MSH6 and neoplasm: Of the 59 dMMR tumours, 79.7% (47/59) exhibited both MLH1 and PMS2 deficiency (dMLH1), 15.3% (9/59) exhibited both MSH2 and MSH6-deficiency (dMSH2), 5.1% (3/59) exhibited MSH6-deficiency alone (dMSH6), and none of the tumours displayed PMS2-deficiency on their own (dPMS2).