MONDAY, Nov. 29 (HealthDay News) -- The prescription painkiller
Celebrex might help prevent non-melanoma skin cancers, a small
study suggests.
But one expert was quick to note that the drug, which is most
commonly used to counter the pain of arthritis, has been linked in
some studies to an increase in the risk for cardiovascular
problems. So it isn't yet clear that Celebrex (celecoxib) is an
ideal choice to prevent cancers that could be treated by other
means.
"We have a lot of different treatments for non-melanoma skin cancers," noted Dr. Doris Day, a dermatologist at Lenox Hill Hospital in New York City. "I would want more information regarding the mechanism of action of Celebrex, because of the other risks," she said.
The report, funded by the U.S. National Cancer Institute and
Pfizer, the maker of Celebrex, is published in the Nov. 29 online
edition and the Dec. 15 print issue of the
Journal of the National Cancer Institute.
Non-melanoma skin cancers are common, comprising "the most
prevalent malignancies in the United States with an incidence
equivalent to all other cancers combined," according to study lead
author Dr. Craig A. Elmets, a professor of dermatology at the
University of Alabama at Birmingham. These tumors include basal
cell and squamous cell carcinomas of the skin, which are typically
linked to overexposure to UV rays from the sun or indoor tanning
booths.
Currently, there are no U.S. Food and Drug Administration
(FDA)-approved agents for the prevention of non-melanoma skin
cancers, although sunscreens are widely recommended for this
purpose, Elmets said. "However, even sunscreens are only modestly
effective at preventing non-melanoma skin cancers. The
demonstration that celecoxib can prevent these common malignancies
heralds an entirely new approach for the prevention of these common
malignancies," he said.
For the study, Elmets and colleagues randomly assigned 240
people with precancerous skin lesions called actinic keratoses to
treatment with Celebrex or placebo. The researchers looked at the
number of new lesions after three, six and nine months of
treatment, and again two months after treatment had stopped.
The investigators found that the number of new precancerous
lesions in both groups was the same.
However, by the end of the study, patients taking Celebrex had a
59 percent lower risk for non-melanoma skin cancers, compared with
patients receiving placebo.
However, the study was stopped early after the FDA found that
people in another trial that involved a similar drug had an
increased risk for heart attacks. There were no such problems in
this trial, the researchers noted, perhaps because the trial lasted
only nine months.
In an editorial, Drs. Frank Meyskens Jr. and Christine McLaren,
both of the University of California, Irvine, said that the finding
that Celebrex helped reduce cancers but not precancerous lesions
suggests that different mechanisms may be at work during different
stages of tumor development.
Celebrex is one of a class of drugs called COX-2 inhibitors,
which also include Bextra (valdecoxib) and Vioxx (rofecoxib). Vioxx
was withdrawn from the market in 2004 and Bextra in 2005 because
studies had suggested users faced heightened risks for heart
attack. Celebrex did not show such a level of heightened risk and
has remained on the market.
Commenting on the new study, Day said that even though she would
not recommend that people take Celebrex for the sole aim of
preventing skin cancer, it could prove an additional benefit for
people who are already taking the drug to battle their arthritis
pain.
"But for me it wouldn't be a first-line drug for people who have non-melanoma skin cancers, because of the other options and the cardiac risks," she said.
In the future this drug may be useful, at a lower dose, for
preventing these cancers while avoiding the cardiac risk, Day
added, but "I don't think this is ready for recommendation as a
preventive for non-melanoma skin cancers."
More information
For more information on skin cancer, visit the
U.S. National Library of Medicine.