The randomization is between 50 Gy / 25 fractions and 42.5 Gy/16 fractions, 5 fractions weekly.~Eligible breast cancer patients with mastectomy and axillary dissection will be randomized 1:1 into two groups: conventional fractionated (CF) radiotherapy of 50 Gy / 25 fractions and hypofractionated (HF) radiotherapy of 42.5 Gy/16 fractions, 5 fractions weekly.~The primary endpoint is loco-regional recurrence. Other cancer related events and acute/late radiation morbidities will also be evaluated. The patients will be followed for 10 years.~It is hypothesized that for women operated for high risk breast cancer with indication of postmastectomy adjuvant radiotherapy, hypofractionated radiotherapy is noninferior to conventional fractionated radiotherapy in terms of the efficacy and toxicities.
The study was designed to investigate whether hypofractionated adjuvant radiotherapy is noninferior to conventionally fractionated adjuvant radiotherapy in terms of efficacy and toxicities for high risk breast cancer patients treated with mastectomy