Tumor volume as a prognostic factor on the median survival in locally advanced oral cancer treated with definitive chemoradiotherapy

Abstract

Background: Surgery has been the mainstay treatment for oral cancer. Patients who do not receive surgery are generally treated with concurrent chemoradiotherapy (CCRT). Many factors play a role in patients’ survival; tumor volume might be one of those factors. This study aims to determine the effect of the pre-treatment tumor volume on the survival of oral cancer. Methods: Retrospective study of patients with histological confirmed squamous cell carcinoma, stage III–IV oral cancer, who received definitive CCRT. Tumor volume from pre-treatment computed tomography (CT) scans were reviewed and analyzed. The optimal cut-off tumor volume was evaluated by receiver operating characteristic (ROC) curve analysis. Results: Among 67 patients, half of the primary tumor sites were oral tongue. The median total tumor volume (TTV) was 73.25 cm3, while the median survival was 12.5 months (95% confidence interval: 10.9-20.3). The optimal cut-off TTV ≥52.9 cm3 (P < 0.0001). The median survival of the patients, who had tumor volume <52.9 cm3 were 34.4 months, and for tumor volume ≥52.9 cm3 were 8.6 months (P < 0.0001). Multivariate analysis showed that TTV ≥52.9 cm3, and intensity-modulated radiotherapy (IMRT) or volumetric-modulated arc therapy (VMAT) technique had significantly influenced the overall survival. Conclusion: TTV had an influence on the overall survival of locally advanced oral cancer. In addition, TTV may be considered as a factor in selecting the appropriate treatment option for these patients.