Table 2. Tumour characteristics of the WHO grade II gliomas included in the study (n=116).
| Parameter | Number of patients (%) |
|---|---|
| Location | |
| Frontal | 56 (48.3) |
| Temporal | 17 (14.7) |
| Parietal | 4 (3.4) |
| Occipital | 1 (0.9) |
| Central | 2 (1.7) |
| Corpus callosum | 1 (0.9) |
| Multi-lobular | 35 (30.1) |
| Histology | |
| Astrocytoma | 32 (27.6) |
| Gemistocytic astrocytoma | 11 (9.5) |
| Oligoastrocytoma | 34 (29.3) |
| Oligodendroglioma | 39 (33.6) |
| Largest diameter (cm) | |
| <6 | 84 (72.4) |
| ⩾6 | 32 (27.6) |
| Contrast enhancement | |
| Yes | 52 (44.8) |
| No | 64 (55.2) |
| Crossing midline | |
| Yes | 34 (29.3) |
| No | 82 (70.7) |
| PROX1 expression (% positive cells) | |
| <10% | 76 (65.5) |
| 10–30 | 24 (20.7) |
| >30 | 16 (13.8) |
| Mutated IDH1 protein | |
| Yes | 90 (77.6) |
| No | 26 (22.4) |
| LOH 1p/19q | |
| Yes | 33 (28.4) |
| No | 83 (71.6) |
Abbreviations: IDH1=isocitrate dehydrogenase 1; LOH=loss of heterozygosity.