By Andrew M. Seaman
NEW YORK (Reuters Health) - Men who get an older and less costly form of radiation after their cancerous prostates are removed fare just as well as men who get a new and expensive type of radiation, according to a new study.
"What we demonstrate is that both (therapies) are very safe and effective after prostatectomy, and patients should feel very confident receiving either technology," said Dr. Ronald Chen, the study's senior author from the University of North Carolina at Chapel Hill.
Conformal radiotherapy (CRT) delivers radiation over a large area to kill cancer cells. Intensity-modulated radiotherapy (IMRT), on the other hand, directs radiation to a smaller area to protect surrounding tissue.
IMRT, which is newer and the predominant form of radiation for prostate cancer patients, also costs about $10,000 more than CRT.
"The way we design the radiation for the IMRT is more sophisticated and takes more time," Chen said.
He and his colleagues write in JAMA Internal Medicine that new prostate cancer treatment technologies increases costs by about $350 million each year - mostly driven by IMRT.
But researchers questioned whether the newer, more expensive and focused radiation led to better outcomes in prostate cancer patients.
Last year, Chen and his colleagues found IMRT was tied to a lower risk of stomach problems and better cancer control in men who were using it as a first-line treatment for early-stage prostate cancer, compared to men who got CRT (see Reuters Health article of April 17, 2012 here: http://reut.rs/13G0OMI.)
For the new study, the researchers used data on 457 IMRT patients and 557 CRT patients who already had their prostates removed and were receiving radiation to prevent or treat reoccurrences between 2002 and 2007. All were on Medicare, the government-run health insurance for the elderly and disabled.
The patients were followed through 2009 and the researchers found that the IMRT patients experienced just as many complications as those receiving CRT. Those included stomach problems, incontinence and erectile dysfunction.
What's more, those receiving CRT didn't end up needing more cancer treatments, compared to IMRT patients.
Chen told Reuters Health that they may not have seen a difference between the two types of radiation because doctors tend to use lower doses of radiation after prostate surgery and IMRT may not give as much as an advantage.
Or, he said prostate surgery can cause urinary and sexual side effects in patients and would diminish the difference between the types of radiation.
Dr. Matthew Cooperberg, a urologist from the University of California, San Francisco, who wrote an editorial accompanying the new study, told Reuters Health the new study also shows how fast the more expensive treatment was adopted, despite many head-to-head comparisons.
In the new study, researchers found no patients were getting IMRT in 2000, but it was the treatment for over 80 percent of patients by 2009.
"I think one of the points is that no one is going with the less-expensive option. IMRT has become the standard," he said.
SOURCE: http://bit.ly/MbBLb9 JAMA Internal Medicine, online May 20, 2013.