TABLE 3.
Multivariate Cox regression analyses for prognostic factors before propensity score matching (N = 1661)
| Characteristics | OS | DFS | ||
|---|---|---|---|---|
| HR (95% CI) | p | HR (95% CI) | p | |
| Sex | ||||
| Male | Ref | Ref | ||
| Female | 0.859 (0.664–1.111) | 0.247 | 0.924 (0.737–1.160) | 0.497 |
| Age (years) | ||||
| ≤60 | Ref | Ref | ||
| >60 | 1.369 (1.153–1.625) | <0.001 | 1.190 (1.019–1.389) | 0.028 |
| Tumor location | ||||
| RUL | Ref | Ref | ||
| RML | 1.231 (0.939–1.613) | 0.133 | 1.106 (0.865–1.415) | 0.422 |
| RLL | 1.222 (1.011–1.477) | 0.038 | 1.187 (1.002–1.405) | 0.048 |
| Anatomical type | ||||
| Central | Ref | Ref | ||
| Peripheral | 0.785 (0.611–1.010) | 0.059 | 0.852 (0.673–1.079) | 0.184 |
| Smoking history | ||||
| Never | Ref | Ref | ||
| Current/Former | 1.314 (1.040–1.659) | 0.022 | 1.336 (1.083–1.648) | 0.007 |
| Comorbidity | ||||
| No | Ref | Ref | ||
| Yes | 0.892 (0.754–1.054) | 0.180 | 1.012 (0.870–1.178) | 0.877 |
| Surgical resection | ||||
| Lobectomy | Ref | Ref | ||
| Bilobectomy | 0.983 (0.760–1.272) | 0.898 | 1.056 (0.836–1.335) | 0.646 |
| Pneumonectomy | 0.869 (0.559–1.351) | 0.532 | 0.888 (0.582–1.355) | 0.581 |
| Histology | ||||
| Adenocarcinoma | Ref | Ref | ||
| Squamous cell carcinoma | 0.792 (0.643–0.976) | 0.028 | 0.678 (0.558–0.824) | <0.001 |
| Others | 0.840 (0.601–1.174) | 0.308 | 0.843 (0.622–1.142) | 0.270 |
| Cell differentiation | ||||
| Well | Ref | Ref | ||
| Moderate | 1.328 (0.851–2.072) | 0.212 | 1.415 (0.954–2.097) | 0.084 |
| Poor | 1.817 (1.170–2.820) | 0.008 | 1.608 (1.086–2.381) | 0.018 |
| NA | 1.384 (0.780–2.457) | 0.267 | 1.349 (0.815–2.231) | 0.244 |
| Adjuvant therapy | ||||
| No | Ref | Ref | ||
| Yes | 0.814 (0.677–0.978) | 0.028 | 0.978 (0.830–1.153) | 0.793 |
| Pathological T category | ||||
| T1 | Ref | Ref | ||
| T2 | 1.419 (1.143–1.761) | 0.001 | 1.351 (1.117–1.634) | 0.002 |
| T3 | 2.072 (1.593–2.694) | <0.001 | 2.012 (1.586–2.552) | <0.001 |
| T4 | 2.078 (1.489–2.899) | <0.001 | 1.904 (1.404–2.583) | <0.001 |
| Pathological N category | ||||
| N0 | Ref | Ref | ||
| N1 | 1.477 (1.120–1.947) | 0.006 | 1.559 (1.224–1.987) | <0.001 |
| N2 | 2.755 (2.259–3.360) | <0.001 | 2.400 (2.005–2.872) | <0.001 |
| Postoperative complications | ||||
| No | Ref | Ref | ||
| Yes | 1.221 (0.908–1.643) | 0.187 | 1.208 (0.918–1.590) | 0.177 |
| No. of resected N1 LNs | 1.003 (0.985–1.022) | 0.732 | 1.005 (0.988–1.022) | 0.555 |
| No. of resected N2 LNs | 0.995 (0.985–1.006) | 0.361 | 0.992 (0.982–1.001) | 0.093 |
| 3A dissection | ||||
| 3A LND− | Ref | Ref | ||
| 3A LND+ | 1.214 (1.016–1.452) | 0.033 | 1.162 (0.988–1.367) | 0.070 |
Abbreviations: OS, overall survival; DFS, disease‐free survival; HR, hazard ratio; CI, confidence interval; Ref, reference; RUL, right upper lobe; RML, right middle lobe; RLL, right lower lobe; NA, not available; LND, lymph node dissection.