Incidence trends for human papillomavirus-related and -unrelated oral squamous cell carcinomas in the United States

Purpose To investigate the impact of human papillomavirus ( HPV) on the epidemiology of oral squamous cell carcinomas ( OSCCs) in the United States, we assessed differences in patient characteristics, incidence, and survival between potentially HPV-related and HPV-unrelated OSCC sites. Patients and Methods Data from nine Surveillance, Epidemiology, and End Results program registries ( 1973 to 2004) were used to classify OSCCs by anatomic site as potentially HPV-related ( n = 17,625) or HPV-unrelated ( n = 28,144). Joinpoint regression and age-period-cohort models were used to assess incidence trends. Life-table analyses were used to compare 2-year overall survival for HPV-related and HPV-unrelated OSCCs. Results HPV-related OSCCs were diagnosed at younger ages than HPV-unrelated OSCCs ( mean ages at diagnosis, 61.0 and 63.8 years, respectively; P <.001). Incidence increased significantly for HPV-related OSCC from 1973 to 2004 ( annual percentage change [ APC] = 0.80; P <.001), particularly among white men and at younger ages. By contrast, incidence for HPV-unrelated OSCC was stable through 1982 ( APC = 0.82; P =.186) and declined significantly during 1983 to 2004 ( APC = -1.85; P <.001). When treated with radiation, improvements in 2-year survival across calendar periods were more pronounced for HPV-related OSCCs ( absolute increase in survival from 1973 through 1982 to 1993 through 2004 for localized, regional, and distant stages = 9.9%, 23.1%, and 18.6%, respectively) than HPV-unrelated OSCCs ( 5.6%, 3.1%, and 9.9%, respectively). During 1993 to 2004, for all stages treated with radiation, patients with HPV-related OSCCs had significantly higher survival rates than those with HPV-unrelated OSCCs. Conclusion The proportion of OSCCs that are potentially HPV-related increased in the United States from 1973 to 2004, perhaps as a result of changing sexual behaviors. Recent improvements in survival with radiotherapy may be due in part to a shift in the etiology of OSCCs.