Global incidence trends in head and neck cancer for HPV-related and -unrelated subsites: A systematic review of population-based studies.

In head and neck cancer (HNC), some subsites are associated with human papillomavirus (HPV) infection, whereas others are unrelated. Although studies have demonstrated the heterogeneity of HPV prevalence worldwide, its impacts on incidence trends in HNC are unknown. This systematic review examined the incidence trends for HPV-related HNC subsites, exploring patterns by geographic region, age group, sex, and race/ethnicity. We searched for publications on PubMed, Embase, and Scopus. Eligible articles included population-based studies that analyzed incidence trends for subsites classified as a proxy for HPV infection in HNC (hereafter referred to as HPV-related subsites). We retrieved 3,948 non-duplicate records, of which 31 were eligible articles, representing 18 countries and spanning almost fifty years. Overall, the incidence of HPV-related HNC subsites rose, while most of the HPV-unrelated subsites declined or remained stable. For HPV-related HNC subsites, incidence trends increased regardless of age group, highlighting a distinct global pattern between sexes. Also, similar peaks in increased risk were observed in recent cohorts from both Australia and the United States. There is a dramatic shift in the global trends of HNCs, characterized by the emerging burden in HNC for HPV-related subsites.