2ヵ月間で著しい胃変形のみられた胃形質細胞腫の1例

Gastric Plasmacytoma and Remarkable Contraction of the Stomach within Two Months

　髄外性の形質細胞腫は上気道，口腔に多く胃原発のものは極めてまれとされている¹⁾．本邦においては最近報告が増加し15例の報告がある^2)～15)．

　今回，2年間の経過中，手術前2カ月足らずの間に突然胃壁の硬化と収縮を来した良性びまん性胃形質細胞腫を経験したので，その形態の変化および形質細胞の増殖の特徴について組織学的に検討を加えて報告する．

　A58-year-old woman was followed-up for two years because of persistent abdominal pain. Her stomach was found to be rigid and shrunken within two-month period. She was operated on because of suspicion of scirrhous cancer. The resected specimen revealed that the gastric wall was edematous and hypertrophic, there were peripheral radiating rugae with an oval concaved lesion of 5×3cm large, which had erosionlike hypermic area without mucosal defect and the hyperemia also discretery localized in the antrum and the body. Histologically plasmacytic infiltration spread diffusely all over the gastric wall, especially the mucosal layer and some perivascular region. The plasmacytes were matured cell without malignant change. Among them there were also some neutrophils, eosinophils and lymphocytes. This varied proliferation might be a reactive one. As for the erosion-like red mucosa, the glandular structure was almost replaced by plasmacytic infiltration with some sharply demarcated intactsegments. The arrangement of muscularis mucosae was disturbed where the glandular structure was destroyed. The findings of reactive plasmacytosis, increased perivascular plasma cells and segmental destruction of glandular structure may be of immunological origin. The contraction of the gastric wall is due to submucosal fibrosis after long-term edema as that of scirrhous cancer.

　Total protein and electrophoresis were within normal limits and no Bence Jones' protein was detected. The levels of serum IgA was 610mg/dl and IgM was 290mg/dl as determined after the operation. These increase levels of igA and IgM were considerd to be a reactive one.