Chronic myeloid leukemia is treated successfully with tyrosine kinase inhibitors, providing patients long-term event-free survival and an adequate quality of life. However, mutations of the gene BCR/ABL leads to the formation of resistance to tyrosine kinase inhibitors therapy. Panresistance mutation T315I forms the impossibility of eradicating leukemic clone, at the same time it seems, that this mutation does not reduce the time to progression to acceleration phase and blast crisis. The article presents a review on biology of T315I mutation, and a describes a case of a patient with T315I mutation, and long-term progression-free survival (more than 2,5 years).

CML patient with mutation T315I in accelerated phase, resistant to 2 lines of tyrosine-kinase inhibitors and Aurora-kinase inhibitor, is described. The progression of disease was not rapid. Other 5 patients with similar mutation are described with indolent course of the disease. Short review is presented about incidence of this mutation and its impact on the survival. Survival predominantly depends on the phase of the disease. Optimal treatment strategy is discussed.