Neuroblastoma IV-S followed by extra-adrenal pheochromocytoma 15 years later.

Common origin of sympathoblasts and pheochromoblasts from the neural crest cells is generally accepted. Neuroblastoma and pheochromocytoma result from an abnormal proliferation of these committed cells. They are included in the group of neuroendocrine neoplasms, formerly named Apudomas. Previous reports of mixed tumours of neuroblastoma and pheochromocytoma, and ganglioneuroma and pheochromocytoma, support this hypothesis. A case of extra-adrenal pheochromocytoma in an adolescent who 15 years before was successfully treated for a stage IV-S neuroblastoma without evidence of primitive tumour is reported. Two hypothesis are formulated: (1) the second neoplasm may have arisen from the unlocated primitive tumour, probably silent evolution could be due to its maturation into ganglioneuroma-pheochromocytoma; (2) taken into account a common origin of both neoplasms, the patient may have a genetic predisposition to develop neuroendocrine tumours. Whatever the mechanism, second neoplasms, as the case reported, late relapses, and late toxic effects may justify long follow-up of neuroblastoma survivors.