Prognostic significance of lymph node density in squamous cell carcinoma of the tongue

Background. The prognostic significance of lymph node density in oral squamous cell carcinoma (OSCC) has been well recognized. However, its use in a specific subsite of the tongue has not been evaluated. The purpose of this study was to determine the prognostic significance of lymph node density in tongue squamous cell carcinoma (SCC). Methods. A retrospective analysis of 99 patients with tongue SCC who underwent primary curative resection and neck dissection was conducted. Overall survival (OS) and disease-specific survival (DSS) was used to evaluate the prognostic significance of lymph node density. Results. Lymph node density (using a cutoff of 0.06) was shown to be an independent predictor of OS and DSS. The impact of lymph node density on OS and DSS remained significant on multivariate analysis, whereas conventional nodal staging was not. An alternative staging strategy incorporating depth of invasion and lymph node density performs better than conventional TNM staging in predicting survival. Conclusion. Our data suggest that lymph node density is a reliable and applicable predictor of prognosis in patients with tongue SCC. (C) 2015 Wiley Periodicals, Inc.