Dogs can smell cancer

Dogs can smell 10,000-100,000 times better than we can, a feature that can be of great use (police dogs that can find explosives) or not, as when taking a dog for a walk. Researchers have known for many years that cancer cells emit volatile compunds that normal cells do not, and anecdotal evidence suggested that dogs can detect skin cancer. To test this idea, researchers trained dogs to sit next to breath samples from patients with lung or breast cancer, but ignore breath samples from unaffected patients. The dogs make the correct choice 99% of the time using samples from lung cancer patients, and 88% of the time using breast cancer patient breath. Previous studies showed that dogs may be able to detect specific compounds in the urine of patients with prostate cancer. These detection rates are much greater than currently available technologies. This finding, if developed further, may lead to new early detection strategies.
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