粘膜下腫瘍様形態を呈した胃高分化型腺癌の1例

Well Differentiated Adenocarcinoma of the Stomach Mimicking a Submucosal Tumor, Report of a Case

要旨　患者は68歳，男性．主訴はタール便．当院心臓外科に僧帽弁置換術のため入院．術後12日目より貧血の進行，タール便を認めたため上部消化管内視鏡施行した．出血源は胃体中部小彎の良性潰瘍であった．その際，前庭部後壁にひだの集中を伴う25mm大の粘膜下腫瘍様病変を認めた．頂部にわずかな不整形陥凹を認め，同部の生検より高分化腺癌と診断し，外科的切除を行った．切除標本にて陥凹面に一致して癌の表面への露出を認めたが，大部分で粘膜表層は非腫瘍性であった．癌細胞は管腔を形成しつつ著明な線維化を伴いながら漿膜下層まで浸潤しており，粘膜下腫瘍様胃癌としてまれな発育様式を示した1例と考えられた．

　The patient was a 68-year-old male. His chief complaint was tarry stool. Upper gastrointestinal series and endoscopy showed a submucosal tumor-like elevated lesion with central depression in the posterior wall of the antrum of the stomach. Most of the lesion was covered with normal gastric mucosa. A biopsy specimen from the central depression revealed a well-differentiated adenocarcinoma, so we diagnosed this lesion as a gastric cancer mimicking a subumucosal tumor. Total gastrectomy was performed. Pathological diagnosis was well-differentiated adenocarcinoma invading the subserosa and accompanied by prominent fibrosis. However, only a small area of the adenocarcinoma was visible at the surface.