Real-Time Mass Spec Aids Cancer Surgery

Chemists have combined mass spectrometry with laser surgery to quickly identify tumor tissue, a technology development that could speed up and improve cancer treatment (Anal. Chem., DOI: 10.1021/ac102613m). When surgeons remove tumors from patients, they must excise some healthy tissue surrounding the tumor to ensure that no cancer is left behind. But because cancer cells aren’t easy to spot with the naked eye, surgeons—and their anesthetized patients—must wait 30 to 40 minutes for a pathologist to check tissue samples before finishing an operation. Zoltán Takáts of Justus Liebig University, in Giessen, Germany, and colleagues have developed a faster technique based on laser desorption ionization mass spectrometry. In their method, they fire an infrared laser at tiny spots of tissue to generate an aerosol of ionized phospholipids that are analyzed by mass spectrometry. The scientists feed the mass spec data into a statistics computer program that distinguishes between healthy and cancerous tissues according to the types and amounts of phospholipids present. The team has integrated this technique with existing laser surgery instruments to analyze the aerosols produced as the laser excises tissue. In 2009, Takáts and coworkers reported an early version of the technique that used electrodes to ionize tissue molecules.