Blast phase of chronic myeloid leukemia with concurrent BCR::ABL1 and SET::NUP214: A report of two cases.

ABSTRACT

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm defined by the presence of t(9;22)(q34;q11.2)/BCRABL1. Additional chromosomal abnormalities play an important role in the progression to CML. However, the additional fusion gene was rarely reported such as CBFBMYH11. In this report, we described two cases of the co-occurrence of BCRABL1 and SETNUP214 in CML-BP for the first time, which is associated with poor outcomes during tyrosine kinase inhibitor (TKI) treatment. Meanwhile, we retrospectively analyzed SETNUP214 fusion transcript of the two cases at initial diagnosis of the CML chronic phase by quantitative RT-PCR, and detected at a ratio of 1.63% and 1.50%, respectively. SETNUP214 may promote disease progression during the transformation of CML. This study highlights the importance of extended molecular testing at the initial diagnosis of CML-CP at TKI resistance and/or disease transformation.