By Hellen Nanzia
Dogs could the next revolution in the fight against prostate cancer. A dog’s remarkable sense of smell can detect minute odors known to be associated with many cancers, which are linked to volatile organic compounds produced by malignant cells. Dogs have a fantastic sense of smell; three-hundred million sensory receptors, while humans have five million.
Therefore, they’re very good at finding minute odors. 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 smell can find these in our breath and urine. Dr. Claire Guest who co-founded charity Medical Detection Dogs in 2008 to train specialist dogs to detect human diseases explained the concept.
Recently Britain’s National Health Service approved a trial for dogs capable of sniffing out prostate cancer in the hope that it could show up inaccuracies in the current PSA (prostate specific antigen) test.
Medical Detection Dogs gained approval from Milton Keynes University Hospital for further trials, after initial testing showed trained dogs can detect prostate tumors in urine in 93 percent of cases. The charity says dogs undergo training for a period of about six months, after which they can reliably identify urine with traces of cancer cells in it. At the charity’s facility the dogs do the rounds, sniffing a machine that holds eight urine samples. When they detect the sample that contains cancer cells, they stop and sit down by it, bark or lick the bottle to indicate they can smell the cancer. Dogs are initially rewarded when they detect any urine scent, and then later only rewarded when they successfully identify cancer cells in urine samples.
For Dr. Guest, this new method potentially saved her life. In 2009 her Labrador Daisy made her aware that she was suffering from the early stages of breast cancer when she began to nudge Dr. Guest’s chest. Daisy, now 11-years-old, is one of the dogs taking part in the trials in Milton Keynes.
“These dogs have the ability to screen hundreds of samples in a day; it’s something they find very easy, they enjoy their work. To them it’s a hunt game – they find the cancer,” she said.
The research also found that dogs were able to detect the cancer in 98 percent of the cases.