ST. LOUIS (AP) ­- Ten years ago, most of Dr. Brian Nussenbaum’s oral cancer patients were men over 60 who used tobacco and drank heavily.

Today, his patients with oral cancer look different. So does the risky behavior that seems to be leading to their cancer.

Nussenbaum, an ear nose throat doctor at Washington University, estimates that 70 percent of his cancer patients have tumors on the back of their tongues and tonsils caused by human papillomavirus-16.

Most of those patients are between ages 45 and 55. About half are women.

And experts suspect that all of them – men and women – got the HPV from oral sex.

Last week, Dr. Harald zur Hausen, a German doctor and scientist, was awarded the Nobel Prize for medicine for finding human papilloma viruses that cause cervical cancer, the second most common cancer among women.

In awarding zur Hausen the prize, the Nobel assembly said he “went against current dogma” in the 1970s when he discovered that certain types of HPV caused the cancer and that the DNA of HPV could be found in tumors.

More than 20 years passed before researchers at Johns Hopkins Kimmel Cancer Center reported a link between HPV and these specific throat cancers in 2000.

They and other medical experts suspect the increase in HPV oral cancer stems from a shift in sexual behaviors about 40 years ago, combined with a dramatic decrease in the number of tonsillectomies performed. Cancer from the HPV virus often develop on the tonsils.

In the John Hopkins study, researchers compared healthy people to patients with HPV oral cancer and concluded that people with HPV infections were 32 times more likely to develop the oral cancer than those without HPV. And people who had more than six oral sex partners in their lifetime were 8.6 times more likely to develop the HPV-linked cancer.

These findings have ramifications for anyone who is sexually active. Parents have another reason to think hard whether they want their adolescent daughters, and perhaps even sons, vaccinated with Gardasil, a drug that helps protect against human papillomavirus.

And even baby boomers who thought they’d dodged the STD bullet, may not have after all.

Experts believe the HPV lies dormant for years, perhaps decades, before causing the cancer. No one knows for how long, because there’s so little data on the disease. The National Cancer Institute determined recently that the rate of oral cancer caused by HPV has risen steadily since 1973.


Dr. Mark Varvares, chairman of the department of otolaryngology at St. Louis University, says it’s hard to get patients with HPV oral cancer to participate in studies.

“It’s extremely difficult because of the connotations of this being associated with people who are sexually promiscuous,” Varvares says.

The Johns Hopkins study was conducted using a computer system that provided anonymity, with hopes of getting honest answers.

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Nussenbaum says a lot of doctors spend very little time, if any, discussing the cancer’s link to oral sex. He’s given second opinions to several patients whose diagnosing doctors never mentioned HPV or its link to sexual behavior.

“In clinic, I let patients direct the conversation,” Nussenbaum says. “I don’t push or force the issue. It can get a bit uncomfortable especially when there are other family members, like children or spouses, in the room.”

Symptoms of HPV oral cancer can include difficulty swallowing, a sore throat that won’t go away, ear pain and a lump in the neck. Blood tests won’t detect this type of cancer. But blood and saliva tests can detect HPV. None are being used in mainstream clinical settings yet.

The only good news with this type of cancer is that the tumors are highly sensitive to radiation and chemotherapy.

Nussenbaum says that even with stage 3 and 4 HPV cancer, the chance of living for three years is nearly 90 percent. For patients with non-HPV cancer, the survival rate is usually about 55 percent.



“The tumor cells of patients with HPV cancer are different at the gene level than those with non-HPV cancer,” he says. “Even under a microscope, the tumor looks different. The shape and size of the cells are different.”

Dr. Mark Varvares, chairman of the department of otolaryngology at St. Louis University, notes how discovering HPV oral cancer has allowed experts to better understand the mechanics of managing it. Most major medical centers now treat it with chemotherapy and radiation and have had enough success that they’re trying to determine the lowest doses they can use while maintaining that cure rate, he says.

“As clinicians, we don’t like to pound patients with chemotherapy without any significant effect on the tumor. That’s a nightmare for us,” he says. High doses of radiation can cause permanent scarring and narrowing of the throat, problems with swallowing and dry mouth. Varvares estimates that about 30 percent of oral cancer patients must have permanent feeding tubes installed.

Experts are looking at different ways of preventing HPV oral cancer.

Varvares says experts are hoping to begin screening cervical cancer patients and their partners for oral HPV using the blood and saliva tests.

And Nussenbaum says experts are considering testing whether Gardasil can prime the immune system to fight the cancer. Typically, he notes, the vaccine is used preventively, so this could lead to a new way of using it.

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Meanwhile, everyone agrees, practicing safe oral sex with condoms and dental dams is the best way to guard against oral HPV, which can lead to the cancer. So is getting the word out that it exists.

Nussenbaum recalls telling a patient that she had HPV oral cancer and that patient turning to her two teenage daughters, looking them right in the eyes and saying, “See. I told you sex can kill you.”

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(c) 2008, St. Louis Post-Dispatch.

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AP-NY-10-12-08 1816EDT

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