Eligible breast cancer patients with mastectomy and axillary dissection are divided into two groups: conventional fractionated (CF) radiotherapy of 50 Gray (GY) in 25 fractions within 5 weeks to ipsilateral chest wall and supraclavicular nodal region, and hypofractionated (HF) radiotherapy of 43.5 Gray (GY) in 15 fractions within 3 weeks to the same region. During and after radiotherapy , the patients are followed and the efficacy and toxicities of radiotherapy are evaluated.
The purpose of this study is to compare the efficacy and toxicities of hypofractionated radiotherapy with conventional fractionated radiotherapy in high risk breast cancer patients treated with mastectomy. It's hypothesized that the efficacy and toxicities are similar between the two groups.