Molecular cytogenetic characterization of acute myeloid leukemia and myelodysplastic syndromes with multiple chromosome rearrangements

Background and Objectives. Multiple chromosome rearrangements (MCRs) are fo und in 5-10% of newly diagnosed patients with acute myeloid leukemia (AML) and 15-30% of patients with myelodysplastic syndromes (MDS). However, the i nitial causes of MCRs and the molecular mechanisms involved are largely unr esolved. Nor are the karyotypic patterns well studied, mainly because of th e difficulties of obtaining complete karyotypes by G-banding. In this study , we applied spectral karyotyping (SKY) and comparative genomic hybridizati on (CGH) to investigate further the resulting chromosome imbalances and rea rrangements in AML and MDS bone marrow cells with MCRs. Design and Methods. Bone marrow cells from 12 AML and 10 MDS patients with MCRs were collected at diagnosis and analyzed by G-banding, SKY and CGH. Th e patients' characteristics were also collected to pinpoint potential simil arities and/or differences between the patients. Results. Our results show that some MCRs seen in AML are similar to MCRs se en in MDS. These MCRs often result in chromosome loss of 5q, 7q and 17p and gain of chromosome 8. Interpretation and Conclusions. The characteristics associated With MRCs in clude old age, previous exposure to radio- and/or chemotherapy and a short survival time. Probably, these patents should be distinguished from AML pat ients with primary chromosome rearrangements among other unbalanced chromos ome rearrangements. In our experience, SKY and CGH facilitated this process . (C) 2001, Ferrata Storti Foundation.