1:1 randomization to the control group and experimental group, stratified by the type of surgery (breast-conserving surgery (BCS) versus mastectomy) and the type of histologic type (triple negative breast cancer (TNBC) versus non-TNBC)~The control group:~If patients received BCS, WBI+Regional RT~If patients received mastectomy, PMRT~The experimental group:~If patients received breast conserving surgery, WBI alone~If patients received mastectomy, No PMRT
This study is a multicenter, randomized, phase 3 clinical trial in patients with breast cancer, randomizing radiotherapy group (postmastectomy radiation therapy (PMRT)/whole breast irradiation plus regional radiotherapy (WBI+regional RT) versus and no PMRT/WBI alone group. This is a non-inferiority study aiming that there is no significant difference in the 7-year disease-free survival rate between the two groups.