Biliary microhamartoma

Fig. 32.18 von Meyenburg complex biliary microhamartoma with ectatic bile ducts in an enlarged fibrous portal stroma (HE)... 

Benign biliary microhamartomas (= Meyenburg s complex) were described by H. von Meyenburg in 1918. They consist of small cysts developing from dilatations of the small (interlobular) bile ducts and are surrounded by fibrous stroma. The cysts are remnants of ductal plate malformations. Occasionally, typical ductal plates can also be detected. The hamartomas can reach a diameter of up to 0.5 (-1.0) cm. (s. fig. 32.18) Macroscopically,... 

Burns, C.D., Kuhns, J.G., Wieman, T.J. Cholangiocarcinoma in association with multiple biliary microhamartomas. Arch. Pathol. Lab. Med. 1990 114 1287-1289... 

These hepatic cysts are thought to arise from dilatation of biliary microhamartomas (BMH). They demonstrate a cuboidal epithelial lining with the same histological appearance as that of the biliary epithelium, and may contain fluid. These lesions are generally smaller than 10 cm, surrounded by fibrotic tissue and localized close to the portal tracts (Suchy 2003). 

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