In order to identify and compare the number of tumour-specific or enriched metabolites that could be detected with MALDI-2 as opposed to conventional MALDI, a co-localisation analysis was applied. Briefly, the tumour-bearing area of the liver metastasis was defined and guided via histology to determine the region-of-interest (ROI) and co-registration of the MSI data using LipostarMSI. From here, a list of m/z values having Pearson correlation coefficients with the tumour ROI ≥0.6 were extracted.