腹腔鏡下胆囊摘出術時に発見された副肝の1例

A case of accessory liver on the gallbladder wall found during laparoscopic cholecystectomy

◆要旨：副肝は本邦で約60例の報告をみるにすぎない稀な肝の発生異常である．今回，筆者らは腹腔鏡下胆囊摘出術の際に副肝と診断された症例を経験した．患者は39歳，男性．腹部造影CTで胆石を認めるほか，胆囊壁腹側に造影効果の不明瞭な扁平腫瘤を認めた．悪性腫瘍を考慮しつつ手術を施行したところ，胆囊体部腹側に径約2cm大の肝とほぼ同色の結節を認め，胆囊とともに摘出した．病理組織学的診断にて副肝と診断された．副肝にはグリソン鞘が形成されており，CTでは肝と同様に造影されていたと考えられるが，腫瘤が小さいために造影効果が不明瞭であったと考えられた．

　Accessory liver is a rare congenital abnormality, with only 60 cases reported in Japan. We report a case of accessory liver on the gallbladder wall found during laparoscopic cholecystectomy in a 39-year-old man. We found stones in the gallbladder and a nodule on the gallbladder showed irregular staining by enhanced CT. We were not able to deny a malignant tumor. The nodule of 2 cm was observed on th serosal surface of the gallbladder and was colored like the liver. We performed laparoscopic cholecystectomy with the nodule. Pathologically, the nodule showed normal liver tissue that possessed hepatic lobules, it was diagnosed as accessory liver. It was considered that althongh the accessory liver showed staining that was the same density as the liver, it was to small to show a regular staining effect in enhanced body CT.