Pheochromocytoma associated with arterial fibromuscular dysplasia.

An unusual case of pheochromocytoma associated with multifocal medial fibromuscular dysplasia of the left subclavian (ruptured), celiac, and bilateral renal arteries is described. Additionally, the coronary arteries, left renal arcuate vessels, and peripancreatic and intracolonic muscular arteries revealed intimal fibroplasia. Thirty-three cases of pheochromocytoma associated with renal artery stenosis have been reported, including four instances radiologically attributed to fibromuscular dysplasia. Renal artery fibromuscular dysplasia associated with pheochromocytoma has not been histologically documented, and extrarenal fibromuscular dysplasia with simultaneous pheochromocytoma has not been previously described. Current etiologic concepts of fibromuscular dysplasia and possible pathogenetic mechanisms for its occurrence with pheochromocytoma are discussed.