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.). The disease is pineal parenchymal cell neoplasm (MONDO_0024890). Also known as: neoplasm of pineal gland, neoplasm of the pineal gland, pineal gland neoplasm, pineal gland tumor, pineal gland tumour, pineal parenchymal cell tumor, pineal parenchymal cell tumour, pineal parenchymal neoplasm.