[An aggressive neuroendocrine carcinoma arising from the ampulla of Vater. Morphologically, it is characterized by the presence of small malignant cells, necrosis, and a high mitotic rate. Signs and symptoms include jaundice, abdominal pain, anorexia, nausea, vomiting, and weight loss. ( NCI )]
UMLS (NCI) C1332250Ampullary Small Cell Carcinoma