[Atypical chronic myeloproliferative disorder with translocation (12;13) (p13;q12) and tumor formation].

A 49 year-old man was admitted to our hospital in May 1989, with a cervical tumor and leukocytosis. He had been pointed out leukocytosis for last two years. Peripheral blood examinations demonstrated an increase of leukocytes (39,500/microliters) with low neutrophil alkaline phosphatase, eosinophilia and immature cells. Examination of bone marrow revealed normoplasia with 5.6% eosinophils, 1.4% myeloblasts, 2.6% promyelocytes and 250/microliters megakaryocytes. Cytogenetic analysis disclosed 46, XY, t (12;13) (p13;q12). Southern blot analysis showed no BCR rearrangement. The tumor cells had infiltrated the lymph nodes. Pathological finding agreed with the specimen of the lymph node as in the clot section of bone marrow. He was diagnosed as having a chronic myeloproliferative disorder with tumor formation and was treated with anti-leukemia drugs, including BH-AC, THP, VDS, MTX, VP-16, BUS, 6MP and uvenimex. He showed hematological remission, temporary, but he did not reach cytogenetical remission and died in April 1990. Further study in a large series is necessary to define whether the abnormality of the chromosome with t(12;13) (p13;q12) is characteristic in cases with tumor formation.