Table 2.

Rates of MSI and abnormal DNA MMR protein expression (MMR IHC) in Lynch syndrome–associated adenomas

Adenomas N = 37aMSI-H N = 15 (%)MSI-L/MSS N = 22 (%)Abnormal MMR IHC N = 18 (%)Intact MMR IHC N = 18 (%)
Subject sex
 Male (N = 15)7 (47)8 (53)8 (57)6 (43)
 Female (N = 22)8 (36)14 (64)10 (45)12 (55)
Subject age, y
 0–49 (N = 18)4 (22)14 (78)8 (44)10 (56)
 ≥50 (N = 19)11 (58)8 (42)10 (56)8 (44)
Germline MMR mutation
 MLH1 (N = 12)4 (33)8 (67)8 (67)4 (33)
 MSH2 (N = 21)10 (48)11 (52)10 (50)10 (50)
 MSH6 (N = 4)1 (25)3 (75)0 (0)4 (100)
Adenoma location
 Proximal (N = 16)6 (38)10 (63)7 (44)9 (56)
 Distal (N = 21)9 (43)12 (57)11 (55)9 (45)
Adenoma sizeb, mm
 <5 (N = 22)7 (32)15 (68)8 (38)13 (62)
 5–9 (N = 7)2 (29)5 (71)4 (57)3 (43)
 ≥10 (N = 6)6 (100)0 (0)6 (100)0 (0)

NOTE: All values are expressed as N (%).

  • aAll N values refer to number of adenomas.

  • bSize data were unknown for 2 MSS adenomas, both with intact immunohistochemistry.