How does a dog detect an illness?

Cancer causes metabolic changes in the body. These changes lead to abnormal or higher levels of metabolic products in the bloodstream, exhaled air, skin and excreta. Dogs are used to detect illnesses based on their ability to smell such changes.

Diagnostic dogs are trained to detect the scent profile of cancer; the urine of prostate and breast cancer patients is used for this. Research indicates that dogs can identify several cancers in addition to those they are trained to detect.

Diagnostic dogs are important in healthcare, cancer screening and the development of new technology. A dog can be trained to detect a range of illnesses.

Research confirms the effectiveness of diagnostic dogs

Research shows that dogs detect cancer based on its scent profile. A dog trainer must be able to interpret the dog’s actions and behaviour during assignments.

“Jouko Vepsäläinen, Professor at the Department of Pharmacy at the University of Eastern Finland, tells the newspaper Karjalainen that cancer can be detected in people by smell.”

Karjalainen: Syövän voi haistaa ihmisestä , IS

“The two dogs picked out all the target specimens of MCF7 breast cancer cell cultures that they were trained to detect (10/10) as well as all the target specimens that they were not previously exposed to [A549 (5/5) and BG (5/5)], but did not pick out the control specimens or the cell culture medium. Thus, the sensitivity, specificity, and positive and negative predictive values for both dogs were 100%.” Uri Yoel MD1,2, Jacob Gopas PhD3,5, Janet Ozer PhD5, Roni Peleg MD1,6 and Pesach Shvartzman MD1,

Canine Scent Detection of Volatile Elements, Characteristic of Malignant Cells, in Cell Cultures, IMAJ article

“With 99% sensitivity, the olfactory test demonstrated that dogs have the ability to distinguish cancer patients from healthy individuals.” Tore Amundsen, Stein Sundstrøm, Turid Buvik, Odrun Arna Gederaas & Rune Haaverstad

Can dogs smell lung cancer? First study using exhaled breath and urine screening in unselected patients with suspected lung cancer, Acta Oncologica. 2014, Volume 53, Issue 3, Pages 307-315.

“It is well known that the domesticated dog possesses highly developed olfactory abilities.” Lucia Lazarowski & David C. Dorman

Explosives detection by military working dogs: Olfactory generalization from components to mixtures, Applied Animal Behaviour Science. Volume 151, February 2014, Pages 84-93.

“Dogs have smell receptors 10,000 times more accurate than humans’, making them highly sensitive to odors we can’t perceive. A new study has shown that dogs can use their highly evolved sense of smell to pick out blood samples from people with cancer with almost 97 percent accuracy. The results could lead to new cancer-screening approaches that are inexpensive and accurate without being invasive.” Experimental Biology

Study shows dogs can accurately sniff out cancer in blood Canine cancer detection could lead to new noninvasive, inexpensive ways to detect cancer, Science Daily

The process is as follows