Hypofractionated Irradiation At Regional Nodal Area for Breast Cancer Vs Existed Standard Treatment

Investigators hypothesize that hypofractionated radiotherapy is equally effective and safe as conventional radiotherapy in breast cancer patients with an indication for regional nodal irradiation. Eligible breast cancer patients are randomized 1:1 into the following two groups: hypofractionated radiotherapy of 2.67 Gy for 16 fractions (and sequential tumor bed boost of 2.67 Gy for 4 fractions in patients with intact breast) and conventional radiotherapy of 2Gy for 25 fractions (and sequential tumor bed boost of 2 Gy for 5 fractions in patients with intact breast). The dose was prescribed to ipsilateral chest wall or whole breast and regional lymph regions (including supraclavicular and internal mammary lymph nodes). All patients are treated with IMRT. The primary endpoint is locoregional recurrence. Patients will be followed at least 5 years after radiotherapy to evaluated over survival, distant metastasis, toxicity and life quality.