Figure 3.

Additional representative high‐grade gliomas with neuroblastic (PNET‐like) foci, including (A–C): a GBM‐PNET that developed from progression of a diffuse astrocytoma. A. Diffuse astrocytoma, World Health Organization grade II diagnosed in a 30‐yo woman. B. A recurrence 4 years later showed the emergence of a PNET‐like component with neuroblastic rosettes comprising the majority of the tumor. C. Anaplastic foci were also noted. Two additional examples of the relatively sharp interface between the malignant glioma (left) and the PNET‐like nodules (right) are shown in (D) and (E). Medulloblastoma‐like nodularity from another GBM‐PNET is shown in (F). Abbreviations: GBM = glioblastoma; PNET = primitive neuroectodermal tumor.