粘膜下腫瘍様の形態を呈した早期胃癌（粘膜内癌）の1例

Early Gastric Cancer（M）, Showing SMT Like Appearance, Report of a Case

要旨　患者は70歳代，男性．他院のスクリーニング上部内視鏡検査にて異常の指摘を受け，当科へ紹介され，受診となった．上部消化管X線造影および内視鏡検査にて，胃体上部後壁大彎に中心陥凹を伴う粘膜下腫瘍様病変が認められ，2度目の生検にて乳頭腺癌と診断された．超音波内視鏡検査でSM浸潤癌と診断し，噴門側胃切除術を施行した．切除標本で隆起病変の大きさは15×15mm，中心部には明瞭な陥凹を認めた．最終的な病理組織学的所見は，pap，M，ly0，v0，n0であった．粘膜筋板が偽憩室様に粘膜下層へ内反・菲薄化した形態を呈しながら，腫瘍を取り囲むように確認された．その発育進展形式は示唆に富む症例であると考えられたので，ここに報告する．

　We report an intriguing case of early gastric intramucosal carcinoma presenting a submucosal tumor-like feature. A man in his seventies was referred to our hospital for further examination. X-ray and endoscopic examinations revealed a submucosal tumor with central depression at the posterior wall in greater curvature of the upper portion of the stomach. Two biopsies were made and the second one revealed papillary adenocarcinoma. Endoscopic ultrasonography demonstrated hypo-echoic lesion infiltrating into the third layer of the gastric wall. Thus we diagnosed sm-invasive carcinoma and proximal gastrectomy was performed. The resected specimen showed an elevated lesion measuring 15×15mm with a distinct depression in the center. The final pathological diagnosis was 0-IIc, pap, m, ly0, v0, n0, stage Ia. The thinning muscular layer of mucosa was detected surround the tumor, just as inverting submucosal layer like a pseudodiverticulum. The way of development was very intriguing.