Cytogenetic documentation of DHL. (A) Classical cytogenetics shows a complex karyotype with presumptive MYC/IGH and BCL2/IGH translocations. (B) The MYC translocation is confirmed with interphase FISH studies using a break-apart probe that shows one normal fused signal and one set of separated red and green signals. (C) The BCL2 translocation is confirmed with interphase FISH studies using a break-apart probe. There is one normal cell on the right with 2 fused signals and an abnormal cell with 1 fused and 1 set of separated red and green signals. (Figure contributed by U. Surti and M. Sherer.)