This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Disorders of Adrenal Gland, Subject name: Medicine
All are true about pheochromocytoma except? 
Select and explain. 
A. Urinary V.M.A is most specific, B. Paraganglioma occurs at skull base, C. 10% extra adrenal, D. Organ of Zuckerkandl is most common extra adrenal site
A: Urinary V.M.A is most specific
Answer: A: Urinary V.M.A is most specific 
Explanation: Paraganglioma is a term used to describe catecholamine producing tumors in the skull base and neck. The classic rule of tens is valid for pheochromocytoma. Organ of Zuckerkandl is a collection of chromaffin cells near the origin of the inferior mesenteric aery or near the aoic bifurcation. It is the most common extra-adrenal site of pheochromocytoma. Urinary VMA is used for diagnosis of neuroblastoma and not pheochromocytoma. The most sensitive test for pheochromocytoma is urinary fractionated metanephrine