Central neurocytoma with malignant course. Neuronal and glial differentiation and craniospinal dissemination.

Central neurocytoma is a benign neuronal tumor of young adults in the lateral cerebral ventricles with characteristic X ray and light microscopic findings. In many respects typical central neurocytoma is reported below, with recurrence in the third month requiring reoperation. Death ensued in the fifth postoperative month. Subsequent histology proved progressive vascular proliferation and increasing, unusual glial differentiation of the neuronal tumor. At autopsy tumorous seeding blocked the liquor circulation. A thin tumorous layer covered the surface of all ventricles, the cerebellum and medulla oblongata. The GFAP positive cells out-numbered the synaptophysin positive ones. Increase of GFAP positivity and vascular proliferation of the central neurocytoma may be alarming signs suggesting a malignant course in addition to the other atypical features.