Survival outcomes of First Nations patients with oral cavity squamous cell carcinoma (Poliquin 2014)

BACKGROUND: Oral cavity squamous cell carcinoma (OCSCC) is the most common head and neck cancer, affecting approximately 2000 Canadians yearly. Analysis of Canadian Cancer Registry data has shown that the incidence of oral cavity cancer is decreasing and survival outcomes are improving. There are significant health disparities in First Nations (FN) people in Canada. The incidence of cancer in FN groups is significantly lower when compared to the general population, but the cancer-related morbidity and mortality is significantly higher. There is no Canadian literature currently for OCSCC, or any other head and neck cancer, that compares survival outcomes of FN to the overall population. Therefore, the objective of this study is to determine whether there is a difference in epidemiology and survival outcomes between FN and non-FN patients with OCSCC. METHODS: This is a retrospective study of a population-based, prospectively-collected database from Alberta Cancer Registry (ACR). Patients with OCSCC, diagnosed and treated in Alberta between 1998 and 2009 were included. ACR data collected included patient gender, age at diagnosis, tobacco and alcohol use, FN status, TNM staging, performance status, date of death, cause of death, and follow-up. FN status was identified through the Alberta Health and Wellness registry and through postal code correlation for those who live on reserves. RESULTS: A total of 583 patients with OCSCC were included in this study. Of these, 19 were identified as being FN, leaving 564 non-FN patients. When comparing the FN and non-FN groups, there is no significant difference in baseline demographics. Estimated yearly incidences for OCSCC in the Alberta population (all ages) and FN patients are 1.74/100,000 and 1.32/100,000 respectively (p = 0.23). Significant differences are seen in overall survival (OS) (5-year OS 58.1% for non-FN and 33.7% for FN) and for disease-specific survival (DSS) (5-year DSS 67.8% for non-FN and 44.5% for FN). Multivariate analysis confirmed FN patients have a significant increase risk of death in OS and DSS, with hazard ratios of 4.20 (p = 0.01) and 4.57 (p = 0.02), respectively. CONCLUSIONS: The overall survival and disease specific survival are significantly lower in FN patients compared to non-FN patients with OCSCC.