Squamous cell carcinoma of the oral tongue: an analysis of prognostic factors

Abstract

Aim: To identify the prognostic significance of different factors in patients with squamous cell carcinoma of the tongue. Patients and methods: Seventy-seven patients with carcinoma of the tongue were treated radically at the King Faisal Specialist Hospital and Research Centre between 1980 and 1989. Twenty patients (26%) were treated by resection alone, 11 (14%) with radiotherapy alone, and 46 (60%) with combined resection and radiotherapy.Results : Forty-seven patients (61%) had T_1–2, 28 (36%) T_3–4, and two T_xtumours. The regional nodes were clear in 53 (69%) and contained metastases in 24 patients (31%). Thirty patients (39%) developed recurrences, which were local in 9, regional in 14, locoregional in 5, and locoregional with metastatic disease in 2. The five and 10-year overall actuarial survival for all patients were 65% and 53%, respectively, and the corresponding relapse-free survival 56% and 50%. Univariate and multivariate analyses were done of seven variables – age (<40 compared with ≥40 years), sex, chewing tobacco use, smoking, TNM stage, surgical margins (clear or invaded), and treatment (resection, radiotherapy, or the combination). On univariate analysis chewing tobacco (P =0.04), smoking (P =0.01), invaded resection margins (P =0.04), involved regional lymph nodes (P =0.009), T4 tumours, and patients treated with radiotherapy alone (P =0.001) were associated with poor overall survival. Factors associated with shorter relapse-free survival were age >40 (P =0.03), chewing tobacco (P =0.04), invaded resection margins (P =0.01), and smoking (P =0.01). On multivariate analysis, invaded resection margins and smoking (P =0.04)(P =0.02) were associated with shorter overall survival and relapse-free survival (P =0.03 and (P =0.01), while chewing tobacco independently influenced relapse-free survival only (P =0.03). Conclusion: Invaded resection margins and smoking were the only independent prognostic factors that affected both overall and relapse-free survival. Those who chewed tobacco were at high risk of locoregional failure.