Using radiation or surgery to treat early-stage cases of prostate cancer in older men who have other health problems may provide no benefit and could even have adverse results, a study suggests.

Researchers at UCLA say most forms of prostate cancer are extremely slow-growing and do not result in health problems, while aggressive surgical or radiation treatment could bring serious side effects worse than the effects of the slow-growing disease.

Those include urinary incontinence, impotence and bowel issues, they said.

Aggressive therapies often do not help older patients with early-stage prostate cancer to live longer, the researchers report in the journal Cancer.

Surgery and radiation in older men did not result in a lowered death risk from prostate cancer because they were more likely to die from their other health conditions before seeing any benefit from the prostate treatments, lead researcher Timothy Daskivich said.

"In the past, we've relied on the basic argument that older and sicker men are much more likely to die of other things besides their prostate cancer [and] that exposing them to aggressive treatment and its debilitating side effects is a poor gamble," he said.

The study bears that out, he said. It tracked cases of about 140,500 men aged 66 and older diagnosed with early-stage prostate cancer between 1991 and 2007.

Men with other health problems, known as comorbid conditions, did not live any longer after receiving aggressive prostate therapy compared with men receiving no treatment, the study found.

"Now we've shown that aggressive treatment of these men is ineffective," Daskivich said. "This information will help these men better maximize the quality of their remaining years."

The study findings could aid prostate cancer sufferers who are also dealing with a number of comorbid conditions in deciding whether to seek aggressive treatment for the cancer, Daskivich said.

They could also help doctors attempting to counsel patients on whether to pursue treatment, he said.

"This data clearly defines a subset of patients who should avoid therapies that will only cause them problems they don't already have," he said.

Prostate cancer remains one of the most common diagnosed cancers in men, with an estimated 233,000 new cases predicted to be seen in the United States this year.