Prostate cancer drug touted
Healthy men over 55 who are concerned enough about the risk of prostate cancer to undergo annual PSA screening should consider taking the drug finasteride daily to reduce their risk of developing the disease, according to a new prevention guideline released Tuesday.
“If a man is interested enough in being screened, then at least he ought to have the benefits of a discussion” with his doctor about taking the drug, Dr. Barnett S. Kramer of the National Institutes of Health said at a news conference revealing the guideline.
Kramer was co-chairman of the panel that developed the recommendation for the American Society of Clinical Oncology and the American Urological Assn. It will be published in the March issues of the Journal of Clinical Oncology and the Journal of Urology.
The most likely initial candidates to take the drug would be men who are African American or who have a father or brother with the disease, factors which sharply increase risk, said Dr. Jack Jacoub, a medical oncologist at Orange Coast Memorial Medical Center in Fountain Valley, who was not a member of the panel. Many physicians have already been prescribing it for their patients at the highest risk, he said.
The recommendation targets men with a normal reading on the prostate-specific antigen or PSA, test, which is considered the best indicator of the presence of a tumor, because clinical trials of the drug covered only such men.
The panel stopped short of recommending that all men take the drug because clinical trials have not yet shown that it reduces deaths.
Prostate cancer is the second-leading cause of cancer deaths among men, behind lung cancer, with 186,000 new cases diagnosed and 28,660 deaths each year.
Finasteride is used in low doses under the brand name Propecia as an anti-balding drug and in higher doses under the name Proscar for shrinking enlarged prostate glands. The dose recommended for cancer prevention is the same dosage used in Proscar.
The drug interferes with the production of male hormones, starving the tumors of fuel they need to grow.
A major clinical trial reported in 2003 showed that finasteride reduced the risk of prostate cancer by about 25% in men who took it, preventing about 15 cases in every 1,000 men. That means 71 men would have to take the drug for seven years to prevent one case, Kramer said.
Another drug in the same family, called dutasteride, or Avodart, is thought to be even more potent and is undergoing clinical trials for prevention. It is also recommended in the guideline.
The medical groups did not issue new recommendations after the completion of the 2003 trial because it appeared that finasteride might have been promoting the growth of more aggressive tumors at the expense of those that are more benign.
“Now we know this is not the case,” Jacoub said. Subsequent studies have shown that shrinkage of the prostate caused by finasteride simply made the aggressive tumors more easily discovered.
The drug does have side effects in some men, however, including reduced potency and loss of sexual desire. Those effects can go away after a couple of months. On the other hand, the drug can result in reduced incontinence and fewer urinary problems.
Cost can also be a problem. The pills cost $2 to $3 a day, or about $1,000 per year, and most insurers do not cover them for cancer prevention.
Speaking at the news conference, panel member Dr. Howard Sandler of Cedars-Sinai Medical Center said: “If I tried the medication for a month or two and I got some side effects, then for me personally the benefit wouldn’t be worth the risk.” But if there were no side effects, he added, “I might sleep better at night.”
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