Table 2.
Univariate analysis examining for variables associated with increased likelihood of local failure using a proportional hazards model.
| Variable | 1-year Local Control | p value |
|---|---|---|
| Age | 0.491 | |
| ≤60 | 92% | |
| >60 | 81% | |
| Gender | 0.718 | |
| Male | 89% | |
| Female | 84% | |
| Surgery vs no surgery | 0.234 | |
| Vertebrectomy | 76% | |
| Laminectomy | 90% | |
| Definitive | 96% | |
| Radiotherapy dose (BED) | 0.652 | |
| ≥51.3Gy | 80% | |
| <51.3Gy | 90% | |
| PTV minimum dose (BED) | 0.486 | |
| ≥29.2Gy | 83% | |
| <29.2Gy | 81% | |
| PTV mean dose (BED) | 0.550 | |
| ≥55.23Gy | 90% | |
| <55.23Gy | 74% | |
| D90% (BED) | 0.604 | |
| ≥52Gy | 85% | |
| <52Gy | 90% | |
| D95% (BED) | 0.262 | |
| ≥51.3Gy | 83% | |
| <51.3Gy | 92% | |
| PTV coverage | 0.445 | |
| ≥95% | 86% | |
| <95% | 100% | |
| Number of fractions | 0.293 | |
| 1 | 88% | |
| 3 | 83% | |
| 5 | 100% | |
| Treated volume | 0.042 | |
| <132cc | 96% | |
| ≥132cc | 79% | |
| Systemic disease status | 0.028 | |
| Stable | 94% | |
| Uncontrolled | 62% | |
| SINS | 0.44 | |
| ≤7 | 96% | |
| >7 | 77% | |
| Bilsky | 0.412 | |
| Grade 1a-c | 96% | |
| Grade 2-3 | 76% |
BED, biologically effective dose; PTV, planning target volume; SINS, spinal instability neoplastic score. The bold values: statistically significant values.