Squamous cell carcinoma of the buccal mucosa: analysis of prognostic factors.

Although the TNM system is the accepted standard for head and neck tumor classification, there are often discrepancies between tumor size and survival. This retrospective analysis of 89 patients with squamous cell carcinoma of the buccal mucosa was carried out to evaluate tumor thickness and depth of invasion as prognostic variables and to compare them to the standard parameters. Recurrence rates increased with tumor size, clinical stage, thickness, and depth of invasion. In univariate analysis, sex, clinical stage, thickness, and depth of invasion were significantly related to survival (p less than 0.10). Multivariate analysis revealed that only thickness was an independent variable (p less than 0.0001). Patients with tumors less than 6 mm in thickness had a significantly better survival rate compared with those patients with tumors greater than 6 mm in thickness, regardless of the tumor stage. Measurement of tumor thickness should be included in estimating prognosis, planning therapy, and comparing results in patients with squamous cell carcinoma of the buccal mucosa.