I am often amused by the fact that with all of our new technologies and claims of scientific sophistication, sometimes a major advancement is right in front of our faces in the most unexpected place. When we first began hearing stories about dogs being able to smell cancer, I listened to this claim with a good deal of skepticism. (Our dog Champ’s sense of smell seems to be limited to sniffing out Kibbles ‘n’ Bits.) However, if you think about a dog’s keen sense of smell and the fact that cancer alters a patient’s body chemistry, the idea makes perfect sense. It was just too simple to believe in view of the complex diagnostic tools employed in detecting cancer. But new research reveals that not only can dogs be trained to detect skin cancers and differences in the urine of patients with bladder cancer, they can detect lung and breast cancer in the breath of cancer sufferers with astounding accuracy.
The knowledge that tumors exude odors not found in healthy tissue is nothing new; however, researchers are now realizing just how useful man’s best friend can be in detecting these smells. I first heard stories about dogs detecting melanomas in the late 1980s. Several dog owners claimed that their pets saved their lives by alerting them to cancerous skin lesions. Then, in a study conducted in 2004, a medical journal in Britain published the results of a double-blind, peer-reviewed study that concluded that dogs can be trained to recognize and flag bladder cancer. An interesting sidebar to the 2004 bladder-cancer study was that the dogs consistently identified as cancerous the urine of a patient classified as cancer-free. Because of the dogs’ persistence, the patient was tested again using conventional methods, and a previously missed kidney carcinoma was found.
In the latest study, cancer samples and control samples were collected and presented to five dogs that had been trained to lie down in front of cancer samples and ignore the control samples. (Cancer patients who had begun chemotherapy were excluded from the study, since chemotherapy has its own odors.) The dogs detected breast cancer with 88% accuracy and lung cancer with 97% accuracy!
Of course, further confirmation of accuracy is essential. Additional studies with other dogs are needed, but the ramifications of this latest study are immense. If the results hold up, using dogs to sniff out cancer could become an accurate, inexpensive, and quick way to screen for certain cancers. The possibilities for early detection are endless once the chemical compounds in the breath that most accurately point to the presence of cancer are identified. Even those who want to keep dogs out of diagnostics recognize that if dogs can help pinpoint specific chemicals characteristic of certain cancers, it could be a tremendous help in developing new diagnostic tools. Someone remarked that using dogs is unconventional, but it is the results that matter. I agree.
Have a great month, and give that dog a treat! He (or she) could save your life or the life of someone you love.