PNET
Also written as: PNET — Primitive Neuroectodermal Tumor
Primitive neuroectodermal tumor, a group of aggressive brain tumors affecting children and young adults.
Full Definition
Primitive neuroectodermal tumor (PNET) refers to a group of highly malignant embryonal tumors arising from primitive neuroectodermal cells. In current WHO classification, many tumors previously called PNETs are now classified more specifically, such as medulloepithelioma or embryonal tumor with multilayered rosettes. CNS PNETs typically occur in children and young adults, most commonly in the cerebral hemispheres. These tumors are highly aggressive with tendency for CSF dissemination and generally poor prognosis despite intensive multimodal therapy including surgery, radiation, and chemotherapy.
Usage
Usage note: Classification has evolved; verify current WHO terminology for specific tumor types.
In Context
- "MRI showed a large frontal PNET with evidence of leptomeningeal spread." — Radiology report
- "The 2016 WHO classification reclassified many tumors previously diagnosed as PNET." — Pathology consultation