Table 1. Demographic characteristics, clinical features, and allele distributions of study patients.
| Total | Colon | Rectum | ||
| Variablesa | N (%) | N (%) | N (%) | P |
| Ageb (y) | 58.5±12.5 | 57.1±12.9 | 60.4±11.6 | 0.004c |
| Sex | 0.105d | |||
| Male | 260 (52.9) | 141 (49.8) | 119 (57.2) | |
| Female | 231 (47.1) | 142 (50.2) | 89 (42.8) | |
| Family history of cancer | 0.961d | |||
| No | 305 (64.5) | 175 (64.6) | 130 (64.4) | |
| Yes | 168 (35.5) | 96 (35.4) | 72 (35.6) | |
| Multiplicity | 0.029d | |||
| No | 467 (95.1) | 264 (93.3) | 203 (97.6) | |
| Yes | 24 (4.9) | 19 (6.7) | 5 (2.4) | |
| Histological differentiation | 0.009d | |||
| Well | 59 (12.1) | 38 (13.6) | 21 (10.1) | |
| Moderately | 382 (78.4) | 207 (73.9) | 175 (84.5) | |
| Poorly | 46 (9.5) | 35 (12.5) | 11 (5.4) | |
| Carcinoembryonic antigen | 0.086d | |||
| <5 ng/mL | 219 (46.4) | 117 (43.0) | 102 (51.0) | |
| ≥5 ng/mL | 253 (53.6) | 155 (57.0) | 98 (49.0) | |
| TNM stage | 0.001d | |||
| II | 74 (15.1) | 56 (19.8) | 18 (8.7) | |
| III | 267 (54.4) | 138 (48.8) | 129 (62.0) | |
| IV | 150 (30.5) | 89 (31.4) | 61 (29.3) | |
| GSTM1 | 0.254d | |||
| Null | 286 (58.2) | 171 (60.4) | 115 (55.3) | |
| Present | 205 (41.8) | 112 (39.6) | 93 (44.7) | |
| GSTT1 | 0.317d | |||
| Null | 249 (50.7) | 149 (52.6) | 100 (48.1) | |
| Present | 242 (49.3) | 134 (47.4) | 108 (51.9) | |
| GSTP1 Ile105Val | 0.632d | |||
| Ile/Ile | 336 (68.4) | 191 (67.5) | 145 (69.7) | |
| Ile/Val | 139 (28.3) | 81 (28.6) | 58 (27.9) | |
| Val/Val | 16 (3.3) | 11 (3.9) | 5 (2.4) | |
| XRCC1 Arg399Gln | 0.016d | |||
| Arg/Arg | 249 (50.7) | 159 (56.2) | 90 (43.3) | |
| Arg/Gln | 212 (43.2) | 110 (38.9) | 102 (49.0) | |
| Gln/Gln | 30 (6.1) | 14 (5.0) | 16 (7.7) | |
| XRCC3 Thr241Met | 0.565e | |||
| Thr/Thr | 459 (93.5) | 263 (92.9) | 196 (94.2) | |
| Thr/Met | 32 (6.5) | 20 (7.1) | 12 (5.8) | |
| Met/Met | 0 (0.0) | 0 (0.0) | 0 (0.0) | |
| XPD Lys751Gln | 0.327e | |||
| Lys/Lys | 404 (82.3) | 234 (82.7) | 170 (81.7) | |
| Lys/Gln | 84 (17.1) | 46 (16.2) | 38 (18.3) | |
| Gln/Gln | 3 (0.6) | 3 (1.1) | 0 (0.0) | |
a
Sum may not be equal to the total number (N) because of missing data.
b
Mean±standard deviation.
c
Student t-test.
d
Chi-squared test.
e
Fisher exact test.
TNM: tumor-node-metastasis.