Abstract
A 58-year-old man was admitted to our hospital complaining of discomfort in the right hypochondrial region. Under the diagnosis of cholelithiasis, cholecystectomy was performed. During the operation, a small mass (1.7×1.2×0.5cm) attached to the serosal surface of the gallbladder was incidentally found. It was oval, red-brown in color with a smooth surface and elasticity was firm. A short mesentery-like tissue connection with the right lobe of the liver was observed. The gallbladder was swollen and contained three mixed stones.
Microscopically, the small mass proved to be the hepatic tissue showing an almost normal liver architecture of the lobule, enclosed in a thin fibrous capsule, thus diagnosed as an accessory liver. There were no particular pathologic changes except for slightly irregular arrangement of central veins and liver cell cords. The portal area had one or two arteries, a single vein and bile ducts with infiltration of small round cells. The mesentery-like tissue consisted of blood vessels, nerve bundles in addition to fibrous connective and adipose tissues, but no bile ducts. Thus, the accessory diver in this case appeared to be supplied by a branch of the hepatic artery and vein. We could not ascertain further connections of extra-hepatic bile duct with this small mass. The gallbladder showed histological features of chronic cholecystitis.
