Table 2.
Univariate analysis of the clinicopathologic features
| Variables | Wild type N = 927 (%) |
KRAS | KRAS exon 2 | KRAS exon 3 | KRAS exon 4 | ||||
|---|---|---|---|---|---|---|---|---|---|
| Mutant N = 889 (%) |
P-value | Mutant N = 780 (%) |
P-value | Mutant N = 34 (%) |
P-value | MutantN = 75 (%) | P-value | ||
| Sex | 0.001 | 0.003 | 0.020 | 0.379 | |||||
| Male | 591 (63.8) | 501 (56.4) | 442 (56.7) | 15 (44.1) | 44 (58.7) | ||||
| Female | 336 (36.2) | 388 (43.6) | 338 (43.3) | 19 (55.9) | 31 (41.3) | ||||
| Age | 60.0 (22-89) | 62.0 (20-91) | 0.003 | 62.0 (20-91) | 0.011 | 60.0 (37-90) | 0.749 | 64.0 (34-89) | 0.017 |
| Tumor site | 0.001 | 0.001 | 0.140 | 0.004 | |||||
| Rectum | 430 (46.4) | 429 (48.3) | 373 (47.8) | 12 (35.3) | 44 (58.7) | ||||
| Left | 321 (34.6) | 186 (20.9) | 164 (21.0) | 11 (32.4) | 11 (14.7) | ||||
| Right | 176 (19.0) | 274 (30.8) | 243 (31.2) | 11 (32.4) | 20 (26.6) | ||||
| Tumor size | 4.0 (0.5-17.0) | 4.2 (0.5-22.0) | 0.040 | 4.1 (0.5-22.0) | 0.089 | 3.9 (1.5-7.5) | 0.933 | 4.5 (1.2-11.0) | 0.014 |
| CEA level | 0.001 | 0.001 | 0.113 | 0.175 | |||||
| ≤5 μg/L | 520 (56.1) | 411 (46.2) | 361 (46.3) | 14 (41.2) | (48.0) | ||||
| >5 μg/L | 407 (43.9) | 478 (53.8) | 419 (53.7) | 20 (58.8) | 39 (52.0) | ||||
| T stage | 0.676 | 0.514 | 0.148 | 0.665 | |||||
| T1 | 31 (3.3) | 25 (2.8) | 21 (2.7) | 4 (5.3) | |||||
| T2 | 126 (13.6) | 107 (12.0) | 92 (11.8) | 3 (8.8) | 12 (16.0) | ||||
| T3 | 512 (55.2) | 506 (56.9) | 453 (58.1) | 16 (47.1) | 37 (49.4) | ||||
| T4 | 258 (27.9) | 251 (28.2) | 214 (27.4) | 15 (44.1) | 22 (29.3) | ||||
| N stage | 0.124 | 0.111 | 0.114 | 0.542 | |||||
| N0 | 399 (43.0) | 351 (39.5) | 306 (39.2) | 10 (29.4) | 35 (46.7) | ||||
| N1-2 | 528 (57.0) | 538 (60.5) | 474 (60.8) | 24 (70.6) | 40 (53.3) | ||||
| TNM stage | 0.002 | 0.001 | 0.057 | 0.588 | |||||
| I | 102 (11.0) | 74 (8.3) | 60 (7.7) | 2 (5.9) | 12 (16.0) | ||||
| II | 235 (25.4) | 206 (23.2) | 180 (23.1) | 7 (20.6) | 19 (25.4) | ||||
| III | 310 (33.4) | 280 (31.5) | 251 (32.2) | 9 (26.5) | 20 (26.6) | ||||
| IV | 280 (30.2) | 329 (37.0) | 289 (37.0) | 16 (47.0) | 24 (32.0) | ||||
| Histological | 0.001 | 0.001 | 0.596 | 0.003 | |||||
| Ulcer type | 662 (71.4) | 565 (63.6) | 495 (63.5) | 27 (79.4) | 43 (57.3) | ||||
| Tumor type | 225 (24.3) | 294 (33.1) | 257 (32.9) | 6 (17.6) | 31 (41.3) | ||||
| Invasive type | 40 (4.3) | 30 (3.3) | 28 (3.6) | 1 (3.0) | 1 (1.4) | ||||
| Pathology | 0.002 | 0.010 | 0.460 | 0.001 | |||||
| Adenocarcinoma | 851 (91.8) | 776 (87.3) | 687 (88.1) | 30 (88.2) | 59 (78.7) | ||||
| Mucinous | 76 (8.2) | 113 (12.7) | 93 (11.9) | 4 (11.8) | 16 (21.3) | ||||
| Differentiation | 0.023 | 0.092 | 0.157 | 0.011 | |||||
| G3-G4 | 252 (27.2) | 285 (32.1) | 241 (30.9) | 13 (38.2) | 31 (41.3) | ||||
| G1-G2 | 675 (72.8) | 604 (67.9) | 539 (69.1) | 21 (61.8) | 44 (58.7) | ||||
| Lymphovascular invasion | 0.811 | 0.990 | 0.447 | 0.095 | |||||
| Negative | 604 (65.2) | 584 (65.7) | 508 (65.1) | 20 (58.8) | 56 (74.7) | ||||
| Positive | 323 (34.8) | 305 (34.3) | 272 (34.9) | 14 (41.2) | 19 (25.3) | ||||
| Perineural invasion | 0.164 | 0.097 | 0.358 | 0.237 | |||||
| Negative | 618 (66.7) | 565 (63.6) | 490 (62.8) | 20 (58.8) | 55 (73.3) | ||||
| Positive | 309 (33.3) | 324 (36.4) | 290 (37.2) | 14 (41.2) | 20 (26.6) | ||||
| Extranodal tumor deposit | 0.011 | 0.013 | 0.024 | 0.878 | |||||
| Negative | 755 (81.4) | 681 (76.6) | 597 (76.5) | 22 (64.7) | 62 (82.7) | ||||
| Positive | 172 (18.6) | 208 (23.4) | 183 (23.5) | 12 (35.3) | 13 (17.3) | ||||