A third study used single needle-biopsy samples from 395 UCSF patients scheduled to have their prostates removed. The gene test accurately predicted the aggressiveness of their cancer once doctors were able to see the whole prostate after surgery.
Using one current method, 37 of the 395 men would have been called very low risk and good candidates for monitoring. Adding the gene test put 100 men into that category, said another study leader, Dr. Matthew Cooperberg of UCSF. The gene test shifted about half of the men into either a lower or a higher risk category.
"It went both ways — that was the remarkable thing. In any category of risk it added independent information compared to the standard criteria we use today," Carroll said. "More work needs to be done, but, in my opinion, this is a very good start."
However, Dr. Kevin McVary, chairman of urology at Southern Illinois University School of Medicine and a spokesman for the Urological Association, said the test must be validated in more men before it can be widely used.
"It's not there yet," he said.
UCSF just got a federal grant to see how men choose treatments and whether this test might sway them.
"We throw all these numbers at them. Are they really going to make a better decision?" Cooperberg said.
Dean Smith, 60, a retired marketing executive from Mill Valley, Calif., is following his doctor's advice to monitor the cancer he was diagnosed with in March. He said a gene test may have made him more comfortable with that decision.
At least six of his friends suffered side effects ranging from urinary leakage to inability to have sex after having their prostates removed.
"I would suspect that having cancer and having to live with it would be very difficult for them," but it doesn't bother him, Smith said. "I will die from something other than prostate cancer, I guarantee you."
Marilynn Marchione can be followed at http://twitter.com/MMarchioneAP
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