Abstract
PurposeTo assess feasibility of accelerated hypofractionated radiotherapy with simultaneous integrated boost (SIB) with volumetric modulated arc technique (VMAT) in patients with breast cancer.Methods Total 27 patients after breast conserving surgery (BCS) were included in this study. Patients were planned on 4-dimensional computerized tomogram (4D-CT) and contouring was done using RTOG guidelines. Dose delivered was 34 Gy/10#/2wk to the breast and 40 Gy/10#/2wk to the tumor bed as SIB with VMAT technique. The primary endpoint was grade 2 acute skin toxicity. Doses to the organs at risk were calculated. Toxicities and cosmesis were assessed using RTOG LENT-SOMA and HARVARD/NSABP/RTOG grading scales, respectively. Disease-free survival (DFS) and overall survival (OS) was calculated with Kaplan Meier curves.ResultsMean age of the patients was 42 years. Left and right breast cancer was seen in 17 (63%) and 10 (37%) patients, respectively. Ipsilateral lung mean V16 and contralateral lung V5 was 16.01% and 3.73%, respectively. Mean heart dose from the left and right breast was 7.25Gy and 4.37Gy, respectively. Mean dose to the contralateral breast, oesophagus and spinal cord was 2.64Gy, 3.69Gy and 3.15Gy, respectively. Thyroid V25 mean was 19.69%.Grade 1 and 2 acute skin toxicity was observed in 9 (33%) and 5 (18.5%) patients, respectively. Grade 2 hyperpigmentation, edema and induration were observed in 1 (3.7%), 2 (7.4%) and 4(14.8%) patients, respectively. Mild breast pain and arm/shoulder discomfort were reported by 1 (3.4%) patient each. Median follow-up was 48 months (range 12-58 months). At 4 years breast induration, edema and fibrosis each were observed in 1(3.7%) patient. Cosmesis was excellent and good in 21 (78%) and 6 (22%) patients, respectively. Local recurrence and distant metastases occurred 1(3.7%) and 2(7.4%) patients, respectively. DFS and OS at 3-years was 88% and 92%, respectively.ConclusionWith this RT schedule acute and late toxicity rates were acceptable with no adverse cosmesis. Local control, DFS and OS were good.
Analysis of safety of postoperative accelerated hypofractionated radiotherapy for patients with stage I-IIIA breast cancer
