Adrenocortical Carcinoma Mimicking Pheochromocytoma: A case Report and Review of Literature

Adrenocortical carcinoma (ACC) is an uncommon malignancy originating from cortex of adrenal gland. The most common pitfall in diagnosis of ACC is to distinguish it from pheochromocytoma. Here we report a 62-year-old hypertensive man with presentation of dyspnea. The laboratory data showed an increase in urine cortisol and renin with a mild increase in aldosterone, but decrease in adrenocorticotropic hormone. Computerized tomography (CT) scanning revealed heterogeneous mass with enhancement in the adrenal region. The patient underwent surgery with an empirical diagnosis of pheochromocytoma, whereas ACC with high mitotic rate of about 50 mitoses/50 high-power field with vascular invasion was reported on histopathology. Immunohistochemistry was positive for Vimentin, Inhibin-α, Melan-A, and Synaptophysin. Ki-67 was positive in 25% of tumor cells. The results confirmed the diagnosis. ACC should be considered in differential diagnosis of adrenal masses especially in cases of hypertension and Cushing syndrome.