南予医学雑誌　第18巻

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南予医誌　Vol.18　No. １　2017－78－dose methotrexate， high-dose cytarabine and intrathecal chemotherapy and course２（C２）with dasatinib for 28 days and intrathecal chemotherapy．In May 2016， after two cycles of C１， the major bcr-abl mRNA level in the peripheral blood was 0.19％．However， on the 26th day of ２ cycles of C２， the patient developed lower gastrointestinal bleeding that required red blood cell transfusion and a four-week inter-ruption of the chemotherapy．Although the bleeding was almost relieved， bone mar-row aspiration in July 2016 revealed cells morphologically similar to those at the time of initial diagnosis， accounting for 69.1％ of nucleated cells， and thus suggestive of relapse．FISH analysis revealed that BCR-ABL-positive cells accounted for 76.5％ of cells in the bone marrow．Flow cytometry， chromosomal analysis of the bone marrow， and a bone marrow clot section yielded results similar to those at the time of initial diagnosis．The patient therefore received hyper-CVAD chemotherapy consisting of cyclophosphamide， vincristine， doxorubi-cin， and dexamethasone．Dasatinib was withdrawn， but the patient did not achieve even hematological CR．In August 2016， at the request of the patient， cytotoxic chemotherapy was discontinued， and only dasatinib（140㎎/day）and prednisolone（10㎎/day）were administered thereafter．Af-ter one month of dasatinib and prednisolone administration， the dosage of dasatinib was reduced to 100㎎/day because of throm-bocytopenia．The patient obtained a second （Fig.２）Myeloperoxidase（MPO）staining．About ４％ of these blastoid cells show myeloperoxidase staining（×1,000）．