Purpose: The purpose of the study was to determine the prognostic significance of the ratio between metastatic and examined lymph nodes to the survival rate of patients with squamous cell carcinoma of the head and neck.
Materials and methods: The study included 142 patients in whom metastatic lymph nodes were observed in neck dissection specimens. The number of metastatic lymph nodes and the ratio of metastatic lymph nodes (RMLN) were compared as prognostic factors affecting overall survival (OS) and disease-free survival (DFS) rates. Survival curves were made using Kaplan-Meier analysis and were assessed by the log-rank test and Cox regression method.
Results: The median number of metastatic lymph nodes and RMLN for the entire study population were 2 and 4%, respectively. The OS and DFS rates were analyzed in the groups according to such stratification. The result of analysis of OS and DFS showed a statistically significant difference between patients with RMLN of at least 4% and those with RMLN less than 4% (hazard ratio, 3.4 and 2.7; P = .015 and P = .001, respectively).
Conclusions: The ratio of metastatic lymph nodes has a significant impact on the survival period.
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