This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
True about Biliary cystic adenocarcinoma 
Select and explain. 
A. CT scan is used for diagnosis, B. CA 19-9 is elevated, C. intrahepatic location, D. Extrahepatic location
A: CT scan is used for diagnosis
Answer: A: CT scan is used for diagnosis 
Explanation: Hepatic cystadenocarcinoma arising from pre-existing cystadenoma with mesenchymal stroma, which occurs only in young females, carries good prognosis resection is the treatment it carries a good prognosis. MRI is diagnostic. 
US/CT scan is also helpful. ERCP is done to identify communication with the biliary system usually to proximal left hepatic duct.