According to a new study published in Cancer Prevention Research, one type of oral human papillomavirus infection (HPV16) appears to last one year or longer in men older than 45.
Oral infection with HPV16 is most frequently associated with HPV-driven head and neck (oropharyngeal) cancers.
HPV-positive oropharyngeal cancers in men has significantly increased over the last 20 years. In fact, annual cases of HPV-positive oropharyngeal cancers have surpassed cervical cancer cases.
“We don’t know how long oral HPV infection must persist to increase risk for head and neck cancer, but we assume it would be similar to cervical infection, where it is generally believed that infections persisting beyond two years greatly increase the risk of developing cervical cancer,” Christine M. Pierce Campbell, PhD, MPH, from the Department of Cancer Epidemiology and Center for Infection Research in Cancer at the Moffitt Cancer Center told the ASCO Post.
Whereas genital HPV infections usually clear up in two years or less, this study's findings suggest that oral infections may be more persistent.
The research team evaluated 1,626 men who were part of the HPV Infection in Men study. At enrollment, they collected oral gargle samples from the participants and then every six months for four years checking for the presence of oral HPV16 infection.
Over the duration of the study, HPV16 was discovered in two or more samples from 23 men. For 10 men, it was present in the enrollment sample.
In the group that had HPV16 at the study’s start, nine had infections that lasted a year or more. Researchers also found that eight of these infections lasted two years or more. Two lasted four years or longer.
The proportion of incident infections (those detected during the course of the study) persisting for one year or longer increased with age.
All incident infections among men older than 45 persisted for one year or longer. Fifty percent of those infections among men ages 31-44 persisted for one year or longer. And none of the incident infections detected among men ages 18-31 persisted for a year.