胃原発Burkitt様リンパ腫の1例

Burkitt-like Lymphoma of the Stomach, Report of a Case

要旨　患者は69歳，男性．食思不振を主訴に当科受診．上部消化管X線および内視鏡検査で，その約7か月前には異常を指摘できなかった胃前庭部に潰瘍を伴う粘膜下腫瘍様隆起を認め，胃生検で悪性リンパ腫と診断．骨髄穿刺で骨髄への浸潤を認めた．経過中に腫瘤は増大発育し，吐血を来したため主に止血を目的として胃部分切除術を施行．腫瘍は全層性，びまん性に増殖した中型から大型の異型リンパ球で，間に貧食細胞が散在するstarry sky像を呈し，免疫組織化学検査で腫瘍細胞はCD20，SmIgM陽性，またc-myc遺伝子に対する抗体が陽性で，Burkitt様リンパ腫と最終診断した．術後化学療法を施行したが，診断4か月後には中枢神経症状が出現し，6か月後に肝不全，呼吸不全のため死亡した．

　A 69-year-old man was admitted with a complaint of anorexia. Radiographic and endoscopic studies revealed a submucosal tumor-like lesion with an ill-defined ulcer in the center in the antrum, which was not detected seven months before admission. The biopsy specimens from this lesion showed a feature of malignant lymphoma. Bone marrow aspiration examination revealed involvement of the bone-marrow. Because of the enlargement of the tumor and massive hematemesis, we performed distal partial gastrectomy. Histological finding of the tumor showed a “starry sky” pattern of the macrophages interspreading among atypical large lymphoid cells and many tumor cells which were positive for cytoplastic staining by anti-c-myc antibody reaction using ABC alkaline phospatase method. We performed chemotherapy after operation, however, he developed central nervous symptoms four months after admission, and died two months later because of hepatic and respiratory failure. We diagnosed the tumor of this patient as Burkitt-like lymphoma based on clinical aspects and histological findings.