Transdifferentiation of Neuroendocrine Cells: Gangliocytoma Associated With Two Pituitary Adenomas of Different Lineage in MEN1.

Gangliocytomas are rare and benign neuronal cell tumors, mostly found in the hypothalamic and sellar regions. Their histogenesis is still the subject of discussions. Herein we present a unique case of a pituitary gangliocytoma associated with a prolactinoma and a corticotroph adenoma in a patient affected by MEN1. The histologic study revealed shared features between adenomatous and neuronal cells, supporting the etiological hypothesis of a common origin or a phenomenon of transdifferentiation. Furthermore, gangliocytoma could be a new tumor related to MEN1. The clinical and histologic observations are discussed and the literature on the topic is reviewed.