Dogs ‘can tell if you’re getting bowel cancer’

Believe it or not, dogs can sniff out bowel cancer in breath and stool samples, with a very high degree of accuracy, even in the early stages of the disease, a new research has revealed.


According to researchers, the man’s best friend’s sense of smell is 1,000 times more sensitive than a human’s, and as a result it can apparently pick up chemical compounds specific to certain cancers.
In the research, published in the ‘Gut’ journal, a labrador detected traces of cancer with more than 90 per cent accuracy from samples provided by volunteers.

In fact, over several months, the researchers in Japan used the labrador to carry out 74 sniff tests. Each test group comprised one sample from a patient with bowel cancer and four control samples from those who were clear. The samples were randomly placed into five boxes.

The labrador, specifically trained to scent chemicals associated with bowel cancer, first sniffed a breath sample from a patient known to have the disease. It then walked along the boxes sitting in front of the sample it believed matched the cancer scent. The test was repeated with different boxes.

The labrador’s ability to detect cancer in breath samples was 95 per cent accurate overall, and 98 per cent accurate for stool samples. “The accuracy was high even for early cancer,” ‘Daily Mail’ quoted the researchers as saying.


The results were not affected by whether the patient smoked, the presence of non-cancerous bowel disease or inflammatory bowel disease.


“This study shows that a specific cancer scent does indeed exist and that cancer-specific chemical compounds may be circulating throughout the body. These odour materials may become effective tools in (bowel cancer) screening.


“In the future, studies designed to identify cancer-specific volatile organic compounds will be important for the development of new methods for early detection,” the researchers said.

However, the researchers behind the latest study say this has limited value as it picks up only one in ten cases of the disease’s early stages. But they hope that cancer-specific compounds detected by dogs could be incorporated into a new sensor that can be used to test samples as part of screening.

Nell Barrie, science information officer at Cancer Research U.K., said, “Although some dogs seem to be able to smell cancer in certain situations, we’re still a long way from understanding exactly what they are detecting and this small study in one dog doesn’t give us any new clues.”