It’s true when they say animals can sense things humans cannot. For centuries, humans have easily bonded with dogs since they offer so many attributes that improve our lives. Dog senses allow them to protect and support us emotionally and physically.
In fact, dog’s olfactory abilities (sense of smell) allows them to detect cancer and diabetes in humans. While humans are ruled by their visual cortex, dogs are dominated by the olfactory cortex and thus carry 25 times more smell receptors than people. These more refined capabilities for smell are made up of 125 to 220 million sensitive smell receptors. The receptors are about 100,000 to a million times more receptive than the smell capabilities of humans.
We understand that dogs have excellent senses of smell, but how does a dog’s nose detect major illnesses? Plentiful research shows not only how dogs are able to detect illnesses, but that they can also be trained to identify cancerous smells in humans:
How Do Dogs Smell Cancer?
Research shows that dogs can detect cancer based upon the idea that cancerous cells release metabolic waste and toxins that differ from healthy cells in the body. These different smells allow dogs to detect the earliest stages of cancer. Dogs can detect chemical traces of disease in fractions of a trillion parts. Even trained dogs can detect melanoma, a type of skin cancer by sniffing near skin lesions. In addition, other studies demonstrate that dogs are able to detect prostate cancer by smelling patients’ urine. They may even be able to smell cancerous cells through a person’s breath.
Dogs have the natural ability to detect cancer, but research shows that dogs can be trained to identify cancer smells. A team of researchers from Berlin trained several dogs to sniff out various types of cancers like bowel, ovarian, bladder, skin, lung, and prostate cancer.
Several studies have demonstrated how dogs can detect cancer and the general success rate of the practice. The following studies show the progress that’s been made in canine cancer detection research:
- Pine Street Foundation research found that dogs were able to detect breast and lung cancer at all stages with approximately 90% accuracy. The study sample contained 55 lung cancer patients, 31 with breast cancer, and 83 healthy people. Five trained dogs (three Labrador Retrievers and two Portuguese water dogs were used for this study.
- According to news reports, a black lab named Marine, was able to identify colon cancer in a study containing 200 humans with the disease. The dog had a stunning 97% accuracy rate. The dog was 25% more accurate than the usual fecal occult blood tests normally used to detect the disease.
- More recent research from the European Respiratory Journal found that four dogs were able to identify lung cancer in 71 out of 100 patients with the disease. They were able to rule out cancer in 372 of 400 samples that did not contain cancer. A low rate of false positives, around 7%, was found in this study.
- A melanoma expert, Dr. Armand Cognetta, studied whether dogs can detect skin cancer. A dog, George, was able to identify the melanoma in 99% of patients and could differentiate between malignant and benign lessons.
- At the Gianluigi Taverna of Humanitas Research In Milan, urine samples were taken from 320 men with prostate cancer and 357 men who didn’t have the disease. The first group had different stages of cancer and although the second group did not have prostate cancer, they had other types of cancer. The dogs were able to predict the right type of diseases with 98% accuracy.
Dogs in Healthcare
Canines could play a major role in the future of healthcare since the potential to detect cancer, especially in the early stages, has numerous benefits. Many researchers believe, and hope, that dogs will be more actively engaged into patient care in the near future. Some researchers recommend that cancer-sniffing dogs will be most useful in labs where gas chromatographs can isolate specific smell compounds that can easily be identified by dogs. A breathalyzer can change colors according to several compounds in the breath that indicate cancer.
During the training sessions, diabetic alert dogs are rewarded when they smell the scent of low blood sugar in saliva samples. Programed to know they’ll receive a treat, they train the dogs to detect the correct smell. In addition, dogs who are trained to detect ovarian cancers, work only with blood samples in lab spaces.
In the future, we may see dogs who are trained as service pups, but who also have additional detection training. Not only can this help detect cancers soon (and possibly save lives), but dogs can act as therapeutic healers during our time of need. This is just one of many reasons to love dogs.