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HPV AND TONSIL CANCER
The research of an Ohio oncologist, Maura Gillison, is confirming early
data showing the annual increases in tonsil cancer among younger
patients are due, at least in part, to HPV infection.
Changes in sexual
behavior during recent decades have probably encouraged the spread of
the formerly-rare virus.
One HPV strain—transmitted mostly through oral
sex and French kissing—suppresses anti-cancer genes, allowing tumor
growth in the exposed tissue.
At Our Throats
A new form of tonsil
cancer is spreading rapidly. The cause isn't smoking and drinking but a
virus.Oncologist Maura Gillison was looking for patients with tonsil
cancer for a clinical study several years ago.
The first enlisted was a
malpractice lawyer, followed by a doctor, then a scientist. She joked
to a colleague that all she needed was a rear admiral. In walked a
member of the military brass. All were in their 30s, 40s and 50s.
People in their prime didn't used to get throat tumors. Head-and-neck
cancer, as doctors call it, was a disease of older problem drinkers who
also chain-smoked (more men than women). Years of exposure to scotch
and Lucky Strikes would damage the DNA of cells lining the throat,
leading to cancer.
But Gillison, 44, a professor at Ohio State University, was among the
first researchers to make a startling realization:
The old
cigarettes-and-alcohol form of the disease was being eclipsed by a new
form, caused by the same human papilloma virus (HPV) that causes
cervical cancer.
The tumors grow in the
tonsils or in the tissue that remains after tonsillectomy. The only
good news is that the prognosis for these patients is better than for
the old disease.
Gillison and researchers at the National Cancer Institute estimate that
4,000 people, 75% of them men, develop this new form of throat cancer
annually. That's only a tenth of head-and-neck cases, but it's half as
many people as get cervical cancer in the U.S.
More worrisome,
Gillison's work shows HPV tonsil cancer is increasing at a rate of 5% a
year, unusual growth for a cancer diagnosis, even though throat
infection with the HPV strain that causes it is exceedingly rare.
Any
spread of the virus could make the number of cases increase
dramatically.
"I'm very worried," says Otis Brawley, chief medical
officer of the American Cancer Society. Skeptics say the association is
not proven, and that too much of the work comes from just Gillison.
Both Gillison and Brawley think a solution may exist: Vaccinate all
boys, starting as early as age 9, with Merck ( MRK - news - people )'s
HPV vaccine, Gardasil, now heavily promoted for cervical cancer.
Gardasil, however, is
already the source of all sorts of controversy. Antivaccine groups
oppose it because of its high costs ($360 for three shots) and alleged
side effects; the FDA says the vaccine is safe. GlaxoSmithkline ( GSK -
news - people ) is developing its own HPV vaccine.
Gillison spent three years trying to draw Merck's attention to HPV
tonsil cancer. Finally, she is working with Merck to design a study to
see if Gardasil can affect HPV infection in the throat. Merck admits
studying the problem is "challenging" but says the potential is big.
Interested in cancer-causing viruses, Gillison started work on the HPV
problem in 1996 when she was finishing her Ph.D. and oncology training
at Johns Hopkins University. She signed up with a group studying HPV
and cervical cancer. But she switched to studying throat cancer
patients after finding a few research papers reporting cases in which
tumors had the DNA of the HPV virus inside them.
She was shocked to find a substantial number of throat tumors had the
HPV type. She also noticed something dramatic when she organized HPV
patients by the year they were born. Starting with patients born in
1935, there had been an increase in the number of cases every single
year.
Researchers realized that a big change in sexual behavior in the 1950s
and 1960s--mainly, that people had more sexual partners--had allowed a
virus that had been rare to spread throughout the population. Some
researchers say gay men and women seem underrepresented, possibly
because they catch the virus elsewhere in the body and develop immunity.
What appears to happen is that one strain of the HPV virus, which is
transmitted largely through oral sex, but also by French kissing or
even just sharing a water glass, suppresses two anticancer genes.
HPV tonsil cancer is not as lethal as traditional throat cancers, but
the treatment is still brutal. Martin Duffy, a 69-year-old Boston
economist and consultant who doesn't smoke and has run 40 Boston
marathons, dropped 30 pounds to 120 pounds while being treated with
Erbitux and radiation. He was diagnosed with tonsil cancer in February
and is slowly recovering.
The death rate in head-and-neck cancer has been dropping, but doctors
are still discouraged: It turns out the less threatening virus was
responsible for many of those cancers. James Rocco, a head-and-neck
surgeon at the Massachusetts Eye & Ear Infirmary, says, "We're
probably doing no better than we were 30 years ago."
[http://www.forbes.com/forbes/2009/1102/health-cancer-tonsils-virus-hpv-at-our-throats.html;
Matthew Herper, 10.15.09, Forbes Magazine dated November 02, 2009;
abstinence.net, 24November2009]
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