Sporadic type composite pheochromocytoma with neuroblastoma:: Clinicomorphologic, DNA content, and ret gene analysis

Composite pheochromocytomas (CP) account for only 3% of all pheochromocytomas. We analyzed the clinical, immunohistochemical, ultrastructural, DNA content, and a 634 ret mutation feature in a 56-yr-old Mexican woman with a CP localized in the right adrenal gland and associated with a blood pressure of 140/90 mmHg. Clinical symptoms were absent after surgery. The tumor showed pheochromocytoma and neuroblastoma components. This dual phenotype was supported by light microscopy and corroborated by immunohistochemistry and ultrastructural findings. Flow cytometric analysis showed that both components were diploid. A genetic mutational analysis of the ret oncogene in exon 11 showed no 634 mutation. This case demonstrates the indolent behavior of neuroblastoma associated with a sporadic-type CP in an adult patient.