Adenosquamous Carcinoma of the Distal Common Bile Duct: A Case of a Rare Type of Cholangiocarcinoma.

INTRODUCTION

Adenosquamous carcinoma (ASC) is a rare subtype of the conventional adenocarcinoma of the bile duct. The clinico-pathological characteristics of this entity are poorly understood partly due to its rarity.

CASE SUMMARY

A 67-year-old ASA II male presented with obstructive jaundice subsequently complicated by cholangitis. CT abdomen showed dilatation of the intra and extrahepatic biliary tree. Endoscopic retrograde cholangiopancreatography revealed a stricture with a mucosal growth at the ampulla of Vater. He had a pancreaticoduodenectomy and the distal common bile duct tumour identified in the specimen was on histology an adenosquamous carcinoma (ASC) of the extrahepatic bile duct.

DISCUSSION

ASCs are considered to have more aggressive tumour biology compared to adenocarcinomas. The presence of a squamous component at the invasive front relates to its poor prognosis. Surgery is the curative option, but with a high propensity for early recurrence and distant metastases. The scarcity of reports on the clinicopathological course of ASC have resulted in a lack of standardised care pathways.

CONCLUSION

A better understanding of the clinicopathological characteristics, biological behaviour and disease progression of ASC will aid therapeutic options and prognostication.