Cystic Neoplasms of the Liver: Biliary Cystadenoma and Cystadenocarcinoma

Cystic diseases of the liver occur in about 5-10% of the population.(1) While simple cysts are most common, biliary cystic tumors (BCT), namely biliary cystadenoma (BCA) and cystadenocarcinoma (BCAC) can arise in a subset of patients. Hueter first reported BCA in 1887 and Keen reported the first BCA resection five years later.(2, 3) Since that time, there has been a relative paucity of data published on the surgical management of BCT. Due to the rarity of BCT, many clinicians may be unfamiliar with the diagnostic features, therapeutic management, and natural history of these liver neoplasms. We herein provide an evidence-based review of BCT with particular emphasis on early recognition and approach to management. A search of available electronic databases including MEDLINE/Pubmed using the terms “biliary cystadenoma”, “biliary cystadenocarcinoma”, and “non parasitic hepatic cysts” was conducted. Additionally, we searched the MeSH database under the heading “Liver Neoplasm” in combination with the above referenced terms and Boolean operator AND or OR. Criteria for inclusion included English language articles using human subjects (Figure 1). Figure 1 A PRISMA diagram defining the method of inclusion and exclusion for studies utilized in the review. Incidence and Epidemiology Biliary cystic tumors (BCT), such as biliary cystadenoma (BCA) and cystadenocarcinoma (BCAC), comprise less than 5% of all liver cysts.(4) While BCA occurs predominantly in females (90%), BCAC is more evenly distributed between men and women.(2, 5-10) The mean age at presentation of BCA is 45 years versus BCAC which typically presents a decade later.(7-11) While 10% of reported BCT originate in the extrahepatic biliary tree, the overwhelming majority arises from the intrahepatic biliary system.(12-15) BCT are typically slow growing lesions with a reported size that can range in diameter from 1.5 to 35 cm.(6, 10, 16, 17) Based on the mesenchymal stroma and the epithelium resembling endodermal (primitive hepatobiliary) cells that can be seen in BCT, Wheeler and Edmondson hypothesized that BCA arise from ectopic rests of embryonic bile ducts.(18, 19) However, 50% of BCTs contain endocrine cells suggesting that they may originate from intrahepatic peribiliary glands.(10, 20) BCAC is thought to originate either de novo from formed biliary ducts induced by ischemia and carcinogens or from malignant transformation of a preexisting BCA.(18, 19, 21) The latter theory is supported by the multiple reports of benign epithelium within BCAC specimens.(8, 10, 18, 21, 22) For example, Devaney et al. (10) reported malignant transformation in 6 of the 18 BCAC in their series as well as cytological atypia/dysplasia in a number of BCA.