Impact of GBBS algorithm on post-mastectomy scar boost irradiation of breast using catheter flap

• Published in: Journal of contemporary brachytherapy Vol. 13; no. 3; pp. 310 - 317
• Main Authors: Sinnatamby, Mourougan, Neelakandan, Vijayaprabhu, Karunanidhi, Gunaseelan, Kandasamy, Saravanan, Ramapandian, Seenisamy, Kannan, Muniyappan, Sampath, Elakiya
• Format: Journal Article
• Language: English
• Published: Poland Termedia Publishing House 01.06.2021
• Subjects: acuros® bv; catheter flap; chest wall; gbbs; Original Paper; scar boost; surface mould; chest wall; Acuros® BV; catheter flap; scar boost; GBBS; surface mould
• ISSN: 1689-832X; 2081-2841
• DOI: 10.5114/jcb.2021.106288

Post-mastectomy radiation therapy significantly reduces locoregional recurrence rates, which can be achieved with external beam radiotherapy delivered to chest wall, followed by scar irradiation either by electron or high-dose-rate (HDR) mould brachytherapy. The present study evaluates dosimetric advantage of Acuros BV, a TG-186 MBDCA, over TG-43 formalism using Ir source for HDR brachytherapy in chest wall scar boost using catheter flap. A total of 25 patients, free of cardiac and pulmonary co-morbidities, who met the inclusion criteria were involved in the study. Catheter flap made of silicon with 20 channels was used to deliver a total dose of 7.5 Gy/3 fx by HDR surface mould brachytherapy to delineated scar volume. Plan was optimized with iterative method to obtain desired results with TG-43 formalism, followed by Acuros BV (GBBS algorithm) without altering dwell positions or time. The two algorithm plans were analyzed qualitatively and quantitatively with dose-volume histograms. The mean D CTV-HDR_evl coverage decreased by 1.16% compared to TG-43, and near-maximum dose decreased by 8.18% ( = 0.000), mean D dose to CTV-HDR_evl, and mean D dose was lesser by 6.25% ( = 0.000) and 10.82% ( = 0.000), respectively, compared to TG-43. Heart D showed significant results, whereas D (cGy) revealed very significant difference. A 5 mm thick skin contour showed statistically significant results ( = 0.000) for V and V . The presented data showed how Acuros BV, algorithm-based calculation in scar boost irradiation of breast, accounting for a mass density of the medium and scatter condition, considered actual dose prediction in a medium.