Man’s best friend could also be a lifesaver in the fight against cancer. Scientists said on Friday dogs can be used to detect bladder cancer by smelling urine.
There is already anecdotal evidence of dogs alerting their unsuspecting owners of skin cancer by persistently sniffing suspicious moles which were later diagnosed as malignant.
Now, in research published in the British Medical Journal, scientists have shown dogs can identify bladder cancer by detecting chemicals in urine emitted by cancerous cells.
“Dogs can be trained to detect some odor characteristics for bladder cancer,” Dr. Carolyn Willis, of Amersham Hospital in Buckingham in central England, said in an interview.
Cancer cells are thought to give off organic compounds with distinctive odorous that dogs can detect even in very small quantities.
Willis and her colleagues trained six dogs of varying breeds and ages to identify urine samples from 36 bladder cancer patients among 108 healthy volunteers.
Developing better tests
Each dog did nine tests which involved selecting the urine from a cancer patient from six other samples by lying down next to it.
The dogs had an average success rate of 41 percent, which Willis said is significant because it would have been 14 percent by chance alone.
During the training phase of the study, the dogs consistently identified a urine sample from a healthy control patient as cancerous. Further tests confirmed the volunteer did in fact have the disease.
Willis believes dogs could play an important role in helping scientists identify the compounds emitted by cancerous cells, which could then be used to develop better tests.
“The principal aim is to use the dogs to help us find specific markers for cancer,” she said.
“A lot of our research will be geared towards trying to decide what it is the dog has picked up in the bladder cancer samples.”
Bladder cancer is the ninth most common cancer worldwide with 330,000 new cases each year and more than 130,000 deaths, according to the International Agency for Research on Cancer in Lyon, France. Smoking is a leading risk factor for bladder cancer.
Willis and her team also plan to use dogs’ smelling ability to help them identify markers for other types of cancer.
