Masked inv dup(22)(q11.23), tetrasomy 8 and trisomy 19 in a blast crisis-chronic myeloid leukemia after interrupted Imatinib-treatment.

Background: The Philadelphia (Ph) chromosome, or derivative chromosome 22 [der(22)], is a product of the reciprocal translocation t(9;22). It is the hallmark of chronic myelogenous leukemia (CML). It results in juxtaposition of the 5' part of the BCR gene on chromosome 22 to the 3' part of the ABL1 gene on chromosome 9.

A novel cytogenetic abnormality t(7;8)(p11.2:q11.2) and a four-way Philadelphia translocation in an imatinib mesylate-resistant chronic myeloid leukemia patient.

Chronic myelogenous leukemia (CML) is characterized by the Philadelphia (Ph) chromosome, created by a reciprocal translocation t(9:22)(q34;q11) which forms the chimeric gene, BCR-ABL. Variant Ph chromosome translocations involving chromosomes other than 9 and 22 have been identified in 5-10% of CML cases. Four-way Ph chromosome translocations are an extremely rare event in myeloid malignancies and the phenotypic consequences of such rearrangements have not been investigated.

BCR translocation to derivative chromosome 2: a new case of chronic myeloid leukemia with a complex variant translocation and Philadelphia chromosome.

The well-known typical fusion gene BCR/ABL is observed in connection with a complex translocation event in 5-8% of cases of chronic myeloid leukemia (CML). The present study described an exceptional CML case with complex chromosomal aberrations not previously observed. Aberrations included a translocated BCR to the derivative chromosome 2 [der(2)] that also involved a four-chromosome translocation, implying chromosomal regions 1p32 and 2q21, besides 9q34 and 22q11.