All of the following are associated with Caroli's disease, EXCEPT:

Caroli's disease is a syndrome of congenital ductal plate malformations of the intrahepatic bile ducts and is characterized by segmental cystic dilatation of the intrahepatic biliary radicals. Caroli's disease also is associated with an increased incidence of biliary lithiasis, cholangitis, and biliary abscess formation. Rarely, patients can present later in life with complications secondary to poal hypeension. Approximately 33% of affected patients develop biliary lithiasis and 7% develop cholangiocarcinoma. Ref: Schwaz's principle of surgery 9th edition, chapter 31.