Papillon dog

　　Dogs’ sense of smell is about a thousand times better than ours, so they are especially sensitive to certain special odors. We often hear news stories about dogs barking at a specific part of their owner’s body, which raises the owner’s suspicion and leads them to get a hospital checkup. After diagnosis, it turns out the owner has some type of cancer. So, is a dog’s nose really that sensitive that it can even smell cancer?

　　According to American researchers, dogs’ sense of smell has already been used in diagnosing thyroid cancer patients. Researchers experimented on 34 tumor patients, using dogs’ sense of smell for diagnosis. The experimental results showed an accuracy rate of 88%. The research team presented their findings at the annual Endocrinology Society meeting, noting that dogs have an "incredibly" keen sense of smell.

　　However, the British Cancer Research organization seems to disagree with this viewpoint. But if dogs can detect certain chemical elements, that could provide researchers with some insights and guide them to carry out new experiments. The thyroid is a gland on the neck that produces hormones to regulate human metabolism. Thyroid cancer is relatively rare and is usually diagnosed by needle aspiration of cells and testing hormone levels in the blood. Cancer cells are defective cells that are uncontrollable by the body. They have their own chemical mechanisms and release a type of "volatile organic compound" into the body.

　　Using dogs to monitor thyroid cancer is due to dogs having 10 times more olfactory cells than humans, enabling them to detect the unique odor emitted by cancer. Moreover, this method has already achieved some encouraging results in diagnosing intestinal and lung cancers. A research team from the University of Arkansas for Medical Sciences previously pointed out that dogs can differentiate between thyroid cancer patients and normal people by smell, and this discovery could be well utilized in medicine.