Primary malignant hepatic pheochromocytoma with negative adrenal scintigraphy

A 60-year-old male patient with hypertension was referred to our hospital because of insufficient blood pressure control (190/98 mmHg) and to rule out secondary hypertension. A computed tomography scan revealed no adrenal tumor but a large liver mass (5 x 5 cm), and magnetic resonance imaging showed a high signal intensity lesion on the T2-weighted image. Twenty-four hour urinary excretion of catecholamine metabolites was markedly increased, although a 123I-metaiodobenzyl guanidine (MIBG) scintigram failed to show accumulation in the hepatic mass, and no difference was noted between the catecholamine concentration in the tumor-drainage vein and that obtained from the vein draining from the non-tumor area. Liver biopsy did show features compatible with pheochromocytoma (i.e., chromogranin A-positive cells). Transcatheter arterial embolization of the liver tumor was conducted and resulted in a marked (50%) decrease in the 24-h urine normetanephrine excretion. Several metastatic foci were noted in the spinal bone and transcatheter arterial embolization (TAE) was also conducted with successful results. Thus, we experienced a case of primary malignant hepatic pheochromocytoma with negative 123I-MIBG scanning.