Pineoblastoma

What it means

Pineoblastoma is a rare primitive neuroectodermal tumor (PNET) arising in the pineal gland. Pineoblastomas are classified as a WHO grade IV tumor and comprise one-fourth to one-half of pineal parenchymal tumors. Pineoblastoma is a highly cellular tumor originating in the pineal gland and containing small, poorly differentiated cells.

Pineoblastomas are rare, malignant, pineal region lesions that account for <0.1% of all intracranial tumors. Pineoblastomas harbor a poor prognosis and can metastasize along the neuroaxis. Although they typically appear radiographically as a focal enhancing mass, pineoblastomas can be locally invasive and spread outside the pineal region through the subarachnoid space. Pineoblastomas are more common in children than in adults, and adults account for <10% of patients.

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Pinealoblastoma