Clinicopathologic Evaluation of Prognostic Factors for Squamous Cell Carcinoma of the Buccal Mucosa

Abstract

The purpose of this research was to evaluate the prognostic significance of clinicopathologic variables on the survival rate for squamous cell carcinoma of the buccal mucosa (BMSCC). We analyzed the outcomes of surgical therapy for this aggressive cancer and compared these results with those in the literature. We reviewed the medical charts of 172 patients treated in our institution between 1990 and 2005. There were 22 patients excluded from our studies: 20 patients with advanced tumors who received no treatment or palliative treatment, and 2 patients who had received preoperative radiotherapy (RT). The remaining 150 patients were treated with surgeries and among them, 56 patients had undergone postoperative RT. The influence of clinicopathologic factors on the survival rate was analyzed with the Kaplan-Meier method and log-rank test. Multivariate analysis was assessed with Cox's regression model. There were 148 males and 2 females, with a mean age of 53.5 years. The prevalence rate of habitual betel quid chewing documented in charts among 113 patients was 75%. The 5-year overall survival rate and disease-specific survival rate for all patients were 64% and 69%, respectively. For patients with stages I, II, III, and IV disease, the 5-year disease-specific survival rates were 90%, 77%, 52%, and 47%, respectively (p<0.001). According to the multivariate analysis, the pathologic staging and histologic grading of the tumor were independently the important prognostic factors affecting survival rate. There were 80 patients who developed locoregional recurrence in lymph nodes in the follow-up diagnoses. Distant metastases occurred in 14 patients, with 11 of them also having locoregional recurrence. The distant metastases were found in the lungs (8/14), T-spine (3/14), liver (2/14) and brain (1/14). Pathologic stage and histologic grade are the most important prognostic factors.