Involvement of the Y chromosome in numerical changes associated with acute nonlymphocytic leukemia is quite common, whereas acquired structural rearrangements of the Y chromosome are much rarer, there being only four such cases documented in the literature [1]. We identified a case of acute myeloid leukemia (AML M2) with rearrangements of chromosomes 1, 10, and Y; at remission, all analyzed metaphases were normal, confirming the acquired nature of the Y chromosome abnormality.