Table 2.
Clinical characteristics of patients with unusual and classical MMR-D tumors.
| Characteristics | Unusual MMR-D (n = 89) | Typical MMR-D (n = 496) | p |
|---|---|---|---|
| Mean age at diagnosis (years) | 57.5 | 59.7 | 0.15 |
| Gender (%) | |||
| Female | 57.3 (n = 51) | 56 (n = 278) | 0.83 |
| Male | 43.7 (n = 38) | 44 (n = 218) | – |
| Histological type (%) | |||
| Colorectal carcinoma | 67.4 (n = 60) | 86.9 (n = 431) | <0.001 |
| Non-colorectal GI carcinoma | 9 (n = 8) | 3.6 (n = 18) | – |
| Endometrial carcinoma | 11.2 (n = 10) | 6.5 (n = 32) | – |
| Other tumors | 12.4 (n = 11) | 3 (n = 15) | – |
| Stage at diagnosis (%) | |||
| 0 to III | 85.4 (n = 76) | 81 (n = 402) | 0.74 |
| IV | 12.4 (n = 11) | 15.7 (n = 78) | – |
| Missing data | 2.2 (n = 2) | 3.2 (n = 16) | – |
| Genetic investigation (%) | |||
| Yes | 60.7 (n = 54) | 52.8 (n = 262) | 0.17 |
| No | 39.3 (n = 35) | 47.2 (n = 234) | – |
| Genetic syndrome identified (%) | |||
| Yes | 44.9 (n = 40) | 21.4 (n = 106) | <0.001 |
| Lynch Syndrome | 42.7 (n = 38) | 21.4 (n = 106) | – |
| POLE | 1.1 (n = 1) | 0 | – |
| CMMR-D | 1.1 (n = 1) | 0 | – |
| No | 55.1 (n = 49) | 78.6 (n = 390) | |
| Genetic syndrome identified among patients investigated (%) | |||
| Yes | 74.1 (n = 40) | 40.5 (n = 106) | <0.001 |
| No | 25.9 (n = 14) | 59.5 (n = 156) | – |
GI gastrointestinal, POLE polymerase E deficiency syndrome, CMMR-D constitutional mismatch repair deficiency.
Other tumors included: for the 11 unusual MMR-D: 6 sebaceous tumors, 1 urothelial carcinoma, 1 glioblastoma, 2 ovarian carcinomas and 1 sarcoma and for the 15 classical MMR-D: 6 sebaceous tumors, 3 urothelial carcinomas, 1 melanoma, 4 ovarian carcinomas and 1 neuroendocrine tumor.