Oral HPV Detection

Human papillomavirus (HPV) is a family of more than 200 viruses passed by skin and mucosal contact. A few of them infect the lining of the mouth and throat, and one in particular, HPV 16, now causes most cancers of the oropharynx (the tonsils and the base of the tongue) in the United States, more than tobacco does. This test looks for HPV DNA in an oral rinse: you swish and gargle a saline solution, which collects cells from the mouth and throat, and the lab amplifies the viral DNA by PCR.

The report leads with one call. Negative means no HPV DNA was found in the sample that day, which is what about 93 percent of American adults would get; a negative does not rule out a very low level of virus or an area the rinse did not reach, and the other causes of mouth and throat cancer, tobacco and alcohol above all, still apply. Positive means HPV DNA was present, and the lab then types it: the 50 genotypes on the panel, sorted into the high-risk types that can cause cancer (16 and 18 first), the low-risk types behind warts, and types of unknown risk.

A positive is an infection, not a cancer, and most oral HPV infections clear on their own within a year or two. What matters is the type and whether it persists: a high-risk type still present on a repeat rinse 6 to 12 months later is the finding that marks someone out for closer attention, which means a careful look at the mouth and throat by a dentist, a physician or an ear, nose and throat specialist, and a low threshold for examining any lump in the neck, a persistent sore throat or a change in voice or swallowing. There is no medication that clears the virus itself; not smoking helps it clear and lowers the cancer risk on its own.

The HPV vaccine protects against new infections with the types that cause most cancers, 16 and 18 included, but does not treat an infection already there. It is routine through age 26 and a shared decision between 27 and 45.