Abstract: The use of matrix-assisted laser desorption ionization (MALDI) mass spectrometry imaging (MSI) to assay feline tissue samples is described. Methods of analyzing a tissue sample may generally comprise generating sample ions directly from the tissue sample using a MALDI ionization source, receiving the ions into a mass spectrometer, identifying at least one inflammatory bowel disease and/or lymphoma related compound in the sample from results from the mass spectrometer, comparing the at least one identified related compound in the sample to one or more known inflammatory bowel disease and/or lymphoma profiles, and identifying at least one condition related to the sample from the comparison of the at least one identified related compound to the one or more known inflammatory bowel disease and/or lymphoma profiles. The mass spectrometer may be a quadrupole mass spectrometer, a time of flight mass spectrometer, an Orbitrap mass spectrometer, or an ion trap mass spectrometer.