US News

DEEP THROAT

A rare cancer in the back of the throat is “strongly associated” with a virus transmitted during oral sex, researchers believe.

The research also suggests that unprotected oral sex is a major reason people are contracting throat cancer – not just smoking and excessive alcohol consumption, as previously believed.

“It’s the human papillomavirus that drives the cancer,” said Maura Gillison, assistant professor of oncology and epidemiology at Johns Hopkins University in Baltimore, Md., and lead author of the study.

She said the more oral-sex partners a person has, the greater the risk of contracting oral cancers (located in the tonsils, back of the tongue and throat). The good news is that the risk remains low over all.

“People should be reassured that oropharyngeal cancer is relatively uncommon, and the overwhelming majority of people with an oral HPV infection probably will not get throat cancer,” Dr. Gillison said.

A new vaccine protects against infection by several strains of HPV, including the one associated with oral cancer, HPV-16. However, Dr. Gillison said it has not been specifically tested for its effectiveness against oral cancer.

A study of 100 women diagnosed with cancers at the back of the throat, published in the New England Journal of Medicine, has linked human papillomavirus (HPV) with throat cancer. It concluded oral HPV infection was associated with oropharyngeal cancer among people with or without the other risk factors of tobacco and alcohol use.

Infection with sexually transmitted HPV is a cause of virtually all cervical cancers.

The researchers from Johns Hopkins University also found a high lifetime number of oral sex or vaginal sex partners, engagement in casual sex, early age at first sexual encounter and infrequent use of condoms were associated with a strain of HPV-positive oropharyngeal cancer. They conclude that the “widespread oral sexual practices among adolescents” may have contributed to a rise of this type of cancer in the US, and provide a rationale for HPV vaccination in both boys and girls.

Study participants who reported having oral sex – be it fellatio or cunnilingus – with six or more partners were at greatest risk of contracting oropharyngeal cancer.

There is no screening test for oral cancer; it is usually detected when there is a sore in the mouth that does not heal.