title: Differential diagnosis for intrahepatic biliary cystadenoma and hepatic simple cyst: significance of cystic fluid analysis and radiologic findings.
abstract: OBJECTIVE
  This study evaluated the significance of cystic fluid analysis and radiologic findings in the differential diagnosis of biliary cystadenomas (BCA) and hepatic simple cysts (HSCs).
  
  
  BACKGROUND
  BCA are premalignant lesions. The treatment of choice is surgical excision. It is important to differentiate BCA from HSCs because they have different clinical significances and treatment plans. However, it is difficult to preoperatively differentiate a BCA from a HSC.
  
  
  METHODS
  This retrospective study was done with 31 patients suffering from pathologically diagnosed BCA or HSC. All patients underwent surgery between May 1995 and June 2008 at a single institution and had cystic fluid analysis preoperatively or intraoperatively.
  
  
  RESULTS
  We discovered no statistically significant differences in cystic fluid carbohydrate antigen 19-9 (CA 19-9) levels or carcinoembryonic antigen levels when comparing BCA (n=17) and HSCs (n=14). BCA were significantly more frequently associated with female sex (17/17 vs. 10/14, P=0.032), presence of a septum (16/17 vs.5/14, P=0.001), and septal thickening (8/17 vs. 1/14, P=0.021). All 3 cases with calcifications belonged to the BCA group, but sample size was too small to demonstrate statistical significance. There were no statistically significant differences in other clinical and radiologic findings including age, presence of symptoms, serum tumor markers, serum chemistry, size, location, lobulation, septal enhancement, wall enhancement, wall thickening, mural nodule, or biliary dilatation.
  
  
  CONCLUSIONS
  Cystic fluid carbohydrate antigen 19-9 levels and carcinoembryonic antigen levels were not useful for differential diagnosis of BCA vs. HSC. BCA were more common than HSCs in females, patients with a septum, and patients with septal thickening.
authors.affiliation: Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hyo Kyung
authors.initials: HK
authors.lastname: Choi
authors.forename: Jong Kyun
authors.initials: JK
authors.lastname: Lee
authors.forename: Kwang Hyuck
authors.initials: KH
authors.lastname: Lee
authors.forename: Kyu Taek
authors.initials: KT
authors.lastname: Lee
authors.forename: Jong Chul
authors.initials: JC
authors.lastname: Rhee
authors.forename: Kap Hyun
authors.initials: KH
authors.lastname: Kim
authors.forename: Kee-Taek
authors.initials: KT
authors.lastname: Jang
authors.forename: Seong Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Yulri
authors.initials: Y
authors.lastname: Park
mesh_terms: D000368:Aged; D001661:Biliary Tract Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D018395:CA-19-9 Antigen / Q000032:analysis; D002272:Carcinoembryonic Antigen / Q000032:analysis; D020420:Cyst Fluid / Q000737:chemistry; D003537:Cystadenoma / Q000175:diagnosis* / Q000000981:diagnostic imaging; D003560:Cysts / Q000175:diagnosis* / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008107:Liver Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography
chemical_list: D018395:CA-19-9 Antigen; D002272:Carcinoembryonic Antigen