A diffuse glioma with oligodendroglial-like cells and extensive calcifications

The tumor showed extensive microcalcifications and cells with oval, nuclei and a clear perinuclear halo (A), positive immunostaining for OLIG-2 (B), GFAP (C), and CD34 (D), and intermingled Neu-N-positive neurons (E). FISH revealed multiple signals for the centromere of chromosome 7 (gains) (green probe) and the EGFR locus (red probe) (F, left), and a single signal for the centromere of chromosome 10 (loss) (F, right).