膵原発と思われた神経鞘腫の1例

Neurilemmoma of the pancreas: A case report and literature review

　縦隔や胃をはじめとする消化管に発生する神経鞘腫の報告は散見されるが，膵原発の神経鞘腫の報告例はきわめて稀である¹⁾．われわれは最近，病理組織学的検査によって膵原発と思われる巨大な神経鞘腫と判明した症例を経験したので，若干の文献的考察を加えて報告する．

症例

　患　者：60歳　男性　酒類販売業

　主　訴：左季肋部の圧迫感と腫瘤触知

　家族歴：特記すべきことなし

　既往歴：約10年前に左季肋部を打撲したことがある以外に著患を知らず．

　現病歴：1969年来，左季肋部の圧迫感を感じていた．1974年2月7日，食後約5分間にわたって左季肋部に激痛を覚え，同部に児頭大の腫瘤を触知した．その後圧迫感は漸増してきたので，1974年3月19日精査のため当所へ入院した．

　A 60 years old male had a history of a lump and sensation of pressure at the left hypogastric region for about a year. A child-head-sized tumor, palpable at the left hypogastric region, was diagnosed as pancreatic cyst by ultrasonic examination. Laparotomy showed a tumor about 20 cm in diameter in the bursa omentalis, attached to the anterior surface of the pancreas, between body and tail. Neither metastasis nor invasion was found. The tumor was removed en bloc, along with stomach, spleen, left adrenal gland and pancreas distal to the body. He has been healthy for three years after the surgical operation. The resected tumor 24×17×12 cm in size with foci of hemorrhage, cystic spaces and necrotic aseas, was completely encapsulated by a thin fibrous tissue. Histological study demonstrated that the tumor was a benign neurilemmoma consisting of Antoni A and B types. The site of origin was presumably from the peripheral nerve tissue in the pancreas capsule or in the pancreatic stroma.

　A nonepithelial tumor of the pancreas is extremely rare, and only a single case of neurilemmoma in the pancreas has been reported in the Japanese literature. By the histopathological study, neurilemmoma should be differentiated from leiomyoma, fibroma, neurofibroma, and their malignant types. Complete extirpation by surgery is necessary for the treatment of this tumor.