The value of positive lymph nodes ratio combined with negative lymph node count in prediction of breast cancer survival

Background: Positive lymph node ratio (LNR), defined as ratio of positive lymph nodes to all lymph nodes removed, is a powerful prognostic factor in invasive breast cancer. Here we focused on the impact of negative lymph node (NLN) count on the prediction of value of LNR in breast cancer survival. Methods: Of 929 invasive breast cancer patients were enrolled in our retrospective study. We use Kaplan-Meier to calculate the 5-year overall survival (OS) according to different clinicopathologic parameters. The prediction value of NLN count and LNR in OS was examined. Results: The optimal cutoff of NLN count was designated as 9. Five-year OS was 77.0% and 95.0% in patients with NLN of 0-9 and >= 10, respectively (P<0.001). Among 204 patients who had 0-9 NLN, 25 patients with LNR 0-20.0% had 5-year OS of 95.7%, 104 patients with LNR 20.1-65.0% had 5-year OS of 83.4%, and 75 patients with LNR 65.1-100.0% had 5-year OS of 61.7% (P<0.001); Among 725 patients who had NLN >= 10, 650 patients with LNR 0-20.0% had 5-year OS of 96.1%, 68 patients with LNR 20.1-65.0% had 5-year OS of 86.8%, and 7 patients with LNR 65.1-100% had 5-year OS of 71.4% (P<0.001). Conclusions: High NLN count is associated with improved survival in invasive breast cancer patients. Combining NLN count with LNR could be considered as an alternative to LNR alone in prediction of postoperative breast cancer survival.