Dogs Sniff Out Prostate Cancer
Approach Associated With Few False Positives in Early Testing
June 2, 2010 (San Francisco) -- Dogs may be able to sniff out the smell of chemicals released into urine by prostate tumors, setting the stage for a new means of early prostate cancer detection.
In early tests, the approach produced fewer false positives than would be expected with the commonly used PSA test, French researchers report.
The concept isn't new. Other researchers have reported varying degrees of success using dogs to detect cancers of the skin, lung, and bladder, says researcher Pierre Bigot, MD, of Tenon Hospital in Paris.
The theory is that many tumors release chemicals with distinct odors that can be picked up by dogs, whose sense of smell is much more sensitive than that of humans, he tells WebMD.
Better Prostate Cancer Tests Needed
More accurate prostate cancer tests are sorely needed, says Anthony Y. Smith, MD, chief of urology at the University of New Mexico in Albuquerque.
While the widely used PSA test picks up a lot of cancers, it also has a high false-positive rate, he tells WebMD.
"If all the men with high PSA scores go on to have biopsies, fewer than one-third will actually have cancer," Smith says.
Plus, many men with early prostate cancer are unnecessarily treated because existing tests can't distinguish between life-threatening and slow-growing tumors, he says.
In the United States, one man in six will receive a diagnosis of prostate cancer during his lifetime, but a much smaller proportion -- one in 35 -- will die from the disease, according to the American Cancer Society.
Smith moderated a news briefing on the findings at the American Urological Association annual meeting.