Lung cancer is currently the leading cause of cancer death in Australia and while early detection is key to successful treatment, researchers have been investigating a unique way of finding the disease earlier.
Rather than focusing on x-rays, CT scans and biopsies, researchers from the American Osteopathic Association have revealed that beagles are capable of identifying lung cancer by scent. The latest study, published in the Journal of the American Osteopathic Association, saw researchers identify specific lung cancer biomarkers to help train three dogs, which could soon be used to develop simple and affordable over-the-counter screening products.
The beagles were chosen for their superior smell receptor genes and after eight weeks of training, were able to distinguish between malignant lung cancer samples and healthy controls with 97 per cent accuracy.
“We’re using the dogs to sort through the layers of scent until we identify the tell-tale biomarkers,” lead author Thomas Quinn said in a statement. “There is still a great deal of work ahead, but we’re making good progress.”
For the study, the dogs were led into a room with blood serum samples at nose levels. Some samples came from patients with non-small cell lung cancer (which makes up 80 per cent of all lung cancer cases) and others were from healthy samples.
The dogs thoroughly sniffed a sample and sat down if they detected cancer, or moved on if they didn’t. In the next part of the study, which is nearing completion of its second trial, the dogs are working to identify lung, breast and colorectal cancer by smelling samples of a patient’s breath.
Researchers believe the dogs are effective in detecting cancer using this method and are working on dividing samples into chemical and physical properties until specific biomarkers for each cancer are identified. The aim for researchers is to use the information to develop products similar to pregnancy tests, which Quinn envisions as a colour-changing device that people can breathe into to indicate a positive or negative cancer finding.
According to the study, current screening measures such as chest x-rays have a high false-negative rate, while CT scans often result in a high false-positive rate. As many as 90 per cent of missed lung cancers occur when using chest x-rays, with researchers pointing out that CT scans can have trouble identifying small, central, juxta vascular lung cancers.
“Right now it appears dogs have a better natural ability to screen for cancer than our most advanced technology,” Quinn said. “Once we figure out what they know and how, we may be able to catch up.”
It’s always important to talk to a GP if you notice problems with your lungs such as chest pain, wheezing, shortness of breath, a persistent cough or blood. Other signs of lung cancer can include unexplained weight loss, recurring bronchitis and pneumonia, tiredness and loss of appetite.