Survival pattern and prognostic factors of oral cancer in Sri Lanka

Abstract

BACKGROUND: Oral cancer is the commonest cancer among men and the second commonest overall in Sri Lanka. Obj ective: To determine the survival pattern and prognostic factors of oral cancer. DESIGN, SETTING AND METHODS: A cohort of patients who were treated for oral cancer at the National Cancer Institute, Maharagama (NCIM) from 1991 to 2000 was traced to their homes to obtain socio-demographic and survival information. Disease and treatment related information were extracted from patient records. The survival of untraced patients was taken up to the last day of contact and censored. RESULTS: Of the 750 patients [mean age-60.6 (SD=11.2) years; males=77.9%] studied, 548 (73.1%) were traced. 465 were dead, and 83 patients were alive on lsl January 2006. Overall 5-year survival rate was 24%. Patients diagnosed in early stages and who underwent surgery had a significantly higher median survival. Overall survival was significantly better in patients who were diagnosed early, patients who had surgery and in patients diagnosed between 1991-1995. The survival probabilities at selected time points were significantly different between patients diagnosed early vs. late, who received surgery vs. not, and patients with cancers of the oral cavity vs. cancers of the oro-pharynx. Age (hazards ratio (HR)=1.01), stage at diagnosis (HR=2.34), waiting time for treatment (HR=0,99) and year of diagnosis (HR=1.21) were significantly associated with survival in Cox's regression analysis. CONCLUSIONS: Established prognostic factors like age, stage at diagnosis and waiting time for treatment are important in Sri Lanka. While the year of diagnosis needs further evaluation, early detection and prompt treatment will be very important for improving survival.