Incidence and Survival of Oral Cavity and Oropharyngeal Cancer in the United States From 1975 to 2018

Oral cavity and oropharyngeal cancer (OC-OPC) is one of the most common cancers in the world. A comprehensive investigation of the temporal changes in incidence, overall survival (OS), and associated factors of this disease may facilitate the formulation and modification of public health control measures.This is a retrospective cohort study based on the Surveillance, Epidemiology, and End Results (SEER) database (1975 to 2018). Average annual percentage change (APC) in incidence was calculated by linear regression. Associations of incidence and OS with time and covariates (age, race, gender, site, grade, income, and residence) were analyzed. The Kaplan-Meier log-rank test was used for analysis of OS. Hazard ratio (HR) and 95% confidence intervals (CIs) were calculated by Cox regression models.This study included 92,685 patients diagnosed with OC-OPC in Surveillance, Epidemiology, and End Results 9 database. An overall decrease was discovered in the incidence, especially among the Black population (APC, -15.2; 95% CI, -17.5 to -13.0; P < .01), and among those at 60+ years of age (APC, -12.8; 95% CI, -18.6 to -7.0; P < .01). Notably, the incidence among the rural population (APC, 7.1; 95% CI, 4.4 to 9.8; P < .01) increased. Residence and gender had the greatest effect on changes in incidence. Univariate analysis showed that the prognosis was worse in patients diagnosed between 1975 and 2000, patients from the Black population (HR, 1.87; 95% CI, 1.81 to 1.93; P < .01), patients at 60+ years of age (HR, 1.64; 95% CI, 1.61 to 1.68; P < .01), and patients with OPC. Interestingly, multivariate analysis showed no significant difference between OPC and OC, and the results of other subgroups were similar to univariate analysis.The results of this study indicate that more attention should be paid to facilitating OC-OPC prevention in rural population, as well as improving management of this disease in Black and elderly populations, and among patients with higher grade of disease and lower income.