The Impact of Radiotherapy Boost Dose Delivery in Breast Cancer Treatment on Acute Skin Reactions and Cosmetic Outcome: A Randomized Trial of Sequential and Concomitant Schedules Boost

Background: Minimizing the overall treatment time is an issue of great importance in cancer management. Concomitant boost is a way of decreasing the overall treatment time in breast cancer. The present prospective randomized study aimed to evaluate the feasibility and toxicity and cosmetic outcome of concomitant weekly boost in patients with breast cancer.Method: Patients with breast cancer who underwent breast conservation surgery and were referred to our Radiation Oncology department from 2018 to 2019 were included in this randomized clinical trial. They were randomized to two groups both of which received conventional (50 Gy in 25 fraction, 5 days a week) whole breast irradiation (WBI) with 10 Gy boost dose to lumpectomy cavity. The boost dose in one group (n = 40) was delivered concomitantly on the 6th day of each week. The other group (n = 42) received the boost dose sequentially after completion of conventional WBI. Skin toxicity and cosmetic outcome was compared between the two groups according to CTCAE-4 skin complications and Harvard criteria. Results: We did not observe any significant differences between the sequential and concomitant groups in terms of acute skin reaction within and one month after completion of radiotherapy. After one year of follow-up, no significant differences were seen concerning the cosmetic outcome between the two groups. No local recurrence was observed after 22 months of follow-up.Conclusion: Accelerated radiotherapy with weekly concomitant boost in breast cancer patients was found to be feasible with an acceptable toxicity profile and cosmetic outcome during one year of follow-up.