It has long been suspected that man’s best friend has a special ability to sense when something is wrong with us. With a dog’s sense of smell being vastly better than a human’s and new research being brought forward we’re learning that dogs can provide a screening method for lung, breast, prostate, and multiple other cancers. How are dogs doing this? First you have to understand that dogs can detect odors at concentrations as low as one part per trillion, identifying scents with the human nose you have six million sensor receptors dedicated to smell – dogs however have 250 million.
One of the first notions that dogs could smell cancer was put forward in 1989 by two London dermatologists, who described the case of a woman asking for a mole to be cut out of her leg because her dog would constantly sniff at it, even through her trousers, but ignore all her other moles. It turned out she had malignant melanoma – a deadly form of skin cancer. It was caught early enough to save her life.
The scientific basis of the ability of dogs to detect the odor of cancer is believed to be linked to Volatile Organic Compounds produced by malignant cells. Dogs with their incredible sense of smell can detect the minute odors produced by the malignant cells, which is now understood to be associated with many cancers. There have been hundreds of studies published on the dog’s sensitivity and specificity at detecting early stage cancer. Most of the research points to accuracy levels well above 90% for the early detection of cancer.
Compelling evidence is showing that cancers hidden beneath the skin can be detected simply by dogs examining the odors emitted by the skin, urine or in the breath. Right now breath samples are being used to prove that dogs can detect cancer, and through this study scientists and doctors are trying to come up with a Breathalyzer test that works as good as the dog’s nose. So far, the only ones that can smell cancer in early stages are the dogs. There are many great benefits to dogs detecting cancers such as low cost, non-invasive screening, and the ability to be over 90% accurate.
Dogs smell like we see. We walk into a room and see the room; a dog walks into the room and smells the room. As more studies continue it is incredibly to think of what a difference dogs could make, providing quick, painless and early cancer detection in humans. It is the cancer researchers’ hope that in the future dogs can help detect cancer from the comfort of a doctor’s office.