Table 3.
Concordance and discordance between microsatellite instability (MSI) and immunohistochemistry (IHC) results in endometrial adenocarcinomas.
| Number | % | (95% CI) | |
|---|---|---|---|
| MSI-High | |||
| IHC shows loss of expression of at least one MMR protein | 49 | 98.0 | (89.4 – 99.9) |
| IHC shows intact expression of all 4 proteins | 1 | 2.0 | (0.0 – 10.6) |
| MSI-Stable | |||
| IHC shows loss of expression of at least one MMR protein | 5 | 3.5 | (1.2 – 8.0) |
| IHC shows intact expression of all 4 proteins | 137 | 96.5 | (92.0 – 98.8) |
| IHC loss of at least one MMR protein | |||
| MSI-Low | 1 | 1.8 | (0.0 – 9.7) |
| MSI-Stable | 5 | 9.1 | (3.0 – 20.0) |
| MSI-High | 49 | 89.1 | (77.8 – 95.9) |
| IHC shows intact expression of all 4 proteins | |||
| MS-Low | 4 | 2.8 | (0.8 – 7.1) |
| MS-Stable | 137 | 96.5 | (92.0 – 98.8) |
| MS-High | 1 | 0.7 | (0.0 – 3.9) |
| Overall Agreement | |||
| Concordance1 | 186 | 96.9 | (93.3 – 98.8) |
| Discordance2 | 6 | 3.1 | (1.2 – 6.7) |
1
IHC shows loss of expression of at least one MMR protein and MSI-High or IHC shows intact expression of all 4 proteins and MS-Stable
2
IHC shows loss of expression of at least one MMR protein and MS-Stable or IHC shows intact expression of all 4 proteins and MSI-High