Does the metastatic lymph node ratio influence the disease-free survival of patients with breast cancer: Single-center experiences

Background: Axillary lymph nodes (ALNs) are the most important prognostic factor for survival in breast cancer. Pathological evaluation can affect the number of involved lymph nodes. In the current study, we evaluated whether the metastatic lymph node ratio (n ratio) is important in predicting disease-free survival (DFS) for breast cancer patients. Material and Methods: From 802 breast cancer cases, 427 patients with ALN metastasis were analyzed retrospectively. The n ratio was categorized as n ratio 1 (1-10%), n ratio 2 (10.01-50%) and n ratio 3 (>50%). DFS was established according to the Kaplan-Meier method. Predicting risk factors for relapse were analyzed using the Cox proportional hazards model. Results: The n ratio was significantly higher in breast cancer patients with advanced pathologic pT, pN and clinical stage, undifferentiated histology, lymphovascular and extracapsular invasion, more resected ALNs and positive progesterone receptor. In the univariate analysis, multicentricity, necrosis, grade, pN stage, estrogen receptor and progesterone receptor positivity, trastuzumab and neoadjuvant chemotherapy usage, the presence of inflammatory breast cancer and n ratio were found to be important factors in predicting DFS. Multivariate analysis indicated that multicentricity, neoadjuvant chemotherapy, trastuzumab usage and n ratio were significantly associated with prognosis. Conclusions: The n ratio is inexpensive, easily available and a simple prognostic factor for breast cancer patients with positive ALNs.