Imaging mass spectrometry: challenges in visualization of drug distribution in solid tumors

Mass spectrometry imaging (MSI) is an emerging technique that allows molecular visualization of the distribution of drugs and metabolites in a two-dimensional space directly in biological tissues. Imaging drug distribution inside a tumor is an important tool to support strategies to improve penetration of anticancer drugs and consequently the outcome of chemotherapy. MSI has some advantages in comparison to other imaging techniques, that is, whole body autoradiography, positron emission tomography or microscopy imaging. It is a label-free technique with better specificity and provides the possibility to combine histological data with MS ones and to visualize simultaneously the distribution of biomarkers in relation to tumor heterogeneity. We overview here publications on MSI applied to studies of the distribution of anticancer agents in tumor tissue. In addition, we focused our attention on technical limitations and future perspectives pertaining to this technique.