As published in the Hartford Courant, June 6, 2006.Vaccine Treatment Takes Aim At Oral Cancer
Promising New Drug Was Originally Designed To Fight Cervical Cancer
By Hilary Waldman
A new cervical cancer vaccine headed for FDA approval this month
could also put a dent in new cases of oral cancer - one of the deadliest
cancers in the United States.
At least one-quarter of oral cancer cases may be linked to human
papillomavirus, the same sexually transmitted bug that causes cervical
cancer.
"In 10 to 15 years, we're going to find many fewer head and neck
cancers," said Brian Hill, founder and executive director of the Oral
Cancer Foundation.
Researchers started looking for new possible causes of oral cancer
when tobacco use dropped precipitously in the United States but the
incidence of oral cancer did not.
About 30,000 people will be diagnosed with oral cancer in the United
States this year, and only half of them will be alive in five years. The
death rate for oral cancer is higher than that for cancer of the cervix,
brain, liver, testicles, kidney or skin and for Hodgkins disease, a type
of blood cancer.
Six years ago, researchers at Johns Hopkins School of Medicine looked
at 253 patients with head and neck tumors and found HPV-16 - the
tumor-causing strain of the virus - in 25 percent of those patients.
HPV-positive tumors are most likely to occur in the throat and
tonsils and appear to be more responsive to treatment than tumors that
are not associated with the virus.
Although the presence of HPV in head and neck tumors has not yet been
convincingly linked to sexual practices, such as kissing and oral sex,
several studies suggest that there may be a connection.
Thus, said Hill and others, the vaccine called Gardisil will not help
people who are already sexually active. But advocates recommend that 11-
and 12-year-old children be vaccinated, a move that could drastically
reduce deaths from cervical and oral cancer.
For people who are already sexually active, there is no substitute
for a thorough annual examination by a dentist or a physician.
Caught in its earliest stages, oral cancer can be cured in 80 percent
to 90 percent of all cases. Once it has spread beyond the mouth,
however, only 30 percent to 40 percent of patients survive for five
years.
"Sixty percent of the American population sees a dentist every year,"
Hill said. "When exit surveys are done, only 7-to-15 percent of patients
said they had had an oral cancer exam while they were there."
Hill recommends that patients ask their dentists for an oral cancer
screening during every routine check-up.
A proper exam includes lifting the tongue with a gauze pad to examine
the underside and the floor of the mouth. The doctor or dentist should
then put one finger under the tongue and one under the chin to feel for
unusual bumps.
Some precancerous spots appear as white or red patches in the mouth
that linger for more than two weeks. Cancer is most likely to appear on
the sides of the tongue, the floor of the mouth, the soft palate or the
tonsils. It is very rare in the hard palate, cheeks or the top of the
tongue.
"There is no substitute for a good oral exam in the hands and eyes of
a knowledgeable clinician," said Dr. Ellen Eisenberg, a professor of
oral health and diagnostic sciences at the University of Connecticut
Health Center.
Some new technologies are emerging to help dentists detect and test
for oral cancer. One product uses an acid rinse and an ultraviolet light
stick to help dentists see suspicious spots in the mouth.
The product, called ViziLite, adds about $50 to $100 to the price of
a routine dental exam and is not covered by most insurance.
Another product called the oral brush biopsy allows dentists or
doctors to look at suspicious spots without sending the patient for an
immediate surgical biopsy.
The brush biopsy has been compared to a Pap test for the mouth. Using
a small tool, the doctor or dentist can remove a tiny sample of cells
from a suspicious spot. With the help of computer analysis, the test can
identify cancer cells in their earliest stages.
The brush biopsy is considered useful because it is not painful and
is simple to perform. Experts hope the availability of the test will
persuade doctors and dentists to test suspicious lesions quickly,
instead of waiting to see if they go away.
Dr. Sol Silverman, a professor of oral medicine at the University of
California, San Francisco, and a spokesman for the American Dental
Association, said dentists who find suspicious lesions might recommend
that the patient come back in a few weeks for a second look.
But, if the patient does not return, an opportunity for early
diagnosis could be missed, Silverman said. "What these technologies do
is accelerate the biopsy." |