Table IV.
Univariate analysis of factors that affected OS and PFS.
| OS | PFS | ||||||
|---|---|---|---|---|---|---|---|
| Factors | N | Median (months) | 95% CI (months) | P-value | Median (months) | 95% CI (months) | P-value |
| GTV | |||||||
| >20 cm3 | 18 | 14.5 | 9.6-30.5 | 0.12 | 7.5 | 2.8-16.8 | 0.052 |
| ≤20 cm3 | 22 | 40.1 | 12.9-NA | 34.2 | 6.4-NA | ||
| Interval between the primary therapy and OM (years) | |||||||
| ≤1 | 7 | 19.5 | 6.8-NA | 0.32 | 10.0 | 2.8-NA | 0.29 |
| >1 | 33 | 23.0 | 13.3-NA | 11.3 | 5.3-NA | ||
| ≤2 | 20 | 18.2 | 8.4-30.5 | 0.041 | 7.7 | 1.9-16.8 | 0.028 |
| >2 | 20 | 29.4 | 13.3-NA | 34.2 | 6.4-NA | ||
| Primary tumor | |||||||
| Esophagus | 18 | 13.8 | 8.4-23.0 | 0.026 | 7.7 | 2.8-15.6 | 0.10 |
| Lung | 8 | 30.5 | 9.6-NA | 16.8 | 2.2-NA | ||
| Others | 14 | NA | 10.1-NA | NA | 2.4-NA | ||
| SBRT target | |||||||
| Mediastinum | 25 | 23.0 | 12.9-NA | 0.65 | 15.6 | 7.7-34.2 | 0.55 |
| Others | 15 | 14.5 | 8.5-NA | 6.4 | 1.7-NA | ||
| Primary treatment | |||||||
| Surgical resection | 30 | 29.4 | 13.3-NA | 0.088 | 10.5 | 5.3-NA | 0.57 |
| Others | 10 | 22.5 | 6.8-NA | 11.3 | 0.7-NA | ||
P-values calculated via log-rank test. OS, overall survival; PFS, progression-free survival; GTV, gross tumor volume; OM, oligometastasis; SBRT, stereotactic body radiation therapy; NA, not applicable (still alive); CI, confidence interval.