Cost-effective screening using a two-antibody panel for detecting mismatch repair deficiency in sporadic colorectal cancer

Table 2 Immunohistochemistry patterns (n = 3486)

Expression patterns	n (%)
Retained expression of 4 proteins	3285 (94.2)
Loss of at least 1 protein	201 (5.8)
Loss of PMS2	136 (3.9)
Loss of MLH1	133 (3.8)
Loss of MSH6	58 (1.7)
Loss of MSH2	49 (1.4)
Concurrent loss of MLH1 and PMS2	126 (3.6)
Loss of PMS2 alone	10 (0.3)
Loss of MLH1 alone	7 (0.2)
Concurrent loss of MSH2 and MSH6	43 (1.2)
Loss of MSH6 alone	15 (0.4)
Loss of MSH2 alone	6 (0.2)