Table 2 Intraoperative and postoperative outcomes of the cohort before and after PSM
Variables | Before PSM (n = 170) | After PSM (n = 105) | ||||||
|---|---|---|---|---|---|---|---|---|
All (n = 170) | LLR (n = 127) | OLR (n = 43) | p-value | All (n = 105) | LLR (n = 70) | OLR (n = 35) | p-value | |
Lymphadenectomy ≥ 6, n (%) | 67 (39.4) | 46 (36.2) | 21 (48.8) | 0.143 | 37 (35.2) | 23 (32.9) | 14 (40.0) | 0.470 |
Duration of surgery (IQR), min | 240 (180–310) | 240 (179–305) | 270 (190–345) | 0.183 | 238 (180–328) | 238 (174–318) | 238 (181–344) | 0.687 |
Blood transfusion, n (%) | 64 (37.6) | 33 (26.0) | 31 (72.1) |  < 0.001 | 45 (42.9) | 21 (30.0) | 24 (68.6) | < 0.001 |
Estimated blood loss (IQR), ml | 300 (100–725) | 200 (100–500) | 800 (300–1500) |  < 0.001 | 300 (150–800) | 200 (100–525) | 500 (200–1500) | 0.003 |
Conversion to open, n (%) | - | 30 (23.6) | - | Â | Â | Â | Â | Â |
Major sizes, median (IQR), cm | 4.8 (3.5–6.5) | 4.5 (3.5–6.0) | 5.4 (3.1–7.5) | 0.283 | 5.0 (3.7–6.5) | 4.6 (3.9–6.1) | 5.4 (3.1–7.5) | 0.441 |
Multiple tumors, n (%) | 31 (18.2) | 21 (16.5) | 10 (23.3) | 0.323 | 13 (12.4) | 7 (10.0) | 6 (17.1) | 0.295 |
Complications, n (%) | 57 (33.5) | 37 (29.1) | 20 (46.5) | 0.036 | 29 (29.5) | 16 (22.9) | 13 (37.1) | 0.122 |
Clavien-Dindo classification | ||||||||
 Minor (I/II) | 28 (16.5) | 22 (17.3) | 6 (14.0) | 0.606 | 14 (13.3) | 10 (14.2) | 4 (11.4) | 0.701 |
 Major (III/IV) | 29 (17.0) | 15 (11.8) | 14 (32.6) | 0.002 | 15 (14.3) | 6 (8.5) | 9 (25.7) | 0.017 |
Serious complications, n (%) | ||||||||
 Massive ascites | 18 (10.5) | 11 (8.7) | 7 (16.3) |  | 7 (6.7) | 3 (4.3) | 4 (11.4) |  |
 Massive pleural effusion | 17 (10.0) | 9 (7.1) | 7 (16.3) |  | 8 (7.6) | 4 (5.7) | 4 (11.4) |  |
 Abdominal hemorrhage | 4 (2.3) | 2 (1.6) | 2 (4.7) |  | 1 (0.1) | 0 (0) | 1 (2.9) |  |
 Bile leakage | 3 (1.7) | 1 (0.8) | 2 (4.7) |  | 1 (0.1) | 0 (0) | 1 (2.9) |  |
 Multiple organ failure | 5 (2.9) | 0 (0) | 5 (11.6) |  | 4 (3.8) | 0 (0) | 4 (11.4) |  |
Postoperative hospital stay | 10 (7–16) | 10 (6–15) | 13 (9–22) | 0.012 | 11 (8–17) | 10 (7–16) | 12 (8–21) | 0.132 |
Tumor differentiation, n (%) | Â | Â | Â | 0.493 | Â | Â | Â | 0.724 |
 High | 28 (16.4) | 21 (16.5) | 7 (16.2) |  | 15 (14.3) | 10 (14.3) | 5 (14.3) |  |
 Middle | 47 (27.6) | 32 (25.1) | 15 (34.8) |  | 27 (25.7) | 16 (22.9) | 11 (31.4) |  |
 Low | 68 (40.0) | 53 (41.7) | 15 (34.8) |  | 43 (41.0) | 29 (41.4) | 14 (40.0) |  |
NA | 27 (15.8) | 0 (0) | 6 (13.9) | Â | 20 (19.0) | 15 (21.4) | 5 (14.3) | Â |
Lymph node metastasis | 44 (25.8) | 31 (24.4) | 13 (30.2) | 0.451 | 28 (26.7) | 17 (24.3) | 11 (31.4) | 0.435 |
Nerve invasion | 36 (21.1) | 31 (24.4) | 6 (11.6) | 0.151 | 18 (17.1) | 16 (22.9) | 2 (5.7) | 0.028 |
R0 resection | 157 (92.3) | 118 (92.9) | 39 (90.7) | 0.637 | 97 (92.4) | 65 (92.9) | 32 (91.4) | 0.795 |