Walsh & Hoyt: Tumors of Pineal Parenchymal Cells

Pineal parenchymal cells are neuroectodermal in origin. Tumors arising from pineal parenchymal cells are called pinealomas and are traditionally divided into two types. Pineoblastomas are composed of immature undifferentiated cells that are sometimes classified with primary neuroectodermal tumors (PNETs). Pineocytomas are more differentiated tumors in which the cells are similar to the normal cells that are present in the mature pineal gland. Some authors also recognize an intermediate form of pinealoma that contains both mature and immature cells.