By Robert Pear, The New York Times

WASHINGTON — Doctors who have a financial interest in radiation treatment centers are much more likely to prescribe such treatments for patients with prostate cancer, Congressional investigators say in a new report.

The investigators, from the Government Accountability Office, said that Medicare beneficiaries were often unaware that their doctors stood to profit from the use of radiation therapy. Alternative treatments may be equally effective and are less expensive for Medicare and for beneficiaries, the report said. In other recent studies, the auditors found a similar pattern when doctors owned laboratories and imaging centers that billed Medicare for CT scans and magnetic resonance imaging.