Prevalent oral human papillomavirus 16 infections in men persist longer than newly acquired infections, and the rate of persistence for incident infections increases with age, according to findings from the HPV Infection in Men (HIM) study.
Of 23 oral HPV-16–positive men aged 18 to 64 years who provided an oral gargle sample during at least two visits during the course of the ongoing multinational cohort study and who were followed for a median of 44.4 months, 13 acquired a new incident infection and 10 entered the study with a prevalent infection. Of the incident infections, 38.5% persisted for at least 1 month, and 10% persisted for at least 24 months; none persisted for more than 36 months (median duration, 7 months), but the rate of persistence for 12 months or longer increased significantly with age (100% of men aged 45 years or older had persistent infection vs. 50% of those aged 31-44 years, and 0% of those aged 18-30 years), Dr. Christine M. Pierce Campbell of the Moffitt Cancer Center and Research Institute, Tampa, Fla., and her colleagues reported online Jan. 9 in Cancer Prevention Research.
National Cancer Institute
Nearly 40% of oral HPV infections persisted for at least 48 months.
Of the prevalent infections, 90% persisted for at least 12 months, 80% persisted for at least 24 months, 57% persisted for at least 36 months, and 40% persisted for 48 months or longer, the investigators said, noting that persistence of prevalent infections also increased with age, but this finding was not statistically significant (Cancer Prev. Res. 2015 Jan. 9 [doi:10.1158/1940-6207.CAPR-14-0296]).
The findings may explain the high prevalence of oral HPV among older patients and could have implications for identifying men at high risk for developing HPV-related oropharyngeal cancer, they said, noting that evidence increasingly suggests that most oropharyngeal cancers among men are caused by HPV infection, and that most cases are diagnosed at an advanced clinical stage.
“Given that the overwhelming majority of prevalent oral HPV-16 infections detected here persisted beyond 1 year, and 40% persisted beyond 4 years, there is a clear need to evaluate whether long-term persistent oral HPV-16 infection can predict future oropharyngeal cancer risk. … mid-adult and older men appear to be at the highest risk of oral HPV infection and should be the focus of prevention interventions, they concluded.
The HIM study cohort was supported by grants from the National Cancer Institute and Merck Sharp & Dohme to individual authors. Dr. Campbell was supported, in part, by a postdoctoral fellowship and reported having no other disclosures.