Cytogenetic analysis of de novo acute myeloid leukemia with trilineage myelodysplasia in comparison with myelodysplastic syndrome evolving to acute myeloid leukemia.

Characteristics of karyotypes were analyzed in de novo acute myeloid leukemia (AML) with trilineage myelodysplasia (AML/TMDS) at initial diagnosis and compared with myelodysplastic syndrome (MDS) cases that had evolved to AML (MDS/AML). Abnormal karyotypes were seen in 11 of 19 patients with AML/TMDS and 13 of 16 MDS/AML cases. Trisomy 8 was observed in 3 AML/TMDS cases as a sole anomaly and was also present in 3 MDS/AML cases but not as a sole finding. Although MDS/AML frequently displayed monosomies or long-arm deletions of chromosome 5, 7 and 9, only one case exhibited long-arm deletion (of chromosome 7) in AML/TMDS. Two or more chromosome aberrations were found in some cases in both groups. These findings suggest that AML/TMDS had passed through several preleukemic stages at diagnosis, as has been well documented in MDS and MDS/AML. Additionally, clonal evolution may have already occurred in AML/TMDS, as MDS transformed to AML is associated with clonal evolution.