By Charlie Schmidt
With the power to smell out small amounts of chemicals, trained dogs can easily detect explosives or illegal drugs hidden in suitcases. But growing evidence points to a different helpful role for man's best friend: detecting cancer symptoms before they develop. A study presented in American Urological Association Annual Meeting in Orlando Dogs have been shown to detect prostate cancer almost incorrectly in urine samples.
Doctors currently screen for latent prostate cancer by measuring levels of a protein called prostate-specific antigen (PSA) within the blood. Men without prostate cancer have very low or no PSA of their blood. An above-normal PSA could be an early warning sign of prostate cancer. However, elevated PSA may result from other diseases reminiscent of prostatitis. A biopsy is the one option to confirm the presence of prostate cancer.
According to the study's lead writer, Dr. Gianluigi Taverna, a urologist on the Humanatas Research Center in Milan, Italy, this decline reflects the necessity for higher screening tools. Taverna says it's possible that dogs could fit the bill although “more studies are needed to determine how they can be introduced into the health care system”.
Italian Defense Ministry dog handlers trained a pair of German Shepherds to detect the smell of prostate cancer by sniffing urine samples from men with prostate cancer. Taverna and his colleagues then presented the animals with 677 urine samples—320 of them from men with prostate cancer and 357 from men without cancer. The dogs definitely got their rewards: They correctly identified urine samples with prostate cancer 99% of the time. 97% of the time and without cancer.
Taverna's study was not the primary to indicate that dogs can detect prostate cancer. Researchers on the Tenon Hospital in Paris, France, Reported in 2011 that a trained dog classified prostate cancer with greater than 90% accuracy in 66 urine samples from men with and without prostate cancer equally. Taverna and his colleagues wanted to substantiate these findings with two dogs as an alternative of 1, and with a much larger sample size.
Evidence dating back greater than twenty years suggests dogs' ability to smell out other malignancies, including melanoma, and lung and breast cancer. In a previously reported case, Published in The Lancet In 1989, a Border Collie/Doberman Pinscher mix that always sniffs and pinches the identical mole on its owner's leg (but not other moles). The one which caught the dog's attention turned out to be fatal.
Taverna hypothesized that cancers emit chemical odors with tumor-specific “signatures.” This signifies that the odor emitted by a prostate tumor is different from the odor emitted by other kinds of cancer. Determining the particular compounds given off by prostate cancer that dogs detect is the following step in his research.
“This study shows that canine olfactory abilities have profound research and health delivery implications,” says Garnick. “They should be viewed with caution, but I look forward to the maturity of these data and hopefully confirmation of the results by other researchers.”