Table 2. Univariate Cox regression analysis between variables and overall survival and disease-free survival.
| Overall survival (OS) | Disease-free survival (DFS) | |||
|---|---|---|---|---|
| Variables | P-value | HR [95% CI] | P-value | HR [95% CI] |
| Age | < 0.001 | 1.041 [1.020–1.063] | 0.004 | 1.027 [1.009–1.046] |
| Sex (male vs. female) | 0.786 | 0.884 [0.363–2.155] | 0.895 | 0.947 [0.420–2.134] |
| Radiologic variables | ||||
| Location (peripheral vs. central) | 0.503 | 1.115 [0.812–1.530] | 0.724 | 1.052 [0.792–1.398] |
| Obstructive pneumonitis/atelectasis | 0.012 | 0.664 [0.484–0.913] | 0.041 | 0.746 [0.562–0.988] |
| Enhancement ratio | 0.706 | 0.921 [0.599–1.414] | 0.845 | 0.963 [0.657–1.410] |
| Heterogeneity (HU) | < 0.001 | 1.016 [1.007–1.025] | 0.166 | 1.009 [0.996–1.021] |
| Necrosis | 0.106 | 1.328 [0.942–1.873] | 0.058 | 1.342 [0.990–1.820] |
| Cavitation | 0.039 | 1.775 [1.029–3.063] | 0.237 | 1.383 [0.808–2.367] |
| CT-determined lung disease | < 0.001 | < 0.001 | ||
| Emphysema | 0.048 | 1.452 [1.004–2.099] | 0.083 | 1.338 [0.962–1.861] |
| Interstitial lung abnormalities | < 0.001 | 6.208 [3.680–10.47] | < 0.001 | 4.374 [2.624–7.290] |
| Pleural effusion | 0.619 | 1.254 [0.515–3.056] | 0.833 | 0.909 [0.374–2.209] |
| Clinical variables | ||||
| Bronchoscopic detectability | 0.110 | 0.773 [0.563–1.060] | 0.468 | 0.899 [0.676–1.197] |
| FEV1 (% PRED) | 0.508 | 1.003 [0.994–1.012] | 0.510 | 0.997 [0.989–1.005] |
| FEV1/FVC (%) | 0.129 | 1.011 [0.997–1.025] | 0.665 | 1.003 [0.990–1.015] |
| Serum CEA | 0.585 | 0.998 [0.989–1.006] | 0.403 | 0.996 [0.987–1.005] |
| Mode of surgery (subpneumonectomy vs. pneumonectomy) | 0.235 | 0.778 [0.514–1.177] | 0.207 | 0.786 [0.541–1.142] |
| Any adjuvant therapy (+) | 0.696 | 1.069 [0.765–1.494] | 0.053 | 1.354 [0.996–1.842] |
| Histopathologic variables | ||||
| Pathologic T stage | 0.086 | 0.158 | ||
| T2 vs. T1 | 0.364 | 1.235 [0.783–1.950] | 0.498 | 1.147 [0.772–1.704] |
| T3 vs. T1 | 0.024 | 1.816 [1.082–3.049] | 0.060 | 1.555 [0.982–2.464] |
| T4 vs. T1 | 0.216 | 1.841 [0.699–4.847] | 0.143 | 1.924 [0.802–4.614] |
| Pathologic N stage | 0.013 | 0.075 | ||
| N1 vs. N0 | 0.192 | 1.277 [0.884–1.845] | 0.305 | 1.190 [0.854–1.657] |
| N2 vs. N0 | 0.004 | 1.920 [1.233–2.989] | 0.027 | 1.592 [1.055–2.402] |
| Differentiation | 0.480 | 0.420 | ||
| MD vs. WD | 0.875 | 1.043 [0.616–1.768] | 0.952 | 0.986 [0.615–1.580] |
| PD/DD vs. WD | 0.388 | 1.290 [0.723–2.301] | 0.437 | 1.228 [0.732–2.062] |
| Lymph node ratio | 0.525 | 1.365 [0.523–3.564] | 0.844 | 1.098 [0.434–2.777] |
CEA, carcinoembryonic antigen; DD, dedifferentiated; FEV1, forced expiratory volume in a second; FVC, forced vital capacity; MD, moderately differentiated; PD, poorly differentiated; WD, well-differentiated. Data with a p-value less than or equal to 0.05 are indicated by bold text.