MLH1 and cancer: When the size of allelic changes was compared between IHC patterns in each cancer type (Supplemental Figure S3), there was a statistically significant difference between MLH1-/PMS2- and MSH2-/MSH6- for BAT-52 in colorectal cancer (P = 0.038) and for NR-27 in endometrial cancer (P = 0.011) (Fig. 2).