Mixed neuroendocrine-non-neuroendocrine neoplasms of the ampulla of Vater: A case report and literature review

Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) of the ampulla of Vater are extremely rare. We present a case of a MiNEN of the ampulla of Vater and review the literature related to management and treatment recommendations. A 72-year-old woman presented with Charcot's triad for a week. Computed tomography revealed a periampullary tumor. Endoscopic retrograde cholangiopancreatography with internal drainage and sphincterotomy with biopsy revealed mixed adenocarcinoma-neuroendocrine carcinoma. Ampullary MiNEN with an American Joint Committee on Cancer (8th edition) TNM classification of Stage IIIA T3bN1M0 was diagnosed, and the Whipple procedure was performed. Both components of the tumor were of high grade, each component accounting for approximately 50% of the tumor. FOLFOX (oxaliplatin + de Gramont) was prescribed as adjuvant chemotherapy. No recurrence was noted at the 3-month follow-up. Diagnosis of MiNENs through biopsies is challenging, and core biopsies should be suggested when a surgical sample is unavailable. Although heterogeneous, MiNENs are usually highly aggressive neoplasms, contributing to the dissemination of metastases and poor prognosis. In conclusion, radical resection is the optimal treatment choice for almost all potentially curable cases. In addition, treatment strategies for patients with a new diagnosis of MiNENs of the ampulla of Vater should be formulated after discussions in multidisciplinary meetings and should be based on the most aggressive and predominant component in the diagnostic sample.