A 45 year old male was evaluated for secondary hypeension & was diagnosed with pheochromocytoma. MRI abdomen revealed a 3 cm mass in left adrenal gland. He underwent a left adrenalectomy. After this, his hypeension is well controlled. How will you decide whether his pheochromocytoma was malignant?
High-Yield Explanation
About 5-10% of pheochromocytomas are malignant. Cellular atypia, presence of mitoses, and invasion of vessels are insufficient for the diagnosis of malignant pheochromocytoma. 123I-metaiodobenzylguanidine (MIBG) scans are useful in locating distant metastases. The absence of distant metastases rules out malignant disease. Malignant pheochromocytomas are tumors with lymph node or distant metastases (lungs, bone, or liver)