Context The neuroendocrine tumor of the ampulla of Vater represents a rare disease and, although the majority of them are indolent, this neoplasm has a relatively poor prognosis. A quarter of cases of ampullary neuroendocrine tumors have been detected in patients with neurofibromatosis type I (von Recklinghausen's disease). The biological behavior of ampullary neuroendocrine tumor shows no asso...