Advertisement
YOU ARE HERE: LAT HomeCollections

THE CANCER ISSUE

Prevention: Is it just the right drug away?

October 20, 2008|Melissa Healy | Times Staff Writer

At 66 years old, Vincent Motyl has the gravelly voice and rumbling laugh of a man who's spent much of his life in a halo of cigarette smoke. He grew up amid the industrial soot of Pittsburgh in a houseful of smokers and started a two-pack-a-day habit at 18.

Motyl's father died of lung cancer 22 years ago, at 86; but the old man's longevity doesn't comfort the Culver City mortgage banker, who says he's tried to quit "30, maybe 40 times." He's down to about half a pack a day now. "But of course I think of lung cancer," he says.

So Motyl didn't hesitate to enroll when UCLA's Jonsson Comprehensive Cancer Center launched a clinical trial to test whether medication -- in this case, the arthritis drug celecoxib (also known as Celebrex) -- might reduce the odds of developing lung cancer in a smoker or ex-smoker. He didn't ask what the medication was, and he didn't worry about side effects.

It just made sense, Motyl thought: If a daily pill could prevent cancer, who would not take it?

It is a simple and compelling idea: If some chemical agent -- a common nutrient or a medication already in wide use, for instance -- could block, disrupt or reverse the processes that lead to runaway cell growth, then cancer might never need to be cured. It could be prevented.

If only, say experts in the field, the quest for cancer-preventing drugs were as simple as it sounds, or as readily embraced by physicians and patient advocates as it is by patients like Vincent Motyl. But the effort is an uphill struggle, for several reasons.

Focus and funding are two. Compared with the effort to find drugs to cure and treat cancer, the search for preventive medicine "has been the stepchild" of cancer research, motivating just a small corner of the cancer research community, says Dr. Victor Vogel, a researcher and breast cancer oncologist at the Magee-Womens Hospital/University of Pittsburgh Cancer Institute. "It's not sexy, it's not fancy, and for the pharmaceutical companies, it may not always be very profitable."

Vast stores of money, brainpower and hope have brought forth drugs capable of extending cancer patients' survival by months and sometimes years, say prevention researchers such as Vogel. Meanwhile, drugs shown to have driven down cancer rates in high-risk populations -- ones that have been shown, in studies, to spare people from the ordeal of becoming cancer patients in the first place -- have been mired in debates over side effects.

--

An unwary world

In recent years, the Food and Drug Administration has approved two medications -- the cancer drug tamoxifen and the osteoporosis drug raloxifene -- for certain women at high risk of breast cancer. In 1999, breast cancer activists greeted tamoxifen, the first to be approved, with deep distrust because it was found to increase the risk of blood clots, uterine abnormalities and cataracts in post-menopausal women.

A year ago, the FDA approved the second, raloxifene, for breast cancer prevention in post-menopausal women at high risk for breast cancer. The agency concluded that the drug could cut the rate of breast cancer in such women by 44% to 71%, with side effect risks far lower than tamoxifen.

However, patients may not receive that message. In advertising raloxifene directly to consumers, the maker of the drug -- Eli Lilly and Co. -- scarcely mentions the cancer prevention effects, choosing to market the drug primarily for prevention of osteoporosis.

The result, Vogel says, is that most women at high risk of developing breast cancer who could benefit from drugs such as tamoxifen and raloxifene have never heard of these options.

"We're trying to find better, safer drugs all the time and trying to overcome both public and physician ignorance about this," Vogel says. "But you cannot imagine how many people I have to convince."

--

Search far and wide

The federal government's comprehensive record of clinical trials (www.clinicaltrials .gov) lists 9,161 studies for pharmacological treatment of cancer in the United States but just 155 for cancer chemoprevention. And several of those 155 have been suspended.

Still, the number and diversity of agents under investigation for prevention is impressive. Researchers are exploring the use of arthritis, diabetes and asthma drugs for protection against lung cancers; a low dose of the cancer chemotherapy drug finasteride to suppress the development of prostate cancer; and drugs that include celecoxib, aspirin and other arthritis medications as well as common antibiotics to prevent the development of cancers of the colon and digestive tract.

An African sleeping-sickness drug called eflornithine, marketed as a drug to block unwanted hair growth, is thought to be promising in the prevention of a wide range of cancers, including those of the skin, esophagus, colon, prostate and cervix.

Statins -- the cholesterol-lowering drugs that have shown benefits far outside their prescribed use -- are also under study in the prevention of a variety of cancers.

--

A complex process

Advertisement
Los Angeles Times Articles
|
|
|