Table 4.
Unadjusted and adjusted analyses on overall survival in 33 patients diagnosed with butterfly glioblastoma between 01/01/2007 and 31/12/2014
| Variable | Unadjusted | Adjusted for sex, age, and KPS | ||
|---|---|---|---|---|
| HR (95% CI) | P value | HR (95% CI) | P value | |
| Sex | ||||
| Male | Ref. | Ref. | ||
| Female | 0.74 (0.36–1.52) | .41 | 0.74 (0.36–1.54) | .42 |
| Age (per year) | 1.06 (1.03–1.10) | .001 | 1.06 (1.02–1.10) | .003 |
| KPS | ||||
| ≥70 | Ref. | Ref. | ||
| <70 | 2.96 (1.21–7.21) | .017 | 1.86 (0.73–4.74) | .19 |
| Tumor side | ||||
| Left | Ref. | Ref. | ||
| Right | 1.28 (0.57–2.86) | .56 | 1.51 (0.63–3.59) | .35 |
| Equal | 1.95 (0.75–5.05) | .17 | 1.77 (0.64–4.91) | .27 |
| Main tumor location | ||||
| Frontal lobe | Ref. | Ref. | ||
| Temporal lobe | 3.59 (1.11–11.65) | .034 | 1.32 (0.31–5.70) | .71 |
| Occipital lobe | 1.59 (0.56–4.52) | .39 | 1.70 (0.58–4.98) | .33 |
| Parietal lobe | 0.43 (0.05–3.43) | .42 | 0.99 (0.11–9.03) | 1.00 |
| Deep-seated | 6.69 (1.84–24.35) | .004 | 4.58 (1.15–18.20) | .031 |
| MRI T1 volume (per cm3) | 1.00 (0.99–1.01) | .68 | 1.00 (0.99–1.02) | .56 |
| MRI T2/FLAIR volume (per cm3) | 1.00 (1.00–1.01) | .33 | 1.00 (1.00–1.01) | .15 |
| T2/FLAIR:T1 ratio (per unit) | 1.01 (0.88–1.16) | .90 | 0.95 (0.79–1.14) | .58 |
| Hypothalamus involvement | 2.02 (0.95–4.32) | .07 | 1.36 (0.63–2.93) | .44 |
| Basal ganglia involvement | 1.63 (0.79–3.35) | .19 | 1.23 (0.54–2.83) | .62 |
| Blood vessel involvement | 0.57 (0.27–1.19) | .13 | 0.94 (0.40–2.23) | .89 |
| Mass effect (per mm midline shift) | 0.95 (0.87–1.04) | .24 | 0.98 (0.89–1.08) | .67 |
| Necrosis | 0.64 (0.24–1.71) | .38 | 0.37 (0.13–1.06) | .06 |
| Flow void | 0.64 (0.29–1.41) | .27 | 0.97 (0.40–2.35) | .95 |
| MGMT promoter methylation status | ||||
| Unmethylated | Ref. | |||
| Methylated | 0.29 (0.04–2.42) | .25 | 0.06 (0.00–3.33) | .17 |
| Primary treatment | ||||
| Two or three modalities | Ref. | Ref. | ||
| One modality | 2.37 (0.95–5.96) | .07 | 1.67 (0.43–6.51) | .46 |
| Best supportive care | 8.10 (2.65–24.79) | < .001 | 5.11 (1.09–23.89) | .038 |
HR, 95% CI and P-values calculated by unadjusted and adjusted Cox proportional hazards regression. Deep-seated location defined as tumor mainly located in thalamus, basal ganglia, capsula interna, splenium corpus callosum, or mesencephalon. Tumor volumes in cm3. Mass effect measured as midline shift in millimeters (mm). Volumes defined as contrast-enhancing tumor volume in T1-weighted MRI and tumor-associated non-enhancing hyperintense lesion in T2-weighted/FLAIR MRI. Only patients with conclusive result were included in MGMT analyses (n = 9). Treatment modalities included surgical resection, radiation therapy, and temozolomide concurrent and/or adjuvant. P-values < .05 were considered statistically significant.
HR, hazard ratio; CI, confidence interval; KPS, Karnofsky performance status; MRI, magnetic resonance imaging; FLAIR, fluid attenuated inversion recovery; MGMT, O(6)-methylguanine-DNA methyltransferase.