Lymph node density as an independent prognostic factor in node-positive patients with tonsillar cancer.

BACKGROUND The purpose of this study was to evaluate the utility of lymph node density for predicting the survival of patients with tonsillar cancer and positive neck nodes. METHODS We reviewed data for 64 patients diagnosed with tonsillar cancer with lymph node metastasis in a retrospective single center audit. RESULTS Lymph node density (≥0.05), extracapsular spread (ECS), number of ECS (≥3), vascular invasion, perineural invasion, and N classification (N1/N2a vs N2b/N2c) were significant predictors of 5-year disease-free survival (DFS). Lymph node density (≥0.05), human papillomavirus (HPV) infection, and N classification (N1/N2a vs N2b/N2c) were significant predictors of 5-year overall survival (OS). In the multivariate analysis, categorical lymph node density remained a significant predictor of DFS (p = .025*; hazard ratio [HR] = 6.063) and no parameter was significantly predictive of OS. CONCLUSION Lymph node density might be useful as an independent predictor of survival in patients with tonsillar cancer and positive lymph nodes. © 2015 Wiley Periodicals, Inc. Head Neck 38: E705-E711, 2016.