Which among the following is the most common site of ectopic phaeochromocytoma?
High-Yield Explanation
Almost all pheochromocytomas (about 90%) occur in the abdomen, and most of these (85%) are in the adrenal medulla. Extra-adrenal pheochromocytomas (including sympathetic and parasympathetic paragangliomas) are found in the perirenal area, the organ of Zuckerkandl, the urinary bladder, the hea, the neck, and the posterior mediastinum. Extra-adrenal pheochromocytomas account for 10% of all pheochromocytomas in adults and 30-40% of pheochromocytomas in children. They are usually larger than adrenal pheochromocytomas. Ref: Else T., Hammer G.D., McPhee S.J. (2010). Chapter 12. Disorders of the Adrenal Medulla. In S.J. McPhee, G.D. Hammer (Eds), Pathophysiology of Disease, 6e.