Prognostic Value of Lymph Node Ratio in Breast Cancer Patients with Adequate Pathologic Evidence After Neoadjuvant Chemotherapy.

BACKGROUND The prognostic role of axillary lymph node ratio (LNR) after neoadjuvant chemotherapy (NAC) in breast cancer has not been illuminated. This study was designed to investigate the prognostic role of LNR in breast cancer compared with traditional ypN stage. MATERIAL AND METHODS A total of 306 breast cancer patients diagnosed with positive axillary lymph nodes from January 2007 to December 2014 were eligible for this retrospective analysis. All enrolled patients were treated with a median of 4 cycles of NAC followed by mastectomy and level I, II, and III axillary lymph node dissection (ALND). RESULTS The median duration of follow-up was 78 months (range, 7-147 months). Univariate analysis indicated that both the LNR category (P<0.001) and ypN stage (P<0.001) were significant associated with event-free survival (EFS) and overall survival (OS). However, multivariate analysis indicated that the LNR category was independently associated with EFS (P<0.001) and OS (P<0.001), while the ypN stage showed no statistical effect on EFS (P=0.391) or OS (P=0.081). On additional analyses stratified by molecular subtypes, we found that the prognosis of triple negative breast cancer could be better discriminated when the cutoff value of LNR was set at 0.15. CONCLUSIONS LNR showed a superior predictive value in evaluating prognosis of breast cancer patients after NAC. In addition, the LNR cutoff point 0.15 can accurately discriminate survival outcomes for different triple negative breast cancer subtypes.