DALLAS June 2, 2011 In a multicenter clinical trial, UT Southwestern Medical Center researchers have found that higher doses of stereotactic radiation therapy requiring fewer treatments are safe and effective for patients with low-to-intermediate-risk prostate cancer.
Results of the trial, available in the Journal of Clinical Oncology, showed that stereotactic body radiation therapy (SBRT), which delivers ultra-precise radiation, was effective in treating patients with localized prostate cancer in five 30-minute sessions every other day over two weeks. That compares to the typical radiation protocol for prostate cancer of 42 to 45 daily treatments administered over eight to nine weeks.
"We were trying to develop a fast, convenient, outpatient, non-invasive treatment," said Dr. Robert Timmerman, vice chairman of radiation oncology and professor of neurological surgery and senior author of the study. "In the low-risk population, there are a lot of good options, but none of them are altogether convenient. The most convenient treatment would finish quickly without the need for a prolonged recovery."
SBRT has been used in the last decade to treat patients with lung, liver and brain cancers. The current study tested whether high-potency treatments would work in a moving target like the prostate, which moves considerably due to normal bladder and bowel filling.
"We're trying to kill the prostate cancer, but without injuring the urethra, the bladder or the rectum," Dr. Timmerman said. "Each treatment had to be very potent in order to get the full radiation effect in only five treatments."
To avoid injury to healthy tissue, researchers used beams of radiation that were just millimeters larger than the target itself. That narrow scope helped avoid consequences such as rectal injury, impotence and difficulty urinating.
Prostate cancer is the most common cancer in men, with some 200,000 diagnosed each y
|Contact: Robin Russell|
UT Southwestern Medical Center