MDS with complex chromosomal aberrations (CCA) are characterized by short survival and a high rate of transformation to AML. A comprehensive genome-wide analysis of bone-marrow cells of 157 adults with newly diagnosed MDS and CCA revealed a large spectrum of nonrandom genomic changes related to the advanced stages of MDS.
Chromosome shattering, probably resulting from chromothripsis, was found in 47% of patients. Deleted chromosome 5 was unstable and often involved in different types of cryptic unbalanced rearrangements.
No true monosomy 5 was observed. Patients with CCA involving deleted chromosome 5 had an extremely poor prognosis (median overall survival, 2 months).