Other Embryonal Tumors

Central neuroblastoma (grade 4), an early childhood malignant tumor, occurs in the cerebral hemispheres. Histologically, it is composed of immature cells in various stages of neuronal differentiation.

Medulloepithelioma (grade 4), a rare malignant tumor of neonates and young children, occurs in the cerebrum, cerebellum, and brainstem. Grossly, this well-circumscribed tumor is soft and pinkish-gray, with hemorrhages and necrosis. Histologically, primitive epithelial cells are arranged in a tubular or papillary fashion that resembles the epithelial lining of the embryonic neural tube.

Ependymoblastoma (grade 4), a rare malignant tumor of neonates and young children, occurs in the cerebral hemispheres. Grossly, it is circumscribed, gray-pink, and moderately firm. Histologically, it is densely cellular with small cells forming rosettes around lumens. Mitoses are frequent. The cells may invade the leptomeninges.

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