New advice that men over 75 should not be screened for prostate cancer won't quell the long-standing controversy over the usefulness of the blood test for the disease, cancer experts said Tuesday.

"It stokes the debate, I think," said Dr. Charles Ryan, a prostate cancer specialist at the University of California, San Francisco.

And several experts are looking ahead to new research that may provide more specific guidance for all age groups.

The U.S. Preventive Services Task Force, a panel of experts who guide national health care, issued its report Monday based on a review of past research. The task force found that screening can detect some cases of prostate cancer, but the benefits of treatment in men over 75 "are small to none."

Treatment often causes "moderate-to-substantial harms," including impotence and bladder control and bowel problems, the task force said, without evidence it saves the lives of these elderly men.

The panel did not recommend for or against prostate screening of men under 75 but suggested that doctors discuss the potential benefits and harms of the test with their patients.

"I think it's a very well done and justifiable recommendation," said Dr. Barnett Kramer, associate director of disease prevention at the National Institutes of Health. "They continue to say the jury is still out for men under 75."

Prostate cancer is the most common cancer in American men _ about 186,000 cases will be diagnosed this year, according to the American Cancer Society. It is the second leading cause of cancer deaths in men. But most tumors grow so slowly they never threaten lives.

Prostate cancer screening is done with two tests: a blood test that measures prostate specific antigen, or PSA, and a digital rectal exam. The blood test is controversial because the PSA level can be high for many reasons. A positive result from the test must be confirmed by a biopsy. And there's no agreement on the best way to treat it: "watchful waiting," surgery, hormone therapy, radiation or some combination of those.

Screening is "an area of very intense controversy," said Dr. Durado Brooks, a prostate cancer specialist for the American Cancer Society. "There are many doctors who believe staunchly that PSA testing should be done in all men and there are probably an equal number of doctors who believe very much that testing is of limited value."

Most major U.S. medical groups recommend doctors discuss the potential benefits and known harms of prostate screening with their patients and make individual decisions. And most agree routine testing shouldn't occur before age 50.

The cancer society's advice for screening doesn't set an age to stop screening but suggests that men shouldn't be offered screening if they aren't expected to live another 10 years, Brooks said

"That's because every 75-year-old is not created equal," he said.

While some have health problems and aren't likely to live long, others are "very active, very vigorous and have minimal health issues, and many of those men are going to live into their late 80s or 90s," Brooks said.

Ryan, in San Francisco, said age shouldn't be the sole measure. Continued...