Table 1 Clinicopathological characteristics of patients receiving open or laparoscopic surgery
Characteristics | No. | Operation type | χ2/t value | P value | |
|---|---|---|---|---|---|
| Â | Â | Open (N = 92) | Laparoscopic (N = 90) | Â | Â |
Age |  | 57.45 ± 10.43 | 58.07 ± 13.37 | − 0.350 | 0.727 |
 ≤ 60years | 107 (58.8%) | 57 (62.0%) | 50 (55.6%) | 0.769 | 0.380 |
 > 60years | 75 (41.2%) | 35 (38.0%) | 40 (44.4%) |  |  |
Gender | |||||
 Male | 134 (73.6%) | 70 (76.1%) | 64 (71.1%) | 0.580 | 0.446 |
 Female | 48 (26.4%) | 22 (23.9%) | 26 (28.9%) |  |  |
Tumor size | |||||
 ≤ 5 cm | 132 (72.5%) | 70 (76.1%) | 62 (68.9%) | 1.183 | 0.277 |
 > 5 cm | 50 (27.5%) | 22 (23.9%) | 28 (31.1%) |  |  |
Borrmann classification | |||||
 I+II | 69 (37.9%) | 34 (37.0%) | 35 (38.9%) | 0.072 | 0.788 |
 III+IV | 113 (62.1%) | 58 (63.0%) | 55 (61.1%) |  |  |
Histological differentiation | |||||
 Well | 5 (2.8%) | 3 (3.3%) | 2 (2.2%) | 1.459 | 0.482 |
 Moderate | 49 (26.9%) | 28 (30.4%) | 21 (23.3%) |  |  |
 Poor | 128 (70.3%) | 61 (66.3%) | 67 (74.5%) |  |  |
Vascular invasion | |||||
 No | 152 (83.5%) | 76 (82.6%) | 76 (84.4%) | 0.111 | 0.739 |
 Yes | 30 (16.5%) | 16 (17.4%) | 14 (15.6%) |  |  |
Nerve invasion | |||||
 No | 167 (91.8%) | 81 (88.0%) | 86 (95.6%) | 3.395 | 0.065 |
 Yes | 15 (8.2%) | 11 (12.0%) | 4 (4.4%) |  |  |
Depth of invasion | |||||
 T1 | 29 (15.9%) | 14 (15.2%) | 15 (16.7%) | 4.154 | 0.386 |
 T2 | 24 (13.2%) | 11 (12.0%) | 13 (14.4%) |  |  |
 T3 | 70 (38.5%) | 31 (33.7%) | 39 (43.3%) |  |  |
 T4a | 38 (20.9%) | 24 (26.1%) | 14 (15.6%) |  |  |
 T4b | 21 (11.5%) | 12 (13.0%) | 9 (10.0%) |  |  |
Lymph node metastasis | |||||
 N0 | 73 (40.1%) | 35 (38.0%) | 38 (42.2%) | 0.859 | 0.930 |
 N1 | 34 (18.7%) | 17 (18.5%) | 17 (18.9%) |  |  |
 N2a | 33 (18.1%) | 19 (20.7%) | 14 (15.6%) |  |  |
 N2b | 24 (13.2%) | 12 (13.0%) | 12 (13.3%) |  |  |
 N3 | 18 (9.9%) | 9 (9.8%) | 9 (10.0%) |  |  |
pTNM | |||||
 I | 43 (23.6%) | 21 (22.8%) | 22 (24.4%) | 2.081 | 0.353 |
 II | 57 (31.3%) | 25 (27.2%) | 32 (35.6%) |  |  |
 III | 82 (45.1%) | 46 (50.0%) | 36 (40.0%) |  |  |
CEA level(μg/L) | |||||
 ≤ 5 | 160 (87.9%) | 74 (80.4%) | 86 (95.6%) | 9.788 | 0.002 |
 > 5 | 22 (12.1%) | 18 (19.6%) | 4 (4.4%) |  |  |
Resection range | |||||
 Proximal | 2 (1.1%) | 2 (2.2%) | 0 (0%) | 3.403 | 0.182 |
 Distal | 94 (51.6%) | 43 (46.7%) | 51 (56.7%) |  |  |
 Total | 86 (47.3%) | 47 (51.1%) | 39 (43.3%) |  |  |
Lymphadenectomy | |||||
 D2 | 158 (86.8%) | 79 (85.9%) | 79 (87.8%) | 0.145 | 0.704 |
 D2+ | 24 (13.2%) | 13 (14.1%) | 11 (12.2%) |  |  |
NORLN |  | 33.73 ± 17.32 | 31.29 ± 13.89 | 1.047 | 0.297 |
NOMLN |  | 5.03 ± 8.50 | 4.83 ± 8.56 | 0.158 | 0.875 |
PHS (days) |  | 11.97 ± 6.76 | 9.14 ± 2.45 | 3.728 | 0.000 |
Operation time (min) |  | 249.87 ± 48.79 | 307.85 ± 64.99 | 6.795 | 0.000 |