American Urological Association - Pheochromocytoma (Adrenal Paraganglioma)
Pheochromocytoma (Adrenal Paraganglioma)
- Occurs 70% in adrenal gland and 30% are extra-adrenal in location.
- 10% are familial and usually bilateral and multifocal.
- Occurs mostly in adults; rare in children.
- Clinical: Classically associated with paroxysmal sweating attacks, headaches, and tachycardia; hypertension may be intermittent or sustained; these tumors may secrete epinephrine and/ or norepinephrine, ACTH, or parathormone; urinary vanillylmandelic acid (VMA) is elevated in up to 90% of cases.
- Gross: encapsulated yellow-white to red-brown, soft, fleshy tumor (image A).
- Well-defined nests (zellballen) of polygonal cells surrounded by a delicate fibrovascular stroma
(image B) & (image C).
- Cells have considerable variation in size and shape, and often demonstrate faintly basophilic (blue) finely granular cytoplasm.
- Pleomorphism, hyperchromasia, and mitotic figures may be present and do not necessarily indicate malignancy (image D).
- Eosinophilic globules (PAS positive) can be seen.
- The only definitive evidence of malignancy is metastatic disease.
- Immunohistochemistry: synaptophysin+, chromogranin+ and S100+ (+ only in sustentacular cells intermingled with malignant chromaffin cells).