Pineal parenchymal cell neoplasm

A neoplasm arising from the pineocyte, a cell with photosensory and neuroendocrine functions. It may be composed of mature elements or primitive, immature cells. The cellular composition determines the biological behavior and clinical outcome. Three types are recognized: pineoblastoma, pineocytoma, and pineal parenchymal tumor of intermediate differentiation (Adapted from WHO.)