Esophageal collision tumor (Large cell neuroendocrine carcinoma and papillary carcinoma) arising in a Barrett esophagus.

Abstract We report herein a unique case of an esophageal collision tumor composed of a papillary adenocarcinoma and a large cell neuroendocrine carcinoma arising in a Barrett esophagus. Hematoxylin-eosin and silver staining patterns, immunohistochemistry, and electron microscopy of the large cell neuroendocrine component are discussed.