Variables | Entire cohort | Propensity score matching | ||||
---|---|---|---|---|---|---|
S4RD− no. (%) | S4RD+ no. (%) | P | S4RD− no. (%) | S4RD+ no. (%) | P | |
No. | 207 | 1863 | Â | 205 | 799 | Â |
Age (year) | Â | Â | 0.860 | Â | Â | 0.945 |
 ≥ 65 | 63 (30.4) | 551 (29.6) |  | 63 (30.7) | 250 (31.3) |  |
 < 65 | 144 (69.6) | 1312 (70.4) |  | 142 (69.3) | 549 (68.7) |  |
Gender | Â | Â | 0.368 | Â | Â | 0.808 |
 Male | 109 (52.7) | 1047 (56.2) |  | 107 (52.2) | 407 (50.9) |  |
 Female | 98 (47.3) | 816 (43.8) |  | 98 (47.8) | 392 (49.1) |  |
Smoking history |  |  | < 0.001 |  |  | 0.926 |
 Yes | 92 (44.4) | 1080 (58.0) |  | 91 (44.4) | 360 (45.1) |  |
 No | 115 (45.6) | 783 (42) |  | 114 (55.6) | 439 (54.9) |  |
Surgical approaches | Â | Â | 0.791 | Â | Â | 0.585 |
 Thoracotomy | 114 (55.1) | 1003 (53.8) |  | 112 (54.6) | 417 (52.2) |  |
 Thoracoscopic surgery | 93 (44.9) | 860 (46.2) |  | 93 (45.4) | 382 (47.8) |  |
Tumor location | Â | Â | 0.025 | Â | Â | 0.710 |
 Upper lobe | 91 (44.0) | 645 (34.6) |  | 97 (47.3) | 373 (46.7) |  |
 Middle lobe | 19 (9.2) | 224 (12.0) |  | 19 (9.3) | 90 (11.3) |  |
 Lower lobe | 97 (46.9) | 994 (53.4) |  | 89 (43.4) | 336 (42.1) |  |
Histological type | Â | Â | 0.065 | Â | Â | 0.601 |
 Adenocarcinoma | 157 (75.8) | 1265 (67.9) |  | 155 (75.6) | 630 (78.8) |  |
 Squamous cell carcinoma | 33 (15.9) | 397 (21.3) |  | 33 (16.1) | 113 (14.1) |  |
 Others | 17 (8.2) | 201 (10.8) |  | 17 (8.3) | 56 (7.0) |  |
Adjuvant chemotherapy | Â | Â | 0.218 | Â | Â | 0.415 |
 No | 140 (67.6) | 1174 (63.0) |  | 140 (68.3) | 519 (65.0) |  |
 Yes | 67 (32.4) | 689 (37.0) |  | 65 (31.7) | 280 (35.0) |  |
pT | Â | Â | 0.436 | Â | Â | 0.943 |
 T1a | 23 (11.1) | 169 (9.1) |  | 23 (11.2) | 88 (11.0) |  |
 T1b | 59 (28.5) | 557 (29.9) |  | 59 (28.8) | 240 (30.0) |  |
 T1c | 56 (27.1) | 524 (28.1) |  | 56 (27.3) | 224 (28.0) |  |
 T2a | 27 (13.0) | 252 (13.5) |  | 27 (13.2) | 110 (13.8) |  |
 T2b | 17 (8.2) | 157 (8.4) |  | 17 (8.3) | 49 (6.1) |  |
 T3 | 13 (6.3) | 147 (7.9) |  | 13 (6.3) | 56 (7.0) |  |
 T4 | 12 (5.8) | 57 (3.1) |  | 10 (4.9) | 32 (4.0) |  |
pN | Â | Â | 0.058 | Â | Â | 0.565 |
 N0 | 162 (78.3) | 1355 (72.7) |  | 162 (79.0) | 628 (78.6) |  |
 N1 | 15 (7.2) | 109 (5.9) |  | 14 (6.8) | 42 (5.3) |  |
 N2 | 30 (14.5) | 399 (21.4) |  | 29 (14.1) | 129 (16.1) |  |