A Novel Four-Way Translocation t(5;9;22;18)(q31;q34;q11.2;q21) in a Patient with Chronic Myelogenous Leukemia

Abstract

Chronic myelogenous leukemia (CML) is characterized by the presence of the Philadelphia chromosome, which is generated by a reciprocal t(9;22) (q34;q11) translocation. Variant Philadelphia chromosomes, found in 5-10% of CML cases, are a result of translocations involving other chromosomes, in addition to 9 and 22. These four-way Philadelphia chromosome translocations are very rare; only about 60 patients with such chromosomes have been described. Here, we report a CML case with a novel four-way variant Philadelphia chromosome. A conventional chromosome analysis of bone marrow cells revealed a 46,XY,t(5;9;22;18)(q31;q34;q11.2;q21) karyotype, which was confirmed by multicolor fluorescence in situ hybridization. The major BCR-ABL1 fusion gene was detected by reverse transcription-nested PCR. The patient was treated with imatinib. Twelve months after treatment, he demonstrated a complete hematologic response and chromosome analysis showed that he had a normal karyotype.Key Words: Chronic myelogenous leukemia, Four-way Philadelphia translocation, Imatinib

Saudi Arabian CML patient with a novel four‐way translocation at t(9;22;5;2)(q34;q11.2;p13;q44)

“…In 2012, a summary of 10 previously reported cases with five‐way translocations of CML was reported (Yokota et al, 2012 ). In some very rare cases, a fourth chromosome can be involved (Asif et al ( 2016 ); Kim et al ( 2015 ); Kubota and Waki ( 2010 )). Finally, in exceptional cases, a fifth chromosome can be involved with t(9;22) (Ikuta et al, 2008 ; Vaidya et al, 2013 ; Yokota et al ( 2012 )).…”