16歳少女に発生した胃原発の形質細胞腫の1例

Primary Gastric Plasmacytoma Report of a Case

要旨　患者は16歳女性，主訴は心窩部痛，病悩期間約6か月．入院時理学的ならびに臨床検査所見は糞便潜血反応陽性のほか特記すべき所見は認められなかった．胃X線，内視鏡および生検組織診断では，いずれも悪性リンパ腫と診断，手術された．切除標本肉眼所見は胃角より前庭部にかけて表層型悪性リンパ腫の像を呈した．病理組織検査では主として粘膜層内に，核の偏在，異型を伴う大小不同の形質細胞のびまん性の増殖がみられ，形質細胞腫と診断され，更に免疫組織学的検索によってIgM-λ型免疫グロブリンが同定された．そこで単クローン性免疫グロブリン産生の形質細胞腫と診断された．術前・術後の全身骨，骨髄像，他臓器，器官組織には異常は全く認められなかった．

　A case of primary gastric plasmacytoma is presented. A 16 year-old girl visited our hospital with a complaint of epigastralgia. There was no evidence of abnormality in the laboratory findings, especially in serum globulin and also in bone x-ray examination. Gastroscopic examination detected Ⅱc-like lesion with multiple gastric ulcers and erosions in the antral region. We diagnosed it as malignant lymphoma clinically.

　Macroscopic examination showed the Ⅱc-like lesion, 4×4cm in diameter, with irregular multiple ulcers and erosions in the antrum. From macroscopic appearance, malignant lymphoma (superficial type)was diagnosed. Histologically tumor cells had infiltrated the lamina propria and submucosa. Plasma cells appeared with occasional nuclear atypism. Immunohistologically (using PAP method), tumor cells revealed monoclonality for IgM-λ immunoglobulin.