A new finding suggests that dogs can detect bowel cancer even in its early stage from the breath and stool samples with an accuracy as high as 95 percent. Scientists have opined that trained dogs may be helpful in early detection of the disease.
During the onset of cancer, some chemical compounds circulate throughout the body which a trained dog can sniff out from samples of breath and stool. The presence of these chemical compounds paves the possibility of developing tests to detect the disease before it can spread.
The team of researchers included those from St. Sugar Cancer Sniffing Dog Training Centre, Minamiboso, Chiba Prefecture in Japan, and Hideto Sonoda, Assistant Professor at Kyushu University. They used a well trained Labrador retriever that completed 74 sniff tests comprising of 5 breath or stool samples at a time of which only one was cancerous.
The samples were collected from 48 bowel cancer patients and 258 people with no bowel cancer or who had had cancer in the past. Half of the latter were collected from people with bowel polyps, a precursor to bowel cancer.
Besides, 6% of breath samples and 10% of stool samples were collected from this group from people with various gut problems like inflammatory bowel disease, ulcers and appendicitis. Samples of bowel cancer were taken from patients who had cancer in various stages including early stage.
In 33 out of 36 breath tests and in 37 out of 38 stool tests, the dog succeeded in detecting which sample was cancerous and which was not. Thus, the trained dog attained 95% accuracy for breath test and 98% accuracy for stool test.
This suggests that the cancer cells give off specific odors which can be sniffed by dogs since these cancerous cells circulate throughout the body and affect the breath and stool.