The findings, based on a review of 16,000 patients' medical charts, indicate there is not benefit to waiting on radiation and that immediate treatment after prostate cancer surgery does not increase the risk for incontinence or impotence.
 

"The common teaching has been, without clear evidence, that urinary incontinence and erectile function are worse when radiation is delivered earlier rather than later, but we didn't see any protective effect of delayed radiation compared to earlier radiation," said radiation oncologist Timothy N. Showalter, M.D., of the University of Virginia School of Medicine Cancer Center, who helped lead the study.
 

"It contradicts the clinical principle of delaying radiation as long as possible for the sake of the patient's side effects. It really speaks against that, and that ought not to be used for a reason to delay radiation."
 

The findings inject hard facts into a debate that has long divided the medical community. Many oncologists recommend radiation soon after prostate removal to kill off any remaining cancer cells, but others advise waiting until prostate-specific antigen tests indicate it's needed.
 

"Urologists tend to prefer to forgo adjuvant radiation therapy, because they fear the side effects, and radiation oncologists tend to prefer offering adjuvant radiation therapy because they fear the risk of metastasis [cancer spreading to other sites in the body]," Showalter said.
 

The take-home message for men receiving prostate cancer treatment, Showalter said, is that they should discuss the best strategy with their physicians based on their particular case.
 

"If someone's at generally low risk of prostate cancer recurrence and they have low-grade disease, it's probably still reasonable to take a delayed salvage radiation therapy approach," Showalter said.

"Once there's a real, compelling reason to deliver radiation, there doesn't seem to be a benefit to delaying their radiation in terms of avoiding complications. And we know from other studies, the earlier radiation is delivered, the more effective it is for these patients. The more likely it is to cure them."