Astrocytic characteristics of oligodendroglioma. Fine structural and immunohistochemical studies of two cases.

Two oligodendrogliomas were studied by light and electron microscopy. Additionally, an immunohistochemical study for glial fibrillary acidic protein (GFAP) was carried out. Some tumor cells exhibited glial filaments and perivascular end-feet, as on the one hand is characteristic of astrocytes, and glycogen granules and zonulae adherents which on the other hand are often seen in astrocytes but rarely in oligodendrocytes. Tumor cells with or without astrocytic characteristics showed the common fine structures and appeared to be on the same cell line. Our fine structural and immunohistochemical findings suggest that oligodendroglioma cells are of an astrocytic nature.