Adenosquamous Carcinoma of the Gallbladder with Osteoblast Formation and Involvement of the Bile Duct

We describe an adenosquamous carcinoma of the gallbladder in a 40 year old male presenting with obstructive jaundice secondary to a bile duct stricture. The bile duct adjacent to the gallbladder was involved solely with adenocarcinoma and this was confirmed with immunohistochemistry using antibodies to ca 19.9. ca 125 and CEA. We postulate that only the adenocarcinoma component of the primary tumour invaded the epithelium of the adjacent bile duct. This led to the progression and involvement of the adjacent bile duct epithelium by the adenocarcinoma component only.