NASA's ENose, a device used to determine ammonia leaks in space shuttles, is believed to have the capability to sniff for cancerous tissues in humans. The ENose is a device based on 16 different polymer films. It can be taught to learn to recognize a compound or a combination of compounds. When even a single molecule of what it is that people want to identify is absorbed by the ENose, the polymer films react differently to the substance. Hence, each compound, or a combination of compounds, would elicit a unique response pattern from the device.

The ENose's creators believe that it could be taught to learn how to sniff for cancer tissues. During surgery, doctors have had to rely on visual inspection based on scans taken earlier. However, in some parts of the body (the brain particularly), cancerous tissues can be difficult to identify even with the scans. That's where the ENose comes in to indicate which part, exactly, has cancerous tissues. Reportedly, the ENose was already able to diagnose not only lung cancer but also diabetes patients who've breathed onto it. Eventually, the ENose could be linked to imaging devices that could point out the cancer-ridden tissues in real time while the ENose does its job.