Dr. Maura Gillison, a Johns Hopkins oncologist, found that HPV causes some head and neck cancers, as well as cervical cancer. (Sun photo by Kim Hairston / April 11, 2008)
The sexually transmitted virus that causes cervical cancer in women has now been linked to an uptick of throat, tonsil and tongue cancers - in a younger and healthier group of patients than doctors have ever seen before.
These head and neck cancers were once the scourge of older men - mostly the result of lifetimes of heavy smoking and drinking. The treatments often left victims disfigured.
But with those cases on the decline, doctors are seeing a new group of victims. They're men in their 40s, and even 30s, whose cancer is brought on by the increasingly common human papillomavirus (HPV). It's an infection that more than half of Americans will encounter during their lifetimes. And researchers now believe that the increase in certain oral cancers can be traced to the spread of the virus through oral sex.
New studies suggest that HPV-related oral cancer cases are on pace to eventually surpass cases of cervical cancer in the United States, which strikes about 11,000 women each year. And many doctors do not realize that they should be on the lookout for oral cancer in younger patients.
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.
Two years after diagnosis, 95 percent of those with HPV-positive head and neck cancers were alive compared with 62 percent with HPV-negative cancers, research shows.
Even so, the treatment can have serious and long-lasting side effects. Some patients end up disfigured; others have difficulty speaking or swallowing. Gillison said those with HPV-positive tumors might be able to survive with less-damaging treatments.
Meanwhile, the HPV vaccine has been a financial boon for Merck & Co., the maker of Gardasil, the three-dose vaccine approved in the United States in 2006 for females ages 9 through 26. Doctors recommend vaccinating girls before they become sexually active and can be exposed to the virus.
Merck sold $1.5 billion worth of Gardasil last year around the world. GlaxoSmithKline is seeking U.S. approval for a competing drug called Cervarix.
Neither vaccine is approved for males. Both companies are studying whether it is safe in boys and whether it would prevent genital warts and rare cancers of the penis and anus. But neither has plans to study whether the vaccine would play any role in the prevention of HPV-linked oral cancers.
"Cervical cancer is really the focus," said Liad Diamond, a GlaxoSmithKline spokeswoman.
Experts said they think researchers will find the vaccine works on HPV throughout the body.
"The way the vaccine works, there's no reason to think it wouldn't protect against oropharanyx [tonsil, tongue and throat] cancer as it does cervical cancer," Sturgis said.
Dr. Aimee Kreimer, an epidemiologist at the National Cancer Institute in Bethesda, said that, theoretically, the vaccine should work on HPV anywhere in the body but such discussion is premature.
"Before recommending the vaccine to men, it's crucial to determine if the vaccination works to prevent infection in men," she said.
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Aimee Kreimer at NCI would think differently if she almost died from a stage four oral cancer as I did. My cancer was caused by HPV16, and the virus is the fastest growing segment of the oral cancer population according to the non profit Oral Cancer Foundation (www.oralcancer.org) All the vaccine companies need to do is prove that it prevents persistent HPV16 infection. That infection is the basis for oral cancers, anal cancers, and cancers of the penis to name a few. In 40 other countries around the world including Australia, the vaccine is given to both young boys and girls. Why they get that more people are going to die each year from oral cancers than cervical cancers... almost 3 times as many. As usual the pencil pushers (even if they have an MD after their name) that no longer practice and see patients, but inhabit our agencies, are dragging their feet on something that the science community already has said there is no down side to.
As to "cervical cancer being the focus" (GSK) it isn't because the are unaware of oral cancers, (ditto Merck) it is because the path of least resistance to market was to talk to the FDA about cervical, and not muddy the water with other ideas (oral anal etc.) Their decision to talk about preventing non deadly genital warts etc. when dealing with male vaccination is a marketing decision, not a science one. A position I find myopic at best, but which they think is the path of least resistance from the public. BH
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