Survival time and prognostic factors of oral cancer in Ubon Ratchathani Cancer Center

Abstract

Objective: To characterize the survival time and prognostic factors of oral cancer in Ubon Ratchathani, Thailand. Material and Method: A total of 519 patients with oral cancer in the Ubon Ratchathani Cancer Center were recruited retrospectively over 5 years, from January 1, 2002 to December 31, 2006. The survival status of the patients was followed until December 31, 2007. Survival times were estimated and compared using the product-limit (Kaplan-Meier) method. Cox Proportional Hazards models were used to examine prognostic factors. Results: At the end of the study, 384 patients (74.0%) had died. The mean age of the patients at diagnosis was 64.15 years, with a male to female ratio of 1:1.56. Location of cancer were found at tongue (25.2%), buccal mucosa (22.4%), gum (21.1%), lip (17.5%) and others (13.7%). Squamous cell carcinoma was the most common cell type (92.7%). The median survival time was 337 days and the survival probability at 1, 3 and 5-years were 46.7%, 26.4% and 18.2%, respectively. In multivariable analysis, patients at the greatest risk of death were those having cancer of the tongue (HR 1.93, 1.20, 3.11) compared to cancer of the lip and being in stage IV at diagnosis (HR 3.57, 95% CI = 1.79, 7.13) as compared to stage I. Conclusion: Patients with advanced tumors had the worst prognosis, underscoring the importance of improved early detection for early treatment.