Table 2.
Univariate and Multivariate Analysis of PFS in GBM patients.
| Variable | Univariate Analysis | Multivariate Analysis | ||||
|---|---|---|---|---|---|---|
| Hazard Ratio | 95% CI | p-Value | Hazard Ratio | 95% CI | p-Value | |
| Age (yrs) | 1.017 | 1.008–1.027 | 0.000 | 1.015 | 1.006–1.024 | 0.002 |
| Sex | ||||||
| Male | 1 | |||||
| Female | 0.851 | 0.687–1.054 | 0.140 | |||
| Side | ||||||
| Left | 1 | |||||
| Right | 1.091 | 0.889–1.339 | 0.404 | |||
| Tumor Site | ||||||
| Precentral | 1 | |||||
| Retrocentral | 1.045 | 0.811–1.347 | 0.733 | |||
| Temporal + Insular | 1.031 | 0.810–1.312 | 0.806 | |||
| Radiological Features | ||||||
| Ependymal involvement (yes vs no) | 1.114 | 0.893–1.390 | 0.338 | |||
| Corpus Callosum involvement (yes vs no) | 0.917 | 0.737–1.142 | 0.439 | |||
| Necrotic-cystic component (yes vs no) | 0.974 | 0.781–1.215 | 0.816 | |||
| Midline shift (yes vs no) | 0.979 | 0.797–1.202 | 0.838 | |||
| Preoperative Tumoral Volume computed on postcontrast T1-weighted images, cm3 | 1.003 | 0.999–1.008 | 0.170 | |||
| Preoperative Tumoral Volume computed on T2-weighted images, cm3 | 0.996 | 0.994–0.998 | 0.000 | 0.999 | 0.996–1.001 | 0.311 |
| Preoperative ΔT1/T2 MRI Index | 1.016 | 1.012–1.020 | 0.000 | 1.011 | 1.005–1.016 | 0.000 |
| Residual tumor, cm3 | 1.083 | 1.067–1.100 | 0.000 | 0.977 | 0.943–1.013 | 0.208 |
| EOR (continuous variable) | 0.949 | 0.942–0.957 | 0.000 | 0.948 | 0.935–0.961 | 0.000 |
| EOR (categorical variable) | ||||||
| EOR = 100% | 1 | |||||
| 99% ≤ EOR ≤ 90% | 1.622 | 1.254-2.098 | 0.000 | |||
| 89% ≤ EOR ≤ 80% | 2.425 | 1.783-3.298 | 0.000 | |||
| EOR ≤ 79% | 5.245 | 3.854-7.138 | 0.000 | |||
| Biological Features | ||||||
| MGMT promoter methylation (yes vs no) | 0.639 | 0.518-0.787 | 0.000 | 0.673 | 0.544-0.833 | 0.000 |
| IDH 1/2 mutation (yes vs no) | 0.706 | 0.488-1.023 | 0.066 | 0.894 | 0.612-1.305 | 0.561 |
| Ki67 | 1.000 | 0.995-1.006 | 0.873 | |||
Table showing the influence of different factors on the PFS rates as per univariate survival analysis and multivariate analysis on the entire GBM patients cohort. (p-value < 0.05 at Log-rank test). Boldfacing values represent statistical significant results (p < 0.05). CI = confidence interval; p-value = level of marginal significance; MRI = magnetic resonance image; preoperative ΔT1/T2 MRI Index = ratio between pre-operative tumoral volume on postcontrast T1-weighted and T2 weighted images; EOR = extent of resection; CWs = Carmustine Wafers; RT = radiotherapy; CT = chemoteraphy; MGMT = O6-methylguanine-DNA methyl-transferase; IDH = isocitrate dehydrogenase; OS = overall survival.