Objectives：Lymph node density (LND) has been reported to be a significant predictor of survival in oral squamous cell carcinoma and other carcinomas with positive lymph nodes. We investigated whether LND is correlated with overall survival in major salivary gland carcinoma.
Methods: Seventy-eight patients newly diagnosed to have major salivary gland carcinoma underwent both primary tumor resection and neck dissection without preoperative treatment. Of these 78 patients, 32 patients with pathologically positive lymph nodes were enrolled in this study. The LND was calculated as the ratio of the number of positive lymph nodes to the number of total lymph nodes. The survival rate was analyzed by the Kaplan-Meier method. A univariate survival analysis was performed using the log-rank test, and a multivariate survival analysis was performed using the Cox proportional hazards model.
Results: A LND ≧ 0.38 was significantly correlated with a shorter overall survival in univariate analysis (p< 0.02). In a multivariate survival analysis with adjustment for the anatomical location (parotid gland/others), LND ≧ 0.38 was associated a significantly shorter overall survival.
Conclusion: These results suggest that the LND is able to provide a prognostic factor for major salivary gland carcinoma.