Table 1 Patient characteristics (N = 143) and the association between KRAS mutational status and clinicopathologic parameters
Characteristic | No. of patients | |||
|---|---|---|---|---|
| Â | All | KRAS WT | KRAS MT | P-value |
| Â | N | N (%) | N (%) | Â |
Gender | Â | Â | Â | 0.897 |
 Male | 77 | 37 (54.4) | 40 (53.3) |  |
 Female | 66 | 31 (45.6) | 35 (46.7) |  |
Age | Â | Â | Â | 0.303 |
 < 65 years | 97 | 49 (72.1) | 48 (64.0) |  |
 ≥ 65 years | 46 | 19 (27.9) | 27 (36.0) |  |
Clinical situations for the development of systemic metastasis | Â | Â | Â | 0.010 |
 Stage IV at the time of initial diagnosis | 101 | 55 (80.9) | 46 (61.3) |  |
 Recurred after curative resection | 42 | 13 (19.1) | 29 (38.7) |  |
Primary site | Â | Â | Â | 0.802 |
 Colon | 108 | 52 (76.5) | 56 (74.7) |  |
 Rectum | 35 | 16 (23.5) | 19 (25.3) |  |
Histology and grade | Â | Â | Â | 0.819 |
 ADC, well differentiated | 5 | 2 (2.9) | 3 (4.0) |  |
 ADC, moderately differentiated | 118 | 56 (82.4) | 62 (82.7) |  |
 ADC, poorly differentiated | 12 | 7 (10.3) | 5 (6.7) |  |
 ADC, mucinous | 8 | 3 (4.4) | 5 (6.7) |  |
Gross morphology of primary tumor | Â | Â | Â | 0.421 |
 Ulceroinfiltrative | 66 | 33 (48.5) | 33 (44.0) |  |
 Ulcerofungating | 63 | 28 (41.2) | 35 (46.7) |  |
 Polypoid | 7 | 2 (2.9) | 5 (6.7) |  |
 Unknown | 7 | 5 (7.4) | 2 (2.7) |  |
Obstruction of primary tumor | Â | Â | Â | 0.371 |
 Yes | 43 | 18 (26.5) | 25 (33.3) |  |
 No | 100 | 50 (73.5) | 50 (66.7) |  |
Perforation of primary tumor | Â | Â | Â | 1.000 |
 Yes | 10 | 5 (7.4) | 5 (6.7) |  |
 No | 133 | 63 (92.6) | 70 (93.3) |  |
Microsatellite instability | Â | Â | Â | 0.343 |
 Stable | 121 | 58 (85.3) | 63 (84.0) |  |
 Low frequency | 11 | 3 (4.4) | 8 (10.7) |  |
 High frequency | 2 | 1 (1.5) | 1 (1.3) |  |
 Unknown | 9 | 6 (8.8) | 3 (4.0) |  |