Cancer can often be cured today if caught early enough. Unfortunately, people have to wait until symptoms appear before their doctor can pinpoint the specific test to be performed. Now researchers say they are on the trail of a new approach that can routinely screen your blood for any type of cancer--an electronic nose. Look for a blood test based on their work within five years. R.C.J.
Anecdotal evidence that dogs can detect cancer by smell inspired researchers to combine clever chemistry with optical detectors to craft an electronic nose that they claim can not only screen for any kind of cancer, but also determine whether it is aggressive. A University of Massachusetts chemist and veterinarian collaborated with a Georgia Tech biochemist and materials specialist to craft the laboratory detection system, which they hope to develop into a universal blood test for cancer. Like the red, green and blue pixels that mix to represent any color, three different kinds of nanoparticles can mix to cover the whole spectrum of cancer cells, the researchers found. The fluorescent nanoparticles are mixed with blood or tissue samples, where they bind to suspicious cells and, depending on the combination of particles that light up, indicate whether the cells are metastatic (capable of spreading beyond the initial tumor site).