Composite Gangliocytoma/Neuroma and Neuroendocrine Tumor

**Semantic type:** Neoplastic Process

**Definition:** A usually indolent neuroendocrine neoplasm that almost exclusively arises in the second part of the duodenum. Rare sites of involvement include jejunum, pylorus, appendix, thymus, and lung. It is a triphasic tumor consisting of a mixture of epithelioid neuroendocrine cells, Schwann-like cells, and ganglion cells.

**Synonyms:** - CoGNET - Gangliocytic NET - Gangliocytic Neuroendocrine Tumor - Gangliocytic Paraganglioma - MiGNeN