The cases of oral cancer caused by a virus transmitted during oral sex appear to have increased drastically over the last 30 years, according to a study by US researchers.
The team led by Maura Gillison at Johns Hopkins University in Baltimore, Maryland, US, studied trends in oral cancers recorded by US National Cancer Institute registries, and suggested that this increasing trend can be related to changes in people's sexual behaviour.
The team said that the incidence of tongue, mouth and throat cancers due to the sexually transmitted human papilloma virus (HPV), which can also cause cervical cancer in women, increased by about a third from 1973 to 2004.
After looking at nearly 46,000 cases, the team identified 17,625 cancer that were potentially related to HPV and 28,144 that were potentially unrelated, based on factors such as anatomical sites strongly associated with HPV, including the tonsils and base of the tongue.
"What we do know is that the prevalence of HPV is high, particularly among young people and this shouldn't be a surprise given that, since the sexual revolution, people have been having more sexual partners," New Scientist magazine quoted Lesley Walker, director of cancer information at Cancer Research UK, as saying.
The increase was largest among young white males, signifying that this group is more likely to have oral sex at a younger age now than it was 20 years ago, explained Gillison's team.
Gillison called for a need to consider giving boys the HPV vaccine, to protect them from the disease.
A Merck vaccine is presently licensed for use in young women and girls to protect them against the most common cervical cancer-causing strains of HPV.
"We need to start having a discussion about those cancers other than cervical cancer that may be affected in a positive way by the vaccine," Gillison said.
The study is published in the Journal of Clinical Oncology.