Phagocytosis by neoplastic astrocytes.

ABSTRACT

Cytoplasmic accumulation of granules of hemosiderin was observed in neoplastic astrocytes related to gliomas in two patients. The first patient was a 61-year-old man who had mixed oligodendroglioma and astrocytoma of the right frontal lobe of the brain. The second patient was a 17-year-old girl who had hypothalamic astrocytoma. Granules of hemosiderin had accumulated within the cytoplasm of astrocytes in both cases. In case 2, there was also an accumulation of hemosiderin in other phagocytes. The astrocytic nature of the hemosiderin-laden cells was confirmed by immunohistochemical localization of glial fibrillary acidic protein within the cytoplasm. The term "phagocytosis" was employed because of accumulation within astrocytic perikaryon of particulate material. Review of the literature discloses that various neuroepithelial derivatives such as choroidal epithelial cells, astrocytes, neurons, and ependymal cells can perform phagocytic function as revealed by accumulation of granules of hemosiderin within their cytoplasm but this finding has seldom been described.