Omitting radiotherapy is safe in breast cancer patients ≥ 70 years old after breast-conserving surgery without axillary lymph node operation

Abstract To verify whether omitting radiotherapy from breast cancer treatment for patients ≥ 70 years old following breast-conserving surgery (BCS) without axillary lymph node dissection is safe. Previous studies have shown that omitting breast radiotherapy after BCS and axillary lymph node dissection is safe for elderly breast cancer patients. We aimed to evaluate the safety of BCS without axillary surgery or breast radiotherapy (BCSNR) in elderly patients with breast cancer and clinically negative axillary lymph nodes. We performed a retrospective analysis of 481 patients with breast cancer, aged ≥ 70 years, between 2010 and 2016. Of these, 302 patients underwent BCSNR and 179 underwent other, larger scope operations. Local recurrence rate, ipsilateral breast tumor recurrence (IBTR) rate, distant metastasis rate, breast-related death, disease-free survival (DFS), and overall survival (OS) were compared between the two groups. After a median follow-up of 60 months, no significant differences in local recurrence, distant metastasis rate, breast-related death, and DFS were noted. The OS was similar (P = 0.56) between the BCSNR group (91.7%) and other operations group (93.0%). The IBTR rate was considered low in both groups, however resulted greater (P = 0.005) in the BCSNR group (5.3%) than in other operations group (1.6%). BCSNR did not affect the survival of elderly patients with breast cancer with clinically negative axillary lymph nodes. IBTR was infrequent in both groups; however, there was a significant difference between the two groups. BCSNR is a feasible treatment modality for patients with breast cancer ≥ 70 years old with clinically negative axillary lymph nodes.