A chronic myeloid leukemia case with a unique variant Philadelphia translocation: t(9;22;21)(q34;q11;p12)

作者：Al Achkar Walid^*; Wafa Abdulsamad; Moassass Faten; Liehr Thomas

来源：Oncology Letters, 2012, 3(5): 1027-1029.

DOI：10.3892/ol.2012.623

• chronic myeloid leukemia
• variant Philadelphia chromosome
• fluorescence in situ hybridization
• high-resolution array-proven multicolor banding
• imatinib mesylate

The so-called Philadelphia (Ph) chromosome is present in more than 90% of chronic myeloid leukemia (CML) patients. Approximately, 5-10% of these patients show complex translocations involving a third chromosome in addition to chromosomes 9 and 22. Since at present the majority of CML cases are treated with imatinib, variant rearrangements do not exhibit specific prognostic significance. However, events of therapy resistance remain to be studied. In this study, we report a unique case of CML exhibiting an uncommon t(21;22)(p12;q11). This translocation has been characterized by fluorescence in situ hybridization (FISH) and array-proven multicolor banding (aMCB). Using specific probes for the BCR and ABL genes, results of FISH showed a three-way variant Philadelphia translocation (9;22;21)(q34;q11;p12) with a BCR/ABL fusion residing on the der(22) and the 3%26apos;BCR region translocated on the short arm of the derivative chromosome 21. In addition, the aMCB technique is significant in the detection of the breakpoints of genetic changes. The underlying mechanisms and prognostic significance of these changes are discussed.

• 出版日期2012-5