Background: Despite significant reductions in tobacco use in the US, oral tongue cancer incidence has reportedly increased in recent years, particularly in young white women. We conducted age-period-cohort analyses to identify birth cohorts that have experienced increased oral tongue cancer incidence, and compared these with trends for oropharyngeal cancer, a cancer caused by human papillomavirus (HPV) that has also recently increased.
Methods: We utilized cancer incidence data (1973-2012) from 18 registries maintained by the NCI SEER Program. Incidence trends were evaluated using log-linear joinpoint regression and age-period-cohort modeling was utilized to simultaneously evaluate effects of age, calendar year, and birth year on incidence trends.
Results: Incidence of oral tongue cancer increased significantly among white women during 1973-2012 (0.6% annual increase, p<0.001) and white men during 2008-2012 (5.1% annual increase, p=0.004). The increase was most apparent among younger white individuals (<50years; annual increase of 0.7% for men [p=0.02] and 1.7% for women [p<0.001] during 1973-2012). Furthermore, the magnitude of the increase during 1973-2012 was similar between young white men and women (2.3 vs. 1.8 cases per million, respectively). Incidence trends for oropharyngeal cancer were similar to trends for oral tongue cancer and similar birth cohorts (born after the 1940s) experienced rising incidence of these cancers (p-value: white men=0.12, white women=0.42), although the magnitude of increase was greater for oropharyngeal cancer.
Conclusions: The incidence of oral tongue and oropharyngeal cancer has significantly increased among young white men and women within the same birth cohorts in the US.
Keywords: Age-period-cohort analysis; Incidence; Oral tongue cancer; Temporal trends.
Published by Elsevier Ltd.