Table 1 Demographics comparison of the elderly and younger patients before PS matching
Variable | Aged < 70 years (n = 651) | Aged ≥ 70 years (n = 73) | P value | Standardized mean difference |
|---|---|---|---|---|
Age (years) | 56 (19–69) | 73 (70–83) | < 0.001 | |
Gender, male | 417 (64.1%) | 51 (69.9%) | 0.325 | 0.173 |
ASA | < 0.001 | 0.487 | ||
I–II | 596 (91.6%) | 48 (65.8%) | ||
III–IV | 55 (8.4%) | 25 (34.2%) | ||
Comorbidity | 274 (42.1%) | 50 (68.5%) | < 0.001 | 0.564 |
Cerebrovascular disease | 17 (2.6%) | 5 (6.8%) | 0.061 | 0.134 |
Arrhythmia | 9 (1.4%) | 1 (1.4%) | 1.000 | <0.001 |
Ischemic heart disease | 36(5.5%) | 9(12.3%) | 0.036 | 0.474 |
Diabetes mellitus | 94 (14.4%) | 15 (20.5%) | 0.166 | 0.265 |
Hypertension | 178 (27.3%) | 40 (54.8%) | < 0.001 | 0.648 |
Chronic obstructive pulmonary disease | 5 (0.8%) | 2 (2.7%) | 0.151 | 0.362 |
Chronic renal dysfunction | 4 (0.6%) | 1 (1.4%) | 0.413 | 0.242 |
Accompanying liver disease | 29 (4.5%) | 2 (2.7%) | 0.760 | 0.198 |
Primary tumor sideness | 0.198 | |||
Right side | 112 (17.2%) | 17 (23.3%) | ||
Left side | 539 (82.8%) | 56 (76.7%) | ||
Primary T | 0.659 | |||
pT1-T2 | 64 (9.8%) | 6 (8.2%) | ||
pT3-T4 | 587 (90.2%) | 67 (91.8%) | ||
Primary N | 0.869 | 0.087 | ||
pN0 | 199 (30.6%) | 23 (31.5%) | ||
pN1-2 | 452 (69.4%) | 50 (68.5%) | ||
Number of liver metastases(LM) | 0.032 | 0.674 | ||
≤ 3 | 447 (68.7%) | 59 (80.8%) | ||
> 3 | 204 (31.3%) | 14 (19.2%) | ||
Distribution of LM | 0.084 | |||
Unilobar | 341 (52.4%) | 46 (63.0%) | ||
Bilobar | 310 (47.6%) | 27 (37.0%) | ||
Maximum diameter of LM | 0.631 | |||
≤ 5 cm | 566 (86.9%) | 62 (84.9%) | ||
> 5 cm | 85 (13.1%) | 11 (15.1%) | ||
Temporal relationship | 0.796 | |||
Synchronous | 367 (56.4%) | 40 (54.8%) | ||
Metachronous | 284 (44.6%) | 33 (45.2%) | ||
Preoperative chemotherpy cycles | 0.025 | 0.743 | ||
≤ 6 cycles | 565 (86.8%) | 70 (95.9%) | ||
> 6 cycles | 86 (13.2%) | 3 (4.1%) | ||
Preoperative clinical risk score (CRS) | 0.590 | 0.234 | ||
0–2 | 344 (52.8%) | 41 (56.2%) | ||
3–5 | 307 (47.2%) | 32 (43.8%) | ||
RAS/BRAF mutation | 215(33.0%) | 27(37.0%) | 0.496 | 0.286 |
Preoperative CEA (ng/ml) | 8.19 (0.47–1351.00) | 8.53 (1.23–224.80) | 0.566 | 0.344 |
Preoperative CA199(U/ml) | 22.03 (0.00–29909.00) | 24.56 (0.00–1354.00) | 0.633 | |
Repeat resection after recurrence | 73 (11.2%) | 8 (11.0%) | 0.948 | 0.063 |
Postoperative chemotherapy | 442 (67.9%) | 40 (54.8%) | 0.024 | 0.766 |