Table 1 Baseline characteristics of high ligation and low ligation groups (before and after PSM)
Before matching | After matching | ||||||
|---|---|---|---|---|---|---|---|
High ligation (n = 577) | Low ligation (n = 317) | p value | High ligation (n = 245) | Low ligation (n = 245) | SMD | p value | |
Age | 62.93 ± 12.13 | 64.91 ± 11.97 | 0.625 | 64.84 ± 11.43 | 64.14 ± 11.90 | 0.059 | 0.600 |
Gender | |||||||
Male | 333 (57.7%) | 182 (57.4%) | 0.931 | 141 (57.6%) | 144 (58.8%) | 0.024 | 0.784 |
Female | 244 (42.3%) | 135 (42.6%) | 104 (42.4%) | 101 (41.2%) | |||
BMI | |||||||
< 25 | 336 (58.2%) | 184 (58.0%) | 0.957 | 144 (58.8%) | 146 (59.6%) | 0.016 | 0.854 |
≥ 25 | 241 (41.8%) | 133 (42.0%) | 101 (41.2%) | 99 (40.4%) | |||
ASA class | |||||||
1 | 93 (16.1%) | 60 (18.9%) | 0.548 | 35 (14.3%) | 43 (17.6%) | 0.053 | 0.557 |
2 | 388 (67.3%) | 204 (64.4%) | 171 (69.8%) | 161 (65.7%) | |||
3 | 96 (16.6%) | 53 (16.7%) | 39 (15.9%) | 41 (16.7%) | |||
Medical illness (CVD, DM) | 271 (47.0%) | 156 (49.2%) | 0.520 | 118 (48.2%) | 119 (48.6%) | 0.008 | 0.928 |
Neoadjuvant therapy | 20 (3.5%) | 17 (5.4%) | 0.173 | 12 (4.9%) | 12 (4.9%) | 0 | 1.000 |
Pre-operative laboratory data | |||||||
CEA | |||||||
< 5 ng/mL | 436 (75.6%) | 269 (84.9%) | 0.001 | 209 (85.3%) | 203 (82.9%) | 0.066 | 0.459 |
≥ 5 ng/mL | 141 (24.4%) | 48 (15.1%) | 36 (14.7%) | 42 (17.1%) | |||
Albumin | |||||||
< 3.5 g/dL | 23 (4.0%) | 7 (2.2%) | 0.158 | 5 (2.0%) | 4 (1.6%) | 0.030 | 0.737 |
≥ 3.5 g/dL | 554 (96%) | 310 (97.8%) | 240 (98.0%) | 241 (98.4%) | |||
Tumor location | |||||||
Sigmoid | 346 (60.0%) | 140 (44.1%) | < 0.001 | 117 (47.8%) | 120 (49.0%) | 0.067 | 0.457 |
Upper rectum | 78 (13.5%) | 45 (14.2%) | 41 (16.7%) | 36 (14.7%) | |||
Middle rectum | 131 (22.7%) | 114 (36.0%) | 69 (28.2%) | 78 (31.8%) | |||
Lower rectum | 22 (3.8%) | 18 (5.7%) | 18 (7.3%) | 11 (4.5%) | |||
Tumor length | 3.63 ± 4.33 | 3.22 ± 7.80 | 0.264 | 3.41 ± 6.36 | 3.13 ± 6.35 | 0.044 | 0.835 |
T stage | |||||||
0 | 6 (1.0%) | 12 (3.8%) | < 0.001 | 4 (1.6%) | 5 (2.0%) | 0.073 | 0.415 |
1 | 69 (12.0%) | 95 (30.0%) | 53 (21.6%) | 63 (25.7%) | |||
2 | 106 (18.4%) | 59 (18.6%) | 61 (24.9%) | 44 (18.0%) | |||
3 | 299 (51.8%) | 136 (42.9%) | 114 (46.5%) | 118 (48.2%) | |||
4 | 97 (16.8%) | 15 (4.7%) | 13 (5.3%) | 15 (6.1%) | |||
N stage | |||||||
0 | 317 (54.9%) | 205 (64.7%) | 0.018 | 148 (60.4%) | 149 (60.8%) | 0.004 | 0.964 |
1 | 177 (30.7%) | 77 (24.3%) | 64 (26.1%) | 65 (26.5%) | |||
2 | 83 (14.4%) | 35 (11.0%) | 33 (13.5%) | 31 (12.7%) | |||
TNM stage | |||||||
0 | 5 (0.9%) | 12 (3.8%) | < 0.001 | 4 (1.6%) | 5 (2.0%) | 0.013 | 0.885 |
1 | 134 (23.2%) | 135 (42.6%) | 87 (35.5%) | 93 (38.0%) | |||
2 | 178 (30.8%) | 58 (18.3%) | 57 (23.3%) | 51 (20.8%) | |||
3 | 260 (45.1%) | 112 (35.3%) | 97 (39.6%) | 96 (39.2%) | |||
Operative method | |||||||
Open | 91 (15.8%) | 21 (6.6%) | < 0.001 | 25 (10.2%) | 20 (8.2%) | 0.04 | 0.653 |
Laparoscopy | 474 (82.1%) | 278 (87.7%) | 208 (84.9%) | 215 (87.7%) | |||
Robot | 12 (2.1%) | 18 (5.7%) | 12 (4.9%) | 10 (4.1%) | |||
Splenic mobilization | 290 (50.3%) | 59 (18.6%) | < 0.001 | 61 (24.9%) | 57 (23.3%) | 0.038 | 0.673 |