Additional karyotype abnormalities in t(8;21) associated acute myeloblastic leukemia (AML).

Correlations between the presence of additional (secondary) karyotype changes and clinicohematological features of AML associated with a-specific chromosomal trans location t(8;2 1). Additional abnormalities were detected in 38 of 42 patients, (90.5%). Loss of one sex chromosome and marker 9q- was the most frequent abnormality (38.5 and. 33.5%, respectively). Few cases had other various chromosome abnormalities. Two subgroups of patients were compared on the basins of the literature data on favourable or unfavourable response to the therapy. Group 1 included 4 patients with t(8;21:) alone and 16 patients with loss of one sex chromosome. The rest 22 patients entered group 2. The age of the patients, size of the spleen and liver, WBC, BM and PB blastosis and immunophenotypical markers were compared. The absolute blast count in PB was higher in group 2 (p < 0.05). It is suggested that certain additional chromosome abnormalities and a higher PB blast count are associated With the disease. progression.