Table 2. Prognostic factors in univariable and multivariable analyses for PFS (either patients or lesions).
| Prognostic factors affecting survival | Univariable analysis | Multivariable analysis | |||||
|---|---|---|---|---|---|---|---|
| HR | 95% CI | P | HR | 95% CI | P | ||
| Gender (male/female) | 1.007 | 0.576–1.761 | 0.98 | – | – | – | |
| Age (</≥65 years) | 1.029 | 0.672–1.574 | 0.90 | – | – | – | |
| Primary tumor location (yes/no) | 0.991 | 0.633–1.551 | 0.97 | 0.776 | 0.481–1.252 | 0.3 | |
| Number of metastasis in the lung (≤/>2) | 3.749 | 1.576–8.916 | 0.003 | 3.176 | 1.265–7.975 | 0.01 | |
| Distribution of metastasis (yes/no) | 0.585 | 0.370–0.923 | 0.02 | 0.605 | 0.370–0.989 | 0.045 | |
| ECOG-PS score (>/≤1) | 0.568 | 0.283–1.140 | 0.11 | 0.534 | 0.264–1.079 | 0.08 | |
| BED10 (</≥100 Gy) | 0.888 | 0.620–1.271 | 0.52 | – | – | – | |
| Toxicities (no/yes) | 1.457 | 0.844–2.516 | 0.18 | 1.696 | 0.972–2.959 | 0.06 | |
| Immunotherapy before SBRT (no/yes) | 0.541 | 0.322–0.909 | 0.02 | 0.523 | 0.302–0.906 | 0.02 | |
| Time from diagnosis to lung metastasis (</≥2 years) | 1.471 | 0.947–2.284 | 0.09 | – | – | – | |
| Diameter of tumor (</≥15 mm) | 0.826 | 0.531–1.286 | 0.40 | – | – | – | |
PFS, progression-free survival; ECOG-PS, Eastern Cooperative Oncology Group performance status; BED, biological equivalent dose; SBRT, stereotactic body radiotherapy; HR, hazard ratio; CI, confidence interval.