Fig. 2.

Histological and immunohistochemical findings. In H&E stained sections, mildly to highly pleomorphic glial tumor cells with glial cell processes and hemorrhages were detected (a). Calcifications and very round tumor cells with only short processes and perinuclear halos (b), intermingled within neuronal cells showing dysmorphic appearance, were also visible (c). Immunohistochemistry showed tumor cells being positive for GFAP (d) with retained ATRX expression (e), and no expression of IDH1 R132H mutant protein (f). Tumor cells were negative for EMA (g). Ganglionic cells were positive for synaptophysin (h) and there were some CD34 positive tumor cells (i). Histone H3.3 K27M mutant protein was strongly expressed in the nuclei of tumor cells (j). Ki67 index showed 20% positive cells (k) and there were some PHH3 (H3S10p) positive cells (l). Magnification: a: 10 ×, b: 20 ×, c–l: 40 ×