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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.
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PURPOSE: To quantify the relative motion of pelvic and groin lymph nodes (PLN and GLN) and define indicative margins for image-guided radiotherapy based on bony anatomy for the frog-leg position (FLP) and groin immobilization board (GIB). MATERIALS AND METHODS: Twenty patients with planning computed tomography (CT) scan and on treatment cone beam CTs (median = 8) for groin and pelvic radiotherapy were included in the study. Of these nine were treated with FLP and eleven with GIB. The PLN and GLN regions on the left and right were outlined in each scan. Systematic and random uncertainties were determined along with correlations between the motions of these regions. The clinical target volume to planning target volume (PTV) margins required to take motion into account was calculated for each immobilization. RESULTS: The mean shifts for PLN and GLN were lesser but not statistically lower using GIB over FLP. There was significant concordance in the vertical, longitudinal and lateral motion of the pelvis and right groin (P = 0.015, 0.09 and 0.049, respectively), pelvis and left groin (P = 0.001, 0.048, and 0.006, respectively) and between left and right groin (P = 0.013, 0.01 and 0.07, respectively) for FLP and not GIB. The PTV margins required by Van Herk and Stroom's formula were reduced from 11 mm and 9 mm to 6 mm and 5 mm for pelvis; 12 mm and 11 mm to 7 mm and 6 mm for groin, respectively, using FLP over GIB. CONCLUSIONS: GIB brings concordance in shifts between pelvis and groin and between bilateral groins, thereby reducing the required PTV margins.
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PURPOSE: The purpose of the study was to report dosimetric differences for breast brachytherapy plans optimized for clinical target volume (CTV) generated using conventional isotropic expansion of tumor bed volume (TBV) and Groupe Européen de Curiethérapie-European Society for Radiotherapy and Oncology (GEC-ESTRO) recommendations to expand the TBV anisotropically to achieve a total safety margin of 2 cm (resection margin size + added safety margin). METHODS: Institutional records of 100 patients who underwent accelerated partial breast irradiation using multicatheter interstitial brachytherapy from May 2015 to March 2020 were reviewed retrospectively. Two sets of CT-based plans were made, one with 1-cm isotropic margins around the tumor bed (CTV_ISO) and the other with anisotropic margins (CTV_GEC). Plans were evaluated and compared using the American Brachytherapy Society and GEC-ESTRO guidelines. RESULTS: The median TBV was 36.97 cc. The median margin widths were as follows: anterior 1.2, posterior 1.0, superior 1.0, inferior 0.9, medial 1.2, and lateral 1.2 cm. The mean tumor bed coverage index was 0.94; 0.93 [p.066], the CTV coverage index 0.86; 0.84 [p 0.001], the dose homogeneity index (DHI) 0.77; 0.75 [p < 0.001] and the conformity index 0.66; 0.64 [p < 0.001] in CTV_ISO and CTV_GEC plans, respectively. In smaller volume implants (TBV< 35 cc), the DHI was 0.76; 0.75 [p 0.008] and the conformity index was 0.66; 0.62 [p < 0.001], whereas in larger volumes >35 cc, the CTV coverage index was 0.86; 0.84 [p 0.003] and the DHI 0.78; 0.76 [p 0.001] in CTV_ISO and CTV_GEC plans, respectively. CONCLUSIONS: In this cohort of patients who underwent accelerated partial breast irradiation, plans with anisotropic margins had lower conformity, the impact of which was predominantly seen in smaller implants. Rest of the dosimetric constraints were achieved in both the plans as per the American Brachytherapy Society and GEC-ESTRO guidelines.