Objective: To investigate the laboratorial and clinical characteristics of t(8;21) AML, and to compare the differences between patients with additional chromosomal abnormalities and those without additional aberrations.
Methods: Seventy-two cases of t(8;21) AML were analyzed retrospectively, including features of morphology, initial blood cells, cytogenetic G-banding karyotype, immunophenotype, AML1/ETO fusion gene and clinical outcome. In order to compare the characteristics of patients with additional chromosomal abnormalities with those with t(8;21) alone, these patients were divided into two groups according to their karyotype as follows: Group A included patients with t(8;21) alone; Group B included patients with additional aberrations.
Results: According to FAB classification, there were 65 cases of M2, 5 cases of M4 and 2 of M5. Cytogenetically, 45 cases (62.5%) were accompanied by additional chromosomal abnormalities. The main additional aberrations included -Y, +4, del(9q). There were no obvious differences between these two groups in their features of age distribution, bone marrow blast cells, Auer rods, eosinophilia, immunophenotype, as well as central nervous system leukemia occurrence and complete remission rate of induction, but a male prevalence and a lower initial WBC were observed in Group B. With a follow up of 1-96 months, the median survival time was much longer in group A (65 months) compared with group B (12 months), but there was no difference between the four main subgroups of group B. The estimated 3-year survival was (63.9+/-11.2)% in group A compared with (20.9+/-9.2)% in group B.
Conclusion: Additional chromosomal abnormality is an adverse factor for prognosis of t(8;21) AML. The median survival time of patients with additional aberrations was much shorter than that of those without.