Can Dogs Sniff Out Cancer?

Researchers Training Dogs To Smell Cancer

(CBS)  Just because your dog is sniffing you, it doesn’t necessarily mean she’s detecting cancer. Safer's elderly dog, Dora, is constantly checking out him, as well as perfect strangers. It's probably just old-fashioned curiosity, Safer says, but for a handful of pet owners in this country and England, there is no question that their animals have a special gift.

Gill Lacey is one of them. Trudi, his Dalmatian, smelled trouble 25 years ago.

"One particular day, I noticed when she walked past me, she came towards me, sniffing at my leg. And I thought I'd just spilled something," recalls Lacey. "But when I looked, she was sniffing at a tiny mole on my leg."

That mole turned out to be a malignant melanoma, a deadly form of cancer, if not discovered early. Doctors removed the mole and a mass of tissue around it, and when Lacey left the hospital a month later, Trudi confirmed that the cancer was gone.

"Although they'd already said to me that it was clear, I felt reassured that it really was," says Lacey, who believes Trudi saved his life. "I'm convinced of that."

There are an increasing number of similar stories. Time and again, dog owners in England and the United States report much the same behavior. But until very recently, the medical establishments in both countries mostly ignored or dismissed such anecdotes.

Before her involvement in the study, Willis, a research dermatologist, was one of the skeptics. "Anecdotal reports on their own really don't prove very much at all," she says. "They are quite useful indicators of perhaps something to look at. But on their own, they don't provide any sort of proof of any particular phenomenon."

But she became convinced, in large part, because of a simple medical fact -- diseases do give off odors, and dogs, at least theoretically, can smell them.

"Back in the sixth century, I think Hippocrates was describing fruity smells associated with people with diabetes. And musty smells associated with liver disease," says Willis.

If dogs can recognize such odors, the implications for medicine could be enormous. Those noses might provide early detection that science cannot yet achieve. For a disease like prostate cancer, for instance, current detection through blood tests can be notoriously inaccurate.

No one has been more obsessed with the possibilities than Dr. John Church, the driving force behind the British medical journal study. A retired orthopedic surgeon, he believed for a decade that dogs could detect cancer.

He says that there was an element of skepticism, but the patients who were recruited were all "tickled to death because this was something brand new."

But now, in the wake of his study, he feels vindicated. "This is a first step in the right direction. I would say it is a great breakthrough in the sense that this is the first such presentation of a rigorous study of this type," says Church. "We regard this as a great breakthrough."

And there are more studies on the way. In California, there's a test of dogs’ ability to detect lung cancer, and back in England, with the help of a cancer researcher at Cambridge, Broom and Somerville are finishing up their own study on prostate cancer.

Final results are expected this year, but early tests show very high success rates. Meanwhile, the Amersham team is planning to move ahead on further research -- with their handpicked roster of specialists, of course. The team includes Biddie and Tangle, Oak and Dill, Bee, and a couple of pre-med rookies, Briar and Daisy.

"I personally see a day when you could use dogs to detect disease," says Church. "You've got a marvelous asset. You've got a wonderful tool."