Dosimetric benefit and clinical feasibility of deep inspiration breath-hold and volumetric modulated arc therapy-based postmastectomy radiotherapy for left-sided breast cancer

作者：Shijia Wang, Shi-Jia Wang, Yi-Rui Zhai, Wen-Wen Zhang, Siye Chen, Shi-Rui Qin, Yu Tang, Yu Tang, Yong-Wen Song, Yueping Liu, Bo Chen, Shunan Qi, Yuan Tang, Ning-Ning Lu, Ye-Xiong Li, Hao Jing, Shulian Wang, Shulian Wang · 发表于：Scientific Reports · 年份：2024 · DOI：10.1038/s41598-024-75560-5 · 被引用次数：7 · 研究领域：Breast Cancer Treatment Studies、Advanced Radiotherapy Techniques、Breast Lesions and Carcinomas

To evaluate the dosimetric benefits and clinical feasibility of deep inspiratory breath-hold (DIBH) combined with volumetric modulated arc therapy (VMAT) in left-sided postmastectomy radiotherapy (PMRT). Eligible patients with left-sided breast cancer undergoing DIBH-based PMRT were prospectively included. Chest wall, supra/infraclavicular fossa, and/or internal mammary node irradiation (IMNI) were planned with a prescription dose of 43.5 Gy in 15 fractions. VMAT plans were designed on free breathing (FB)—and DIBH-CT to compare dosimetric parameters in heart, left anterior descending artery (LAD) and lung. Cone-beam computed tomography (CBCT) was performed before and after treatment to evaluate inter- and intra-fractional setup errors. Heart position and dose variations during treatment were estimated by fusing CBCT with DIBH-CT scans.Twenty patients were included with 10 receiving IMNI. In total, 193 pre-treatment and 39 pairs pre- and post-treatment CBCT scans were analyzed. The D mean , D max , and V 5−40 of the heart, LAD, and left lung were significantly lower in DIBH than FB ( p < 0.05 for all), except for V5 of LAD ( p = 0.167). The cardiopulmonary dosimetric benefits were maintained regardless of IMNI. The inter- and intra-fractional setup errors were < 0.3 cm; and the overall estimated PTV margins were < 1.0 cm. During treatment, the mean dice similarity coefficient of heart position and the mean ratio of heart D mean between CBCT and DIBH-CT plans was 0.95 (0.88–1.0...