Actor Spotlights HPV Link to Throat Cancer

Actor Michael Douglas startled many this week by appearing to say that his throat cancer was caused by oral sex. The Guardian, a British newspaper, published the interview with Douglas June 3. When asked about his cancer, he said, "without wanting to get too specific, this particular cancer is caused by HPV (human papillomavirus), which actually comes from cunnilingus." Later, his spokesman said Douglas only meant that oral sex was one of the causes of his cancer. Douglas also has a history of smoking and heavy drinking. In the past, he has attributed his throat cancer to those causes. But HPV also can cause throat cancer. Those caused by smoking and alcohol have declined in the last 20 years. Those caused by HPV have increased. The virus is now the leading cause or oropharyngeal cancer. These cancers occur in the part of the throat at the back of the mouth, the base of the tongue and the tonsils. HPV also causes genital warts and most cases of cervical cancer. The Associated Press wrote about the issue.

By Howard LeWine, M.D.
Harvard Medical School

What Is the Doctor's Reaction?

Actress Angelina Jolie recently went public with her double mastectomy to prevent breast cancer. Governor Chris Christie told us his reasons for gastric bypass surgery. And now actor Michael Douglas has brought increased awareness about the No. 1 cause of mouth and throat (oropharyngeal) cancer. It's human papilloma virus (HPV).

In the past, these cancers were most often linked to tobacco and/or alcohol abuse. Now it's recognized that most oropharyngeal cancers contain HPV. These mouth and throat cancers have been rising dramatically. Those related to smoking and alcohol, without the presence of HPV, have declined in the last 20 years.

These tumors mostly occur in the middle region of the throat, the base of the tongue and the tonsils. HPV is the same virus that causes cervical cancer. Some experts predict that HPV-caused mouth and throat cancers will become more common than cervical cancer by 2020.

There are about 200 different strains of HPV. Most often we are not aware that we have been exposed. When one of the strains invades the skin, it can cause common warts. These occur primarily on the hands and on the soles of the feet (plantar warts).

Common warts almost always go away on their own in people with normal immune systems. It may take many weeks or even months to see them disappear. Freezing them or applying medicines can speed the healing.

About 30 of the HPV strains can be passed from person to person during sex. This can occur with just skin-to-skin contact.

With sexual exposure, as with other exposures, HPV usually doesn't become active enough to cause symptoms. When it does invade the area in and around the penis, vagina and anus, it causes genital warts.

Besides skin, HPV transmitted during sex can invade the cells that cover the vagina, cervix, anus, mouth, tongue and throat. These cells make up the mucous membranes. Once the viruses get inside the cells, they become active.

HPV can change normal cells to ones that appear pre-cancerous. Even in these cases, a normal immune system most often will stop the process from advancing to a cancer. But even with a healthy immune system, cells can become cancerous. Some of these cancers can be very aggressive.

What Changes Can I Make Now?

The classic patient with head and neck cancer used to be a heavy-smoking, hard-drinking man of middle age or older. Today, men still develop these cancers three times as often as women. However, the men diagnosed with HPV oropharyngeal cancer typically do not smoke heavily or abuse alcohol. And they are often younger.

Sexual contact, oral sex and deep kissing transmit oral HPV. The likelihood of contracting oral HPV is directly linked with the number of sexual partners. And oral HPV is eight times more common in people who report ever having had sex.

Diagnosing HPV-related oral cancer at an earlier stage greatly improves the chance of cure. See your doctor if you have one or more of these symptoms for more than two to three weeks:

• A sore in your mouth or on your tongue that doesn't heal
• Persistent pain with swallowing or sore throat
• A lump in your neck that persists

There is some good news about HPV-related oral cancers. They are less likely to kill than the ones caused by tobacco and alcohol.

While there's no proof yet, HPV vaccination is probably the best way to decrease the risk of oral cancers linked with HPV.

However, if you have picked up an oral HPV infection, you still might be able to reduce your risk of developing cancer. Here's how:

• Avoid use of all tobacco products.
• Drink alcohol in moderation. This means no more than two drinks a day for men or one drink a day for women.
• Eat a well-balanced diet that is rich in fruits and vegetables.
• Get regular exercise.

What Can I Expect Looking to the Future?

Of the 200 different strains of HPV, serotypes 16 and 18 are the ones most strongly linked to oral cancer. The two available HPV vaccines provide excellent protection from infection with both serotypes. But you must get the vaccine before exposure.

Now that many pre-teens, teens and young adults of both sexes are getting vaccinated, we should see a decrease in oral cancer in the future. But vaccination won't help the millions of people already infected. Their best strategy is healthy lifestyle choices and early detection.