Report of two cases of large cell neuroendocrine carcinoma of duodenal ampulla with contrasting outcomes following pancreaticoduodenectomy according to the use of adjuvant chemotherapy

INTRODUCTION Large-cell neuroendocrine carcinoma (LCNEC) in the duodenal ampulla of Vater is a rare malignant tumor, with frequent postoperative recurrence and poor prognosis even following complete resection. Effective adjuvant chemotherapy is expected to offer longer survival. PRESENTATION OF CASE We present two patients with LCNEC accompanied by components of tubular adenocarcinoma/adenoma in the duodenal ampulla of Vater who underwent pancreaticoduodenectomy (PD), resulting in longer survival of 1 patient. The first patient was an 81-year-old man in whom a 14-mm protruding solid tumor of the ampulla was observed. Pylorus-preserving PD (PPPD) was performed for the diagnosis of adenocarcinoma of the ampulla, and the final histological diagnosis of the resected specimen was LCNEC with an adenoma component. The patient showed a liver metastasis 4 months after surgery and died of carcinoma after 11 months. The second patient was a 72-year-old man with a 24-mm ulcerative solid tumor of the ampulla. PPPD was also performed in this patient, and the final histological diagnosis was LCNEC with mixed adenocarcinoma component (21%). Adjuvant chemotherapy of cisplatin and etoposide was administered, and the patient survived without tumor relapse for 24 months after surgery. CONCLUSION In the surgical treatment of LCNEC of the ampulla showing malignant behaviour, an accurate preoperative diagnosis and effective adjuvant chemotherapy after curative resection are necessary for longer survival.