深達度smの胃MALTリンパ腫の1例

Primary Gastric Lymphoma of Mucosa-Associated Lymphoid Tissue Type, Report of a Case

要旨　患者は57歳，女性．人間ドックの上部消化管造影検査および内視鏡検査で，胃角部前壁に陥凹性病変を指摘され，精査・加療のため当科へ入院となった．上部消化管造影検査では，胃角部前壁に粘膜集中を伴う比較的境界明瞭な浅い陥凹を認め，その辺縁に明らかな不整像は認めなかった．陥凹に連続して粗大顆粒状変化を呈する局面を認めたが，その範囲は判然としなかった．上部消化管内視鏡検査でも同様の所見であり，表層型胃悪性リンパ腫と診断した．生検で悪性リンパ腫と確診され，胃全摘術が施行された．病理組織学的に，深達度smのmucosa-associated lymphoid tissue（MALT）リンパ腫であった．脈管侵襲，リンパ節転移は認めなかった．

　During a medical checkup examination, a Ⅱc-like depressed lesion of the stomach was discovered in a 57-year-old woman. She was admitted to our hospital for more precise examination. Radiographic and endoscopic study revealed a shallow depressed lesion and mucosa with granular pattern. The gastric area remained on the surface of the depression. The margin of depression was partially unclear and the margin of the granular mucosa was also unclear. From these findings, we diagnosed this case as gastric lymphoma and the result of the biopsy diagnosis was malignant lymphoma. Total gastrectomy was performed. Histopathologically, centrocyte-like cells had infiltrated the interfollicular area. A lymphoepithelial lesion was recognized in the deep of mucosa. Pathological diagnosis was primary gastric lymphoma of mucosa-associated lymphoid tissue type. The depth of invasion into the gastric wall was mainly limited to the mucosa, but the tumor partially invaded to the submucosa. Lymphatic invasion, blood vessel invasion, and lymph node metastasis were negative.