Method used to diagnose microsatellite instability and specific molecular aberrations
| Diagnostic method | C (n (%)) | CR (n (%)) | Total (n (%)) |
| IHC | 8 (47) | 9 (45) | 17 (46) |
| NGS | 6 (35) | 7 (35) | 13 (35) |
| IHC + NGS | 3 (18) | 4 (20) | 7 (19) |
| Specific molecular aberration | |||
| IHC | |||
| MLH-1 | 3 (17) | 5 (25) | 8 (22) |
| MSH-2 | 1 (6) | 2 (10) | 3 (8) |
| MSH-6 | 1 (6) | 2 (10) | 3 (8) |
| PMS-2 | 1 (6) | 0 (0) | 1 (3) |
| MSH-2 + MSH-6 | 2 (12) | 0 (0) | 2 (5) |
| NGS | |||
| MSI-high | 6 (35) | 7 (35) | 13 (35) |
| IHC + NGS | |||
| MSI-high + MLH-1 | 2 (12) | 2 (10) | 4 (11) |
| MSI-high + MSH-2 | 1 (6) | 1 (5) | 2 (5) |
| MSI-high + MSH-6 | 0 (0) | 1 (5) | 1 (3) |
C, chemotherapy-alone; CR, chemoradiation; IHC, immunohistochemistry; MSI, microsatellite instability; NGS, next-generation sequencing.