Beagles can detect lung cancer with almost 97% accuracy

There have already been numerous studies in the past confirming that all dogs are in fact good, we’ve read the stories of dogs saving the lives of their diabetic owners, and some of us may have even attended a doggy de-stress day on campus. Our four-legged canine companions are making headlines once more – this time due to the study that shows dogs can accurately sniff out cancer in our blood.

The new study, led by Heather Junqueira at BioScentDx, revealed that dogs can use their highly evolved sense of smell to identify blood samples from cancer patients with almost 97% accuracy. Canine smell receptors are 10,000 times more accurate than those of humans, and therefore can provide a non-invasive, inexpensive, and highly sensitive test for detecting cancer.

Our four-legged canine companions are making headlines once more – this time due to the study that shows dogs can accurately sniff out cancer in blood

This would not be the first time that dogs would come to the rescue for humans, as man’s best friends have a long history within medicine. Dogs have approximately 125-130 million scent glands – compared to only around 5 million in humans. This gives dogs the intricate sense of smell which captured the interest of the medical world to help human diseases. Previous studies have identified that dogs can sniff out conditions including narcolepsy, migraines, epileptic seizures, as well as stress and anxiety in patients with post-traumatic stress disorder.

Alongside the basset hound and bloodhound, beagles have one of the best-developed senses of smell of any dog breed. John Paul Scott and John Fuller investigated canine behaviour in the 1950s – one behaviour was that of scenting abilities. They did this by putting a mouse in a one-acre field and timing how long it took dogs to find it: beagles managed to do so in less than a minute (compared to a fox terrier which took 15 minutes, and a Scottish terrier who failed altogether).

Previous studies have identified that dogs can sniff out conditions including narcolepsy, migraines, epileptic seizures, as well as stress and anxiety in patients with post-traumatic stress disorder

It is, therefore, no surprise that BioScentDx’s study involved four two-year-old beagles, which were trained to distinguish between normal blood serum and samples from patients with malignant lung cancer. Beagles are one of the most commonly used breeds in scientific research. Animal testing comes with a myriad of ethical debates attached to it, but what is it about beagles specifically that makes them the go-to breed for this research?

Journals and industry experts claim that beagles are the preferred breed because of their “good behaviour, characteristics, size, and other physical traits” and their “docile temperament.” The first ever experiment with this breed was at the University of Utah in the 1950s, and was known as ‘The Beagle Project’ and involved testing the impact of exposure to radioactive substances on lifespan. These experiments saw many dogs suffer severe bone fractures, and many dogs died from the radiation they were exposed to. In the UK, in 2004 7,799 of the 8,018 dogs used in testing were beagles (87.3%).

The first ever experiment with this breed was at the University of Utah in the 1950s, and was known as ‘The Beagle Project’ and involved testing the impact of exposure to radioactive substances on lifespan

The study led by Junqueira was very different from that of the first-ever beagle experiments. None of the beagles were exposed to harmful radiation, and instead underwent a form of clicker training to learn to distinguish the blood samples. It is reported that one of the dogs, named Snuggles, was unmotivated to perform, but the other three identified lung cancer samples 96.7% of the time, and normal samples 97.5% of the time.

The results of the study were presented to the American Society for Biochemistry and Molecular Biology at the 2019 Experimental Biology Meeting, and Junqueira commented: “Although there is currently no cure for cancer, early detection offers the best hope of survival… A highly sensitive test for detecting cancer could potentially save thousands of lives and change the way the disease is treated.”

It is reported that one of the dogs, named Snuggles, was unmotivated to perform, but the other three identified lung cancer samples 96.7% of the time, and normal samples 97.5% of the time

The Florida-based biotech company is currently experimenting whether dogs can sniff out breast cancer from breath samples, and hope to separate the samples into their chemical components to identify which substances the dogs are detecting.

Scientists all over the world are working to improve cancer detection, including with the use of AI, and Junqueira explained that the power of these puppies could also be harnessed to detect cancer in two ways: “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.”