"The public is unaware of this," said Dr. Erich Sturgis, a head and neck surgeon at The University of Texas M.D. Anderson Cancer Center who has studied HPV. "It's just starting to filter out."
It doesn't even occur to some primary-care doctors that their patients younger than 60 might have developed oral cancer, but researchers say a lingering sore throat or a lump in the neck could be symptoms of the disease and should be checked out.
These cancers remain relatively rare, despite a 5 percent increase in cases each year since 2000. Estimates put cases of HPV-associated head and neck cancers at 6,000 per year - and cervical cancer cases at fewer than 11,000.
Debbie Roffman, a human sexuality educator at Park School and author of Sex and Sensibility: The Thinking Parent's Guide to Talking About Sex, discusses risky behaviors with her students, some of whom are in middle school. But sometimes it's hard to get the message through, especially when students are sure those behaviors won't hurt them.
"They're not going to be as focused on invisible things like germs and long-developing things like cancer that are way off in the future," she said.
Gillison said everyone involved - from pre-teens to primary-care doctors - must change their perception of who is at risk. Doctors taking medical histories typically ask about smoking- and alcohol-related behaviors, but she said they should ask about sexual history, too.
"Now most of us are at risk, because humans are sexual beings," she said.
The rise of HPV-related head and neck cancers is not just a U.S. phenomenon. Swedish researchers who re-examined samples from the 1970s have found that 28 percent of oral tumors were HPV-positive. In tumors from 2000 to 2002, HPV-positive samples jumped to 68 percent.
In a study by Gillison and others last year, 72 percent of certain oral cancers were HPV-positive.
HPV is typically spread through sexual contact. While many women will have HPV at some point in their lives, they frequently have no symptoms and the virus usually goes away on its own. Sometimes, HPV lingers and becomes cancer - a process that can take decades.
Doctors are familiar with this progression because pre-cancerous lesions are often caught during Pap tests. But they don't know much about how progression occurs in the throat and mouth.
Gillison and her colleagues say HPV-related oral cancers appear to be distinct from those not associated with the sexually transmitted infection and appear to respond differently to treatment.
