It's common knowledge that HPV — or human papillomavirus — is linked with cervical cancer, thanks to the controversy over the vaccine. But far fewer people know that this same sexually transmitted viral strain is connected to oral cancers, according to a new study, recently published in the Journal of the American Medical Association.
For years, clinicians thought these kinds of cancer — affecting the tongue and tonsil areas — were almost exclusively caused by tobacco use, since they mostly struck heavy smokers and drinkers. But according to Dr. Maura Gillison, an oncologist and researcher at Ohio State University, it's not cigarettes that are the culprit, but oral sex. The good news: Most people with oral HPV will never develop cancer.
Dr. Ezra Cohen, a specialist in head, neck, thyroid and salivary gland cancers at the University of Chicago, helped explain what it all means:
Q. In general, mouth cancers are increasing?
A. Oropharynx cancer is on the rise dramatically. It's gone up 3 percent a year for the last three decades and will surpass all other sites for head and neck cancers.
Q. And HPV-positive oral cancers?
A. They will surpass cervical cancers within the next three years. It's only relatively recently that we've come to realize the scope of HPV-related cancers.
Q. What have we learned from this study?
A. Quite a lot, actually. It told us about prevalence — that about 7 percent of adults in the U.S. are infected with oral HPV... and that this cancer is a sexually transmitted disease, requiring oral sexual contact. It also explained why we're seeing an epidemic of oral cancers and why it's more common in men — who are three times as likely to get HPV-related cancer — and those who have had many sexual partners.
Q. So if oral sex is connected to oral cancers, why are we just seeing an increase now?
A. Because sexual encounters have changed over the last 30 or so years. The age of the first oral sexual encounter has dropped by about a decade and half since the 1980s and the number of people engaging in the practice has increased too. ... We think mostly due to the AIDS epidemic and people trying to protect themselves. So, as oral sex became more common, so did oral cancers. The cancers take 20 to 30 years to develop, so sexual practices during your teens and 20s may put you at risk for cancer in your 50s. So those engaging in risky behaviors now may be setting the stage for later.
Q. There are many types of HPV, but only one type is linked to oropharynx cancer?
A. That's essentially right. HPV-16 is strongly linked with oral cancer. That form was only found in about 1 percent of the people and, of those, less than 15,000 actually develop cancer.
Q. Do we know if the HPV vaccine that is supposed to protect against cervical cancer is also effective against HPV-related oral cancer?
A. Right now we do not know. There are some key immunologic differences between how our bodies respond to infections in the cervic and oral cavity. Nonetheless, we think the vaccines will be protective and they are approved for both females and males. Remember, these are preventative vaccines, so one has to be immunized before exposure to the virus — that is, before sexual contact.
Q. Is there any kind of screening for early detection?
A. No. We are working on that, but right now there is no "pap smear" for HPV-related oropharynx cancer.
Q. What are the symptoms for these oral cancers?
A. Sore throat, difficulty swallowing, a change in your voice or speech. If you have a lump in your neck that doesn't go away in a week or two — those are all symptoms that you'd want to get evaluated by your doctor.
Q. As someone who has studied all oropharynx cancers for 12 years, what would you like people to know? Most Americans think if they've never smoked, it's one disease they don't have to worry about. A false sense of security?
A. Most patients with HPV-related oropharynx cancers never smoked. Yes, smoking increases your risk for head and neck cancer and everyone should talk to their doctor about stopping. But even if you have never smoked, you can still get oropharynx cancer, so if you have some worrisome symptoms, get them evaluated.