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Background: To determine outcomes of MRI-assisted radiosurgery (MARS) for salvage brachytherapy using the radioisotope 103 Pd after various upfront treatments including surgery, external beam radiotherapy, and brachytherapy., Methods: We retrospectively reviewed data for patients who underwent salvage MARS for intraprostatic lesions or prostate bed recurrences from 2016 to 2022. Biochemical recurrence, prostate cancer-specific, and overall survival, and the cumulative incidences of toxicities, were determined by Kaplan-Meier estimates. Cox proportional hazards models were used to determine associations between clinical and treatment variables and risk of toxicity., Results: Study included 31 patients with local recurrence after initial definitive treatment. Four (13%) were initially treated with prostatectomy and salvage radiation, twenty-four (77%) with external beam radiation, and three with brachytherapy. Most had intermediate- or high-risk prostate cancer at the time of diagnosis. Twenty-two patients (71%) had focal-gland and nine (29%) had whole-gland MARS LDR salvage brachytherapy. Median follow-up was 35-28 months. By last follow-up, 5 patients (16%) experienced recurrence and started ADT, 3 patients started ADT before experiencing recurrence due to physician discretion, and 23 patients (74%) remained without recurrence. No patients died of prostate cancer. Median PSA nadir for recurrence-free patients was 0.2 ng/mL (range, 0-0.9 ng/mL). Grade 3 toxicities occurred in 4 patients (13%) including 3 patients (13%) with genitourinary events only and 1 patient (3%) with both a grade 3 genitourinary and a grade 3 gastrointestinal event., Conclusions: In this modern series of patients undergoing salvage MARS with 103 Pd, we observed acceptable toxicity and early, promising biochemical disease control. These findings highlight the broader applicability of salvage MARS regardless of upfront treatment modality., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate treatment outcomes and toxicity in patients with stage T1-3N0M0 oral cancer treated with surgery followed by high-dose-rate brachytherapy (HDR-BT)., Methods and Materials: Retrospective study of 50 patients with stage T1-T3N0 tongue and floor-of-mouth cancer who underwent tumour excision (+ elective neck dissection) followed by postoperative HDR-BT due to the presence of negative prognostic factors (close or positive resection margins, lymphovascular and/or perineural invasion, deep invasion). The plastic tube technique (dose: 18 x 3 Gy b.i.d.) was used. Survival outcomes, toxicity, and prognostic factors were evaluated., Results: At a median follow-up of 81 months (range, 4-121), actuarial 5-year local control (LC), nodal control (NC) and progression-free survival (PFS) rates were 79%, 69%, and 64%. After salvage treatment (surgery + external beam radiotherapy), LC, NC, and PFS increased to 87%, 77%, and 72.3%, respectively. Five-year overall survival and cancer-specific survival (CSS) rates were 73% and 77%. Treatmentrelated toxicity included two cases of mandibular osteoradionecrosis and five cases of small soft tissue necrosis. T stage was significantly correlated with nodal control (p=0.02) and CSS (p=0.04). Tumour grade correlated with DFS (p=0.01)., Conclusion: Postoperative HDR-BT 18 x 3 Gy b.i.d. seems to be an effective method in patients with T1-3N0M0 oral cancer with negative prognostic factors after tumour resection., Competing Interests: Declaration of competing interest The authors declare no conflict of interest, (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: To present long-term toxicity and effectiveness outcomes of three prostate high-dose-rate (HDR) brachytherapy schedules: 38 Gy in 4 fractions, 24 Gy in 2 fractions, and 27 Gy in 2 fractions for men with low- or intermediate-risk prostate cancer., Methods and Materials: Patients treated with HDR brachytherapy monotherapy for prostate cancer were identified in a prospectively maintained, single institution database. Patients with AJCC T-stage ≤ T2b, Gleason score ≤ 7, prostate-specific antigen level ≤ 20 ng/mL, and ≥2 years of follow-up were included., Results: 671 patients were evaluated. 310 patients received 38 Gy in 4 fractions, 129 received 24 Gy in 2 fractions, and 232 received 27 Gy in 2 fractions. Median follow-up was 12.8 years, 10.6 years, and 8.1 years (p < 0.001), respectively. 231 (74.5%), 92 (71.3%), and 81 (34.9%) patients (p < 0.001) had low-risk disease. Rates of acute grade ≥2 GU toxicity were 11.1%, 12.3%, and 25.0% (p = 0.004), while chronic grade ≥2 GU toxicity were 17.0%, 22.6%, and 26.5% (p = 0.06). For low-risk patients, 10-year overall survival (OS), freedom from biochemical failure (ffBF), local control (LC), and freedom from distant metastasis (ffDM) were 86.6%, 93.3%, 97.9%, and 99.3%. For intermediate-risk patients, 10-year OS, ffBF, LC, and ffDM were 89.5%, 82.6%, 90.5%, and 97.4%. Higher PSA, higher Gleason score, perineural invasion, and 24 Gy or 27 Gy treatment schedules were predictors of biochemical failure., Conclusions: HDR brachytherapy monotherapy with 38 Gy in 4 fractions was associated with improved long-term ffBF compared with 24 Gy/27 Gy in 2 fractions, without any associated increase in GI or GU toxicity rates., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Background: Poor needle placement in prostate high-dose-rate brachytherapy (HDR-BT) results in sub-optimal dosimetry and mentally predicting these effects during HDR-BT is difficult, creating a barrier to widespread availability of high-quality prostate HDR-BT., Purpose: To provide earlier feedback on needle implantation quality, we trained machine learning models to predict 2D dosimetry for prostate HDR-BT on axial TRUS images., Methods and Materials: Clinical treatment plans from 248 prostate HDR-BT patients were retrospectively collected and randomly split 80/20 for training/testing. Fifteen U-Net models were implemented to predict the 90%, 100%, 120%, 150%, and 200% isodose levels in the prostate base, midgland, and apex. Predicted isodose lines were compared to delivered dose using Dice similarity coefficient (DSC), precision, recall, average symmetric surface distance, area percent difference, and 95th percentile Hausdorff distance. To benchmark performance, 10 cases were retrospectively replanned and compared against the clinical plans using the same metrics., Results: Models predicting 90% and 100% isodose lines at midgland performed best, with median DSC of 0.97 and 0.96, respectively. Performance declined as isodose level increased, with median DSC of 0.90, 0.79, and 0.65 in the 120%, 150%, and 200% models. In the base, median DSC was 0.94 for 90% and decreased to 0.64 for 200%. In the apex, median DSC was 0.93 for 90% and decreased to 0.63 for 200%. Median prediction time was 25 ms., Conclusion: U-Net models accurately predicted HDR-BT isodose lines on 2D TRUS images sufficiently quickly for real-time use. Incorporating auto-segmentation algorithms will allow intra-operative feedback on needle implantation quality., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Introduction: There is some evidence of a dose-response relationship for intravascular brachytherapy (IVBT) of native vessel or first-time in-stent restenosis (ISR). It has also been shown that in-field failure predominates following intravascular brachytherapy-treated lesions. Accordingly, it may be advantageous to increase the radiation dose(s) currently used. Given the rationale for escalation from currently doses, a scrutiny of the potential complications that have been reported seems timely., Methods: PubMed was searched from 1966 through November 21st, 2023, using the terms coronary and brachytherapy, yielding 1287 references. A 10/16/24 follow-up search of Embase, using the terms "coronary and brachytherapy and complications", yielding 511 articles. In total, 68 articles were identified as adverse event reports based on their title, or by scrutinizing articles that did not mention adverse events in their titles., Results: The best documented adverse IVBT-related event is the occurrence of late (> 1 month) thrombosis. Following identification of the risk, longer DAPT regimens were adopted, bringing the incidence to non-IVBT levels. A variety of other adverse events have been reported, including aneurysms, dissections, arterial spasm, "black holes" and vasomotor response inhibition. However, none of which were associated with adverse clinical outcomes., Conclusions: Nearly all reports regarding IVBT-related complications are retrospective analyses of a limited number of events, subject to reporting bias. Clinically important IVBT-related complications, at current doses, appear highly unlikely., (Copyright © 2024 American Brachytherapy Society. All rights reserved.)

Purpose: To evaluate outcomes of cervical cancer patients treated with abbreviated high dose rate brachytherapy (HDR-BT) that used 2-implants and delivered 4-5 fractions over 7-12 days rather than 21-28 days., Materials and Methods: Patients with stage IB2-IVA cervical cancer, treated with external beam radiation (EBRT) ± chemotherapy followed by abbreviated MR/CT-based HDR-BT were included. The planning aim was to achieve > 70Gy equivalent doses in 2Gy (EQD2 10Gy ) at Point A dose in patients undergoing intracavitary BT (ICBT) and > 85Gy EQD2 10Gy to the HRCTV in intracavitary-interstitial BT (IC-ISBT). The dose constraints to 2 cc of bladder, rectum and sigmoid were restricted to < 90Gy 3 , < 75Gy 3 and < 75Gy EQD2 3Gy respectively., Results: From 2020 to 2022, 245 patients were treated with EBRT followed by MR/CT-based HDR-BT. Median OTT was 57 days. The median HRCTV volume was 35.5cc with higher HRCTV in MR than CT-based (42.3cc vs. 32.8cc). The median dose to Point-A, HRCTV-D90, B2cc, R2cc and S2cc for ICBT was 78.1, 86.2, 87, 70.2 and 70.4Gy respectively. For IC-ISBT cohort, the median dose to HRCTV-D90, B2cc, R2cc, and S2cc was 86.1, 88.6, 70 & 66.7Gy respectively. The 3-years local control, pelvic control, locoregional, disease free and overall survival was 90%, 88%, 83.7%, 75.5% and 85% respectively. Late ≥ grade III gastrointestinal and genitourinary toxicities were 7.3% and 1.6% respectively with marginally higher toxicity in CT based cohort., Conclusion: Accelerated HDR-BT schedule of 2-implants 4-5 fractions is radiobiological iso-effective and clinically safe with comparable oncological outcomes and adverse events., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Background: An update of the 2007 and 2014 surveys of the American Brachytherapy Society (ABS) will elucidate current practice patterns of cervical cancer brachytherapy., Methods: A 40-question survey was sent to all ABS members in June-July 2023 and February 2024; 167 responses were received, with 140 used for analysis. Results were compared to the 2014 survey using chi-squared testing. Multivariable logistic regression was used to calculate adjusted odds ratios (aOR) with 95% confidence intervals (CI) for outcomes of interest., Results: Compared to 2014, MRI use for treatment planning of the first brachytherapy fraction increased from 34% to 63% (p < 0.001), prescription to the high-risk clinical target volume (HR-CTV) increased from 52% to 94% (p < 0.001), while Point A prescription decreased from 42% to 16% (p < 0.001). Additionally, procedural guidance with ultrasound significantly increased (79% vs. 32%, p < 0.001) along with the use of interstitial needles (always or nearly always, >80%) (29% vs. 4%, p < 0.001). MRI availability around the time of procedure was the largest challenge to incorporating MRI into brachytherapy treatment planning. Compared to those with MRI access reserved specifically for Radiation Oncology, respondents with shared-access or out-of-department MRI were less likely to obtain treatment planning MRIs for each brachytherapy fraction (22% vs. 75%; aOR 0.10 [95% CI, 0.03-0.30], p < 0.001)., Conclusion: For cervix cancer brachytherapy there has been significant increase in the use of MRI-based volumetric brachytherapy treatment planning, ultrasound guidance during procedures and the addition of interstitial needles. These advancements in practice patterns are congruent with published consensus guidelines and ongoing training initiatives. However, MRI access and lack of easy availability continue to be significant challenges for optimizing cervix brachytherapy., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: To investigate the occurrence of errors in transrectal ultrasound (TRUS)-based implant reconstructions for high-dose-rate brachytherapy (HDR-BT) in prostate cancer using an afterloader-integrated electromagnetic tracking (EMT) system., Materials and Methods: Fourteen patients were treated with one TRUS-based treatment fraction in an intraoperative setting while under general anesthesia, as part of their prostate HDR-BT (2×13.5 Gy) treatment. EMT measurements were performed before the start of the treatment in all implanted needles at dwell positions (DPs) with an interval of 5 mm. The Euclidean distances (EDs) between clinically reconstructed and EMT-measured DPs after registration were calculated. Errors were evaluated per needle (minimum ED of 2mm) and stratified into 4 severity levels (minor, moderate, major and severe). Error causes were investigated through retrospective inspection of TRUS imaging., Results: The median (range) ED between EMT-measured and clinically reconstructed DPs was 1.0 (0.1-9.4) mm. Higher EDs were observed in the anterior and lateral regions of the prostate. From 265 evaluated needle reconstructions, 23% (61/265) had minor errors or higher, while 9% (24/265) had major or severe errors. Severe errors were mostly caused by incorrect needle or depth selection. Major, moderate and minor errors were mostly caused by artifact, shadowing, and user errors, respectively., Conclusions: This study found that a quarter of needle reconstructions contained errors >2mm, and that high and severe errors were not uncommon. EMT can play an important role in detecting and preventing these reconstruction errors without disrupting the clinical workflow., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: Treating localized high-risk prostate cancer with a combination of external beam radiation therapy (EBRT) and high-dose-rate brachytherapy (HDR-BT) is a common approach. Moderately hypofractionated EBRT and a single HDR-BT boost simplifies the treatment. We aim to present our five-year results., Methods: In this study, 355 patients treated with moderately hypofractionated EBRT (42 Gy in 14 fractions) and a single HDR-BT boost (14.5 Gy) at Örebro University Hospital between 2008 and 2018 were included. They were followed with regular PSA tests., Results: The median age of the cohort was 70 years (range: 51-81) and the median follow-up duration was 56 months (range: 6-150). Among them, 45% were classified as very high-risk, 38% as high-risk and 17% as intermediate-risk. Adjuvant androgen deprivation therapy (ADT) with a median duration of 24 months was given to 75% of the patient cohort. The estimated 5-year failure free survival rates were 79% (whole cohort), 66% (very high-risk), 90% (high-risk) and 85% (intermediate-risk), respectively. Initial PSA > 10 ng/mL, Gleason score 9-10 and tumor stage T3 were significantly associated with biochemical failure (BF). A PSA bounce occurred in 53 (15%) cases and was inversely associated with BF (p = 0.001) for patients receiving ADT., Conclusions: Moderately hypofractionated EBRT and a single HDR-BT boost seems to be an effective treatment against intermediate- and high-risk localized prostate cancer. Treatment escalation strategies should be investigated for very high-risk patients where the risk of recurrence remains high., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine the long-term disease-free survival, long-term toxicity, and effect on health-related quality of life of a two-fraction regimen of high-dose-rate (HDR) prostate brachytherapy., Methods and Materials: Patients with low- or intermediate-risk prostate cancer were treated with CT-planned HDR brachytherapy as monotherapy in two implants of 13.5 Gy in one community cancer center. Prostate-specific antigen (PSA), International Prostate Symptom Score (IPSS) and Expanded Prostate Index Composite (EPIC) questionnaires were evaluated at each follow-up visit. Biochemical recurrence (Phoenix definition) was evaluated to determine disease-free survival at 5 and 7 years. Proportion of patients in each IPSS category (mild = 0-7, moderate = 8-18, severe = 19+) was evaluated at each follow-up interval., Results: Thirty patients were accrued to the study between 2014 and 2016. Median prostate-specific antigen was 8,7 (range 4.1-17.5). T stages were T1c = 65%, T2a = 21%, and T2b = 14%. Twenty-seven percent of patients had a Gleason score of 6 and 73% had a Gleason score of 7. 13% were in low risk category and 87% in intermediate risk category. Median follow-up was 84 months. There were no deaths at 84 months after brachytherapy. Disease-free survival was 90% at 5 years and 86% at 7 years. Two patients experienced late Grade 3 GU toxicity (6.6%)., Conclusions: This study serves as proof of concept that HDR monotherapy can be performed successfully with excellent long-term outcomes in a community cancer center with adequate training and experience. The long-term disease-free survival rate and the health-related quality of life seem acceptable as compared to other treatment modalities. Further study is ongoing with regard to the optimal dosing regimen for HDR monotherapy., (Crown Copyright © 2024. Published by Elsevier Inc. All rights reserved.)

Purpose: Before this study, no institution in China had undertaken the calculation and official establishment of reference values for the reference air kerma rate associated with high-dose rate 192 Ir sources used in brachytherapy. This research, carried out at the National Institute of Metrology (NIM) in China, has successfully established an 192 Ir reference radiation facility. Consequently, it has achieved the absolute measurement of the reference air kerma rate for high-dose rate brachytherapy using 192 Ir sources., Methods and Materials: For this study, a medical afterloader machine was acquired. The radiation source employed was a high-dose rate 192 Ir source for brachytherapy, produced by HTA Co., Ltd. A reference graphite cavity ionization chamber with a volume of 100 cm 3 was designed to serve as the ionization chamber for absolute measurements. The determination of various correction factors and physical constants was achieved through a method that combines Monte Carlo simulations with experimental techniques., Results: The study successfully accomplished the absolute measurement of the reference air kerma rate for the high-dose rate brachytherapy 192 Ir radiation source. The expanded uncertainty of the measurement results was 0.72% (k = 2). The relative standard deviation for the RAKR of the same 192 Ir radiation source was 0.073%., Conclusions: This study marks a significant advancement in the field of radiation therapy in China, particularly in the accurate dosimetry for brachytherapy using high-dose rate 192 Ir sources. The study will contribute to the BIPM.RI(I)-K8 international comparison, organized by the Bureau International des Poids et Mesures (BIPM), thus facilitating the international recognition of the measurement values., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Suture preplacement by the ocular oncology surgeon is a critical step before inserting a radioactive plaque for ocular melanoma brachytherapy. We report on a novel 3D-printing method to create a custom "dummy" plaque applicator for the 22 mm notched gold plaque using in-house 3D-printing., Methods: A computer-aided design (CAD) file was created replicating a heavily used gold plaque that no longer has a satisfactory "dummy" plaque. The file was exported as a 3D file (surface tessellation language, STL) and prepared using Formlabs' PreForm print software. The 3D-printed dummies were oriented on the printer to have no cups or supports on the surfaces that would come in contact with the patient's external sclera. The dummies were printed in FormLabs BioMed Clear V1 on a Formlabs Form-3 3D printer. Postprinting, the dummies were processed in isopropyl alcohol and cured according to manufacturer instructions. They were polished utilizing a rotary tool to improve transparency. Chemical and sterilization cycle tests were performed to ensure dummy integrity., Results: Four "dummy" plaques were printed. The 3D-printed "dummy" dimensions were verified to be within 0.5-mm of the notched plaque using digital calipers. The polishing process created acceptable light opacity for the eye plaque procedure in the operating room. No impactful discoloration or material change was observed during the chemical and sterilization cycle tests performed., Conclusions: 3D printing can produce custom eye plaque dummies using transparent, biocompatible, chemically inert materials suitable for human use. This capability introduces an additional layer of patient-specific hygienics., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Women on chronic anticoagulation (AC) who require operative brachytherapy for gynecologic malignancies represent a clinical challenge, but no guidelines exist regarding patient selection for brachytherapy or their perioperative management. We aimed to understand the incidence of hemorrhagic and embolic events in our patients on chronic AC and suggest management strategies for this patient population., Materials and Methods: A retrospective, single institutional study of patients treated with operative, gynecologic brachytherapy from 2013 to 2023 was performed to identify patients on chronic AC. We determined indications for AC use, oncologic therapy characteristics, duration of AC interruption, and therapy outcomes. The primary aim was to determine perioperative embolic or hemorrhagic complications as measured by the Common Terminology Criteria for Adverse Events., Results: Of 304 patients treated with operative implants, 32 (10%) were on chronic AC for venous thromboembolism (n = 25), or atrial fibrillation/flutter (n = 13). The most common malignancies were cervical (n = 15) and inoperable uterine (n = 11). Implants were intracavitary (n = 14), interstitial (n = 6), or hybrid (n = 12) with a median (range) of 2 (1-3) implants, 4 (2-5) fractions, and 2 (1-3) days of bedrest per implant. 63% (n = 20) had an epidural for analgesia. AC was held for a median 3 days in 94% (n = 30) prior to the operative implant, and pharmacologic DVT prophylaxis was used in 78% (n = 25). There were two grade ≥ 2 hemorrhagic events and no new embolic events., Conclusions: The rate of bleeding and embolic events was acceptable, and women on chronic AC should not be excluded from potentially lifesaving operative brachytherapy, including complex cases that require spinal analgesia and interstitial applicators., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Brachytherapy (BT) is a time and resource intensive treatment modality. Constraints to efficiency and throughput include resource, staff and physician availability. Herein, we introduce a daily BT procedure scorecard, designed to ensure adequate resource allocation based on the type of procedure(s) being performed., Methods: Data on BT procedures, number of fractions, number of patients, and the average daily caseload from 2021 to 2024 in our clinic were collected. Each BT procedure was assigned a score from 1 to 3 based on complexity and labor intensity, with 1 representing the least and 3 the most complex procedures. This data was then used to evaluate the efficiency of the BT scoring system., Results: Implementing the BT scorecard improved scheduling efficiency without compromising patient throughput. Despite the growth in case complexity, we demonstrated that the scoring system effectively prevents understaffing in our clinics. The goal is to limit the daily BT score to 10 per day when creating the schedule, ensuring balanced resource allocation., Conclusion: The strategies presented can enhance scheduling by ensuring an equitable workload distribution based on the BT schedule. These approaches should be considered in all high-volume BT clinics to optimize patient scheduling and throughput. Additionally, the scoring system allows clinics to develop full-time equivalent (FTE) staffing models that account for patient volume and case types, ensuring optimal resource utilization., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Objective: This study aimed to assess if prostate-specific antigen (PSA) threshold and PSA bounce are associated with oncological control after low-dose-rate brachytherapy (LDR-BT) alone or with external beam radiotherapy (EBRT), with or without androgen deprivation therapy (ADT), considering serum testosterone levels., Methods: This study enrolled 944 prostate cancer patients treated at a single institution with LDR-BT alone or LDR-BT combined with EBRT, with or without ADT. The Fine-Gray hazard model was used to evaluate factors related to clinical failure, including experience of PSA bounce between baseline and 2, 4, or 7 years after LDR-BT and PSA value (0.1, 0.2, or 0.5 ng/mL) with normal testosterone levels at 2, 4, and 7 years after LDR-BT, respectively., Results: Patients with normal testosterone levels and a PSA of 0.2 or 0.5 ng/mL at 2, 4, and 7 years after LDR-BT had a significantly better clinical failure free rate (CFFR) than those with PSA levels >0.2 or >0.5 ng/mL or low testosterone levels. Multivariate analysis revealed that PSA <0.1, 0.2, or 0.5 ng/mL with normal testosterone levels at 2, 4, and 7 years and experience of PSA bounce between baseline and 2 or 4 years after LDR-BT were significantly related to better CFFR., Conclusions: Patients with normal serum testosterone levels who reached PSA of <0.1, 0.2, or 0.5 ng/mL after LDR-BT, or those who experienced PSA bounce, showed better oncological control., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: The lack of training is a significant barrier to practicing brachytherapy (BT). Tata Memorial Centre, alongside international BT experts and BrachyAcademy, developed a hybrid gynecological BT training module. This study outlines the preparation, organization, and execution of the 2022-2023 Mumbai training, evaluates its effectiveness, and highlights areas for improvement., Materials and Methods: Participants were radiation oncologists (RO) and medical physicists (MP) with experience in gynecological BT aiming to transition to image-guided brachytherapy (IGBT). The training covered cervical, endometrial, vaginal, vulvar, periurethral cancers, and pelvic reirradiation. The hybrid course included online pre and postcourse homework assignments, a live workshop with hands-on training, a 6-month online follow-up, and a 12-month opportunity to share the transition experience., Results: The December 2022 Mumbai live workshop spanned 2.5 days, attracting 39 participants from 8 countries (Asia, Africa, Australia/Oceania). Feedback rated the course 9/10, with 78% fully meeting expectations. Forty-four percent suggested extending hands-on training. At the 6-month follow-up, response rates were low (33% RO, 11% MP). Among responding RO, 70% reported practice changes after attending the course, 40% implemented IGBT concepts in clinical practice, and 50% increased confidence in image-guided procedures. Overall, 45% of respondent sites could strengthen their intracavitary/interstitial program, while others faced limitations due to lack of access to advanced BT applicators., Conclusion: The hybrid gynecological BT training concept was successfully executed. Areas for improvement include extending hands-on training and enhancing participant engagement postcourse. Structured steps beyond training may be needed to improve the utilization of advanced brachytherapy for gynecological cancers., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: A new mobile cone beam computed tomography (CBCT) imaging ring (IRm, Elekta, v2.10.6, Veenendaal, Netherlands) has recently been proposed for brachytherapy to improve procedure efficiency. We describe the commissioning process and end-to-end tests for GYN HDR brachytherapy employing IRm CBCT imaging., Materials and Methods: Commissioning included imaging isocenter test, 3D image quality, 2D imaging quality, image dose, and tube characteristics. CIRS HDR GYN phantom and Venezia CT/MR gynecological applicator were used to perform end-to-end (E2E) tests and optimize workflow. Venezia applicator and four interstitial needles were inserted into the phantom and IRm CBCT images were acquired. Phantom and applicator were scanned with CT scanner (Siemens SOMATOM go.Open Pro) using department's pelvis imaging protocol. MR imaging was performed using 0.35T MR Linac TRUFI pulse sequence. CBCT images were registered to CT and MR using rigid registration to assess image quality and applicator geometry fidelity., Results: All physics tests passed within acceptance tolerances. Registration of CBCT images to MR and CT scans was acceptable for applicator placement. Applicator registration of CBCT images to CT demonstrated excellent agreement of most distal source dwell position (<1 mm). Slice thickness was also measured to be 1.25 mm, within 0.5 mm of its nominal value., Conclusion: Based on E2E and commissioning results, IRm is an appropriate tool for brachytherapy treatment planning. This study demonstrated good image quality in GYN phantom and Venezia applicator using the IRm. Distal source dwell position agreement between CBCT and CT was acceptable for clinical use., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Objective: We utilized the National Cancer Database (NCDB) to evaluate trends and assess outcomes in radiation therapy (RT) boost modality and total dose among medically inoperable endometrial cancer (EC) patients with locoregional disease., Methods: Patients with International Federation of Gynecology and Obstetrics (FIGO) stage I - IIIC2 inoperable EC treated with RT ± chemotherapy were analyzed. Practice patterns compared external beam RT (EBRT) versus high-dose-rate brachytherapy (BT) boost and total RT dose (palliative: ≤3000 cGy, definitive low dose [DLD]: 4500 - 6249 cGy, definitive high dose [DHD]: ≥6250 cGy) over time. Kaplan-Meier method evaluated overall survival (OS) and Cox proportional hazard modeling assessed variables associated with OS., Results: NCDB included 1755 total cases, of which 1209 received a radiotherapy boost. From 2004 to 2019, boost modality rates differed with increasing utilization of BT consolidation and a decreasing rate of palliation. Predictors of a palliative dose were stage III disease, Black race, N2 disease, and poorly or undifferentiated grade. Multivariable analysis found BT boost was associated with lower mortality compared to EBRT (HR: 0.81, CI: 0.68-0.97; p = 0.019). Mortality rates were higher for palliation versus DHD. Additional factors associated with inferior survival were increasing age, worse Charlson-Deyo score, higher T stage, higher N stage, and moderately, poorly, or undifferentiated grade., Conclusions: Utilization of BT boost for locoregionally confined, medically inoperable EC has increased since 2004. Brachytherapy consolidation remains an effective RT modality for medically inoperable EC, associated with lower mortality compared to EBRT consolidation., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Surgically targeted radiation therapy (STaRT) with Cesium-131 seeds embedded in a collagen tile is a promising treatment for recurrent brain metastasis. In this study, the biological effective doses (BED) for normal and target tissues from STaRT plans were compared with those of external beam radiotherapy (EBRT) modalities., Methods: Nine patients (n = 9) with 12 resection cavities (RCs) who underwent STaRT (cumulative physical dose of 60 Gy to a depth of 5 mm from the RC edge) were replanned with CyberKnife Ⓡ (CK), Gamma Knife Ⓡ (GK), and intensity modulated proton therapy (IMPT) using an SRT approach (30 Gy in 5 fractions). Statistical significance comparing D95% and D90% in BED 10Gy (BED 10Gy 95% and BED 10Gy 90%) and to RC + 0 to + 5 mm expansion margins, and parameters associated with radiation necrosis risk (V8 3Gy , V10 3Gy , V12 3Gy and V24 3Gy ) to the normal brain were evaluated by a Wilcoxon-signed rank test., Results: For RC + 0 mm, median BED 10Gy 90% for STaRT (90.1 Gy 10 , range: 64.1-140.9 Gy 10 ) was significantly higher than CK (74.3 Gy 10 , range:59.3-80.4 Gy 10 , p = 0.04), GK (69.4 Gy 10 , range: 59.8-77.1 Gy 10 , p = 0.005), and IMPT (49.3 Gy 10 , range: 49.0-49.7 Gy 10 , p = 0.003), respectively. However, for the RC + 5 mm, the median BED 10Gy 90% for STaRT (34.1 Gy 10 , range: 22.2-59.7 Gy 10 ) was significantly lower than CK (44.3 Gy 10 , range: 37.8-52.4 Gy 10 ), and IMPT (46.6 Gy 10 , range: 45.1-48.5 Gy 10 ), respectively, but not significantly different from GK (34.1 Gy 10 , range: 22.8-47.0 Gy 10 ). The median V24 3Gy was significantly higher in CK (11.7 cc, range: 4.7-20.1 cc), GK(6.2 cc, range: 2.3-11.9 cc) and IMPT (19.9 cc, range: 11.1-36.6 cc) compared to STaRT (1.1 cc, range: 0.0-7.8 cc) (p < 0.01)., Conclusions: This comparative analysis suggests a STaRT approach may treat recurrent brain tumors effectively via delivery of higher radiation doses with equivalent or greater BED up to at least 3 mm from the RC edge as compared to EBRT approaches., Competing Interests: Disclosure Tugce Kutuk: None. Rupesh Kotecha: Honoraria from Accuray Inc., Elekta AB, ViewRay Inc., Novocure Inc., Elsevier Inc., Brainlab, Kazia Therapeutics, Castle Biosciences, and institutional research funding from Medtronic Inc., Blue Earth Diagnostics Ltd., Novocure, Inc., GT Medical Technologies, AstraZeneca, Exelixis, ViewRay, Inc., Brainlab, Cantex Pharmaceuticals, and Kazia Therapeutics. Roberto Herrera: None. DJay J Wieczorek: None. Zachary W. Fellows: None. Vibha Chaswal: None. Alonso La Rosa: None. Vivek Mishra: None. Michael W McDermott: Consultant Deinde Medical and Stryker Medical. Vitaly Siomin: None. Minesh P Mehta: Consulting fees from Karyopharm, Sapience, Zap, Mevion, Xoft, BOD Oncoceutics, Kazia Therapeutics; stock in Chimerix. Alonso N Gutierrez: Honoraria from ViewRay, Inc., Elekta AB, IBA AB. Ranjini Tolakanahalli: None., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Background and Purpose: Anemia is common in locally advanced cervical cancer. Clinical practice varies greatly for management of anemia during brachytherapy, with some centres providing red cell transfusion to increase hemoglobin levels above 100 g/L., Materials and Methods: This is a retrospective observational cohort study of adult patients with cervical cancer treated with brachytherapy at two academic hospitals. One hospital (H1) uses a liberal transfusion strategy with hemoglobin threshold of 100 g/L during brachytherapy and the other uses a restrictive target of 70 g/L (H2)., Results: Overall, 336 patients met inclusion criteria (H1: 150 patients, H2: 186 patients). 11 patients were excluded (2 at H1, 9 at H2). Demographics at both sites were comparable, except for cancer stage and smoking history. External beam radiation and chemotherapy provided was similar. Hemoglobin values were compared at baseline (within 4 weeks of oncology consult), and prior to the first and second brachytherapy treatments. In total, 101red blood cell (RBC) units were transfused to patients at H1 and 19 units to patients at H2. Patients were followed for a median of 37.0 months (0.6-80.5) at H1, and 33.3 months (1.6-82.0) at H2. There was no significant difference in progression-free or overall survival. Multivariable logistic regression analysis showed that FIGO stage was a predictor for both overall survival and cancer progression. Age, tumor size, chemotherapy, and hemoglobin levels were not predictors of disease progression or mortality., Conclusions: The practice of liberal transfusion should be re-evaluated in the absence of robust data to support its use., (Crown Copyright © 2024. Published by Elsevier Inc. All rights reserved.)

Objective: The prognosis of recurrent cervical cancer tends to be poor and there are limited effective treatments currently available for these patients. This study was developed to find a safe and effective treatment for patients with central pelvic recurrent cervical cancer., Materials and Methods: This retrospective study analyzed patients with central pelvic recurrent cervical cancer who received 3D-printed individual template (3D-PIT) brachytherapy between February 2019 and June 2023. Analyses of dosimetric parameters, toxicity-related complications, and survival were conducted based on the data of these patients., Results: Twenty-one patients with central pelvic recurrent cervical cancer patients were enrolled. All of them received 3D-printed individual template (3D-PIT) brachytherapy. The mean respective adjusted cumulative HRCTV-D90 and HRCTV-D98 values for these patients were 86.9 Gy and 75.4 Gy. And the local control (LC) rate of these patients was 57.1%. In these 21 patients, only 2 (9.5%) of them experienced grade 3-4 rectal adverse reactions, while 7 (33.3%) patients experienced grade 3-4 bladder adverse reactions. 5(23.8%) patients had fistula, while 3 of these 5 patients had undergone prior anti-VEGF targeted drug treatment which is a risk factor of fistula. The respective 2-year rates of overall and progression-free survival (OS and PFS) for these patients were 72.9% and 57.4%, with a 26-month median PFS., Conclusions: These single-institution data highlight the potential viability of 3D-PIT brachytherapy as an approach to managing intractable central pelvic recurrent cervical cancer following first-line treatment., (Copyright © 2024. Published by Elsevier Inc.)

Purpose: Ablative therapies for primary and secondary liver malignancies are increasingly adopted in current guidelines. Nevertheless, surgical resection remains the gold standard in most curative therapy settings. Extensive studies on mortality and morbidity after ablative treatment of the liver are missing. We investigated complications and mortality after ablative treatment in a large, unselected study cohort., Materials and Methods: Standardized patient and treatment data in 4374 percutaneous and angiographic ablative procedures of the liver from the DRG-based hospital reimbursement system (diagnosis-related groups) of an academic hospital in Germany were retrospectively evaluated. We analyzed descriptive patient data, length of stay (LOS), pre-existing medical conditions, previous gastrointestinal surgeries, severe complications, and occurrence of death., Results: Treatment of secondary liver malignancies constituted over two-thirds of all procedures (71%, n = 3053). The mean LOS was 4.1 ± 3.5 days. Severe complications were documented in 1.4% and in-house death in 0.2% of cases, significantly more often after treatment with chemoembolization of primary liver malignancies (p = 0.003; p = 0.0001). Previous partial liver resection, partial bowel resection, and chronic renal failure were independent risk factors for the occurrence of severe complications., Conclusion: Severe complications and in-hospital death are rare in the treatment of primary and secondary liver malignancies with percutaneous and angiographic procedures. They are a viable alternative or addition to a surgical approach in treating liver lesions., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: This study was conducted to compare the differences between 3D-printed multichannel non-co-planar vaginal applicators and single-channel vaginal applicators in cervical cancer patients with positive or close surgical margins., Methods: Between January 2015 and June 2023, 104 cervical cancer patients who underwent radical surgery with positive or close surgical margins were enrolled to receive concurrent intensity-modulated chemoradiotherapy combined with 3D-printed multichannel non-co-planar vaginal applicators (3D-printed group, 41 patients) or single-channel vaginal applicators (single-channel group, 63 patients) guided brachytherapy. The dosimetric parameters, 5-year local control (LC), progression-free survival (PFS), overall survival (OS) of two groups were retrospectively analyzed., Results: The high-risk clinical target volume (D90, D100) and high-dose volume fraction (V150) in 3D-printed group were significantly higher than those in single-channel group (p < 0.05), and the homogeneity index (HI) and conformal index (COIN) were equally better in 3D-printed group. In 3D-printed group, the D2cc, D1cc, and D0.1cc of the bladder and rectum were significantly lower than those of the single-channel group (p < 0.05). The 3D-printed group had significantly superior 5-year LC (70.0% vs. 51.3%, p = 0.041) and PFS (63.0% vs. 44.2%, p = 0.045), but OS were not significantly different between treatment groups (75.4% vs. 59.7%, p = 0.112). The incidence of radiation enteritis and cystitis was lower in the 3D-printed group than in the single-channel group, but no statistical difference was noted., Conclusions: The 3D-printed multichannel non-co-planar vaginal insertion applicators show the advantage of target dose, improve the LC and PFS in patients with positive or close surgical margins after cervical cancer surgery. Thus, the popularization of this method and its application may be of value., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: Brachytherapy is associated with improved overall survival in cervical cancer patients, but the utilization seems hindered by high costs and relatively low reimbursement, particularly in the US. A one-room brachytherapy suite with CT (ORBT) could optimize the treatment workflow. By eliminating transport and waiting times, limiting applicator movement, and providing real-time applicator placement feedback, treatment time and costs could potentially be reduced. This study assesses the potential value of implementing ORBT in cervical cancer treatment., Methods and Materials: A variable cost model was developed to compare current (multi-room) brachytherapy workflows (MBRT) to ORBT, taking into account staff utilization, staff, equipment and consumables costs and room expenses. Two current care scenarios were simulated; applicator placement performed in the operating room (S1), and applicator placement performed in a brachytherapy suite (S2). For both scenarios literature reported fraction times of MBRT were compared to a range of ORBT times. Sensitivity analyses were performed to determine the influence of input parameters., Results: In scenario one, the results showed yearly savings of $45,572 up to $339,439 (USD), assuming a 5% and 20% reduction in fraction duration, respectively, in ORBT compared to MRBT. In scenario two, ORBT does not result in costs savings at 5% to 15% improvement. Therefore, only when ORBT results in a >20% improvement of fraction time, cost will be saved., Conclusions: The results indicate that reducing procedure time (using ORBT) can lead to cost savings, depending on the current workflow. Savings seem to depend mostly on applicator placement location, number of patients per year, and involved personnel., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: High-dose-rate brachytherapy (HDR-BT) is now becoming more common than low-dose-rate and pulsed-dose-rate BT in the treatment of lip cancer. However, due to the limited history of HDR-BT, relatively few studies have been published. Two institutions (in Ukraine and the USA) reviewed their clinical outcomes of lip cancer patients treated with HDR-BT as monotherapy or in combination with external beam radiotherapy (EBRT)., Methods and Materials: An interstitial (IS), surface custom mold (SC), or a combination of IS and SC (IS+SC) was used for treatments based on the depth of tumor invasion. Prescription doses were 24 Gy in 6 BID fractions when combined with 46-50 Gy of EBRT, 45-55 Gy in 9-10 BID fractions for IS and IS+SC monotherapy or 3 Gy × 16 daily fractions for SC monotherapy., Results: A total of 33 cases of lip cancer were treated from 2015 to 2021. By using TNM staging classification, there were 14 stage I (42.4%), 15 stage II (45.5%), and 4 stage III (12.1%) lip cancers. Thirty-one patients (93.9%) had a complete response to the treatment. Only 2 patients (6.1%) displayed local recurrence. Grade 1, 2, and 3 acute toxicities were observed in 30.3%, 51.5%, and 18.2% of patients, respectively. Grade 1, 2, and 3 late toxicities were observed in 39.4%, 21.2%, and 0.0% of cases. Cosmetic results were excellent in 21.2%, good in 54.5%, fair in 18.2%, and poor in 6.1% of patients., Conclusions: HDR-BT is an effective and safe treatment for lip carcinomas with excellent local control, functional, and cosmetic outcomes and should be considered as a standard treatment., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Introduction: Interstitial brachytherapy (ISBT) is a known treatment for vaginal recurrence of endometrial cancer. This study reviews a large tertiary institution's ISBT experience and outcomes for vaginal recurrences., Material and Methods: Patients who underwent salvage ISBT for vaginal recurrence of endometrial cancer from January 1, 2014 to August 31, 2021, were identified. Initial and salvage disease factors and treatments were recorded. Outcomes were calculated including overall survival, local, and distant failure., Results: Thirty-nine patients were included; thirty received external beam radiotherapy and interstitial brachytherapy (EBRT + ISBT) while 9 received ISBT alone. At initial diagnosis, the ISBT alone group had an older median age, with stage IA-IV disease, frequently receiving adjuvant treatment, compared to the EBRT with ISBT group with mainly stage IA disease who did not. Median follow up was 22 months and median time to recurrence 14 months (16.5 months in EBRT + ISBT group and 14 in the ISBT alone group). Two-year overall survival was 85% for all patients, 85.6% and 83.3%in the EBRT + ISBT and ISBT alone groups, respectively. Local failure was 22.7% for all patients, 16.7% in the EBRT + ISBT group and 11.1% in the ISBT alone group. Median HRCTV D90 (EQD2) was 76.8 Gy in the EBRT + ISBT group, and 57.9 Gy in the ISBT alone group. Late grade 3 or higher toxicity occurred in only 3 patients., Conclusions: EBRT + ISBT is an effective treatment for endometrial cancer vaginal recurrence, with acceptable toxicity. ISBT alone is an option for patients with contraindications to or with previous treatment of pelvic radiation., (Copyright © 2024. Published by Elsevier Inc.)

Background: Radical urethectomy ± cystectomy has long represented the standard of care for rare primary urethral cancer (PUC). With our analysis, we want to demonstrate the efficacy and safety of brachytherapy (BT) of urethra for organ preservation., Materials and Methods: We analyzed treatment procedures and results of 3 patients with PUC, which have been treated in our department between 2011 and 2020 with brachytherapy. One male patient underwent brachytherapy with chemoradiotherapy after transurethral resection (TUR). Brachytherapy has been performed as high-dose-rate (HDR) boost with a cumulative dose of 8 Gy (9.3 Gy EQD2-α/β = 10 Gy ). The 2 further female patients have been treated with sole pulsed-dose-rate (PDR) brachytherapy with a total dose of 49.9 Gy (50.3 Gy EQD2-α/β = 10 Gy ) and 62.2 Gy (64.6 Gy EQD2-α/β = 10 Gy )., Results: Median follow-up was 103 months (41-153). No local recurrence occurred and all patients are still alive. For the male patient we documented Grade 3 cystitis. As late side effects the pre-existing Grade 2 incontinence worsened to Grade 3. Among female patients one developed Grade 3 vaginal synechiae. There was no Grade ≥4 toxicity., Conclusion: Brachytherapy in PUC is a feasible and promising option with high local control rate and tolerable toxicity. It provides a good alternative to surgery for organ preservation in selected patients., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: To quantify changes in prostate size and seed movement over time after transperineal implantation of stranded 125 I seeds, and to determine their impact on prostate dosimetry., Methods: CT and MR (T2, balanced steady-state free precession) image triplets were acquired on days 0, 3, 10, and 30 for a cohort of 20 patients and registered automatically. Prostate contours were drawn on MR-T2 images; seeds were found and matched in successive CT images. Prostate volume and dimensions, seed movements, and prostate dose metrics V200, V150, V100 and D90 were calculated, and their dynamic behaviors quantified in an operationally defined prostate coordinate system., Results: Cohort-averaged reductions in prostate A-P dimension (∼8%) and L-R dimension (∼5%) inferred from seed movements agreed with those obtained from contour measurements, whereas prostate volume and S-I dimension (implant direction) reductions inferred from seed movements were overestimated by about 30%. Average overall seed movement was 4.8 ± 3.0 mm, of which the only identifiable systematic component was resolution of prostate edema. Cohort-averaged ratios of prostate V200, V150, V100, and D90 on day 30 relative to day 0 were 1.67, 1.33, 1.02, and 1.08, respectively., Conclusions: Postimplant prostate size reduction in the SI (implant) direction cannot reliably be inferred from stranded seed movements. Apart from large-scale migration, residual seed movements relative to the prostate after accounting for edema resolution appear to be random. Prostate V100 and D90 changes 30 days post implant are modest, whereas those for V150 and V200 are substantial., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: We aim to investigate perioperative and subacute postoperative complications in patients undergoing LDR or HDR monotherapy for prostate cancer. We hypothesize a low rate of complications, and a favorable toxicity profile in patients treated with HDR compared to LDR., Materials and Methods: A prospectively collected institutional database was queried for patients treated with HDR or LDR prostate monotherapy between 1998 and 2021. Toxicities were determined per CTCAE. Claims based billing codes were obtained to identify additional events. Events occurring within 4 months of treatment were defined as perioperative or subacute postoperative complications., Results: 759 patients were identified, 446 received LDR with 125 I, and 313 received HDR with 192 Ir. HDR patients had higher risk features: 75.7% with Gleason score 7+ versus 2.4% of LDR, and 16% with initial PSA 10+ ng/mL versus 2.7% of LDR. Toxicities were mild with the most common being grade 1 GU frequency and nocturia at ∼50%. HDR patients had significantly less grade 2 dysuria (2.6% vs. 9.0%), frequency (4.8% vs. 9.4%), hematuria (1.0% vs. 5.2%), nocturia (3.8% vs. 9.4%), and urinary obstructive symptoms (7.3% vs. 11.2%), all statistically significant. 11 (1.4%) patients had infection requiring antibiotics: 8 (1.8%) from the LDR group and 3 (1%) from the HDR group. Cardiopulmonary events were low at <2% overall, without difference between HDR and LDR., Conclusions: Overall toxicity rates support the safety of prostate brachytherapy. HDR monotherapy is associated with significantly less perioperative and subacute postoperative GU events when compared to LDR monotherapy. Cardiopulmonary events were equally rare in both groups., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: This study compares conventional 192 Ir-based high dose rate brachytherapy (HDR-BT) with 169 Yb-based HDR intensity modulated brachytherapy (IMBT) for focal prostate cancer treatment. Additionally, the study explores the potential to generate less invasive treatment plans with IMBT by reducing the number of catheters needed to achieve acceptable outcomes., Methods and Materials: A retrospective dosimetric study of ten prostate cancer patients initially treated with conventional 192 Ir-based HDR-BT and 5-14 catheters was employed. RapidBrachyMCTPS, a Monte Carlo-based treatment planning system was used to calculate and optimize dose distributions. For 169 Yb-based HDR IMBT, a custom 169 Yb source combined with 0.8 mm thick platinum shields placed inside 6F catheters was used. Furthermore, dose distributions were investigated when iteratively removing catheters for less invasive treatments., Results: With IMBT, the urethra D 10 and D 0.1cc decreased on average by 15.89 and 15.65 percentage points (pp) and the rectum V 75 and D 2cc by 1.53 and 11.54 pp, respectively, compared to the conventional clinical plans. Similar trends were observed when the number of catheters decreased. On average, there was an observed increase in PTV V 150 from 2.84 pp with IMBT when utilizing all catheters to 8.83 pp when four catheters were removed. PTV V 200 increased from 0.42 to 2.96 pp on average. Hotspots in the body were however lower with IMBT compared to conventional clinical plans., Conclusions: 169 Yb-based HDR IMBT for focal treatment of prostate cancer has the potential to successfully deliver clinically acceptable, less invasive treatment with reduced dose to organs at risk., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: This study aimed to evaluate the effectiveness and safety of iodine-125 brachytherapy as a treatment for right lower paratracheal lymph node metastasis following unsuccessful prior therapies., Methods: A retrospective review of patients who underwent iodine-125 brachytherapy for right lower paratracheal lymph node metastasis was conducted. The study included 24 patients who met the predefined criteria. Iodine-125 seeds were implanted under CT guidance, and treatment planning was performed using a treatment planning system. The primary endpoint was the objective response rate (ORR), while overall survival (OS) and complications were secondary endpoints., Results: The ORR was 87.5%, with 4 patients achieving complete response (CR) and 17 patients achieving partial response (PR). The mean diameter of metastatic lymph nodes significantly reduced from 40.21 ± 6.66 mm before treatment to 12.25 ± 9.27 mm at the last follow-up (p < 0.001). The median OS was 14.70 months, with 1-year and 2-year survival rates of 78.9% and 20.9%, respectively. Clinical symptoms significantly improved, as indicated by increased Karnofsky Performance Score (KPS) scores. Complications were manageable, with no procedure-related deaths., Conclusion: Iodine-125 brachytherapy demonstrated promising efficacy and safety as an alternative treatment for right lower paratracheal lymph node metastasis after unsuccessful prior therapies., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: Eye plaque brachytherapy (EPBT) is the most common treatment for uveal melanoma with high local control rates of 95-100%. When local recurrences occur following EPBT, salvage options include enucleation, transpupillary thermotherapy (TTT), external beam radiation, or re-irradiation with EPBT. The purpose of this study is to report our institution's experience with EPBT re-irradiation for locally recurrent uveal melanoma., Methods and Materials: Patients were included if they were previously treated for uveal melanoma with EPBT, experienced local recurrence, and were subsequently treated at our institution with EPBT from 2016- 2020., Results: A total of 5 patients with median age 68 years were included. All patients were initially treated at an outside institution (OSI) with Iodine-125 or Ruthenium-106 EPBT. Mean time between EPBT at the OSI and EPBT at our facility was 130 months (range 28-231 months). Patients were re-irradiated with Iodine-125 EPBT prescribed to 85 Gy over 168 hours. Median follow up after re-treatment at our center was 24 months. Local control among this cohort was 100%. Metastasis occurred in two patients after re-treatment, at 8 months and 7 months. At last follow up, all treated lesions were decreased in size. Four patients experienced worsening visual acuity. Four patients developed cataracts, while two patients developed radiation retinopathy with cystoid macular edema requiring anti-VEGF injections. One patient developed radiation retinopathy but did not require injections. No patients required enucleation., Conclusions: Re-treatment of locally recurrent uveal melanomas with EPBT is a feasible alternative to enucleation with a high local control rate. Ocular toxicities have not been significant enough to require enucleation., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Whether brachytherapy based microboosting of the dominant intraprostatic lesion (DIL) improves outcomes over standard approaches is not known. The purpose of this study is to perform a systematic review on brachytherapy microboosting of the DIL to evaluate clinical outcomes and toxicities with this treatment approach., Materials and Methods: This review was performed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Databases including Pubmed, Embase, and Google Scholar were queried. About 16 studies met our inclusion criteria. These studies reported PSA control and/or toxicities based on standardized scales., Results: There were 10 studies (two monotherapy, eight combination) that used HDR microboosting on a total of 516 patients. HDR dose (EQD2 assuming alpha/beta of 1.5) to the DIL ranged from 90 to 180 Gy. Most patients were low/intermediate risk. PSA control rates at 5-8 years ranged from 69% to 100%. Acute/late G3-G4 GU/GI toxicities ranged from 0% to 12%. There were six studies (five monotherapy, one combination) that used LDR microboosting on a total of 1041 patients. Studies performed a microboost of 130-150% of the whole gland prescription to the DIL. Most patients were low/intermediate risk. PSA control rates at 5 years ranged from 69% to 98%. Acute/late G3-4 GU/GI toxicities ranged from 0% to 4%., Conclusions: Over 1000 patients have been treated with a brachytherapy based microboost in published series. Severe acute/late toxicities appear limited. PSA control rates with more than 5 years of follow-up are limited. Longer-term follow-up is needed to determine ideal utilization of this approach., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: To develop and validate risk models incorporating clinical and/or imaging parameters based on three-dimensional treatment-planning systems (3D-TPS) to predict the occurrence of 125 I seed migration and the number of migrated seeds <2/≥2 to the chest after brachytherapy for patients with malignant hepatic tumors., Methods and Materials: A total of 480 patients diagnosed with malignant liver tumors receiving 125 I seed brachytherapy from July 2010 to May 2020 were retrospectively enrolled. Variables included 3D-TPS-based CT parameters, that is, the distance from the seed to the inferior vena cava (DSI), the distance from the seed to the second hepatic portal (DSP) and the angle from the seed to the second hepatic portal (ASP), and patients' clinical characteristics, that is, the number of seed implantation procedures (NSP), the maximum number of implanted seeds one time (MAX) and laboratory parameters within 1 week before treatment. Two sets of logistic regression models incorporating clinical and/or imaging variables were developed to predict the occurrence of seed migration and the number of migrated seeds <2/≥2. Model performance was assessed by ROC analysis and decision curve analysis., Results: Compared with the clinical models, the combined model showed a higher discriminative ability for both the prediction of migration occurrence and number of migrated seeds ≥ 2/<2 to the chest (AUC, 0.879 vs. 0.668, p < 0.05; 0.895 vs. 0.701, p < 0.05). The decision curve analysis results indicated higher net benefits of combined models than clinical models. Variables, including DSI, NSP and pretreatment lymphocyte-to-neutrophil ratio, acted as the most important predictors in combined models., Conclusions: The proposed combined models based on 3D-TPS improved discriminative abilities for predicting 125 I seed migration and number of migrated seeds <2/≥2 to the chest after hepatic brachytherapy, being promising to aid clinical decision-making., (Copyright © 2024. Published by Elsevier Inc.)

Simulation is a technique used in healthcare to replicate clinical scenarios and improve patient safety, efficacy, and efficiency. Simulation-based medical education facilitates training and assessment in healthcare without increasing risk to patients, supported by ample evidence from surgical/procedural specialties. Simulation in radiation oncology has been leveraged to an extent, with successful examples of both screen-based and hands-on simulators that have improved confidence and performance in trainees. In the current era, evidence substantiates a significant deficit in brachytherapy procedure education, with radiation oncology residents reporting low confidence in this procedural skill, largely attributable to insufficient caseloads at some centers. Simulation-based medical education can facilitate structured training and competency-based assessment in brachytherapy skills. This review discusses existing advances and future directions in brachytherapy simulation, using examples from simulation in surgical specialties., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Introduction: Iodine-125 (I-125) seeds, commonly used in low-dose rate brachytherapy for ocular malignancies, are often discarded after a single use. This study examines the potential cost savings at an institution with high ocular melanoma referrals, by re-using I-125 seeds for eye-plaque brachytherapy., Methods: In this single-institutional retrospective analysis, data was collected from I-125 seed orders from 8/2019 through 10/2022. Information including number of seeds ordered per lot, number of plaques built per lot, and number of seeds used per lot were collected. Cost per lot of seed was assumed to be the current cost from the most recent lot of 35 seeds., Results: During the study, 72 I-125 seed lots were ordered bi-weekly, with a median of 35 seeds per lot (Range: 15-35). Each seed was used on average 2.26 times prior to being discarded. The average duration of each seed lot used was 62.2 days (Range: 21-126). Each seed lot contributed to the construction of an average of 8.4 eye plaques (Range: 2-20). With seed recycling, 2,475 seeds were used to construct 608 eye-plaques. Without re-using practice this would require 5,694 seeds. This resulted in a percentage cost savings of 56.5%, with a total seed cost reduction of $344,884, or $559 per eye-plaque on average., Conclusion: This is the first study to evaluate cost savings relative to re-using I-125 seeds for eye plaques. The data demonstrates how an institution can decrease costs associated with I-125 radiation seeds used for eye-plaque brachytherapy by re-using them., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Background: We report a case of personalized exclusive brachytherapy treatment for the management of a highly recurrent squamous cell conjunctival carcinoma with corneal invasion., Case Description: This is a case of a Caucasian 81-years-old man who presented 10 years ago to our clinic with a pink-white para-limbal mass with dilated feeder arteries and mild leukoplakia. Excisional biopsy confirmed the presence of conjunctival intraepithelial neoplasia (CIN). Successively, he underwent two 4-weeks cycles of Mytomicin C topical therapy and a second excisional surgery, due to several recurrences of the lesion. At the last relapse, the pink-white peri-limbic mass which invaded the corneal limbus, determining corneal opacification from 5- to 7-clock hours, was confirmed by anterior segment optical coherence tomography (AS-OCT). Due to resistance to MMC therapy and chronic epitheliopathy, an AS-OCT guided exclusive radiotherapy plan was set: a Rhutenium-106 CCD plaque was applied directly over the afflicted corneal surface, the corneal limbus and the neighboring sclera for 24 hours. The remission of both conjunctival and corneal malignancy was complete 2 months after surgery and no signs of recurrence were highlighted at AS-OCT analysis at the 2-year follow up., Conclusion: Brachytherapy treatment showed optimal management of both corneal and conjunctival involvement, with a free-of-disease follow-up of 24-months. This result suggests that, in specific conditions, Ru-106 brachytherapy could be an effective option of treatment even if not associated with surgical excision., Competing Interests: Disclosures The authors declare no conflict of interests. This research did not receive any specific grant from funding agencies in public, commercial or not-for-profit sectors., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purposes: In this study we aim to quantitatively evaluate the stability of implanted seeds in permanent breast seed implant (PBSI) brachytherapy and assess any impact on treatment quality., Methods and Materials: Sixty-seven consecutive patients who received PBSI treatment at BC Cancer Kelowna from 2013 to 2021 with post-implant CT images available were included in this study. For each patient, two sets of post-implant CT scans were retrospectively analyzed: Day0, obtained immediately after implant, and Day30, obtained approximately one month following implant. Seed distributions were quantified using the 90% isodose contour, outlier seed maximum spread, and number of seeds located in the seroma as well as seroma quadrants. These were then compared between Day0 and Day30. Post-implant dosimetry of target volumes as well as critical structures were compared., Results: The 90% isodose volume was found to decrease over time. All seeds remained in the breast region however the maximum spread of seeds increased in all directions from Day0 to Day30. All recorded target volume dosimetric parameters were, on average, lower on Day30 compared to Day0 but mean dosimetry levels still met clinical goals. Dose in critical structures was overall similar., Conclusions: In this study, we quantitatively described the changes in seed distributions as well as dosimetry from Day0 to Day30 post PBSI procedure. We addressed concerns related to seed stability in breast tissue and provided clinical evidence on dosimetric efficacy of the PBSI technique., Competing Interests: Acknowledgments The authors would like to thank the support from BC Cancer Foundation and NSERC Discovery Grant (RGPIN-2021-02623)., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate clinical outcomes of CT-based adaptive intracavitary and interstitial brachytherapy (IC followed by IC-ISBT) in locally advanced cervical cancer (LACC) in resource-constrained settings., Methods and Materials: LACC patients treated with adaptive brachytherapy techniques were analyzed to evaluate treatment characteristics and clinical outcomes. The Kaplan-Meier method was used for survival analysis, and the log-rank test for univariate analysis., Results: Out of 141 eligible patients with LACC, 87 (61.7%) patients received external beam radiotherapy (EBRT) in referral hospitals, while 54 (38.3%) were treated at our center. We divided our cohort into two groups: poor EBRT responder group (n = 70 [49.6%]) where IC-ISBT was adapted to achieve optimum tumor doses and OAR optimization group 71 (50.4%) where IC-ISBT was performed to reduce OAR doses. Median HRCTV-D90 dose was 88 Gy (range 70-109 Gy) with median HRCTV volume 33cc (range 15-96). Median D2cc doses to OARs were 90 Gy (range 70-107), 71 Gy (range 55-105) and 70 Gy (range 47-90) to bladder, rectum and sigmoid, respectively. At median follow-up of 32 months, 3-year local control (LC), locoregional control (LRC), disease-free survival (DFS) and overall survival (OS) were 83%, 75%, 64% and 72%, respectively. Subgroup analysis revealed significantly better outcomes for OAR optimization compared to poor EBRT responders, with 3-year LC (95% vs. 70.1%, p < 0.001), LRC (87.3% vs. 62.7%, p < 0.001), DFS (79.2% vs. 49.4%, p < 0.001), and OS (86.2% vs. 57.4%, p < 0.001) CONCLUSION: In resource-constrained settings, implementation of Adaptive IC-ISBT is a viable alternative for optimizing OAR doses in LACC. However proactive approach employing IC-ISBT for tumor dose-escalation from first fraction of BT is warranted for improving LC in poor EBRT responders., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Objectives: To compare survival of patients who received LDR prostate brachytherapy relative to that of peers in the general population of England, UK., Patients and Methods: Net survival was estimated for 2472 cases treated between 2002 and 2016 using population-based analysis guidelines. Life tables adjusted for social deprivation in England from the Office for National Statistics were used to match patients by affluence based on their postcode., Results: The median (range) age at time of brachytherapy was 66 (55-84) years, 84% resided in Southeast England, 51% under an index of deprivation quintile 5 (most affluent), 55% were clinical stage T1 and the remainder T2. Death from any cause occurred in 270 patients at a median (range) of 7 (1-17) years postimplant. Five and 10-year estimates (95% CI) of overall survival were 96% (95-97) and 90% (89-92), and net survival 103% (102-104) and 109% (107-110) respectively. The net survival remained above 100% in all age-at-treatment and clinical stage groups., Conclusion: Net survival above 100% indicates patients survive longer than the matched general population. The study shows for the first time the net survival of patients treated with a radical therapy for localized prostate cancer in England. The impact of treatment choice on the long-term net survival advantage requires further investigation., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Introduction/objectives: The addition of a boost to the lumpectomy bed after whole-breast (WB) radiotherapy plays a key role in the treatment of patients with breast cancer (BC). The clinical benefits of a boost with high-dose-rate brachytherapy (HDR-BT) after conventional fractionation is supported by a large body of evidence. However, few studies have described its outcomes after a hypofractionated scheme., Materials and Methods: We included all patients treated with adjuvant WB-IMRT in 15 sessions followed by a single-session HDR-BT boost with local anesthesia on an outpatient basis., Results: Between 2009 and 2017, 638 patients with early-stage BC were treated according to the aforementioned protocol after breast-conserving surgery. Median follow-up was 6 years (4-11). Despite the low incidence of side effects and their slightness, we did identify an impact of breast volume on the risk of acute radiodermatitis, fibrosis, pain and edema. However, we did not identify any relationship between the volume in cubic centimeters of the BT-implant with acute or long-term side effects. 2.2% patients had an actual local relapse, 2.4% a 2nd primary in the same breast and 2.39% were diagnosed with contralateral BC. Event-free survival at 11 years was 85.5% with an overall survival of 95.7%., Conclusion: Adjuvant hypofractionated whole-breast IMRT followed by a single dose HDR-BT boost has a low incidence of acute and chronic toxicity and excellent oncological outcomes. However, it may be worthwhile to intensify self-care protocols and surveillance in women with large breasts who may be at increased risk of side effects., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Background: Delays in initiating and completing brachytherapy may have adverse oncologic outcomes for patients with cervical, uterine, and prostate cancer. The impact of the COVID-19 pandemic on brachytherapy in the United States has not been well-characterized., Objectives: We aim to evaluate how a positive COVID-19 test affected timeliness of treatment for patients undergoing brachytherapy for cervical, uterine, and prostate cancer., Methods: We queried the National Cancer Database to identify patients diagnosed with cervical, uterine, and prostate cancer in 2019 and 2020 who received brachytherapy in their treatment. Patients who tested positive for COVID-19 between cancer diagnosis and start of radiation were compared to those who did not test positive for COVID-19. Time in days from cancer diagnosis to initiation of radiation was compared using two-sample t-tests with p < 0.05 signifying significant differences., Results: We identified 38,341 patients with cervical (n = 6,925), uterine (n = 18,587), and prostate cancer (n = 12,829). Rates of COVID-19 positivity were cervical cancer (n = 135; 2%), uterine cancer (n = 236; 1.3%), and prostate cancer (n = 141; 1%). Of those, 35% of cervical, 49% of uterine, and 43% of prostate cancer patients tested positive between their cancer diagnosis and initiation of radiation. Median days to radiation was significantly longer in these patients: 78 versus 51 for cervical cancer (p < 0.01), 150 versus 104 for uterine cancer (p < 0.01), and 154 versus 124 for prostate cancer (p < 0.01)., Conclusions: For patients with cervical, uterine, and prostate cancer diagnosed between 2019-2020, testing positive for COVID-19 after their cancer diagnosis was associated with a delay to initiation of radiation by 4-7 weeks., (Published by Elsevier Inc.)

Introduction: The purpose of this prospective randomized trial was to compare the use of a novel vaginal hydrogel packing system (BrachyGel) to standard vaginal packing (VP) during high dose rate (HDR) brachytherapy (BT) for locally advanced cervical cancer (LACC)., Methods: This cross-over study included LACC patients receiving HDR BT boost (intracavitary +/- interstitial). All patients received alternating gauze or BrachyGel VP on Arms A and B. Patients, physicians, and physicists evaluated BT characteristics via a 4-point Likert scale. Adverse events (AEs) were prospectively collected and scored per CTCAE., Results: The 20 patients enrolled. The mean bladder D2cc difference between gauze and BrachyGel in Arm A was 0.117 Gray (Gy) and in Arm B 0.013 Gy. The mean difference in rectum D2cc in Arm A and Arm B was -0.189 Gy and -0.191 Gy, respectively. The mean dose to 90% of the high-risk clinical target volume (HR-CTV) for gauze compared to BrachyGel was -0.032 Gy (95% CI: 0.472, 0.409). Patient-reported discomfort was similar with BrachyGel and gauze ("mild/moderate" 70.0% vs 74.0%, respectively). The clarity of VP was similar between BrachyGel and gauze (86.8% vs 89.7%, respectively). The completeness of VP was more frequently "excellent/good" with BrachyGel (79.0%) compared to gauze (56.4%). The ease of packing was more frequently "extremely easy" with BrachyGel (21.2% vs 0%). No serious AEs were reported., Conclusion: This randomized trial found no clinically significant difference in OAR or HR-CTV dosimetry between BrachyGel and standard VP. BrachyGel performed well compared to gauze for the patient and physician use experience., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Surgical resection remains the only curative therapy for pancreatic cancer. Unfortunately, many patients have borderline or unresectable disease at diagnosis due to proximity of major abdominal vessels. Neoadjuvant chemotherapy and radiation are used to down-stage, however, there is a risk that there will be a positive/close surgical margin. The CivaSheet is a low-dose-rate (LDR) brachytherapy device placed at the time of surgery to target the area of highest risk of margin positivity. The purpose of this study is to assess the clinical value of brachytherapy in addition to standard-of-care therapy in pancreatic therapy., Methods and Materials: Between 2017 and 2022 patients with borderline and locally advanced pancreatic cancer treated with neoadjuvant chemotherapy and radiation followed by surgical resection were included. There were 2 cohorts of patients: (1) Those who had the LDR brachytherapy device placed at the time of surgery and (2) those who did not. Sixteen of 19 (84%) patients who had brachytherapy were enrolled in a prospective clinical trial (NCT02843945). Patients were matched for comorbidities, cancer staging, and treatment details. The primary outcome was progression-free survival (PFS)., Results: Thirty-five patients were included in this analysis, 19 in the LDR brachytherapy group and 16 in the comparison cohort. The 2-year PFS was 21% vs. 0% (p = 0.11), 2-year OS was 26% vs. 13% (p = 0.43), and the pancreatic cancer cause-specific survival was 84% vs. 56% (p = 0.13) in favor of the brachytherapy patients., Conclusions: Use of LDR brachytherapy at the time of resection shows a trend towards improved progression free and overall survival for patients with borderline or locally advanced pancreatic cancer treated with neoadjuvant chemoradiation., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: In this systematic review and meta-analysis, we describe the oncologic and toxicity outcomes of definitive focal brachytherapy for prostate cancer., Methods and Materials: A PROSPERO registered study (CRD42023410170) was conducted following the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) guidelines. PubMed, Embase, and The Cochrane Library were searched for studies between 2000 and 2022. Two authors independently performed the initial search. Biochemical recurrence-free survival (bRFS) was defined as the primary endpoint for the meta-analysis. Generalized linear mixed-effects models were conducted to calculate effect size and quantify heterogeneity. We also describe the side effects and local recurrence patterns of focal brachytherapy., Results: Ten studies were identified and included 315 patients treated using focal brachytherapy as a definitive treatment. Mean (SD) age was 67.65 (7.9) years and mean (SD) PSA was 7.15 (2.7) ng/mL. Most patients (n = 236, 75%) underwent LDR Brachytherapy and 25% received HDR brachytherapy. Among the participants, 147 (46.5%) had a Gleason score ≤6, and 169 (53.5%) had a Gleason score ≥7. Only 11 (3.5%) patients received ADT. Overall, bRFS rate at median follow-up 4 years (Range: 1-6.42 years) was 91% (95% confidence interval [CI], 82-95%). Acute Grade ≤ 2 GU and GI toxicities were reported in 22 (7%) and 11 (3.5%) patients, respectively. Late Grade ≤ 2 GU and GI toxicity were reported in 6 (2%) and 14 (4.4%) patients, respectively. One case of prostate hemorrhage due to improper foley removal was noted but otherwise no acute or late Grade 3 or higher GI or GU toxicity related to radiotherapy was reported., Conclusion: Overall, definitive focal brachytherapy has a favorable toxicity profile. Oncologic outcomes are yet to mature. The evidence is limited by the small number of studies with low patients' number, across study heterogeneity, and possibility of publication bias., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Background and Purpose: Although MRI-based image guided adaptive brachytherapy (IGABT) for locally advanced cervical cancer (LACC) has resulted in favorable outcomes, it can be logistically complex and time consuming compared to 2D image-based brachytherapy, and both physically and emotionally intensive for patients. This prospective study aims to perform time-action and patient experience analyses during IGABT to guide further improvements., Materials and Methods: LACC patients treated with IGABT were included for the time-action (56 patients) and patient experience (29 patients) analyses. Times per treatment step were reported on a standardized form. For the patient experience analysis, a baseline health status was established with the EQ-5D-5L questionnaire and the perceived pain, anxiety and duration for each treatment step were assessed with the NRS-11., Results: The median total procedure time from arrival until discharge was 530 (IQR: 480-565) minutes. Treatment planning (delineation, reconstruction, optimization) required the most time and took 175 (IQR: 145-195) minutes. Highest perceived pain was reported during applicator removal and treatment planning, anxiety during applicator removal, and duration during image acquisition and treatment planning. Perceived pain, anxiety and duration were correlated. Higher pre-treatment pain and anxiety scores were associated with higher perceived pain, anxiety and duration., Conclusion: This study highlights the complexity, duration and impact on patient experience of the current IGABT workflow. Patient reported pre-treatment pain and anxiety can help identify patients that may benefit from additional support. Research and implementation of measures aiming at shortening the overall procedure duration, which may include logistical, staffing and technological aspects, should be prioritized., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: With the emergence of imaged-based planning and hybrid applicators the complexity of gynecologic brachytherapy has dramatically increased. Despite the known advantages of brachytherapy, notable national declines in utilization of brachytherapy have been documented. Clearly improved education in the sphere of gynecologic brachytherapy is needed. We hypothesize that a hands-on applicator-based training session would improve trainee comfort with gynecologic brachytherapy., Methods and Materials: An in-person, applicator-based, hands-on training session was held with trainees from both radiation and gynecologic oncology programs. Trainees practiced assembling and handling applicators while receiving instruction on clinical scenarios in which various applicators are used in gynecologic cancer brachytherapy. Pre- and post-session, participants were administered an objective test of 10 pictorial-based case vignettes to quantify ability to select the correct applicator based on the interpretation of T2-weighted MR images. Participants additionally received a subjective survey to quantify comfort and experience with gynecologic brachytherapy using Likert-type question formatting., Results: A total of 14 trainees participated. Most common case volume experience was 0-10 intracavitary (57%), 0-10 hybrid (71%), and 0-10 interstitial (71%). Pre-session, the most common answer to comfort level was "not comfortable still learning" for all brachytherapy types, and most common answer to largest gap in knowledge was all facets of brachytherapy. Average case-based test score was 3.5/10 pre-session versus 5.3/10 post-session (p = 0.028). Post-session, all respondents reported improved comfort level with brachytherapy. Post-session, most common answer to largest gap in knowledge was applicator/patient selection, and applicator/patient selection was also the largest area of identified improvement. 100% of participants felt repeating the session in the future would be helpful., Conclusions: Hands-on training with applicators improves both subjective and objective comfort with gynecologic brachytherapy. With 100% of participants requesting to implement this session into resident training, we suggest national opportunities might exist to expand educational processes and improve utilization of complex gynecologic brachytherapy in practice., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Brachytherapy is a critical component of the standard-of-care curative radiotherapy regimen for women with locally advanced cervical cancer (LACC). However, existing literature suggests that many patients will not receive the brachytherapy boost. We used machine learning (ML) and explainable artificial intelligence to characterize this disparity., Materials and Methods: Patients with LACC diagnosed from 2004 to 2020 who received definitive radiation were identified in the National Cancer Database. Five ML models were trained to predict if a patient received a brachytherapy boost. The best-performing model was explained using SHapley Additive exPlanation (SHAP) values. To identify trends that may be attributable to the coronavirus disease 2019 (COVID-19) pandemic, the previous analysis was repeated and limited to 2019 to 2020., Results: A total of 37,564 patients with LACC were identified; 5799 were diagnosed from 2019 to 2020 (COVID cohort). Of these patients, 59.3% received a brachytherapy boost, with 76.4% of patients diagnosed in 2019 to 2020 receiving a boost. The random forest model achieved the best performance for both the overall and COVID cohorts. In the overall cohort, the most important predictive features were the year of diagnosis, stage, age, and insurance status. In the COVID cohort, the most important predictive features were FIGO stage, age, insurance status, and hospital type. Of the 26 patients who tested positive for COVID-19 during their course of radiotherapy, 19 (73.1%) received a brachytherapy boost., Conclusions: A gradual increase in brachytherapy boost utilization has been noted, which did not seem to be significantly impacted by the onset of the COVID-19 pandemic. ML could be considered to identify patient populations where brachytherapy is underutilized, which can provide actionable feedback for improving access., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

Purpose: For second ipsilateral breast tumor event (2ndIBTE), conservative treatment (CT) involving wide local excision plus accelerated partial breast reirradiation (APBrI) is increasingly used as an alternative to mastectomy. This study investigates the impact of APBrI technique and multicatheter interstitial high dose-rate brachytherapy (MIB) dosimetry parameters on toxicity and survival in patients with 2ndIBTE., Materials-Methods: Data from patients with 2ndIBTE treated with CT, were analyzed. Inclusion criteria specified 2ndIBTE occurring at least one year after 1st CT for primary breast cancer. Treatment details and dosimetry parameters were recorded. Primary endpoint was late toxicity. Secondary endpoints were late toxicity prognostic factors analysis and oncological outcome., Results: From 07/2005 and 07/2023, 201 patients (pts) received 2nd CT. With a median follow-up of 49.6 months (44.9-59.5), tumor size was less than 2 cm (88.1%), with estrogen receptor positive (92.7%). Patients were low (63.7%) or intermediate (29.8%) GEC-ESTRO APBI risk classification. Late toxicities were observed in 34.8% (G1 52.3%, G2 40.7%). Cutaneous fibrosis was the most common toxicity. Cosmetic outcomes were excellent in 64.1%. Dosimetry analysis revealed positive correlations between complications and absolute volumes of CTV, V100, V150, and V200. Volumes requiring higher needle number and lower DNR resulted in fewer complications. 5-year disease-free and overall survival were 88% and 95% respectively., Conclusion: Second CT for 2ndIBTE showed favorable oncological outcomes and survival rates. Complications were correlated with specific dosimetric parameters, emphasizing the importance of tailored treatment planning. This study provides valuable insights in risk stratification and MIB optimization for APBrI., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)