People with oral HPV infection have 22 times the risk for oropharyngeal cancer

People who have human papillomavirus (HPV)-16 in the mouth are 22 times more likely to develop oropharyngeal cancer compared with those without HPV-16, according to a study published online January 21, 2016, in JAMA Oncology. It’s the first study to conclusively find that HPV-16’s presence in the oral cavity precedes the development of oropharyngeal cancers.

Other studies have indicated that detection of HPV in the oral cavity is related to sexual contact. HPV infection (overwhelmingly HPV-16) is a known cause of head and neck squamous cell carcinoma (HNSCC), predominantly oropharyngeal cancer. But what has not been known is the risk of HNSCC from oral HPV infection.

In this study, researchers at Albert Einstein College of Medicine in Bronx, NY, included nearly 97,000 people from two large national prospective studies. Participants were cancer-free and had provided mouthwash samples.

After an average of nearly four years of follow-up, researchers identified 132 cases of head and neck cancer (103 men and 29 women; average age 66.5 at baseline). The study also included a comparison group of 396 healthy control subjects—3 controls for each case of HNSCC.

Researchers analyzed mouthwash samples from HNSCC cases and from controls for the presence of several types of oral HPVs. They found that people with HPV-16 in their mouthwash samples were 22 times more likely to develop oropharyngeal cancer than participants with no HPV-16.

“The use of easily collected oral mouthwash samples can provide a prospective marker for risk of HNSCC and oropharyngeal SCC,” the authors concluded.

The researchers also found for the first time that other types of oral HPVs—beta- and gamma-HPVs, which are usually detected in the skin—were also associated with the development of head and neck cancers. This finding indicates that HPVs have a broader role in the etiology of HNSCC cancers than had been known, the researchers noted.