Utility of T315I mutation in Egyptian patients with chronic myeloid leukemia

Abstract

ABSTRACT Chronic myeloid leukemia(CML) is a myeloproliferative neoplasm (MPN) characterized by the presence of the Philadelphia chromosome (BCR:ABL), and there is a higher risk in untreated CML to be transformed to blast crisis phase. The development of tyrosine kinase inhibitor (TKI) imatinib was a remarkable step in CML treatment. However, patients showed resistance due to some mutations including T315I which still be the most challenging mutation in CML. Therefore, the aim of our study is to screen T315I in our Egyptian CML patients to predict and determine the frequency of T315I in patients with TKIs resistance. AS-PCR performed on 50 CML patients resistant to the first-line TKIs and 50 CML patients respond to the first-line TKIs. Positive-T315I was found in 15 (30%) of TKIs resistant cases. T315I was significantly associated with higher WBC, platelet count, cellularity of BM aspiration and biopsy when compared to those with negative-T315I. Resistant positive-T315I was significantly associated with lower cumulative OS 55.9% and shorter mean OS 93.4 months when compared to resistant negative-T315I. We conclude that T315I can exist at the diagnosis before starting treatment. Therefore, screening test for T315I can be performed at the time of diagnosis to help in choosing the suitable treatment protocol.