paraganglioma
Pronunciation: pair-ah-GANG-glee-oh-mah
A neuroendocrine tumor arising from paraganglia, characterized by nesting pattern and chromaffin reaction.
Full Definition
Paraganglioma is a neuroendocrine tumor that arises from paraganglia (extra-adrenal chromaffin tissue) distributed throughout the body. In the central nervous system, these tumors most commonly occur at the jugulotympanic region and carotid body. Histologically, they show a characteristic 'Zellballen' or nesting pattern with clusters of chief cells surrounded by sustentacular cells. The chief cells contain catecholamine-producing granules and are positive for chromogranin and synaptophysin, while sustentacular cells are positive for S-100 protein. Paragangliomas may be associated with hereditary syndromes and can rarely undergo malignant transformation.
Usage
Usage note: Zellballen pattern is pathognomonic; consider hereditary syndromes in young patients or those with family history.
In Context
- "The jugulotympanic mass showed typical Zellballen pattern with chromogranin-positive chief cells consistent with paraganglioma." — Head and neck pathology report
- "Genetic testing was recommended given the family history and paraganglioma diagnosis." — Oncology consultation note