Yet another reason to love your pup. New research from The Journal of the American Osteopathic Association suggests that dogs – beagles, specifically – have the capacity to smell lung cancer with extremely high accuracy. Early detection is crucial for effective treatments, but currently, doctors rely on expensive and sometimes inaccurate CT and PET scans to diagnose lung cancer. Senior researcher Professor Thomas Quinn from Lake Erie College of Osteopathic Medicine thought there might be a better way, so he and his colleagues trained three beagles to "sniff out" non-small cell lung cancer in plasma blood samples.
"The olfactory acuity of a dog is at least 10,000 times more sensitive than that of a human, which is likely due to their more expansive olfactory epithelium and olfactory receptors and their ability to retain air in their nasopharynx during exhalation," the study authors explain. The researchers chose to work with beagles because they are scent hounds bred for hunting. "Beagles are a medium-sized member of the scent hound family and have 225 million olfactory receptors. In comparison, humans have 5 million olfactory receptors,” write the authors.
Following the dogs’ training, the researchers tested their ability to distinguish between blood samples from individuals with non-small cell lung cancer and blood samples from healthy individuals. They found that the dogs were able to successfully distinguish between the two types of samples, identifying the presence of cancer with 97.5% specificity, and 96.7% sensitivity.
"Right now, it appears dogs have a better natural ability to screen for cancer than our most advanced technology. Once we figure out what they know and how, we may be able to catch up," said Professor Quinn.
By this, he means that the end goal isn’t actually to use dogs themselves to detect cancers, but instead figure out how they do the detection and then mimic that part via our own technology. "We're using the dogs to sort through the layers of scent until we identify the tell-tale biomarkers," Quinn says. Ultimately, the scientists aim to develop an inexpensive over-the-counter screening test that would permit individuals to self-detect the presence of cancer by breathing into it, a cancer breathalyzer of sorts. Quinn and his colleagues are currently continuing their research to expanding testing the dogs' ability to identify several other forms of cancer, including breast cancer and colorectal cancer.