Cancer-causing virus found more often
But there may be hints in the 2007 New England Journal of Medicine study. While more people may not engage in oral sex, they may have more partners - and at earlier ages. The journal's authors found that people who had at least six different oral sex partners were at higher risk of developing HPV-related head and neck cancers.
"The widespread oral sexual practices among adolescents may be a contributing factor in this increase," the study's authors wrote.
It's also not yet known how the HPV vaccine might affect the rates of head and neck cancers. The first HPV vaccine, Gardasil, was approved in 2006 to thwart cervical cancer, and has been recommended for young women before they become sexually active.
Some health leaders have suggested that men should be vaccinated, too.
Brizel said that approach may be unnecessary if enough women are inoculated against the virus.
"From a public health standpoint, there are lots of other things to vaccinate against - polio, flu, etc.," he said.
Brizel said HPV-related head and neck cancers respond better to treatment than other such cancers. He said patients who don't have a recurrence of cancer after two or three years are generally considered cured.