Simultaneous Integrated Boost in Once-weekly Hypofractionated Radiotherapy for Breast Cancer in the Elderly: Preliminary Evidence

Aim: To evaluate once-weekly hypofractionated radiotherapy in elderly patients affected by early breast cancer, reporting acute and late toxicity profiles, and treatment feasibility. Patients and Methods: Fifty patients were treated with a hypofractionated regimen: 28.5±2.5 Gy in five fractions at one fraction weekly. Simultaneous integrated boost (SIB) to the tumor bed in high-risk cases. Inclusion criteria: patients over 70 years old, pT1-2, N0-1a. Acute and late toxicities were assessed based on Radiation Therapy Oncology Group. Results: The median follow-up was 20 months and the median patient age was 79 years. SIB was added for 22 patients (44%). Grade 3-4 acute cutaneous toxicities were not observed; grade 2 toxicity occurred only in four patients (8%). Late subcutaneous tissue toxicity consisted of grade 2 fibrosis in two patients (4%), grade 1 in five (10%) and grade 0 in 41(85%). Conclusion: Limiting fraction numbers with a safer profile may improve the management of breast cancer for the elderly.