/ 5 February 2005

‘Dogs are better than a CAT scan’

Humans and dogs can have an incredibly deep level of communication. Dogs know stuff about us that we don’t even know about ourselves, says American animal behaviourist Kirk Turner.

In 1999, Turner set out to determine whether dogs can sniff out cancer in humans.

A promising study in the United Kingdom and subsequent clinical trials in the United States have since showed that canines with their superior olfactory systems may be more accurate than machines in detecting the disease.

He and his partners from South Africa’s Council for Scientific and Industrial Research (CSIR) are establishing a dog training centre in the dusty district of Brits outside the capital, Pretoria, to explore this theory further.

A study conducted at the Pine Street Clinic in California, using dogs trained by Turner to identify the breath of lung, breast and pancreatic cancer patients since 1999, is currently under peer review.

”Basically, until the results are published in a medical journal I won’t make any claim as to what my results mean. What I can tell you is that dogs have an extremely high level of accuracy,” Turner said.

His findings may have profound implications for the detection of cancer, tuberculosis and even HIV/Aids, particularly in Third World countries where resources are low and the use of modern medical technology is scant and costly.

”The use of dogs in detecting diseases can have a potentially huge impact in the Third World, where a lot of money can be saved. Basically, it is a low-tech way of finding disease. I believe that it is possible to work with myriad other diseases, including Aids and tuberculosis,” Turner notes.

Trained dogs could also assist in validating the screening processes of Western technology.

”In my opinion, dogs are better at finding cancer than a CAT scan,” he said.

Anecdotal evidence over decades that dogs with their extremely sensory olfactory systems can smell cancer and other diseases, as well as the centuries-old Chinese belief to this effect, has nudged scientists in this direction.

Dogs have already proved their worth in fields such as assisting the blind and sniffing out drugs and explosives. It is not uncommon worldwide to hear of the family dog that emerges a hero from some crisis or other.

Last year, the first bit of significant research into canine cancer detection was published in the British Medical Journal.

Researchers at the Amersham hospital in England reported the findings of a study in which six dogs were trained to detect ”tumour-related volatile compounds” in urine samples.

The dogs achieved a 41% success rate — higher than that of state-of-the-art X-ray and CAT scan machines used by oncologists to search for signs of cancer. Urine samples from 36 patients with bladder cancer and 108 others without the disease were used in the study.

”They used urine while we use human air samples. Their tests were conducted in an environment with a lot of distractions — forensic dogs are generally trained this way. We will use a hospital-like environment with no distractions,” says Turner.

Training involves firstly ”imprinting the smell of cancer” on the dog’s olfactory system, by exposing it to the breath of cancer patients contained in tubes.

Dogs are taught to react to the smell of the disease by, for example, sitting or lying down and are rewarded with a treat, he says. They also learn to differentiate between what they are expected to look for and unusual scents, such as eucalyptus and sunscreen.

”With any detection work, whether it is landmines you’re looking for or explosives, you always have to be careful of inadvertent signals by the dog handler,” he says.

Removing the handler while the dog follows the cancer scent trial in a clinical trial would eliminate this risk, he says.

Turner’s training methods differ slightly from the ”jerk and pull” methods employed by ”many people in the dog business”.

”I don’t like using fear of consequence as a training style,” he says. ”To me a dog is a very special creature. The relationship between dog and trainer has to be about love and companionship. I use operant conditioning methods of the behavioural scientist BF Skinner.”

For the past 15 years, Turner has taught dogs obedience, agility and tricks in addition to treating behavioural problems. His most recent work centres on the behaviour of three Labradors and two Portuguese water dogs.

”All dogs have the same number of olfactory cells but those that are easily motivated make the best working partners,” he says. — Sapa-DPA