粘膜下異所性胃腺より発生したと考えた粘膜下腫瘍様形態を呈した早期胃癌の1例

Early Carcinoma of the Stomach Resembling Submucosal Tumor, Report of a Case

要旨　患者は66歳，男性．空腹時心窩部痛を主訴に近医受診．胃内視鏡検査で胃粘膜下腫瘍を認めたため，当院に紹介された．胃体下部後壁に，中心にびらんを伴う粘膜下腫瘍様病変を認め，生検で中分化型腺癌と診断された．胃癌の診断で2000年2月23日，幽門側胃切除術＋D2郭清を施行した．摘出標本では腫瘍は30×20mmで，病理組織学的所見はtub2，sm，ly0，v0，n0であった．癌は粘膜面にわずかに露出するのみで主座は粘膜下に存在し，さらに腫瘤に一部非癌粘膜が存在することから粘膜下の異所性胃腺を発生母地として発癌し，膨張性に発育した胃癌と考えられた．

　A 66-year-old man complaining of epigastralgia was referred to our hospital. Gastrointestinal fiberscopy findings revealed, in the body of the stomach, a submucosal tumor-like lesion with central concavity. Biopsy of the tumor revealed moderately differentiated adenocarcinoma. Distal gastrectomy was performed under a diagnosis of gastric cancer. Histologically, the tumor was diagnosed as moderately differentiated adenocarcinoma (sm, 1y0, v0, n0), invading the submucosal layer and extending to the submucosal layer with heterotopic gastric mucosa. To sum up, this tumor was composed of cancer and submucosal heterotopic gastric glands and had expanded in the submucosal layer.