Cancers of the tonsil and base of the tongue have increased in past decades among middle-aged and younger Americans, and experts believe it’s triggered by the human papillomavirus – which can be transmitted through oral sex, Health Day News reported.

“It seems like a pretty good link that more sexual activity, particularly oral sex, is associated with increased HPV infection,” said Dr. Greg Hartig, professor of otolaryngology-head and neck surgery at the University of Wisconsin School of Medicine and Public Health in Madison.

According to another doctor, Dr. William Lydiatt, professor of head and neck surgical oncology at the University of Nebraska Medical Center in Omaha, the incidence of other neck cancers are decreasing because fewer people are smoking and drinking, which are traditionally risk factors.

“It’s gotten to the point now where 60 to 70 percent of all tonsil cancers in the U.S. are HPV-related,” Lydiatt said.

A study appearing in a 2007 issue of the New England Journal of Medicine found that those people who had six or more oral sex partners in their life had a risk 3.4 times higher for oropharyngeal cancer.

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