虫垂開口部に粘膜下腫瘍様形態を呈した虫垂結石の1例

Appendiceal Calculus with Submucosal Tumor-like Appearance at the Appendiceal Orifice, Report of a Case

要旨　患者は57歳，男性．自己免疫性膵炎精査中に腹部骨盤部CTで回盲部に腫瘤状の石灰化病変を指摘された．注腸X線検査では盲腸に大きさ2cm程度の表面平滑な隆起性病変が描出され，大腸内視鏡検査では糞便物が貯留した陥凹面を伴う粘膜下腫瘍様隆起を認めた．超音波内視鏡検査では同部位に強い音響陰影を認め，虫垂結石と診断した．腹腔鏡下盲腸切除術が施行され，手術標本では虫垂根部は盲腸内腔側に反転し，内部に3cm大の結石を認めた．粘膜下腫瘍様形態を呈する虫垂結石は非常にまれであるが，盲腸の隆起性病変の鑑別診断として考慮する必要があると考えられた．

　A 57-year-old man visited our hospital for further examination concerning autoimmune pancreatitis, and a calcified mass lesion was detected in the ileo-cecal region on abdominal CT scan. Barium enema showed an elevated lesion with smooth surface and about 2cm in size in the cecum. Colonoscopic study revealed a submucosal tumor-like lesion with a depressed area filled with fecal crusters. Endoscopic ultrasonography displayed a strong acoustic shadow at the lesion, so we diagnosed it as an appendiceal calculus. Laparoscopy-assisted cecectomy was perfomed, and revealed a stone about 3cm in diameter in the lumen of the appendix rolling about to the cecum. Appendiceal calculus with submucosal tumor-like appearance is very rare, but we must take it into consideration in differentiation from elevated lesions of the cecum.