[Influence of the number of removed axillary lymph nodes on the prognosis of node-negative primary breast cancer]

Abstract

Objective: To analyze the relationship between the number of removed axillary lymph nodes and prognosis of axillary node-negative breast cancer.

Methods: The clinicopathological data of 655 patients with breast cancer were analyzed retrospectively. The disease-free survival curves were generated according to the number of removed axillary lymph nodes using Kaplan-Meier plots. The correlation between the co-variables and rate of breast cancer-related events was analyzed using Cox model.

Results: The overall five year-disease free survival rate of the 655 cases was 94.4%. The rate of patients with lymph node number ≤ 12 was 90.3%, and that of lymph node number > 12 was 96.5%, with a statistically significant difference (P = 0.009). Significantly less breast cancer-related events were observed in patients with lymph node number > 12 (15/426, 3.5%) than that in patients with lymph node number ≤ 12 (22/229, 9.6%) (P = 0.009).

Conclusions: When axillary node dissection is indicated, dissection of lymph nodes >12 leads to much less breast cancer-related events than that in patients with dissected lymph node ≤ 12. The more lymph nodes are dissected, the more accurate prognosis can be estimated.