The incidence of submicroscopic deletions in reciprocal translocations is similar in acute myeloid leukemia, BCR-ABL positive acute lymphoblastic leukemia, and chronic myeloid leukemia.

We compared the incidence of submicroscopic deletions accompanying balanced translocations using interphase fluorescence in situ hybridization (FISH) in 245 patients with chronic myeloid leukemia (CML), 79 patients with acute lymphoblastic leukemia (ALL) and BCR-ABL (n=70) or MLL rearrangements (n=29), and 412 patients with acute myeloid leukemia (AML) with CBFB-MYH11 (n=122), PML-RARalpha (n=108), AML1-ETO (n=112), or MLL rearrangements (n=98). The incidence of submicroscopic deletions was 2-9% depending on the entity.