Fig. 2.
Age-adjusted SEER incidence rates by subsite in the U.S., all races, both sexes from 1975-2013.19 OCSCC declining overall. The incidence of tongue cancer is inferred to account for the oral tongue and base of tongue, and its rise due to increasing rates of the latter, a distinct subsite of the oropharynx. Rates of OPSCC rising rapidly.