Dogs provide us with unconditional love and support, remind us to be grateful and present, and keep us walking and healthy well into our golden years. But it turns out, there’s another skill dogs have that can improve our lives tremendously. New research presented at the American Society for Biochemistry and Molecular Biology’s annual meeting in Orlando, Florida, suggests that dog’s highly evolved sense of smell can identify cancer in blood samples with about 97 percent accuracy.
Whereas humans only possess six million smell receptors in their noses, dogs have 300 million, which means they’re about 10,000 times better at detecting odors than humans. To conduct this new research, Heather Junqueira, the lead researcher at BioScentDx, and her colleagues used a form of clicker training to teach four beagles to distinguish between the blood samples of healthy patients and those with malignant lung cancer. Although one of the beagles was unmotivated to take part in the experiment, the other three managed to correctly identify the lung cancer samples 96.7 percent of the time and the normal samples 97.5 percent of the time.
“This work is very exciting because it paves the way for further research along two paths, both of which could lead to new cancer-detection tools,” Junqueira said. “One is using canine scent detection as a screening method for cancers, and the other would be to determine the biologic compounds the dogs detect and then design cancer-screening tests based on those compounds.”
The new study builds upon previous research, including a 2017 study that found a trained golden retriever and pitbull mix could identify the presence of lung cancer through breath samples with an extremely high accuracy rate. Prior to that, there was a 2013 study that found that trained dogs could detect breast cancer through blood samples 97 percent of the time. Then there’s the 2011 study involving a black lab named Marine who was 97 percent accurate in detecting colon cancer among loose stool samples, which made her success rate even higher than the tests doctors do.
In many of these studies, what was especially impressive was the fact that the dogs could detect cancer while it was still in its very early stages, which could make them even more useful than lab testing when it comes to detection. “Although there is currently no cure for cancer, early detection offers the best hope of survival,” Junqueira said. “A highly sensitive test for detecting cancer could potentially save thousands of lives and change the way the disease is treated.”
And cancer isn’t the only disease that dogs can assist in detecting. For more on this, check out this new study about how dogs can smell seizures before they start.