Biliary cystadenoma –an enigmatic diagnosis still?
*Corresponding author:Amarjothi J M V ,500, Tower block II, Rajiv Gandhi Government General Hospital, Chennai, Tamilnadu, India; E-mail: email@example.com
Biliary cystadenoma are rare cystic neoplasms (<5%) of the liver . They arise from the biliary epithelium and are most commonlymultiloculated, cystic lesions lined by cuboidal or columnar epithelium with or without ovarian stroma. and are seen in the intrahepatic location (85%).
The exact etiology is incompletely understood. As the lesions are more common among middle aged female patients, a hormonal etiology involving estrogen is plausible [3,4]. Clinical features may be variable and may range from asymptomatic to abdominal pain, distension or rarely jaundice. The differential diagnosis for intrahepatic biliary cystadenomas includes a myriad of liver cysts like simple cysts, hydatid cysts, atypical liver abscess and degeneration of malignancy .
Radiological investigations are not specific to diagnose biliary cystadenomas or cystadenocarcinomas due to lack of specific features and are commonly misdiagnosed as liver cysts (simple or hydatid). However, features like internal septations, internal echoes, wall enhancement, hypovascular wall, thickened wall, mural nodules andcalcifications mayoccur . Thickened wall, mural nodules and calcifications may also be seen in case of cystadenocarcinomas and are not definite markers of malignancy. The incidence of malignant transformation is around 30%  and there are no reliable features to diagnose biliary cystadenocarcinomas from biliary cystadenomas.
Ultrasound is highly sensitive to diagnose the fine septae but is highly dependent on accessible location and operator expertise . CT done can detect calcifications and the portal venous phase is needed to diagnose the septate accurately. MRI in the T2  is best to diagnose the fine septae and intracystic bleeding. Cysts with a high mucin content can be diagnosed on T1. DWI (Diffusion weighted imaging) is helpful to diagnose malignant transformation.
In a retrospective study of 20 cases of preoperative diagnosis of biliary cystadenomas, [ 1] 6 were histologically proven after surgery with a diagnostic accuracy of only 30%. 50% of the preoperatively misdiagnosed biliary cystadenoma(n=5) were actually livercysts (simple-3, hemorragic-1, infected -1).Two large cysts in the study which were thought to be simple cysts were persistently recurrent to various modalities like alcohol sclerotherapy and laparoscopic fenestration and ultimately required complete removal of the cyst whichwere histologically positive for biliary cystadenoma reflecting on the need for complete cyst wall excision to adequately treatmisdiagnosed biliary cystadenoma. Another study by Thomas et al  gave a very high diagnostic accuracy of 95% of biliary cystadenomas but the exact diagnostic features employed are unknown.s.CA19-9 levels may be elevated  but is not specific. FNAC and frozen section are not accurate due to high false negative rates butmay reveal clear fluid with high ca 19-9 levels and mildly elevated CEA levels . The raise in fluid CA 19-9 levels is not diagnostic of biliary cystadenoma as it is seen with malignant transformation also . It is not known whether the levels of CA19-9 correlate with malignancy and no cut off levels have been describedso far.Histology of the excised specimen is diagnostic for biliary cystadenoma with some showing ovarian stroma. It is to be noted that those associated with ovarian stroma are associated with better prognosis though having higher predisposition for malignant transformation .
Treatment for biliary cystadenoma stresses on complete excision of cyst wall to prevent recurrence . Enucleation of the cyst wall may be preferable to liver resection as it is associated with lower morbidity . For lesions not amenable to complete excision, partial excision with adequate treatment of the remnant cyst wall must be carried out earnestly to prevent recurrence . Liver transplantation may be last and only resort for large unresectable biliary cystadenomas [13,14].
The prognosis for completely excised biliary cystadenomas is excellent emphasizing that nothing but complete removal of the cyst wall is necessary to prevent recurrence and malignant transformation.
It is to be noted that a high index of diagnostic suspicion for biliary cystadenoma must be entertained in all preoperative diagnosis of simple liver cysts especially those with high fluid ca 19-9 levels. Treatment of such cysts should be tailored such that those which are undergoing surgical excision (enucleation or liver resection) should undergo complete excision of their wall in order to prevent recurrence.
Conflict of interest-Nil
- Teoh AY1, Ng SS, Lee KF, Lai PB. Biliary cystadenoma and other complicated cystic lesions of the liver: diagnostic and therapeutic challenges. World J Surg, 2006; 30: 1560–1566.
- Edmondson HA. Tumours of the liver and intrahepatic bile ducts. In: Atlas of tumour pathology, fasc. 25, ﬁrst series. Washington, DC, Armed forces Institute of Pathology, 1958
- Lee CW, Tsai HI, Lin YS, Wu TH, Yu MC, Chen MF. Intrahepatic biliary mucinous cystic neoplasms: clinicoradiological characteristics and surgical results. BMC Gastroenterology, 2015; 15: 67-72. [CrossRef]
- Kim HH, Hur YH, Koh YS, Cho CK, Kim JW. Intrahepatic biliary cystadenoma: Is there really an almost exclusively female predominance? World J Gastroenterology 2011; 17: 3073-84.
- Devaney K, Goodman ZD, Ishak KG. Hepatobiliary cystadenoma and cystadenocarcinoma: a light microscopic and immunohistochemical study of 70 patients. Am J SurgPathol1994;18:1078–1091
- Treska et al.Intrahepatic biliary cystadenoma-diagnostic and treatment options. Turk J Gastroenterol 2016; 27: 252-6
- Thomas KT, Welch D, Trueblood A, et al. Effective treatment of biliary cystadenoma. Ann Surg2005; 241:769–775.
- Lee JH, Chen DR, Pang SC, et al. Mucinous biliary cystadenoma with mesenchymal stroma: expressions of CA 19-9 and carcinoembryonic antigen in serum and cystic ﬂuid. J Gastroenterol 1996; 31:732–736.
- Koffron A, Rao S, Ferrario M, et al. Intrahepatic biliary cystadenoma: role of cyst ﬂuid analysis and surgical management in the laparoscopic era. Surgery 2004;136:926– 936.
- Tsepelaki A. Biliary Cystadenoma of the Liver: Case report and systematic review of the literature. ANNALS OF GASTROENTEROLOGY 2009, 22(4):278-283
- Lewis WD, Jenkins RL, Rossi RL, et al. Surgical treatment of biliary cystadenoma: a report of 15 cases. Arch Surg1988;123:563–568.
- W. Pinson, J. L. Munson, R. L. Rossi, and J. W. Braasch, “Enucleation of intrahepatic biliary cystadenomas,” Surgery Gynecology and Obstetrics, vol. 168, no. 6, pp. 535–537, 1989.
- Grubor NM, Colovic RB, Atkinson HD, Micev MT. Giant biliary mucinous cystadenoma of the liver. Ann Hepatol 2013; 12: 979-83.
- Nakawa M, Matsuda M, Masaji H, Watanabe G. Successful preoperative diagnosis of biliary cystadenoma with mesenchymal stroma and its characteristic imaging features: Report of two cases. Turk J Gastroenterol 2011; 22: 631-5.