TABLE 1.
General clinicopathological characteristics of patients with and without station 3A LND before and after propensity score matching
| Characteristics | Entire cohort (N = 1661) | p | Propensity score matching (N = 988) | p | ||
|---|---|---|---|---|---|---|
| Without 3A LND (N = 1158) | With 3A LND (N = 503) | Without 3A LND (N = 494) | With 3A LND (N = 494) | |||
| Sex | 0.254 | 0.790 | ||||
| Male | 786 (67.9) | 327 (65.0) | 318 (64.4) | 322 (65.2) | ||
| Female | 372 (32.1) | 176 (35.0) | 176 (35.6) | 172 (34.8) | ||
| Age (years) | 0.003 | 0.564 | ||||
| ≤60 | 588 (50.8) | 216 (42.9) | 233 (45.1) | 214 (43.3) | ||
| >60 | 570 (49.2) | 287 (57.1) | 271 (54.9) | 280 (56.7) | ||
| Mean ± SD | 58.9 ± 9.8 | 60.1 ± 8.9 | 0.025 a | 59.5 ± 9.8 | 60.0 ± 8.9 | 0.844 a |
| Median (min., max.) | 59.0 (25, 81) | 61.0 (24, 81) | 61.0 (25, 79) | 60.5 (24, 81) | ||
| Pathological stage | 0.003 | 0.719 | ||||
| I | 542 (46.8) | 208 (41.4) | 198 (40.1) | 206 (41.7) | ||
| II | 259 (22.4) | 97 (19.3) | 107 (21.7) | 97 (19.6) | ||
| III | 357 (30.8) | 198 (39.4) | 189 (38.3) | 191 (38.7) | ||
| Pathological T category | 0.238 | 0.726 | ||||
| T1 | 370 (32.0) | 152 (30.2) | 155 (31.4) | 151 (30.6) | ||
| T2 | 541 (46.7) | 228 (45.3) | 224 (45.3) | 225 (45.5) | ||
| T3 | 175 (15.1) | 78 (15.5) | 80 (16.2) | 74 (15.0) | ||
| T4 | 72 (6.2) | 45 (8.9) | 35 (7.1) | 44 (8.9) | ||
| Pathological N category | 0.004 | 0.671 | ||||
| N0 | 743 (64.2) | 287 (57.1) | 277 (56.1) | 285 (57.7) | ||
| N1 | 139 (12.0) | 57 (11.3) | 64 (13.0) | 55 (11.1) | ||
| N2 | 276 (23.8) | 159 (31.6) | 153 (31.0) | 154 (31.2) | ||
| Tumor location | 0.021 | 0.455 | ||||
| RUL | 619 (53.5) | 259 (51.5) | 270 (54.7) | 256 (51.8) | ||
| RML | 126 (10.9) | 79 (15.7) | 64 (13.0) | 77 (15.6) | ||
| RLL | 413 (35.7) | 165 (32.8) | 160 (32.4) | 161 (32.6) | ||
| Anatomical type | 0.024 | 0.927 | ||||
| Central | 127 (11.0) | 75 (14.9) | 69 (14.0) | 70 (14.2) | ||
| Peripheral | 1031 (89.0) | 428 (85.1) | 425 (86.0) | 424 (85.8) | ||
| Smoking history | 0.528 | 0.848 | ||||
| Never | 549 (47.4) | 230 (45.7) | 223 (45.1) | 226 (45.7) | ||
| Current/former | 609 (52.6) | 273 (54.3) | 271 (54.9) | 268 (54.3) | ||
| Comorbidity | 0.981 | 0.949 | ||||
| No | 574 (49.6) | 249 (49.5) | 243 (49.2) | 244 (49.4) | ||
| Yes | 584 (50.4) | 254 (50.5) | 251 (50.8) | 250 (50.6) | ||
| Surgical approach | 0.590 | 0.458 | ||||
| Thoracotomy | 851 (73.5) | 376 (74.8) | 379 (76.7) | 369 (74.7) | ||
| Thoracoscopic | 307 (26.5) | 127 (25.2) | 115 (23.3) | 125 (25.3) | ||
| Surgical resection | 0.055 | 0.921 | ||||
| Lobectomy | 991 (85.6) | 408 (81.1) | 398 (80.6) | 403 (81.6) | ||
| Bilobectomy | 136 (11.7) | 74 (14.7) | 77 (15.6) | 73 (14.8) | ||
| Pneumonectomy | 31 (2.7) | 21 (4.2) | 19 (3.8) | 18 (3.6) | ||
| Histology | 0.023 | 0.561 | ||||
| Adenocarcinoma | 770 (66.5) | 321 (63.8) | 303 (61.3) | 317 (64.2) | ||
| Squamous cell carcinoma | 317 (27.4) | 132 (26.2) | 143 (28.9) | 128 (25.9) | ||
| Others | 71 (6.1) | 50 (9.9) | 48 (9.7) | 49 (9.9) | ||
| Cell differentiation | 0.495 | 0.949 | ||||
| Well | 76 (6.6) | 34 (6.8) | 32 (6.5) | 34 (6.9) | ||
| Moderate | 477 (41.2) | 187 (37.2) | 191 (38.7) | 184 (37.2) | ||
| Poor | 539 (46.5) | 251 (49.9) | 238 (48.2) | 245 (49.6) | ||
| NA | 66 (5.7) | 31 (6.2) | 33 (6.7) | 31 (6.3) | ||
| Tumor size (cm) | 0.164 a | 0.869 a | ||||
| Mean ± SD | 3.6 ± 2.0 | 3.8 ± 2.1 | 3.7 ± 2.0 | 3.8 ± 2.1 | ||
| Median (min., max.) | 3.0 (0.5, 14.0) | 3.0 (0.3, 13.0) | 3.0 (0.5, 14.0) | 3.0 (0.3, 13.0) | ||
| Adjuvant therapy | 0.220 | 0.949 | ||||
| No | 657 (56.7) | 269 (53.5) | 263 (53.2) | 262 (53.0) | ||
| Yes | 501 (43.3) | 234 (46.5) | 231 (46.8) | 232 (47.0) | ||
| Complication | 0.920 | 0.533 | ||||
| No | 1079 (93.2) | 468 (93.0) | 457 (92.5) | 462 (93.5) | ||
| Yes | 79 (6.8) | 35 (7.0) | 37 (7.5) | 32 (6.5) | ||
| No. of resected TLNs | <0.001 a | 0.688 a | ||||
| Mean ± SD | 22.3 ± 10.0 | 25.0 ± 11.2 | 24.8 ± 10.8 | 24.7 ± 10.9 | ||
| Median (min, max) | 21.0 (4, 84) | 23.0 (5, 78) | 23.0 (4, 77) | 23.0 (5, 78) | ||
| No. of resected MLNs | <0.001 a | 0.478 a | ||||
| Mean ± SD | 15.0 ± 7.7 | 17.7 ± 8.5 | 17.3 ± 8.7 | 17.4 ± 8.0 | ||
| Median (min, max) | 14.0 (3, 60) | 17.0 (3, 67) | 16.0 (3, 55) | 16.0 (3, 52) | ||
| Drainage of POD1 (ml) | 0.041 | 0.145 | ||||
| Mean ± SD | 481.3 ± 238.4 | 516.1 ± 281.5 | 484.3 ± 231.9 | 515.9 ± 282.7 | ||
| Median (min, max) | 460.0 (0, 2410) | 500.0 (0, 2710) | 460.0 (0, 1450) | 500.0 (0, 2710) | ||
| Hospital stays (days) | 0.851 | 0.239 | ||||
| Mean ± SD | 10.2 ± 6.2 | 12.5 ± 29.3 | 10.7 ± 6.8 | 10.0 ± 5.3 | ||
| Median (min, max) | 9.0 (2, 89) | 9.0 (1, 379) | 9.0 (2, 79) | 9.0 (3, 65) | ||
Abbreviations: LND, lymph node dissection; SD, standard deviations; RUL, right upper lobe; RML, right middle lobe; RLL, right lower lobe; NA, not available, TLNs, total lymph nodes; MLNs, mediastinal lymph nodes; POD1, postoperative day 1.
a
Mann–Whitney U test.