Inclusion Criteria:  Female patients Invasive breast cancer confirmed by pathology Underwent mastectomy and breast reconstruction Radiotherapy after breast reconstruction ECOG score 0-1 Signed informed consent  Exclusion Criteria:  Previous breast or chest radiotherapy Other serious skin diseases (systemic lupus erythematosus, skin sclerosis, et al) and cannot receive radiotherapy Pregnant women Patients who are unwilling or unable to receive regular follow-up.