Too many men with low-risk prostate cancers, those whose level of prostate-specific antigen (PSA) is normal or below normal, still receive aggressive treatment, a new study shows.

Recent evidence has shown that among older men with low-risk prostate cancer, it's not the cancer they die from, but another condition. For these men, watchful waiting is probably better than surgery or radiation therapy, the researchers noted.

"The difficulty we have right now is that we need further efforts in research to understand who is who, and individualize treatment in a better way," said lead researcher Dr. Robert S. DiPaola, director of the Cancer Institute of New Jersey and associate dean for oncology programs and professor of medicine at UMDNJ-Robert Wood Johnson Medical School in New Brunswick, N.J.

Understanding more about prostate cancer will enable doctors to make better use of the therapies available, he added. "Obviously, there is a large population, if we knew who they were, (that) would not need that therapy," he said.

But on an individual basis, the decision whether to have aggressive treatment or not is complex, DiPaola noted. Because the decision may be different "depending on age, aggressiveness of the tumor, the PSA level, this is a call to action that patients need a very informed discussion. They need all those things considered, and the approach needs to be individualized," he said.

The report is published in the July 26 issue of the Archives of Internal Medicine.