Adenosquamous carcinoma of the liver arising in biliary cystadenocarcinoma: clinical, radiologic, and pathologic features with review of the literature.

Primary biliary cystadenoma, cystadenocarcinoma, squamous carcinoma, and adenosquamous carcinoma of the liver are rare tumors. We describe a middle-aged woman with recurrent fever and a clinical diagnosis of hepatic abscess who proved at laparotomy to have adenosquamous carcinoma of the liver arising in a biliary cystadenocarcinoma. The pathologic features of the tumor and findings on ultrasonography, angiography, and computed tomography are described in detail. The pathogenetic relationships of this unusual tumor to chronic biliary inflammation, biliary cystadenoma, and cystadenocarcinoma and to bile duct malformations (von Meyenburg complexes) are considered.