Pang J, et al. - Researchers intended to develop a method to distinguish microsatellite instability (MSI) that would not require paired normal tissue and would leverage the sequence data obtained from a broad range of tumors tested using the 467-gene NGS Columbia Combined Cancer Panel (CCCP). They analyzed revised mononucleotide and dinucleotide microsatellite loci across the CCCP region of interest in clinical samples encompassing a diverse range of tumour types. They applied the number of altered loci to develop a decision tree classifier model trained on the retrospectively collected cohort of 107 clinical cases sequenced by the CCCP assay. This research indicates the benefit of this approach, which should apply to laboratories performing similar testing.