Radiotherapy tumor tracking study reported

CAPE CORAL, Fla., Feb. 16 (UPI) -- U.S. medical scientists say they have demonstrated that targeted radiotherapy in real-time prostate tumor tracking reduces side effects.

The multi-center clinical study of the new technology, manufactured by Calypso Medical Technologies Inc., involved high doses of radiotherapy for prostate cancer with tightly controlled, precise real-time tracking of the tumor targets.

Researchers said organ motion is prevalent and unpredictable during radiation therapy and can be caused by normal physiologic events, such as digestion, breathing or coughing. Tracking and responding to that motion is critical for radiation treatments because internal movement of the organ and tumor increases the likelihood the radiation beam will miss the intended target and deliver radiation to surrounding healthy tissue causing side effects.

"This is the first comparative study to show that margin reduction in prostate cancer radiation therapy has clinically significant and measurable benefits in decreasing acute toxicity and short-term side effects, said the study's lead investigator, Dr. Constantine Manz of 21st Century Oncology in Cape Coral, Fla., "By reducing acute toxicity, we hope these patients may also experience a significant reduction of long-term side effects."

The study is reported in the journal Urology.