Table 3. Univariate and multivariate analysis of factors associated with progression-free survival in ES-SCLC patients who received chemo-immunotherapy with TRT.
| Variable | Univariate analysis | Multivariate analysis | |||
|---|---|---|---|---|---|
| HR (95% CI) | P value | HR (95% CI) | P value | ||
| Age (≥65 vs. <65 years) | 0.61 (0.36–1.03) | 0.056 | – | – | |
| Gender (female vs. male) | 0.90 (0.46–1.77) | 0.767 | – | – | |
| Smoking status (yes vs. no) | 1.16 (0.70–1.94) | 0.563 | – | – | |
| ECOG-PS (>1 vs. ≤1) | 0.71 (0.17–2.91) | 0.633 | – | – | |
| Size of primary lesion (≥5 vs. <5 cm) | 1.51 (0.83–2.76) | 0.179 | – | – | |
| Mediastinal lymph node metastasis (yes vs. no) | 1.51 (0.80–2.84) | 0.202 | – | – | |
| Primary brain metastasis (yes vs. no) | 1.17 (0.62–2.20) | 0.630 | – | – | |
| Primary liver metastasis (yes vs. no) | 3.06 (1.58–5.93) | 0.001 | 2.82 (1.38–5.77) | 0.005 | |
| Number of initial distant metastases (≥3 vs. <3) | 1.54 (0.92–2.59) | 0.099 | – | – | |
| Superior vena cava syndrome (yes vs. no) | 1.44 (0.73–2.85) | 0.297 | – | – | |
| Pleural effusion (yes vs. no) | 1.96 (1.18–3.24) | 0.009 | 1.99 (1.18–3.33) | 0.010 | |
| Pericardial effusion (yes vs. no) | 1.35 (0.72–2.54) | 0.348 | – | – | |
| Immune checkpoint inhibitor | |||||
| Anti-PD-1 drug (yes vs. no) | 1.65 (1.00–2.71) | 0.050 | – | – | |
| Anti-PD-L1 drug (yes vs. no) | 0.55 (0.33–0.90) | 0.017 | – | 0.050 | |
| PCI (yes vs. no) | 0.50 (0.12–2.05) | 0.334 | – | – | |
| Extrathoracic radiotherapy (yes vs. no) | 1.12 (0.68–1.85) | 0.655 | – | – | |
| Consolidative TRT (yes vs. no) | 0.41 (0.23–0.73) | 0.002 | 0.44 (0.25–0.79) | 0.006 | |
| Timing of TRT (late vs. early) | 0.78 (0.48–1.28) | 0.325 | – | – | |
| Dose of TRT | |||||
| Conventional radiotherapy (yes vs. no) | 0.90 (0.45–1.81) | 0.767 | – | – | |
| Hyperfractionated radiotherapy (yes vs. no) | 0.63 (0.32–1.24) | 0.632 | – | – | |
| Hypofractionated radiotherapy (yes vs. no) | 1.52 (0.87–2.66) | 0.144 | – | – | |
| Response to systemic therapy before TRT (CR/PR vs. SD/PD) | 1.08 (0.63–1.85) | 0.773 | – | – | |
ES-SCLC, extensive-stage small cell lung cancer; HR, hazard ratio; CI, confidence interval; ECOG-PS, Eastern Cooperative Oncology Group performance status; PD-1, programmed cell death protein 1; PD-L1, programmed cell death ligand 1; PCI, prophylactic cranial irradiation; TRT, thoracic radiotherapy; CR, complete response; PR, partial response; SD, stable disease; PD, progressive disease.