Mass spectrometry imaging (MSI) combines the excellence in molecular characterization of mass spectrometry with microscopic imaging capabilities of hematoxylin- and eosin-stained samples, enabling the precise location of several analytes in the tissue. Especially in the field of pathology, MSI may have an impactful role in tumor diagnosis, biomarker identification, prognostic prediction, and characterization of tumor margins during tumor resection procedures. This article discusses the recent developments in the field that are paving the way for this technology to become accepted as an analytical tool in the clinical setting, its current limitations, and future directions.
Mass spectrometry imaging (MSI) is a versatile technique capable of mapping the precise location of analyte molecules in tissue samples.
MSI has been applied in different areas of histomorphological characterization of tumor lesions, such as biomarker identification, tumor diagnosis, and delineation of tumor margins.
Reproducibility, validation, data analysis, and data storage are the main barriers to the establishment of the methodology in routine clinical care.
To treat any condition, the first step should be an unambiguous and precise diagnosis. Especially in cancer therapy, the diagnosis is essential to suggest the more appropriate course of treatment. In pathology, a myriad of tests and technologies is applied to assist a better diagnosis. However, there are still several tests that are ambiguous, time-consuming, and expensive. Some of those techniques resort to proteomics to unveil specific features of a heterogenic set of pathologies.
Because of its high sensitivity and specificity, mass spectrometry was granted the status of the method of choice for analysis of proteins, peptides, and metabolites. Mass spectrometry, in particular, liquid chromatography-mass spectrometry (LC-MS), has been introduced to identify proteomic derivatives that can elucidate the tumor microenvironment. However, the limitations of this technique (low spatial resolution and heavy sample processing) are being overcome by mass spectrometry imaging (MSI).