Early Cancer Detection: Dogs with frickin' laser beams

You may recall from several years ago, reports of dogs who could sniff out cancer. Based on odour, trained dogs could distinguish urine from bladder cancer patients from controls at a better-than-chance rate (mean success rate of 41% vs. 14% expected by chance alone in this study).

Since then, more canine cancer detection experiments have been done. In 2006, this double-blind study showed that ordinary household dogs could be trained to identify breast- and lung-cancer patients with incredible accuracy (88% and 99% respectively) and specificity (98% and 99% respectively) compared to conventional diagnosis and biopsy confirmation, based on breath scent. The dogs were able to 'diagnose' both early- and late-stage cancers.

Fast forward to 2008. While a Korean company is cloning cancer-sniffing dogs, a group at the University of Oklahoma - intrigued by the dogs, and having already published proof of concept to identify volatile compounds in breath - announced a project to develop a tool for laser-based detection of cancer biomarkers. The goal is to eventually develop an 'electronic nose' for rapid, accurate, non-invasive cancer diagnosis.

According to McCann, “Improved methods to detect molecules have been demonstrated, and more people need to be using these methods to detect molecules given off from cancer. We have developed laser-based methods to detect molecules. Mid-infrared lasers can measure suspected cancer biomarkers—ethane, formaldehyde and acetaldehyde.” McCann will use nanotechnology to improve laser performance and shrink laser systems, which would allow battery-powered operation of a handheld sensor device.

Because of the importance of early detection, this device - if sensitive enough to detect early-stage cancers with a simple breath test - could have major implications for survival rates. Unfortunately right now it's just a press release and, as pointed out in the release, an actual product is 5-10 years away, but in the meantime more biomarkers can be investigated and more cancers can be screened as candidates for laser-based diagnosis. As McCann states, "the science supports it, and the dogs tell us there is something there."