Incidence rates of oral cavity and oropharyngeal cancers among men: A comparison of active-duty military and general populations

Objectives This study compared oral cavity and oropharyngeal cancer incidence rates and trends among men in the active-duty military and the general population of the USA. Methods Data were from the Department of Defenses' Automated Central Tumor Registry (ACTUR) and the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER-9) registries. Age-adjusted oral cavity and oropharyngeal cancer incidence rates among men aged 20-59 from 1990-2013 were compared between ACTUR and SEER populations. Results The age-adjusted oral cancer incidence rate was lower in ACTUR than SEER (IRR = 0.89, 95% confidence interval (CI), 0.81-0.98). Incidence was lower in ACTUR for oral cavity cancer (IRR = 0.75, 95% CI, 0.66-0.89) and remained lower when stratified by age and race. ACTUR oropharyngeal cancer rates were higher than SEER among Whites (IRR = 1.19, 95% CI, 1.01-1.39) and men aged 40-59 (IRR = 1.18, 95% CI, 1.00-1.39). Oropharyngeal cancer increased for both populations over time, whereas oral cavity cancer increased in ACTUR but decreased in SEER. Conclusion Rates were lower in ACTUR than SEER for oral cavity, but not for oropharyngeal cancer. Temporal oral cancer incidence patterns differed between the two populations. This study provides clues for more research on possible variations between these two populations and related factors.