The present study showed that the 7-year overall incidence of LRR was 3.8% in patients with pT1-2N0 breast cancer treated with mastectomy but not PMRT. Additionally, the 7-year LRR rate of patients aged less than or equal to 40 years with T2 tumors, who were considered at high risk, was 12.4%. Since no LRR was reported after 7 years, the LRR rate at 7-year and 10-year were identical (Figure 1). These results are in agreement with those of recent studies (Table 4).