Table 1.
Clinical and molecular features of MMR-D colon cancer in relation to the etiology of MSI-H.
| Characteristic | No. of patients (%) |
P value | Pairwise P values | ||
|---|---|---|---|---|---|
| HM-MSI (n = 103) | LS-MSI (n = 28) | DS-MSI (n = 17) | |||
|
| |||||
| Age, yearsa | 74 (43–89) | 48.5 (25–78) | 53 (28–89) | <0.0001 | <0.0001,b <0.0001,c 0.536d |
| Sex | |||||
| Female | 67 (65) | 9 (32) | 6 (35) | 0.002 | 0.002,b 0.017,c 0.933d |
| Male | 36 (35) | 19 (68) | 11 (65) | ||
| Tumor location | |||||
| Right colon | 94 (91) | 22 (79) | 12 (71) | 0.027 | 0.089,b 0.010,c 0.495d |
| Left colon | 9 (9) | 6 (21) | 5 (29) | ||
| Tumor grade | |||||
| Well/moderate | 64 (63) | 16 (59) | 13 (76) | 0.489 | |
| Poor | 37 (37) | 11 (41) | 4 (24) | ||
| LVI | |||||
| Present | 49 (48) | 11 (39) | 6 (35) | 0.497 | |
| Absent | 53 (52) | 17 (61) | 11 (65) | ||
| Stage | |||||
| I/II | 70 (68) | 22 (79) | 11 (65) | 0.500 | |
| III | 33 (32) | 6 (21) | 6 (35) | ||
| TIL level | |||||
| Low | 34 (33) | 9 (32) | 4 (24) | 0.738 | |
| High | 69 (67) | 19 (68) | 13 (76) | ||
| TMB, mt/Mba | 54 (20–112.3) | 68 (29–361.6) | 61 (36–134.3) | 0.057 | |
| No. of frameshiftsa | |||||
| Deletions | 15 (2–37) | 13.5 (1–38) | 19 (6–39) | 0.320 | |
| Insertions | 4 (0–15) | 4 (2–19) | 3 (0–14) | 0.125 | |
| MSIsensor scorea | 36 (10–50.5) | 32 (10–51) | 34 (18–52) | 0.221 | |
Abbreviations: DS, double somatic; HM; MMR-D, mismatch repair deficient; hypermethylation; LS, Lynch syndrome; LVI, lymphovascular invasion; MSI-H, microsatellite instability-high; TIL, tumor-infiltrating lymphocytes; TMB, tumor mutational burden.
a
Median (range)
b
HM-MSI vs LS-MSI
c
HM-MSI vs DS-MSI
d
LS-MSI vs DS-MSI