Cancer-sniffing dogs more widely used

Aug 26, 2015, 4:13 PM EDT
Happy mature female veterinarian examining dog in hospital
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Britain's National Health Service recently approved a trial for dogs capable of sniffing out prostate cancer. Dogs’ sense of smell can detect minute odors known to be associated with many cancers. Hospitals in the U.S. are increasingly looking at using dogs to sniff out malignant cells. Reuters reports:

"Dogs have got this fantastic sense of smell; three-hundred million sensory receptors, us humans have five million. So they're very, very good at finding minute odors. What we now know is that cancer cells that are dividing differently have different volatile organic compounds -- smelly compounds -- that are associated with the cells. And dogs with their incredible sense of small can find these in things like breath and urine," said Dr. Claire Guest who co-founded charity Medical Detection Dogs in 2008 to train specialist dogs to detect human diseases.
She added that the dogs' ability to sense chemical changes has been known throughout history but overlooked by modern medicine: "What dogs are doing is actually revisiting a way in which diagnosis has been done centuries ago. It was understood then that different volatiles - or smelly compounds - could be involved with changes in our body and may in fact enable someone to make an accurate diagnosis. But this has been very much forgotten. What the dogs are doing is finding the odors from bio-chemical changes in our body and this is opening a new way of diagnosing diseases and conditions in the future."
Researchers at UC Davis are turning to man’s best friend to help find some cancers that are tough to detect early on.
Their names are Alfie and Charlie—Charlie’s a girl by the way. The playful puppies will grow up to be the principal investigators in cancer research.
“Their smell is about 10,000 to 100,000 times more sensitive than humans,” said Dr. Hilary Brodie.
Studies have shown dogs are 90 to 95 percent effective at sniffing out cancer, but researchers don’t know exactly what dogs smell that signals malignant cells.
“That’s our goal is to one; to prove that indeed, that they can differentiate patients with and without cancer. and then to try to isolate, what is the molecular compound that is being detected,” he said.
Dog trainer Dina Zaphiris has trained more than 30 dogs to detect cancer. Alfie and Charlie will learn what cancer smells like by sniffing samples of breath, saliva or urine from people who already have throat or lung cancer. They’ll alert with a sit or down if cancer is detected.