Table 1 Baseline characteristics of metachronous metastatic colorectal cancer patients by EGFR expression and KRAS mutation status
Characteristic | EGFR positive (%) | EGFR negative (%) | Pvalue | KRASWTa(%) | KRASMutb(%) | Pvalue |
|---|---|---|---|---|---|---|
N = 67 (79.8%) | N = 17 (20.2%) | N = 54 (55.1%) | N = 44 (44.9%) | |||
Age (years, mean ± SD) | 59.13 ± 10.49 | 64.41 ± 12.13 | 0.076 | 59.98 ± 10.21 | 59.18 ± 13.81 | 0.743 |
Gender | Â | Â | 0.547 | Â | Â | 0.011 |
Male | 37 (55.2) | 8 (47.1) | Â | 36 (66.7) | 18 (40.9) | Â |
Female | 30 (44.8) | 9 (52.9) | Â | 18 (33.3) | 26 (59.1) | Â |
Tumor size | Â | Â | 0.04 | Â | Â | 0.910 |
≥5 cm | 18 (26.9) | 9 (53.9) |  | 19 (35.2) | 15 (34.1) |  |
<5Â cm | 49 (73.1) | 8 (47.1) | Â | 35 (64.8) | 29 (65.9) | Â |
Tumor location | Â | Â | 0.518 | Â | Â | 0.130 |
Colon | 45 (67.2) | 10 (58.8) | Â | 30 (49.2) | 31 (34.0) | Â |
Rectum | 22 (32.8) | 7 (41.2) | Â | 24 (64.9) | 13 (66.0) | Â |
Histology | Â | Â | 0.044 | Â | Â | 0.688 |
Well | 1 (2.5) | 1 (5.9) | Â | 1 (1.9) | 1 (2.3) | Â |
Moderately | 62 (92.5) | 12 (70.6) | Â | 45 (83.3) | 39 (88.6) | Â |
Poorly | 4 (5.0) | 4 (23.5) | Â | 8 (14.8) | 4 (9.1) | Â |
Histology | Â | Â | 0.028 | Â | Â | 0.390 |
Well + Moderately | 63 (94.0) | 13 (76.5) |  | 46 (85.2) | 40 (90.9) |  |
Poorly | 4 (6.0) | 4 (23.5) | Â | 8 (14.8) | 4 (9.1) | Â |
AJCC stage (Initial diagnosis) | Â | Â | 0.928 | Â | Â | 0.993 |
I | 6 (9.0) | 2 (11.8) | Â | 5 (9.3) | 4 (9.1) | Â |
II | 19 (28.4) | 5 (29.4) | Â | 14 (25.9) | 11 (25.0) | Â |
III | 42 (62.6) | 10 (58.8) | Â | 35 (64.8) | 29 (65.9) | Â |
Tumor depth | Â | Â | 0.531 | Â | Â | 0.344 |
T1 | 0 (0) | 0 (0) | Â | 1 (1.9) | 0 (0.0) | Â |
T2 | 8 (11.9) | 2 (11.8) | Â | 4 (7.4) | 6 (13.6) | Â |
T3 | 48 (71.7) | 14 (82.3) | Â | 39 (72.2) | 34 (77.3) | Â |
T4 | 11 (16.4) | 1 (5.9) | Â | 10 (18.5) | 4 (9.1) | Â |
Lymph nodes metastases | Â | Â | 0.755 | Â | Â | 0.401 |
N0 | 25 (37.3) | 7 (41.2) | Â | 19 (35.2) | 15 (34.1) | Â |
N1 | 30 (44.8) | 6 (35.3) | Â | 21 (38.9) | 22 (50.0) | Â |
N2 | 12 (17.9) | 4 (23.5) | Â | 14 (25.9) | 7 (15.9) | Â |
Retrived LN c | 14.50 ± 8.70 | 16.00 ± 7.18 | 0.594 | 14.98 ± 9.98 | 15.69 ± 9.26 | 0.742 |
Vascular invasion | Â | Â | 0.701 | Â | Â | 0.053 |
Yes | 23 (34.3) | 5 (29.4) | Â | 25 (46.3) | 12 (27.3) | Â |
No | 44 (65.75) | 12 (70.6) | Â | 29 (53.7) | 32 (72.7) | Â |
Perineurial invasion | Â | Â | 0.395 | Â | Â | 0.624 |
Yes | 23 (34.3) | 4 (23.5) | Â | 21 (38.9) | 15 (34.1) | Â |
No | 44 (65.75) | 13 (76.5) | Â | 33 (61.1) | 29 (65.9) | Â |
Pre-op serum CEA level | Â | Â | 0.598 | Â | Â | 0.482 |
≥5 ng/ml | 27 (40.3) | 7 (41.2) |  | 24 (44.4) | 21 (47.7) |  |
<5Â ng/ml | 40 (59.7) | 10 (58.8) | Â | 30 (55.6) | 23 (52.3) | Â |
Post-op serum CEA level | Â | Â | 0.356 | Â | Â | 0.097 |
≥5 ng/ml | 21 (31.3) | 4 (23.5) |  | 20 (37.0) | 10 (22.7) |  |
<5Â ng/ml | 46 (68.7) | 13 (76.5) | Â | 34 (63.0) | 34 (77.3) | Â |
Overall survival (months) | 36.72 ± 18.68 | 62.51 ± 31.86 | <0.001 | 42.54 ± 28.07 | 37.41 ± 17.23 | 0.293 |
Disease-free survival (months) | 14.48 ± 9.91 | 34.27 ± 18.58 | <0.001 | 18.38 ± 15.86 | 16.43 ± 10.58 | 0.487 |