Not long ago, the human papillomavirus (HPV) was identified as a cause of cervical cancer in women. This discovery led to the widespread immunization of young girls against HPV and optimism that this would drastically reduce the incidence of cervical cancer in the future.

There is, however, another devastating form of cancer that few people realize is also linked to HPV — head and neck cancer.

"Right now I think the public and most physicians have no idea that HPV relates to head and neck cancer," said Dell Yarbrough, M.D., Vanderbilt-Ingram Cancer Center surgical oncologist. "In cancers of the oropharynx, which includes the tonsils, the base of the tongue, and part of the throat, about half of those tumors are HPV-positive. In the oral cavity, between 10 and 15 percent of tumors test positive for HPV, although here at Vanderbilt-Ingram we're seeing up to 20 percent."

HPV is one of the most common sexually transmitted diseases worldwide. The Centers for Disease Control and Prevention (CDC) estimates that there are nearly 6.2 million new genital HPV cases in the United States yearly. Now researchers have documented that some increasingly common types of head and neck cancer are related to HPV, especially cancer in the tonsils. The spike in tonsillar cancer coincides with two social trends -- earlier sexual activity and an increase in oral sex.

"Head and neck cancer used to be a disease of people in their 50s and 60s who smoked and drank heavily," said Yarbrough. "The younger population was at very low risk until recently. But now we're seeing an increased incidence in young nonsmokers and nondrinkers. Everybody assumes oral sex is a possible link to HPV infection, but if your partner had oral sex and is a carrier of the virus, that could be another link. No one is sure."

Symptoms of head and neck cancer include hoarseness, pain in the nose, mouth or throat, a lump or bump in the neck, ulcers in the mouth, loose teeth or changes in swallowing or speech.

"Head and neck cancer is devastating," Yarbrough said. "The overall cure rate of all but the earliest stages of head and neck squamous cell carcinoma is hovering around 60 percent and the percentage hasn't changed in decades. So that means if 10 patients come in to see us, only six are going to survive."

There are more than 100 subtypes of HPV. Types 16 and 18 have been implicated in cervical cancer.

Those are the same subtypes often found in HPV-positive head and neck cancers. Gardasil — a new vaccine approved last year — is effective against those HPV subtypes but the vaccine is only approved for use in girls and women ages 9 to 26.

To reduce the risk of HPV leading to head and neck cancer, Yarbrough recommends considering vaccinating young men as well as women.