CAN DOGS SMELL CANCER?
Breast cancer and lung cancer are two of the leading causes of cancer death worldwide, and early detection of the disease is, of course, essential. Scientific researchers now have astonishing evidence of the ability of dogs to contribute to early cancer detection as a result of their ability to smell one or more substances that indicate the presence of cancer. The evidence shows that a dog's extraordinary scenting ability can distinguish people with both early and late stage lung and breast cancers from healthy controls.
Other scientific studies published in major medical journals have confirmed the ability of trained dogs to detect both melanomas and bladder cancers. One study tested to discover whether dogs can detect cancers only by sniffing the exhaled breath of cancer patients.
In this study, five household dogs were trained within a 3-week period to detect lung or breast cancer by sniffing the breath of cancer participants. The trial itself consisted of 86 cancer patients (55 with lung cancer and 31 with breast cancer) and a control sample of 83 healthy patients. The dogs were presented with breath samples from the cancer patients and the controls, captured in a special tube, and trained to give a positive identification of a cancer patient by sitting or lying down directly in front of a test station containing a cancer patient sample, while ignoring control samples.
The study showed that dogs can detect breast and lung cancer with sensitivity and specificity between 88% and 97%. The high accuracy persisted even after results were adjusted to take into account whether the lung cancer patients were currently smokers.
Once this methodology has been standardized, dogs may be used in a more widespread way to help early detection of cancers, potentially saving thousands of lives. This is yet another instance of the myriad ways in which dogs can enrich human life.
For the complete Science Daily article, go here.