Table 4.
Cox Proportional Hazards Modeling.
| Cox Proportional Hazards | Radiographic Failure | Unadjusted Pain Relief | Unadjusted Pain Progression | Adjusted Pain Progression | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Covariates | Multivariate | Multivariate | Multivariate | Multivariate | ||||||||
| P | HR | 95% CI | P | HR | 95% CI | P | HR | 95% CI | P | HR | 95% CI | |
| Age, years | <.01 | 0.81 | 0.70-0.90 | .16 | 0.93 | 0.81-1.03 | ||||||
| Male gender | .06 | 4.63 | 0.94-23.66 | |||||||||
| KPS > 70 | <.01 | 0.07 | 0.01-0.28 | .01 | 0.12 | 0.02-0.62 | <.01 | 0.04 | 0.01-0.22 | |||
| BPI pain at consult | <.01 | 1.92 | 1.18-3.36 | |||||||||
| Indication for SRSa | <.01 | |||||||||||
| Neurologic deficit | ||||||||||||
| Pain and neurologic deficit | <.01 | 2.48 | 1.30-4.76 | |||||||||
| Asymptomatic | ||||||||||||
| No. previous chemo. regimens | <.01 | 12.34 | 2.18->100 | |||||||||
| Bone metastases | <.01 | 2.83 | 1.49-5.98 | |||||||||
| Posterior elements disease | .04 | 2.16 | 1.04-4.65 | |||||||||
| Any prior radiotherapy | .02 | 4.65 | 1.30-20.24 | |||||||||
| PTV coverage, % | .07 | 0.67 | 0.43-1.03 | .04 | 0.44 | 0.19-0.96 | ||||||
| Minimum target dose, Gy | .02 | 0.48 | 0.22-0.89 | |||||||||
| Target volume, mL | .01 | 0.99 | 0.98-1.00 | 0.19 | 1.00 | 0.99-1.00 | ||||||
| No. treated levels | <.01 | .03 | ||||||||||
| 2 versus 1 | <.01 | 58.81 | 5.36->100 | .12 | 0.47 | 0.01-5.72 | ||||||
| 3 versus 1 | .05 | 0.05 | 0.01-0.76 | .80 | 0.04 | 0.01-0.96 | ||||||
| 4 versus 1 | .72 | 2.12 | 0.04->100 | .09 | 1.33 | 0.02-33.41 | ||||||
| 5 versus 1 | .96 | 1.49 | 0.03-85.80 | .01 | >100 | 2.48->100 | ||||||
Abbreviations: BPI, Brief Pain Inventory; chemo, chemotherapy; CI, confidence interval; HR, hazard ratio; KPS, Karnofsky Performance Status; No., number; PTV, planning target volume; SRS, stereotactic radiosurgery.
aReference is pain alone.
Bold values indicate statistical significance