Intelligent scalpels?

I know that the majority of you are pre-med and some of you might be headed toward a career in surgery. My father was a pathologist and one of his important tasks was to perform frozen sections on surgical specimens from patients on the surgery table to determine if the surgeon had excised past the margins of the tumor. When I was a teenager I would sometimes accompany him to the lab if he had a call on a saturday. The procedure is fairly simple, the tissue is placed on a metal post, covered with a viscous gel matrix, placed in a cryostat to freeze and then sections were cut from the frozen block using a microtome in the cryostat. the sections are then fixed to a glass slide and stained before the pathologist analyzes the samples to call back to the surgical suite to tell the surgeon whether (s)he needs to excise more or not. The problem is that this takes at least 20-30 minutes for each sample, all the while the patients are sitting on the table  under anesthesia and the surgical team is just waiting.

I bring this up because earlier this week I saw a feature in Science that a company has developed a ‘smart’ scalpel, the iKnife, that can detect whether it is cutting cancerous or normal tissues. The scalpel can essentially sniff whether or not cancerous tissue is being cut. It does this by using a cauterizing (heated) blade that volatilizes compounds from the cells like phospholipids, metabolites, etc. Then a small port near the blade sucks in that smoke and volatile material and it is analyzed by a mass spectrometer. The pattern of molecules can be used as biomarkers to discriminate healthy tissue from cancer tissue. Pretty cool stuff!

http://news.sciencemag.org/2013/07/smart-knife-sniffs-out-cancer-cells