Additional chromosome aberrations inpatients with chronic myeloid leukemia. I.S.Martynkevich, L.S.Martynenko, M.P.Ivanova, Yu.S.Ogorodnikova, L.A.Dzyavgo, M.V.Moskalenko, E.I.Usachyova, V.Yu.Udalyeva, E.R.Maciulaitiene, Yu.Yu.Mazikova, Yu.S.Bogdanova, O.D.Goncharova, M.N. Krivolutskaya, T.I.Pospelova, A.S.Lyamkina, I.B.Kovynev, Yu.Yu.Chekmeneva, T.P.Zagoskina, A.S.Luchinin, V.A.Ovsepyan, E.G.Lomaia, A.I.Zaritskii, K.M.Abdulkadyrov. Russian Institute of Hematology and Transfusiology, St. Petersburg; I.P.Pavlov State Medical University, St. Petersburg; Altai Territorial Pediatric Clinical Hospital, Barnaul; Municipal Hematological Center, Novosibirsk; Kirov Institute of Hematology and Blood Transfusion. Chronic myeloid leukemia (CML) is a clonal myeloproliferative disease, characterized by the presence of Ph-chromosome in leukemic cells in the majority of patients. Today the first-line therapy for the majority of CML patients is gleevek (c-abl tyrosine kinase inhibitor). We evaluated the significance of additional (other than Ph-chromosome) karyotype disorders (clonal evolution - CE) for the prediction of the disease course and survival of patients with target therapy by gleevek. Additional aberrations were detected at different stages of therapy in 54 (18%) of 277 patients. The patients were divided into 4 groups, depending on the time of emergence of additional chromosome aberrations: with CE in Ph-positive cells before gleevek therapy, with CE in Ph-positive cells during gleevek therapy, with CE in Ph-negative cells during gleevek therapy, and with variant translocations. The presence of CE and variant translocations before therapy was virtually inessential for the development of cytogenetic response in CML patients treated by gleevek, while CE detected in Ph-positive and Ph-negative cells of CML patients by the moment of diagnosis of the minimum residual disease during gleevek therapy significantly deteriorated the results of therapy in comparison with the patients in whom Ph-chromosome was the only aberration detected in cytogenetic analysis of bone marrow cells.