label: Ampulla of Vater Large Cell Neuroendocrine Carcinoma
label_lc: ampulla of vater large cell neuroendocrine carcinoma
description: An aggressive high-grade carcinoma with neuroendocrine differentiation that arises from the ampulla of Vater and is composed of malignant large cells. The mitotic count is more than 20 per 2 mm2 and/or the Ki-67 index is more than 20%.