Table 1 Mismatch repair protein immunohistochemical staining pattern of study cases

From: A two-antibody mismatch repair protein immunohistochemistry screening approach for colorectal carcinomas, skin sebaceous tumors, and gynecologic tract carcinomas

Immunohistochemical pattern (no., %)

Retrospective group (no., %)

Prospective group (no., %)

Total (n=432)

 

Colorectal carcinoma (n=260)

Sebaceous tumor (n=42)

Gynecologic carcinoma (n=26)

Other carcinoma (n=6)

Colorectal carcinoma (n=63)

Sebaceous tumor (n=7)

Gynecologic carcinoma (n=24)

Other carcinoma (n=4)

 

Loss of at least 1 protein

54 (21)

23 (55)

14 (54)

0 (0)

5 (8)

1 (14)

5 (21)

0 (0)

102 (24)

Loss of MLH1 and PMS2

31 (12)

6 (14)

7 (27)

0 (0)

3 (5)

0 (0)

3 (13)

0 (0)

50 (12)

Loss of MLH1 alone

0 (0)

0 (0)

0 (0)

0 (0)

0 (0)

0 (0)

0 (0)

0 (0)

0 (0)

Loss of PMS2 alone

4 (2)

0 (0)

0 (0)

0 (0)

1 (2)

0 (0)

0 (0)

0 (0)

5 (1)

Loss of MSH2 and MSH6

12 (5)

16 (38)

4 (15)

0 (0)

0 (0)

1 (14)

0 (0)

0 (0)

33 (8)

Loss of MSH2 alone

0 (0)

0 (0)

0 (0)

0 (0)

0 (0)

0 (0)

0 (0)

0 (0)

0 (0)

Loss of MSH6 alone

7 (3)

1 (2)

3 (12)

0 (0)

1 (2)

0 (0)

2 (8)

0 (0)

14 (3)

Equivocal resultsa

0 (0)

1 (2) (MSH6)

0 (0)

0 (0)

0 (0)

1 (14) (MSH6)

2 (8) (MSH6)

1 (25) (MSH6)

5 (1)

All proteins tested intact

206 (79)

18 (43)

12 (46)

6 (100)

58 (92)

5 (71)

17 (71)

3 (75)

325 (75)

  1. aAntibodies yielding equivocal immunohistochemical staining listed in parentheses.