Which Clinicopathologic Factors Affect the Prognosis of Gingival Squamous Cell Carcinoma: A Population Analysis of 4,345 Cases.

PURPOSE: The purpose of this study was to present the characteristics and survival outcomes of primary gingival squamous cell carcinoma (SCC).

MATERIALS AND METHODS: We performed a retrospective cohort study using data from the Surveillance, Epidemiology, and End Results (SEER) tumor registry. Patients who received a diagnosis of primary gingival SCC were included in the analyses. The predictor variables were chosen from baseline demographic and tumor characteristics. The outcome of interest was survival, and Kaplan-Meier analyses were used to estimate rates of overall survival (OS) and disease-specific survival (DSS). Cox proportional hazards regression models were used for multivariate analyses.

RESULTS: In total, 4,345 patients (mean age, 70.2 years) with primary gingival SCCs were identified. There was a significantly positive association between T category and both nodal and distant metastases. The 2-, 5-, and 10-year OS rates were 63.1%, 46.5%, and 28.1%, respectively, whereas the DSS rates were 78.2%, 70.7%, and 62.2%, respectively. Multivariate Cox proportional hazards regression showed that the independent predictors of overall and disease-specific death were older age, intermediate and high histologic grade, tumor size, nodal disease, and the absence of surgery. T4 classification was significantly associated with only DSS. Race, gingival location (maxillary vs mandibular), verrucous histology, and the presence of distant metastases did not significantly affect survival when all other predictors were controlled for.

CONCLUSIONS: Older age at diagnosis, higher grade, increased tumor size, nodal disease, and the absence of surgery were each individually associated with lower OS and DSS. Because of low nodal disease rates, both T1N0M0 lesions and verrucous subtypes may be candidates for neck observation.