Wednesday, March 22, 2006

ANDY DWORKIN

Across the country, urologists increasingly give men with localized prostate cancers hormone-blocking treatments normally used on late-stage cancers.

Doctors hope that early use of the testosterone-fighting weapon might keep the cancer from spreading in the body.

But that is probably a pipe dream, Oregon Health & Science University researchers say.

In a group of 276 men who had this treatment at OHSU, almost one in 10 died from prostate cancer within five years.

“Ten percent dying at five years from any localized prostate cancer is not good,” said Dr. Tomasz Beer, director of OHSU’s Prostate Cancer Research Program. “What this suggests to me is that this treatment is not very effective.”

Androgen deprivation therapy works by lowering levels of male hormones, including testosterone, which can spur prostate cancer cells to grow. This is often done with drugs, though some men have their testicles removed. The treatments have significant side effects including sexual problems, osteoporosis, high cholesterol, hot flashes, fatigue, anemia, weight gain, forgetfulness and insomnia.

One nationwide survey of more than 100 urologists, run by the University of California at San Francisco, found that 14.1 percent of men with localized cancers are now using androgen deprivation therapy. Older, poorer and less-educated men, as well as those with more aggressive-seeming tumors, got the treatment more often.

The problem, Beer said, is no one has done a study randomly assigning men with local tumors to hormone deprivation or another treatment. Such random studies are the best evidence of whether a treatment works. Beer and co-workers didn’t do that study, but rather went back to a group of men diagnosed in the mid-1990s, studying the roughly 8 percent who got hormone-blocking therapy.

Because the researchers didn’t compare with a group randomly given other treatment, Beer can’t say exactly how much the treatment hurt or helped. But the death rate was high enough that Beer said androgen deprivation looks ineffective for early tumors. He said a random trial testing the treatment is probably not a good idea because the risks apparently offer low benefits.

It’s not clear why the therapy doesn’t help. Perhaps prostate tumors grow sensitive to testosterone only after they spread beyond the prostate, Beer said.

Limiting a man’s hormones is still a good idea in advanced cancers, when a tumor has spread beyond the prostate, Beer stressed.

“Without question, this remains the gold-standard front-line treatment for metastatic prostate cancer,” Beer said.

Source:
Study casts doubt on prostate cancer strategy
OHSU - Testosterone-blocking hormones did not appear to slow the spread in men with localized cases March 22, 2006