A giant cystic pheochromocytoma of the adrenal gland.

Adrenal pheochromocytomas are rare catecholamine-secreting tumors that originate from chromaffin cells in the adrenal medulla, and giant pheochromocytomas with cystic changes are particularly rare. We report a case of a 46-year-old man who presented with episodic hypertension and headache. Radiographic studies showed an 18-cm cystic mass in the left upper quadrant of the abdomen; further workups, which included light microscopy, immunohistochemical, and electron microscopic analysis, revealed a pheochromocytoma of the left adrenal gland. Cytogenetic analysis and genetic mutation analyses for von-Hippel-Lindau (VHL), rearranged during transfection (RET), and succinate dehydrogenase complex subunit B (SDHB) genes were also performed but failed to reveal any abnormalities within the tumor cells.