Hypofractionated Whole-breast Irradiation With Simultaneously Integrated Boost For Early-Stage Breast Cancer After Breast-conserving Surgery

Inclusion Criteria: * Female * 18-60 years old * Treated with breast conversing surgery and sentinel lymph node biopsy or axillary lymph node dissection * Pathologically confirmed invasive breast cancer * A pathological T1-2N0M0 tumor * Tumor bed is labeled with Titanium clips * Negative surgical margins * Written informed consent. Exclusion Criteria: * KPS\<70 * Treated with neoadjuvant chemotherapy * Sentinel lymph nodes only containing isolated tumour cells (\<0.2 mm) * With severe comorbidity * Previous breast cancer or other malignant tumor history * Previous radiotherapy for breast or thorax * Medical contraindication for radiotherapy * Pregnant or nursing