Evaluating the Prediction of Breast Cancer Survival Using Lymph Node Ratio

PURPOSE: Previous oncological studies showed that lymph node ratio (LNR) (ratio of number of lymph nodes that tested positive for metastasis to the total number of lymph nodes examined) is a negative indicator of cancer survival. The American Joint Committee on Cancer (AJCC) staging system incorporates tumor size, lymph node involvement, and metastasis in a comprehensive model of cancer progression, but LNR alone has been shown to outperform the AJCC system in prognostic and survival predictions for various types of cancer. The effectiveness of LNR has not been evaluated in breast cancer staging. Evaluating LNR for predicting cancer staging in breast cancer has the potential to improve treatment recommendations. METHODS: The Surveillance, Epidemiology, and End Results dataset was used to identify 10,655 breast cancer patients who underwent nodal evaluation from 2010 to 2013, and their LNRs were calculated. Descriptive statistics of lymph node evaluation in the patients are provided. Logistic regression with LNR as the continuous independent variable was conducted to determine whether LNR could predict cancer progression, coded as regional or distant. Analysis was conducted using SPSS version 24. RESULTS: Patient's mean age was 59.43±18.62. Logistic regression analysis revealed that for every 1.3% increase in LNR, the odds of falling into the distant stage of the TNM staging system increased by 13.7% (odds ratio, 14.73; 95% confidence interval, 12.00–18.08). CONCLUSION: LNR, while correlated with breast cancer staging, serves as a better predictor of survival. Precision staging can influence treatment modality, and improved treatments can significantly improve quality of life. Additional research and diagnostic examinations using LNR as a potential tool for accurate staging in breast cancer patients are warranted.