[Refractory anemia showing excess of blasts (BAEB) that transformed into acute myelogenous leukemia (AML-M2) with a t (?8;20) chromosomal abnormality].

In April, 1985, a 60-year-old Japanese male was diagnosed as having refractory anemia with an excess of blasts (RAEB). He thus was treated solely with blood transfusions until June, 1986, when a new diagnosis revealed that his illness had been transformed into acute myelogenous leukemia (M2). Chromosome analysis at the initial diagnosis had revealed a normal male karyotype. When the subsequent diagnosis of AML was made, however, a chromosomal abnormality [46, XY, -20, +der (20) t (?8;20) (q22;p13)] was detected. Myelodysplastic syndrome (MDS) in patients evidencing a karyotypic alteration from the initial karyotypic findings progresses in severity that includes overt leukemia, and results in a shorter survival than in patients who show no further karyotypic changes. Therefore, the prognosis of patients with MDS can be predicted more accurately by subsequently reanalyzing their chromosomes after the initial analysis, as well as by examining their peripheral blood/counts, and by monitoring bone marrow cytology.