Gastric Leiomyoblastoma Showing Exogastric Pedunculated Development

症例は69歳の女性.肝嚢胞, 脂肪肝の経過観察目的で行った腹部CTで, 胃体上部大彎の胃壁外に4cm大の充実性腫瘍を指摘された.胃内視鏡検査ならびに超音波内視鏡検査にて胃固有筋層と連続する平滑筋腫と診断した.さらに, 入院時の胃内視鏡検査で認められた胃壁圧排所見が, 術直前の再検査で消失していたことから有茎性の腫瘍であると判断し, 手術は腹腔鏡下に胃楔状切除を行った.術後病理組織学的に胃平滑筋芽細胞腫.免疫組織学的には狭義のstromal tumorに該当する腫瘍と診断された.術後2年再発なく生存中である.本腫瘍は約30%が胃壁外性に発育するとされている.術前診断率が低く, 特に有茎性に発育することはまれであり, その術前診断, 術式および悪性度診断の問題点を中心に文献的考察を加えて報告した. A 69-years-old woman was admitted to the hospital because of a exogastric tumor 4cm in diameter with a homogenous internal structure as demonstrated by abdominal CT. Endoscopic ultrasonography revealed a tumor described as a hypoechoic lesion containing a echo-free area with continuation to the 4th layer of the gastric wall. Endoscopic examination on admission showed extraluminal compression at the greater curvature of the upper body of the stomach, but at re-examination this finding was not recognized. Under a diagnosis of gastric leiomyoma showing exogastric pedunculated development, a wedge resection of the stomach including the tumor was performed laparoscopically. Histological diagnosis of the resected tumor was leiomyoblastoma. Gastric leiomyoblastoma showing exogastric pedunculated development is very rare, in refference to the literature. We report this case with some additional discussion on the related literature