TABLE 1.
Baseline characteristics of mismatch repair gene mutation carriers included in the study
| All (n = 79) No. (%) |
Anterior resection (n = 50) |
Abdominoperineal resection (n = 29) |
|||
|---|---|---|---|---|---|
| No metachronous cancer (n = 37) No. (%) |
Metachronous cancer (n = 13) No. (%) |
No metachronous cancer (n = 21) No. (%) |
Metachronous cancer (n = 8) No. (%) |
||
| Sex, female | 44 (56) | 21 (57) | 8 (62) | 12 (57) | 3 (38) |
| Country | |||||
| Australia and New Zealand | 38 (48) | 22 (60) | 6 (46) | 7 (33) | 3 (37.5) |
| Canada | 11 (14) | 3 (8) | 2 (15) | 4 (19) | 2 (25) |
| United States | 30 (38) | 12 (32) | 5 (39) | 10 (48) | 3 (37.5) |
| MMR gene mutated | |||||
| MLH1 | 18 (23) | 8 (22) | 3 (23) | 5 (24) | 2 (25) |
| MSH2 | 55 (70) | 25 (67) | 10 (77) | 14 (66) | 6 (75) |
| MSH6 | 4 (5) | 3 (8) | 0 (0) | 1 (5) | 0 (0) |
| PMS2 | 2 (2) | 1 (3) | 0 (0) | 1 (5) | 0 (0) |
| Index rectal cancer | |||||
| Age at diagnosis (years), mean (SD) | 42.8 (10.5) | 43.3 (10.7) | 38.4 (12.5) | 44.3 (9.5) | 44.1 (8.8) |
| Length of bowel removed (cm), mean (SD) | 22.2 (8.0) | 20.8 (7.5) | 17.9 (6.8) | 26.9 (8.3) | 25.0 (6.2) |
| AJCC stage of tumora | |||||
| I | 28 (38) | 12 (35) | 4 (36) | 8 (38) | 4 (57) |
| II (A, B, C) | 33 (45) | 17 (50) | 3 (27) | 11 (52) | 2 (29) |
| III (A, B, C) | 12 (16) | 5 (15) | 4 (36) | 2 (10) | 1 (14) |
| Unknown | 6 | 3 | 2 | 0 | 1 |
| Histological grade | |||||
| Well | 6 (9) | 3 (9) | 1 (9) | 2 (11) | 0 (0) |
| Moderately | 44 (62) | 22 (65) | 5 (45) | 13 (68) | 4 (57) |
| Poorly | 18 (25) | 8 (23) | 3 (27) | 4 (21) | 3 (43) |
| Mucinous | 3 (4) | 1 (3) | 2 (18) | 0 (0) | 0 (0) |
| Unknown | 8 | 3 | 2 | 2 | 1 |
| Synchronous tumor | |||||
| Absent | 73 (96) | 35 (95) | 11 (100) | 21 (100) | 6 (86) |
| Present | 3 (4) | 2 (5) | 0 (0) | 0 (0) | 1 (14) |
| Unknown | 3 | 0 | 2 | 0 | 1 |
AJCC American Joint Committee on Cancer
a
Metastasis status was unavailable; and any of this stage could be stage IV