Table 4.
Prognostic factors.
| Variables | Bivariate analyses | Multivariate analyses | ||
|---|---|---|---|---|
| HR (95% CI) | P value | HR (95% CI) | P value | |
| Age | 1.04 (1.01–1.05) | P < 0.001 | Not significant | |
| KPS (≤80 versus >80) | 2.59 (1.55–4.3) | P < 0.001 | 2.08 (0.28–0.83) | P = 0.008 |
| RPA | ||||
| IV versus III | 2.39 (1.18–4.82) | P = 0.015 | 3.46 (1.61–7.46) | P = 0.001 |
| V versus III | 6.32 (2.82–14.14) | P < 0.001 | 7.29 (3.23–16.34) | P < 0.001 |
| Histology (GBM versus AA) | 2.45 (1.53–3.94) | P < 0.001 | 3.13 (1.79–5.48) | P < 0.001 |
| Tumour volume | 1.04 (1.01–1.07) | P = 0.005 | Not significant | |
| Treatment volume | 1.03 (1.01–1.06) | P = 0.013 | ∗ | |
| Margin to PTV | ||||
| 0 versus ≥1 | 0.77 (0.67–0.87) | P < 0.001 | 3.19 (1.91–5.31) | P < 0.001 |
*This variable was not considered for the multivariate analyses because of the strong correlation (0.97 Spearman' s correlation coefficient) with tumour volume.