Table 2.
Univariate Cox proportional hazards analysis of the risk factors for lung cancer‐specific survival in surgically resected early SCLC (TN and period matching)
| Variable | Before matching | After matching | ||||
|---|---|---|---|---|---|---|
| HR | 95% CI | P | HR | 95% CI | P | |
| Pathology | < 0.001 | |||||
| NC‐SCLC | 1 | 1 | ||||
| C‐SCLC | 0.693 | 0.560–0.857 | 0.729 | 0.575–0.924 | 0.009 | |
| Age | 1.025 | 1.02–1.031 | < 0.001 | 1.026 | 1.015–1.037 | < 0.001 |
| Gender: male | 1.149 | 1.045–1.264 | 0.0042 | 1.111 | 0.910–1.357 | 0.301 |
| Race | ||||||
| African‐American | 1 | 1 | ||||
| Other | 1.135 | 0.857–1.504 | 0.376 | 1.192 | 0.603–2.354 | 0.614 |
| White | 0.991 | 0.825–1.190 | 0.921 | 1.244 | 0.816–1.898 | 0.310 |
| Year | 0.985 | 0.978–0.992 | < 0.001 | 0.992 | 0.975–1.009 | 0.354 |
| Marital status | ||||||
| Married | 1 | 1 | ||||
| Separated | 1.057 | 0.951–1.174 | 0.304 | 1.028 | 0.825–1.282 | 0.807 |
| Single | 0.819 | 0.684–0.980 | 0.029 | 0.809 | 0.557–1.173 | 0.263 |
| Unknown | 1.306 | 1.002–1.703 | 0.049 | 1.376 | 0.839–2.257 | 0.205 |
| Insurance | ||||||
| Insured | 1 | 1 | ||||
| Medicaid | 1.186 | 0.929–1.515 | 0.171 | 1.022 | 0.671–1.556 | 0.919 |
| Uninsured | 1.004 | 0.564–1.775 | 0.999 | 0.678 | 0.216–2129 | 0.505 |
| Unknown | 0.802 | 0.300–2.147 | 0.661 | 0.431 | 0.060–3.080 | 0.401 |
| Location | ||||||
| Lower | 1 | 1 | ||||
| Middle | 0.992 | 0.808–1.219 | 0.940 | 0.869 | 0.539–1.399 | 0.563 |
| Others | 1.171 | 0.975–1.407 | 0.092 | 1.269 | 0.843–1.911 | 0.254 |
| Upper | 0.905 | 0.813–1.007 | 0.068 | 0.943 | 0.751–1.185 | 0.614 |
| Laterality | ||||||
| Left | 1 | 1 | ||||
| Right | 1.024 | 0.931–1.128 | 0.623 | 0.969 | 0.792–1.185 | 0756 |
| Other | 2.622 | 1.088–6.321 | 0.032 | 0.796 | 0.111–5.689 | 0.819 |
| Operation | ||||||
| No surgery | 1 | 1 | ||||
| Lobectomy | 0.488 | 0.431–0.553 | < 0.001 | 0.510 | 0.398–0.652 | < 0.001 |
| Pneumonectomy | 0.918 | 0.590–1.428 | 0.704 | 0.513 | 0.191–1.377 | 0.185 |
| Sublobar | 0.673 | 0.566–0.799 | < 0.00 | 0.565 | 0.400–0.780 | 0.001 |
| CTx | 1.106 | 0.975–1.255 | 0.116 | 1.178 | 0.922–1.505 | 0191 |
| RT | 0.981 | 0.891–1.081 | 0.700 | 1.07 | 0.874–1.309 | 0.515 |
| Treatment | ||||||
| CTx | 1 | 1 | ||||
| CRT | 0.504 | 0.444–0.573 | < 0.001 | 0.479 | 0.360–0.637 | < 0.001 |
| RT | 0.732 | 0.583–0.919 | 0.008 | 0.527 | 0.325–0.854 | 0.009 |
| Surgery | 0.370 | 0.309–0.443 | < 0.001 | 0.332 | 0.232–0.476 | < 0.001 |
| Surgery + CTx | 0.293 | 0.244–0.352 | < 0.001 | 0.258 | 0.176–0.380 | < 0.001 |
| Surgery + CRT | 0.311 | 0.250–0.386 | < 0.001 | 0.257 | 0.161–0.411 | < 0.001 |
| Surgery + RT | 0.538 | 0.309–0.936 | 0.028 | 0.557 | 0.203–1529 | 0.256 |
| TNM stage | ||||||
| IA1 | 1 | 1 | ||||
| IA2 | 1.318 | 0.959–1.813 | 0.089 | 1.072 | 0.609–1.890 | 0.809 |
| IA3 | 1.514 | 1.101–2.083 | 0.011 | 1.641 | 0.943–2.855 | 0.080 |
| IB | 1.736 | 1.272–2.371 | 0.001 | 1.466 | 0.852–2.523 | 0.167 |
| IIA | 1.991 | 1.439–2.756 | < 0.001 | 2.069 | 1.132–3.783 | 0.018 |
| IIB | 1.893 | 1.390–2.577 | < 0.001 | 1.669 | 0.967–2.880 | 0.066 |
CI, confidence interval; C‐SCLC, combined small cell lung cancer; CTx, chemotherapy; CRT, chemoradiation; HR, hazard ratio; NC‐SCLC, non‐combined SCLC; RT, radiotherapy; TNM, tumor node metastasis.