Imaging mass spectrometry in clinical pathology

Several decades ago, researchers demonstrated the concept of acquiring molecular images directly from human tissue using a mass spectrometer. Since that time, pioneering research has developed imaging mass spectrometry (IMS) technologies, resulting in commercially available imaging capabilities for various mass analyzers and ionization sources. Matrix-assisted laser desorption/ionization (MALDI) IMS is an established technology well suited for clinical and biological applications as it can determine the in situ localization and distribution of small molecules, drugs, lipids, peptides, and low and high molecular weight proteins without prior knowledge of their presence in a tissue sample. In addition, this technology provides precise molecular information that describes disease state and progression, therapeutic efficacy, disease biomarkers, molecular tumor margins, and molecular mechanisms of disease. This chapter reviews the clinical utility of MALDI IMS and discusses applications to diabetes and cancer. Lastly, we describe recent technological advances in IMS that will impact future clinical applications. Current developments in the field aim to improve throughput and facilitate clinicians’ use of the technology to improve patient outcomes.