We present two cases of composite adrenal pheochromocytoma-ganglioneuroma tumours, and review the literature of this uncommon pathologic entity.
Case 1
A 58 year old lady with abdominal pain has a 4.5 cm lesion of the right adrenal gland detected on ultrasound and adrenal CT. Other symptoms were fever, sweating, severe anxiety and occasional nausea. Fasting plasma metanephrines were twice the upper limit of normal at 810 & 880 pmol/L (normal <447). An MIBG scan showed focal avidity in the right upper quadrant, with no abnormal uptake associated with the left adrenal gland.
She was given pre-operative alpha blockade and underwent laparoscopic adrenalectomy. Histopathology showed a composite pheochromocytoma-ganglioneuroma tumour with a minor component of pheochromocytoma and a major component of ganglioneuroma.
Case 2
A 76yo man with Neurofibromatosis (NF-1) presents with a radiculopathy due to a pathological fracture of his L3 vertebrae. There was no history of palpitations, headache, diaphoresis or pallor, and throughout his hospital admission he was predominantly normotensive. A CT of his chest/abdomen/pelvis identified a 9 cm right adrenal mass. His fasting plasma metanephrines were normal, but his plasma normetanephrines were mildly raised at 0.95 nmol/L (normal < 0.90). Biopsy of his L3 vertebra was consistent with a neuroendocrine tumour.
He was commenced on alpha blockade and underwent laparoscopic adrenalectomy. Histopathology was consistent with a composite tumour of pheochromocytoma and ganglioneuroma, with extra-adrenal extension.
Discussion
Most pheochromocytomas are composed predominantly of chromaffin cells, whilst 3% of cases are associated with other tumours1. Where the other cell type is derived from the neural crest, the term “composite pheochromocytoma” is used1. The associated tumours are usually ganglioneuromas, malignant schwannomas, and neuroendocrine carcinomas1.
Signs and symptoms of composite pheochromocytoma relate to secretion of catecholamines and their metabolites, with rare exceptions1. However, some patients are normotensive with no symptoms of catecholamine excess2.