Composite Carcinoma-Carcinoid Tumor of the Common Bile Duct: A case report

ABSTRACT

The occurrence of a carcinoid admixed with an adenocarcinoma of the gastrointestinal tract is an unusual phenomenon which has been reported in the esophagus, stomach, gallbladder, colon, and appendix. Herein, we describe an extremely rare case of a composite tumor of the common bile duct. A 50-year-old woman who suffered from right upper abdominal pain and jaundice was found on radiographical investigations and operation to have a tumor in the common bile duct. Histopathologically, the resected tumor was composed mainly of solid nests of atypical round cells and partially of a well-differentiated adenocarcinoma showing a mutual transition in the mucosal layer. Both immunohistochemical and ultrastructural analyses confirmed a composite tumor: a neuroendocrine cell carcinoma and a tubular adenocarcinoma.