Association of Breast Cancer Subtypes and Clinicopathological Factors with Axillary Lymph Node Positivity Amongst Women with Breast Cancer in Rajasthan: An Observational Analytical Study.

Abstract

Prognostic factors by definition, are capable of providing information on clinical outcomes at the time of diagnosis, independent of therapy. The number of positive lymph nodes (number of ipsilateral axillary nodes with metastatic tumour deposits) is a strong and independent prognostic factor in breast cancer. In a meta-analysis (New England Journal of Medicine, 2017) of over 62,000 patients, the risk of distant recurrence over years 5 to 20 for those with T1 tumours was 13% in the absence of lymph node involvement, 20% among those with one to three involved lymph nodes, and 34% among those with four to nine involved nodes. In this study, we analyzed the association of clinicopathological factors and breast cancer subtypes with axillary lymph node (ALN) positivity in women with breast cancer in Rajasthan. A multivariate Logistic (Ordinal) Regression Model was used to predict the number of positive lymph nodes based on independent variables that showed 90% significance in bivariate analysis, such as total number of lymph nodes dissected, tumour necrosis, and lymphovascular invasion. The Wald criterion indicated that only LVI had a significant impact on the prediction (p < 0.05), while tumour necrosis and the total number of lymph nodes dissected were not significant predictors (p > 0.05). Patients with LVI had a 43.47 times higher risk of having positive lymph nodes (p < 0.05). Early prediction of lymph node metastasis through LVI testing can help in prognostication. Breast cancer subtypes should not be a criterion while deciding lymph nodal management.