鏡視下に切除した胆囊管原発神経鞘腫の1例

A rare case of schwannoma of the cystic duct successfully treated by laparoscopic cholecystectomy

◆要旨：症例は69歳，女性．急性胆管炎を発症し，腹部CTで肝十二指腸間膜右背側から総胆管に接する最大径30mm大の腫瘤を認めた．超音波内視鏡下穿刺吸引細胞診の結果，神経鞘腫と診断された．腹腔鏡下に肝十二指腸間膜を検索すると，腫瘍は総胆管に接していたが，術中胆管造影で胆囊管発生と診断され，腹腔鏡下胆囊摘出術で切除し得た．病理組織学的検討により胆囊管原発神経鞘腫と確定診断された．胆囊管原発神経鞘腫はきわめて稀であり，術前診断が困難なことから悪性腫瘍に準じた手術が実施されることもある．今回われわれは，術前組織診断に基づき低侵襲な鏡視下手術で切除し得た症例を経験したため，文献的考察を加えて報告する．

　A 69-year-old woman was admitted to the hospital with a complaint of abdominal pain. Abdominal enhanced computed tomography showed a well-defined tumor measuring 30 mm in diameter with contrast effect in the hepatic hilum. Endoscopic ultrasound showed a compression of the common bile duct due to the tumor. Based on the histological findings of a specimen obtained by endoscopic ultrasound-fine needle aspiration, the tumor was diagnosed as an schwannoma. Although the origin of the tumor was not determined by preoperative examination, a laparoscopic approach was applied for this case. Intraoperative examination of the hepatic hilum revealed that the tumor was localized close to the right side of the common bile duct. Intraoperative cholangiography showed a filling defect in the cystic duct and common bile duct with a crab claw-like appearance.

　With careful manipulation, the tumor was successfully removed without damaging the common bile duct by laparoscopic cholecystectomy.

　Histopathological examination showed spindle-shaped cells with nuclear palisading in the tumor, which were positive for S-100 protein and negative for CD34, c-kit,αSMA, and desmin. The tumor was in contact with the fibromuscular layer of the cystic duct, suggesting that the tumor was derived from the cystic duct.

We report a rare case of schwannoma of cystic duct successfully resected by laparoscopic cholecystectomy with a review of literature.