A study, published in the journal Integrative Cancer Therapies, provides compelling evidence that cancers hidden beneath the skin can be detected simply by examining the odors of a person’s breath. It means that after a few weeks of basic “puppy training”, dogs can accurately distinguish between breath samples of lung- and breast-cancer patients and healthy subjects.

Some types of Cancer patients take a breath out with patterns of biochemical markers, since cancer cells emit different metabolic waste products than normal cells. The differences between these metabolic products are so great that they can be detected by a dog’s keen sense of smell, even in the early stages of disease.

Early detection of cancers greatly improves a patient’s survival chances, and researchers hope that man’s best friend, the dog, can become an important tool in early screening.