±0.99 Gy in comparison with 6.83±1.72 Gy in clinical plans. The predicted maximum dose to bladder, sigmoid, and rectum were 7.51±1.10, 3.81±1.27, 3.61±1.16 Gy in comparison to 7.33±1.03, 4.66±2.06, 4.33±1.75 Gy in clinical plans, respectively, indicating a good potential to predict useful dosimetric indices and facilitate an improvement in brachytherapy treatment workflow. The proposed model needs less than 5 seconds to predict a full 3D dose distribution of 64 × 64 × 64 voxels for any new patient plan, thus making it sufficient for near real-time applications and aid in decision-making in clinic. Conclusions The 3D U-Net model we have implemented demonstrates competitive capability in predicting accurate dose distributions and DVH indices with consistent quality. The proposed model can be used to predict 3D dose distributions for near real-","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BrachytherapyPub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.198
Abigail Dare, Zachary Horne
{"title":"PO97","authors":"Abigail Dare, Zachary Horne","doi":"10.1016/j.brachy.2023.06.198","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.198","url":null,"abstract":"Purpose To compare dosimetric values for interstitial HDR brachytherapy cases using both manual and inverse planning techniques and refine optimization results for clinical use. Materials and Methods Ten plans for prior interstitial brachytherapy were selected for analysis representing a variety of treatments: Elekta's Venezia applicator with needles (4), Best Medical's Syed/Neblett gynecological template (3), and Best Medical's prostate template (3). Each plan, previously manually optimized (MO), was optimized in Oncentra (Elekta) using both IPSA and HIPO inverse planning algorithms. For the first plan of each type, optimization parameters were iteratively adjusted from comparison to the MO treated plan. The parameters were then saved as a template to apply to future plans of the same type. Dosimetric quantities were recorded for each optimization type for comparison. For the optimized cases, the metrics collected were clinically relevant values representing target coverage and OAR constraints. Results For target coverage (HRCTV D90%), IPSA produced lower coverage on average for Venezia (-15.5%) and Syed (-0.2%) cases when compared to the MO plan and higher for prostate (4.3%). HIPO resulted in higher coverage for Venezia (1.3%) and prostate (1.5%) and lower for Syed (-0.7%). OAR doses were assessed normalized to HRCTV D90% equal to prescription dose. IPSA had lower OAR metrics on average for Syed (-8.3%) and prostate (-3.2%) and higher for Venezia (0.1%). HIPO gave lower OAR metrics for Venezia (-1.9%) and Syed (-4.2%) and higher for prostate (2.2%). Conclusions Overall, HIPO was more consistent in comparable or improved results to the clinically treated MO plan. Treatment planning time for clinical interstitial cases has reduced, and we have adopted a hybrid optimization approach starting with HIPO inverse optimization and then performing manual changes as needed. Future work includes refining optimization parameters to be globally applicable for each treatment type and warrant less manual optimization. To compare dosimetric values for interstitial HDR brachytherapy cases using both manual and inverse planning techniques and refine optimization results for clinical use. Ten plans for prior interstitial brachytherapy were selected for analysis representing a variety of treatments: Elekta's Venezia applicator with needles (4), Best Medical's Syed/Neblett gynecological template (3), and Best Medical's prostate template (3). Each plan, previously manually optimized (MO), was optimized in Oncentra (Elekta) using both IPSA and HIPO inverse planning algorithms. For the first plan of each type, optimization parameters were iteratively adjusted from comparison to the MO treated plan. The parameters were then saved as a template to apply to future plans of the same type. Dosimetric quantities were recorded for each optimization type for comparison. For the optimized cases, the metrics collected were clinically relevant values representing target coverag","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BrachytherapyPub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.207
Irina Vasilievna Horot
{"title":"PO106","authors":"Irina Vasilievna Horot","doi":"10.1016/j.brachy.2023.06.207","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.207","url":null,"abstract":"Ways of the treatment of non-melanomas skin cancer are still under discussion. Recurrences after different modalities usage are still high. It applies to surgery, external irradiation and brachytherapy. Using brachytherapy, we can achieve very high local doses. Moreover, they can be higher, the lower the volume of irradiation. In this sense, brachytherapy has its own characteristics that greatly distinguish it from other approaches, but there are still many unresolved questions in brachytherapy itself. For example, irradiating the tumor with an application method or with injection applicators into the tumor, how to normalize the dose, adhering to the prescribed restrictions. Purpose The aim of the work was to compare the results of three brachytherapy methods in non melanoma skin cancer. Patients and Methods We work at Microselectron, 30 channels. Planning of the isodose distribution is based on CT scans. 370 patients have been treated since 2012. Essential is the question of how many applicators to use and how to distribute them spatially. We use all available methods - iron needles and flexible applicators for interstitial brachytherapy, as well as application methods with individual masks and individual applicator placement. We use boluses to equalize the dose and the arrangement of applicators in several rows. A change in the location of the applicators changes something in the dose distribution that can be used to improve the distribution. That is, for example, to increase the dose value at the center of the tumor and increase the dose-fall gradient at the edges. When we use the applicator method with an individual mask our doses amounted to 36 Gy, 6 Gy, 6 fractions 5 times per week. The normalization of the dose depends on the tumor size, location and some other parameters. In the case of rigid needles insertion we prescribe 8 Gy twice per week, 4 fractions, total dose is equal to 32 Gy. In the case of intratissue irradiation with flexible applicators the total dose is equal to 42.5 Gy, 5.2 Gy, 8 fractions 5 times per week. Interstitial method is used as a rule in the case of volumetric tumors. Results Using iron needles has several advantages - extraction of needles takes place immediately after the delivery of dose in every fraction. The swelling disappears during one hour after extraction, and wound healing after irradiation happens faster. It is especially significant in treating eyelids. However, all three methods are comparable in results when the dose is properly normalized. Conclusion We came to the conclusion that the choice of the method of irradiation, as well as the normalization of the dose in brachytherapy for non-melanoma skin cancer, depends mainly on the characteristics of the tumor and its location. Ways of the treatment of non-melanomas skin cancer are still under discussion. Recurrences after different modalities usage are still high. It applies to surgery, external irradiation and brachytherapy. Using brachytherapy, we ","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BrachytherapyPub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.212
Juan Wang, Yansong Liang, Zezhou Liu, Hongtao Zhang
{"title":"PO111","authors":"Juan Wang, Yansong Liang, Zezhou Liu, Hongtao Zhang","doi":"10.1016/j.brachy.2023.06.212","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.212","url":null,"abstract":"There is no one-size-fits-all treatment decision for non-melanoma skin cancer (NMSC) in elderly patients, especially patients over 80 years old with multiple comorbidities. As a minimally invasive technology, iodine-125 seeds interstitial brachytherapy (BT) has been applied to solid tumors of the whole body, because it can offer a better dose distribution, which considered to be an effective, simple and safe alternative for local treatment of cancer. We aimed to explore its safety and efficacy for age 80 or older patient with early primary high-risk NMSC. As a retrospective and monocentric report, we collected 80+ year-old patients with early primary high-risk non-melanoma skin cancer treated by personalized iodine-125 seeds interstitial brachytherapy (PISI-BT) between December 2003 and May 2020. Survival status, efficacy, adverse effects (AEs), cosmetic result, cost were recorded (data cut-off, November 20st 2021). Results Only 9 patients met the criteria, median age was 86 (81-90), 5 of 9 were Eastern Cooperative Oncology Group (ECOG) 1, and each of them suffered from at least one comorbidity. After a median follow-up of 29.3 months (3-99), only 2 patients alive, 6 patients showed complete response (CR), 3 showed partial response(PR), and stable disease(SD), progressive disease(PD) were 0, respectively. No recurrences, disease persistence and AEs were detected during the follow-up and the death causes was irrelevant to NMSC. The cosmetic result of Excellent and Good were 2 and 4, 3 cannot be evaluated. The cost (included in the scope of medical insurance reimbursement) was acceptable. Conclusions PISI-BT could be an alternative in 80+ year-old patients with early primary high-risk NMSC. There is no one-size-fits-all treatment decision for non-melanoma skin cancer (NMSC) in elderly patients, especially patients over 80 years old with multiple comorbidities. As a minimally invasive technology, iodine-125 seeds interstitial brachytherapy (BT) has been applied to solid tumors of the whole body, because it can offer a better dose distribution, which considered to be an effective, simple and safe alternative for local treatment of cancer. We aimed to explore its safety and efficacy for age 80 or older patient with early primary high-risk NMSC. As a retrospective and monocentric report, we collected 80+ year-old patients with early primary high-risk non-melanoma skin cancer treated by personalized iodine-125 seeds interstitial brachytherapy (PISI-BT) between December 2003 and May 2020. Survival status, efficacy, adverse effects (AEs), cosmetic result, cost were recorded (data cut-off, November 20st 2021). Only 9 patients met the criteria, median age was 86 (81-90), 5 of 9 were Eastern Cooperative Oncology Group (ECOG) 1, and each of them suffered from at least one comorbidity. After a median follow-up of 29.3 months (3-99), only 2 patients alive, 6 patients showed complete response (CR), 3 showed partial response(PR), and stable disease(SD), progressi","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
BrachytherapyPub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.174
Wiwatchai Sittiwong, Pittaya Dankulchai
{"title":"PO73","authors":"Wiwatchai Sittiwong, Pittaya Dankulchai","doi":"10.1016/j.brachy.2023.06.174","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.174","url":null,"abstract":"Purpose To identify a predictive factor associated with local recurrence in prostate cancer patients receiving HDR brachytherapy. Materials and Methods Localized, non-metastatic prostate cancer patients who were treated with brachytherapy with or without external beam radiation (EBRT) between January 2015 to December 2021 were retrospectively reviewed. HDR monotherapy was prescribed at 19 Gy to prostate while HDR brachytherapy was prescribed at 15 Gy to prostate after EBRT of 45-50 Gy to whole pelvis. Factors to identify a predictor of local recurrence included prostate volume, dominant intraprostatic lesion (DIL) volume, PSA density and DIL-concentrated PSA (DILcPSA). DILcPSA is defined as the PSA density within the area of DIL volume which can be calculated by PSA density multiplied by DIL volume. Baseline patient characteristics and tumor characteristics were reported. Univariate and multivariate analysis were performed to identify factors associated local recurrence by using Cox's regression analysis. Results 32 patients with the median follow up time of 59.2 months were included. The median age of patients was 70 years. Most patients were categorized as unfavorable to very high risk (19 patients, 59.4%); however, most common grade group was grade group 2 (14 patients, 43.7%). Most patients received androgen deprivation therapy (ADT) either by medication or surgical castration (25 patients, 78.1%). The proportion of patients underwent HDR brachytherapy as monotherapy (18 patients, 56.2%) was similar to as a boost (14 patients, 43.8%). For tumor characteristics, most of DILs were located at peripheral zone (28 patients, 87.5%). Median DIL volume and prostate volume were 1.13 ml (95%CI 0.78 to 1.48), and 39.4 ml (95%CI 31.38 to 47.42), respectively. Median PSA density and DILcPSA were 0.30 (95%CI 0.12 to 0.48) and 0.33 (95%CI 0.15 to 0.51), respectively. There were 9 patients developed local recurrence. The rate of 5-year local recurrence-free survival was 68.5%. Among factors selected to predict local recurrence, DILcPSA was found to be significantly associated with local recurrence for both univariate and multivariate Cox's regression analysis with HR of 2.10 (95%CI 1.12 to 27.67) p=0.035 and 2.06 (95%CI 1.09 to 27.41) p 0.039, respectively. Prostate volume, DIL volume and PSA density were found no significant correlation with local recurrence. Conclusions DILcPSA could be a potential predictive factor to predict local recurrence in prostate cancer patients receiving HDR brachytherapy. To identify a predictive factor associated with local recurrence in prostate cancer patients receiving HDR brachytherapy. Localized, non-metastatic prostate cancer patients who were treated with brachytherapy with or without external beam radiation (EBRT) between January 2015 to December 2021 were retrospectively reviewed. HDR monotherapy was prescribed at 19 Gy to prostate while HDR brachytherapy was prescribed at 15 Gy to prostate after EBRT of 45-50 Gy to wh","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"25 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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