Is that tumor cancerous, and how fast might it spread?

Pathologists have to answer those tricky questions every day.

Now a tool... normally found in crime labs...is in the hands of doctors to help them do a better job of catching cancer.

This is what a doctor sees viewing a tumor biopsy under a microscope. They have to judge by cells' visible features whether they're cancerous and if so , how aggressive.

"If you wanted to look at the edge of a tumor, one of the things that you want to know is that edge rapidly growing, is it an aggressive edge, or is it somewhat dormant or is the tumor not going to grow?" Now biochemist Richard Caprioli is helping them to also see the molecules involved in cancer and its spread. "Each one of those colors represents a different molecular signature that describes those different aggressive, less aggressive, and normal tissue levels."

He and his team at Vanderbilt University are developing what they call molecular imaging. It uses an instrument called a Mass Spectrometer, long used by chemists in places like crime labs. It detects the types and amounts of the various molecules in a sample.

But instead of destroying samples by pulverizing and dissolving them, Caprioli's method uses lasers to analyze intact tissues. As he wrote in the "Proceedings of the National Academy of Sciences," that lets them see not only the levels of telltale molecules but their location---like those important edges. "And now we're able to say yes, that is a very aggressive molecular pattern, or not." Caprioli says the technology is already being adopted by some hospitals to improve.

Cancer is just one example of the technique's usefulness.

It can be used to analyze any type of tissue such as Alzheimer's Disease plaques.