赤芽球ろうを伴ったＣＤ５陽性Ｂ細胞リンパ腫 症例報告と文献的考察

Abstract

A 41-year-old woman was admitted because of severe anemia (Hb 6.1g/dl). She had a systemic lymphadenopathy but no hepatosplenomegaly. The anemia was normocytic and was accompanied by reticulocytopenia (0‰) and the platelet count was normal, and many abnormal lymphoid cells were seen in the peripheral blood. The bone marrow aspirate revealed massive invasion of abnormal lymphoid cells and extreme erythroid hypoplasia (erythroblasts 1.5%). These abnormal cells were positive for Sm IgG, Sm IgD, Smλ, CD19, CD20 and CD5, but negative for Sm IgM, Sm IgA, Smκ and CD10. IgG-λ M-protein was detected in the serum. A pathologic diagnosis of “Malignant lymphoma, diffuse, medium sized cell type” was made by the lymph node biopsy. After three courses of CHOP-therapy, the lymph nodes decreased and the lymphoma cells disappeared from the blood, but her anemia with reticulocytopenia persisted. At this time the counts of granulocytes and megakaryocytes of the bone marrow were normal, but erythroid hypoplasia still continued (erythroblasts 6.8%). Shortly thereafter, however, a marked reticulocytosis occurred suddenly and then the anemia improved rapidly. Eight months later the lymphoma relapsed and many lymphoma cells reappeared in the bone marrow, but pure red cell aplasia (PRCA) did not recur. Although the pathogenesis of PRCA is unknown, this case indicates that not only B-CLL but also CD5-positive B cell lymphoma is accompanied by PRCA.