Neuroendocrine carcinoma arising from Barrett's esophageal adenocarcinoma: a case report.

Neuroendocrine carcinoma in Barrett’s esophagus is rare and its developmental mechanisms remain unclear. Neuroendocrine carcinoma arising in Barrett’s esophagus with adenocarcinoma was detected at an early stage and resected by endoscopic submucosal dissection. Detailed pathological examination revealed that the neuroendocrine carcinoma originated via differentiation of the preexisting adenocarcinoma. A 79-year-old man presented with a flat protruding lesion in the esophagogastric junction. Esophagogastroduodenoscopy revealed a red flat 10-mm protruding lesion in the Barrett’s epithelium and a shallow depression at the distal end. Narrow band imaging with magnification showed that the blood vessels in the protrusion were dilated and meandered irregularly, while those in the depression were small and did not form a network; the blood vessels were missing in some parts of the depression. Well-differentiated adenocarcinoma was diagnosed after analysis of the biopsy specimen of the protrusion, and endoscopic submucosal dissection was performed. The pathological diagnosis was neuroendocrine carcinoma with an adenocarcinoma component.