A novel five-way translocation t(7;11;9;22;9)(q22;q13;q34;q11.2;q34) involving Ph chromosome in a patient of chronic myeloid leukemia: a case report.

About 5-10 % of chronic myelogenous leukemia (CML) patients show variant Philadelphia (Ph) translocations. The formation mechanisms and clinical significance of variant Ph translocations remain unclear. We report a CML case with a novel five-way complex translocation. Although the result of initial G-banding was 46,XY,t(7;11;9)(q22;q13;q34),t(9;22)(q34;q11.2), fluorescence in situ hybridization (FISH) demonstrated t(7;11;9;22;9)(q22;q13;q34;q11.2;q34) consisting of sequential rearrangements involving five chromosomes. The patient was successfully treated by imatinib and obtained a major molecular response. To our knowledge, this is the tenth CML case with a complicated Ph translocation involving five chromosomes and the third one treated by imatinib. Good response with imatinib therapy suggested that a single-event rearrangement was involved in the chromosomal changes.