Table 1.
Baseline characteristics of the cohort.
| Variables | Overall (n=1836) |
|---|---|
| Demographics | |
| Age, years, mean (SD) | 62.6 (11.8) |
| Gender, male, n (%) | 1098 (59.8) |
| BMI, kg/m2, mean (SD) | 23.7 (3.3) |
| Smoking, n (%) | 366 (19.9) |
| ECOG score, n (%) | |
| 0 | 803 (43.7) |
| 1 | 888 (48.3) |
| 2 | 127 (6.9) |
| 3 | 18 (0.9) |
| Disease history, n (%) | |
| Hypertension | 582 (31.6) |
| Diabetes | 264 (14.3) |
| Hepatic insufficiency | 16 (0.8) |
| Renal insufficiency | 15 (0.8) |
| Cardiac insufficiency | 41 (2.2) |
| CHD or cerebrovascular disease | 172 (9.3) |
| Varicose veins | 37 (2.0) |
| Lung disease | 77 (4.1) |
| History of tumor in other sites | 45 (2.4) |
| Previous surgical history (excluding ambulatory surgery) | 578 (31.4) |
| Procedure | |
| Operation approach, n (%) | |
| Laparoscopic | 1757 (95.6) |
| Open | 79 (4.3) |
| Operation time, min, mean (SD) | 212.3 (88.3) |
| Anesthesia time, min, mean (SD) | 233.92 (101.0) |
| Intraoperative bleeding, ml, median (P25–P75) | 50 (30–100) |
| Intraoperative blood transfusion, n (%) | 119 (6.4) |
| Histological type of tumor, n (%) | |
| Adenocarcinoma | 1712 (93.2) |
| Mucous adenocarcinoma | 88 (4.7) |
| Othersa | 36 (1.9) |
| Differentiation grade, n (%) | |
| Undifferentiated | 33 (1.7) |
| Poorly differentiated | 210 (11.4) |
| Moderately differentiated | 1502 (81.8) |
| High differentiation | 91 (4.9) |
| TNM staging, n (%) | |
| Phase 0 | 103 (5.6) |
| Phase I | 365 (19.9) |
| Phase II | 625 (34.0) |
| Phase III | 653 (35.6) |
| Phase IV | 90 (4.9) |
| Preoperative length of hospital stays, n (%) | |
| 0–4 days | 180 (9.8) |
| 5–10 days | 866 (47.2) |
| >10 days | 790 (43.0) |
a
Others including squamous cell carcinoma and undifferentiated carcinoma.
BMI, body mass index; CHD, coronary heart disease; ECOG, Eastern Cooperative Oncology Group.