Promising Prostate Cancer Therapy

(AP)  Men with prostate cancer that doesn't appear to have spread have better survival chances when they get short-term hormone treatment along with standard radiation, rather than radiation alone, a small study found.

Almost five years after treatment, six men in the radiation-only study group died of prostate cancer; none of the men who got combined treatment died of prostate cancer. The study involved about 200 men.

Of the more than 200,000 U.S. men diagnosed each year with the disease, nearly half have the kind cancer involved in the study: An exam and imaging indicates it hasn't spread but other tests indicate it might have.

Treatment for such men often involves radiation alone or radiation combined with long-term use of hormone-fighting drugs, often for as long as three years or more. But long-term drug use may cause thinning bones, heart abnormalities that can lead to sudden death and impaired mental function.

The study found that using hormone-blocking drugs for six months had the same survival benefits as long-term use but without the potential health risks. Some men did have side effects including impotence, but that can occur with other prostate cancer treatments, including surgery and radiation.

"It's a very important and useful study and should have nearly immediate impact on the fashion in which men are treated," said Dr. Durado Brooks, director of prostate cancer programs at the American Cancer Society.

"Significant numbers of men are getting radiation only," Brooks said. That's partly because many men reject hormone-suppressing drugs when they learn about all the bad side effects from long-term treatment, he said.

Brooks said radiation plus short-term medication is likely to become prevalent given the study results.

Researchers studied 206 men aged 49 to 82 randomly assigned to receive about seven weeks of daily radiation treatments, or radiation plus six months of medication overlapping the radiation treatment. Six of those only on radiation died from prostate cancer while none of those getting combined treatment died from prostate cancer.

More than twice as many radiation-only men had evidence of cancer recurrence, 46 versus 21 in the combined treatment group.

The study by researchers at Boston's Brigham and Women's Hospital and Dana Farber Cancer Institute appears in Wednesday's Journal of the American Medical Association.

The patients had prostate cancer that physical exams and imaging tests indicated had not spread. But they also had high blood levels of PSA - prostate specific antigen - and high Gleason scores, which measure the degree of abnormality found in cancer tissue.

The high levels raise the possibility of cancer elsewhere, said lead author Dr. Anthony D'Amico, a radiation oncologist at both institutions.

The drug treatment studied involved flutamide pills three times daily with periodic injections of either leuprolide acetate or goserelin. The drugs suppress production of testosterone, which can fuel prostate cancer growth.

Men in the drug-radiation group had more severe impotence and more breast tissue enlargement than the radiation only group. But they had no obvious evidence of the potentially more debilitating complications of long-term treatment. Although those weren't specifically measured, they usually don't appear until after at least a year of treatment, D'Amico said.

In a JAMA editorial, Dr. Theodore DeWeese of Johns Hopkins University, said the study did not address how the drug treatment affected patients' quality of life. He also said the radiation dose was lower than is frequently given, which might explain the differing survival rates.

Still, he called the study "extremely important" because of the survival advantage shown.


By Lindsey Tanner