Inverted duplication dup(1)(q32q21) as sole aberration in lymphoid and myeloid malignancies.

Partial gains of chromosome 1q as isolated aberrations are rare occurrences in hematologic malignancies. A recent report of a sole duplication dup(1)(q21q32) in myelodysplastic syndrome (MDS) suggested an inferior prognosis. To further describe structural anomalies involving the 1q21 and 1q32 breakpoints, we present four cases with an inverted dup(1)(q32q21): three in B-cell precursor acute lymphoblastic leukemia (ALL) and one in MDS of the subtype refractory cytopenia with multilineage dysplasia and ringed sideroblasts. In all four cases, the aberration presented as the sole anomaly at diagnosis. In one of the ALL cases, relapse during chemotherapy, 5 months from diagnosis, was accompanied by clonal evolution; in another ALL case, early relapse appeared 51 days after allogeneic stem cell transplantation. Structural gains of 1q involving 1q32 and 1q21 breakpoints can occur in different hematological malignancies. The isolated occurrence of the inverted dup(1)(q32q21) may be interpreted as a typical primary alteration in B-lineage ALL paving the way to acquisition of additional abnormalities. Identification of more cases could further clarify the role of 1q duplications with the q21 and q32 breakpoints in hematological malignancies and better define the prognosis associated with sole aberration in the single entities.