Table 3.
Univariate and multivariate Cox proportional hazard analyses of prognostic factors for local recurrence-free survival of spinal chordoma patients
| Factors | Categories | Univariate analysis | Multivariate analysis | ||
|---|---|---|---|---|---|
|
| |||||
| χ2 | p-value | p-value | HR (95% CI) | ||
| Sex | Male/Female | 2.949 | 0.086 | ||
| Age | ≤ 50/> 50 | 6.560 | 0.010 | 0.25 | 1.693 (0.686-4.177) |
| Tumor size | ≤ 5 cm/> 5 cm | 0.278 | 0.59 | ||
| Tumor location | Sacral vertebra/Cervical or thoracic or lumbar vertebra | 0.003 | 0.95 | ||
| Preoperative recurrence | Yes/No | 0.954 | 0.32 | ||
| Surrounding muscle invasion | Yes/No | 24.585 | < 0.001 | 0.003 | 3.660 (1.544-8.675) |
| Grade | High/Low | 0.231 | 0.631 | ||
| Stage | IA/IB/IIA/IIB/III | 0.960 | 0.916 | ||
| Type of resection | EI/EA | 16.472 | < 0.001 | 0.30 | 1.607 (0.645-4.004) |
| Tumor hemorrhage | Yes/No | 4.031 | 0.045 | 0.430 | 1.523 (0.536-4.329) |
| Tumor necrosis | Absent/mild/moderate/severe | 0.189 | 0.97 | ||
| Extent of TILs | Negative/Positive | 4.104 | 0.043 | 0.93 | 1.034 (0.472-2.263) |
| Ki-67 index | High/Low | 14.163 | < 0.001 | 0.002 | 3.806 (1.627-8.907) |
| PD-1 expression on tumor cells | Negative/Positive | 3.406 | 0.065 | ||
| PD-L1 expression on tumor cells | Negative/Positive | 1.035 | 0.30 | ||
| PD-1 expression in TILs | Negative/Positive | 10.051 | 0.002 | 0.391 | 1.537 (0.576-4.102) |
| PD-L1 expression in TILs | Negative/Positive | 8.792 | 0.003 | 0.033 | 0.298 (0.098-0.907) |
EI, Enneking inappropriate; EA, Enneking appropriate; TILs, tumor-infiltrating lymphocytes; PD-1, programmed cell death 1; PD-L1, programmed cell death-1 ligand 1; HR, hazard ratio; CI, confidence interval.