Table 3.
DAG-guided multivariable Cox regression model analysis of causal effect of surgery on OS and CSS.
| Variables | OS | CSS | ||
|---|---|---|---|---|
| HR (95% CI) | p | HR (95% CI) | p | |
| Surgery | ||||
| Yes | Reference | Reference | ||
| No | 3.300 (1.568–6.946) | 0.004 | 3.398 (1.555–7.425) | 0.002 |
| Age (years) | 1.016 (1.002–1.029) | 0.020 | 1.009 (0.996–1.023) | 0.187 |
| Tumor size (mm) | 1.003 (1.001–1.005) | 0.010 | 1.003 (1.001–1.005) | 0.011 |
| Pathologic grade | ||||
| Grade I | Reference | Reference | ||
| Grade II | 0.591 (0.197–1.773) | 0.348 | 1.834 (0.220–15.331) | 0.575 |
| Grade III | 0.958 (0.356–2.580) | 0.933 | 3.628 (0.477–27.585) | 0.213 |
| Grade IV | 1.128 (0.413–3.082) | 0.814 | 4.120 (0.538–31.539) | 0.172 |
| T stage | ||||
| T1 | Reference | Reference | ||
| T2 | 1.403 (0.620–3.176) | 0.416 | 1.400 (0.549–3.573) | 0.481 |
| T3 | 1.510 (0.899–2.534) | 0.110 | 1.692 (0.954–3.001) | 0.072 |
| T4 | 1.1528 (0.550–2.416) | 0.706 | 1.239 (0.559–2.746) | 0.599 |
| N stage | ||||
| N0 | Reference | Reference | ||
| N1 | 1.486 (0.916–2.412) | 0.109 | 1.544 (0.928–2.570) | 0.095 |
| N2 | 1.156 (0.691–1.934) | 0.580 | 1.265 (0.742–2.159) | 0.388 |
| M stage | ||||
| M0 | Reference | Reference | ||
| M1 | 2.779 (1.814–4.257) | <0.001 | 2.867 (1.836–4.477) | <0.001 |
CDC, renal collecting duct carcinoma; DAG, directed acyclic graphs; CI, confidence interval; HR, hazard ratio; OS, overall survival; CSS, cancer-specific survival.