Table 1. Baseline characteristics between female and male patients.
| Variables | Female (n=5,738) | Male (n=4,443) | P |
|---|---|---|---|
| Age, years, mean (SD) | 55.76 (10.95) | 58.71 (10.78) | <0.001 |
| BMI, kg/m2, mean (SD) | 22.67 (2.99) | 23.78 (2.90) | <0.001 |
| Smoking history, n (%) | <0.001 | ||
| Current | 36 (0.62) | 699 (15.7) | |
| Ever | 60 (1.05) | 2,256 (50.8) | |
| Never | 5,597 (97.5) | 1,433 (32.3) | |
| Missing | 45 (0.78) | 55 (1.23) | |
| HBP, n (%) | 969 (16.89) | 947 (21.31) | <0.001 |
| Coronary artery disease, n (%) | 80 (1.39) | 117 (2.63) | <0.001 |
| Chronic heart failure, n (%) | 4 (0.07) | 3 (0.07) | >0.99 |
| DM, n (%) | 303 (5.28) | 413 (9.30) | <0.001 |
| COPD, n (%) | 59 (1.03) | 271 (6.10) | <0.001 |
| Asthma, n (%) | 49 (0.85) | 17 (0.38) | 0.005 |
| Tuberculosis history, n (%) | 18 (0.31) | 14 (0.32) | >0.99 |
| FEV1%, mean (SD) | 108.71 (17.17) | 100.23 (19.35) | <0.001 |
| DLCO%, mean (SD) | 99.31 (15.50) | 101.16 (19.65) | <0.001 |
| Clinical AJCC stage, n (%) | <0.001 | ||
| I | 5,109 (89.04) | 3,178 (71.53) | |
| II | 291 (5.07) | 561 (12.63) | |
| III | 333 (5.80) | 691 (15.55) | |
| IV | 5 (0.09) | 13 (0.29) | |
| Neoadjuvant therapy, n (%) | 29 (0.51) | 98 (2.21) | <0.001 |
| Preoperative chemotherapy | 13 (0.23) | 89 (2.00) | <0.001 |
| Preoperative radiotherapy | 4 (0.07) | 6 (0.14) | 0.47 |
| Preoperative targeted therapy | 17 (0.30) | 10 (0.23) | 0.62 |
| VATS, n (%) | 5,580 (97.25) | 4,015 (90.37) | <0.001 |
| Conversion to open thoracotomy (%) | 69 (1.20) | 151 (3.40) | <0.001 |
| Resection extent, n (%) | <0.001 | ||
| Lobectomy | 3,491 (60.84) | 3,307 (74.43) | |
| Segmentectomy | 1,850 (32.24) | 824 (18.55) | |
| Wedge resection | 379 (6.61) | 261 (5.87) | |
| Pneumonectomy | 18 (0.31) | 51 (1.15) | |
| Tumor size, cm, mean (SD) | 1.79 (1.15) | 2.51 (1.60) | <0.001 |
| Histology, n (%) | <0.001 | ||
| Adenocarcinoma | 5,458 (95.12) | 3,322 (74.77) | |
| Squamous carcinoma | 81 (1.41) | 830 (18.68) | |
| Others* | 199 (3.47) | 291 (6.55) | |
| Pleural adhesion, n (%) | <0.001 | ||
| No | 2,429 (42.70) | 1,823 (41.39) | |
| Moderate | 2,870 (50.45) | 2,126 (48.27) | |
| Complete | 390 (6.86) | 455 (10.33) | |
| Missing | 49 (0.85) | 39 (0.87) | |
| Uncompleted intralobular fissure, n (%) | 2,724 (47.47) | 2,105 (47.38) | 0.001 |
| Surgery duration, min, mean (SD) | 108.43 (43.23) | 127.78 (55.80) | <0.001 |
P values are calculated using the Chi-squared test for categorical variables and the Student’s t-test for continuous variables. *, others included adenosquamous carcinoma, large cell carcinoma, undifferentiated cancers, neuroendocrine tumor, and salivary gland tumor. SD, standard difference; BMI, body mass index; HBP, high blood pressure; DM, diabetes mellitus; COPD, chronic obstructive pulmonary disease; FEV1%, predicted percentage of forced expiratory volume in 1 second; DLCO%, predicted percentage of diffusing capacity for carbon monoxide; AJCC, American Joint Committee on Cancer; VATS, video-assisted thoracoscopic surgery.