|  | All case | Group NAL | Group AL |  |
---|---|---|---|---|---|
 |  | N = 295 | N = 261 | N = 34 | p value |
Thoracic procedure | MIE | 220 (74.6%) | 192 (75.6%) | 28 (82.4%) | 0.268 |
 | Open | 75 (25.4%) | 69 (26.4%) | 6 (17.6%) |  |
Abdominal procedure | HALS | 277 (93.9%) | 246 (94.3%) | 31 (91.2%) | 0.447* |
 | Open | 18 (6.1%) | 15 (5.7%) | 3 (8.8%) |  |
Lymoph node dissection | Three-field | 278 (94.3%) | 248 (95.0%) | 30 (88.2%) | 0.118* |
 | Two-field | 17 (5.8%) | 13 (5.0%) | 4 (11.8%) |  |
Operation time | (minutes, IQR) | 561 (509–613) | 556 (506–611) | 598 (550–636) | 0.02 |
 |  > 565 | 137 (46.4%) | 114 (43.7%) | 23 (67.7%) | 0.008 |
 |  ≤ 565 | 158 (53.6%) | 147 (56.3%) | 11 (32.4%) |  |
Blood loss | (mL, IQR) | 300 (190–550) | 275 (180–540) | 335 (223–743) | 0.078 |
 |  ≥ 480 | 85 (28.8%) | 70 (26.8%) | 15 (44.1%) | 0.036 |
 |  < 480 | 210 (71.2%) | 191 (73.2%) | 19 (55.9%) |  |
Anastomosis method | Hand-sewn | 160 (54.2%) | 144 (55.2%) | 16 (47.1%) | 0.372 |
 | Mechanical | 135 (45.8%) | 117 (44.8%) | 18 (52.9%) |  |
Reconstruction route | Retrosternal | 178 (60.3%) | 157 (60.2%) | 21 (61.8%) | 0.856 |
 | Posterior mediastinal | 117 (39.7%) | 104 (39.8%) | 13 (38.4%) |  |
Residual tumor | R0 | 285 (96.6%) | 251 (96.2%) | 34 (100%) | 0.612* |
 | R1 | 10 (3.4%) | 10 (3.8%) | 0 (0.0%) |  |
Timing of surgery | 2007–2014 | 125 (42.4%) | 110 (42.2%) | 15 (44.1%) | 0.827 |
 | 2015–2020 | 170 (57.6%) | 151 (57.9%) | 19 (55.9%) |  |