Table 2. Results of univariate and multivariate analysis for recurrence-free survival.
| Covariate | Univariate | Multivariate | |||||
|---|---|---|---|---|---|---|---|
| HR | 95% CI | P value | HR | 95% CI | P value | ||
| Age (≥65 vs. <65 years) | 0.97 | 0.59–1.58 | 0.89 | NA | NA | NA | |
| Male vs. female | 1.53 | 0.94–2.51 | 0.09 | 1.81 | 0.81–4.02 | 0.15 | |
| Smoking status | |||||||
| Light vs. never | 1.19 | 0.57–2.45 | 0.65 | 0.39 | 0.13–1.18 | 0.09 | |
| Heavy vs. never | 2.61 | 1.36–5.00 | 0.004 | 1.33 | 0.52–3.42 | 0.56 | |
| ECOG PS | |||||||
| 1 vs. 0 | 1.60 | 0.95–2.69 | 0.08 | 1.33 | 0.74–2.42 | 0.35 | |
| 2 vs. 0 | 4.73 | 1.10–20.29 | 0.04 | 0.98 | 0.19–5.12 | 0.98 | |
| Tumor size (≥4 vs. <4 cm) | 3.41 | 2.02–5.75 | <0.001 | 1.94 | 1.03–3.67 | 0.04 | |
| Adenocarcinoma subtype (solid vs. non-solid) | 1.91 | 0.91–4.03 | 0.09 | 1.36 | 0.38–4.82 | 0.64 | |
| Histologic grading | |||||||
| Grade 1 | 1 | 1 | |||||
| Grade 2 | 3.12 | 1.75–5.57 | <0.001 | 1.35 | 0.65–2.83 | 0.42 | |
| Grade 3 | 3.25 | 1.59–6.63 | 0.001 | 0.81 | 0.24–2.73 | 0.73 | |
| Lymphovascular invasion (yes vs. no) | 2.86 | 1.73–4.75 | <0.001 | 1.16 | 0.60-2.21 | 0.67 | |
| Visceral pleural invasion (yes vs. no) | 3.48 | 2.11–5.72 | <0.001 | 2.53 | 1.34–4.79 | 0.004 | |
| Tumor necrosis (yes vs. no) | 4.58 | 2.75–7.62 | <0.001 | 2.45 | 1.13–5.31 | 0.023 | |
| EGFR mutation (yes vs. no) | 0.95 | 0.55–1.65 | 0.85 | 1.20 | 0.66–2.18 | 0.56 | |
| Bronchial resection margin (<2 vs. ≥2 cm) | 2.34 | 1.41–3.90 | 0.001 | 1.96 | 1.10–3.51 | 0.023 | |
HR, hazard ratio; CI, confidence interval; NA, not applicable; ECOG, Eastern Cooperative Oncology Group; PS, performance status.