FRIDAY, Oct. 31 (HealthDay News) -- A simple mouth rinse can spot specific types of human papillomavirus, some of which cause genital warts and increase the risk of developing certain types of cancer, new research shows.

The study, published in the Nov. 1 issue of Clinical Cancer Research, reaffirms that people exposed to human papillomavirus (HPV-16), the variant that causes cervical cancer, are more likely to develop cancers of the head and neck.

The researchers followed 135 patients with head and neck cancer over five years, and found that the patients with HPV-16 positive tumors were far more likely to test positive for oral HPV-16 infections before, during, and after therapy.

Although past research has shown a strong association between cancers of the head and neck and HPV-16 infection, these researchers used genetic sequencing to confirm the link between HPV-16 infection and HPV-16 shed by tumors in patients with head and neck cancers. Patients with HPV-16 positive tumors were also more likely to test positive for all types of the virus.

"Most of the 50 percent of people who get an HPV infection at some point in their lives clear it with no problem," said study co-author Dr. Maura Gillison, an associate professor of oncology at Johns Hopkins. "The question is, how do we identify those who will have a problem from the infection with those who will not?"

Although the vaccine Gardasil has been shown to offer protection against HPV infection and thus reduce the incidence of cervical cancer, efforts to vaccinate young girls have been controversial. Some believe vaccinating young girls may encourage premarital sex or promote risky sexual behavior.

But the link between HPV infection and cancers of the head and neck has prompted many researchers to advocate vaccinating boys as well as girls. "In the future, vaccinating all young women between the ages of 9 and 26 would reduce oral cancer if HPV is indeed the cause," said Dr. Mark Werner, an obstetrician/gynecologist at William Beaumont Hospital in Royal Oak, Mich. "Maybe at some point, men or young boys will be vaccinated as well."

The study concluded that a noninvasive oral rinse may help researchers understand how different variants of the virus impact the development, outcome, and recurrence of different cancers.

"Can we use HPV oral detection for screening purposes to identify people who are at risk for this type of cancer?" asked Gillison. "The broader implications are that these can be applied to other studies."

More information

Find out more about HPV at the Centers for Disease Control and Prevention.