[Chromosomal abnormality of trisomy 4 in a patient with acute nonlymphocytic leukemia (FAB: M2)].

We report a patient with acute nonlymphocytic leukemia (FAB classification: M 2) with trisomy 4, which is the first case in our country. A 42-year-old man was admitted to our hospital because of fever and general fatigue in May, 1988. His WBC count was 8,100/microliters with 90% of leukemic cells and bone marrow smear showed 76.1% leukemic cells. The chromosomal analysis of marrow cells by G-banding revealed 47, XY, +4. In spite of administration of chemotherapy complete remission was not obtained, and he died of septic shock and severe liver damage 4 months after making the diagnosis. Chromosomal abnormality of trisomy 4 has been reported to be associated with predominantly either M 4 or M 2, and to be less than 0.1% of incidence in ANLL, according to the Second MIC Cooperative Study Group. It is suggested that trisomy 4 may be caused by exposure to some environmental factors such as toxic substances, since this chromosomal abnormality has been reported in the last 10 to 20 years.