CML treatment results in Slovenia in the era of tirozin kinaze inhibitors

Abstract

Background: Chronic myeloid leukemia (CML) is a malignant myeloproliferative disorder of hematopoietic stem cells. It is the first malignancy with a known specific chromosomal abnormality, the Philadelphia (Ph) chromosome t(9;22) (q34;q11), which has become a model in the research and treatment of malignant diseases. With the development of targeted drugs, tyrosine kinase inhibitors (TKI) in the 21st century, the strategy of CML treatment has changed completely , and thus also the quality of life and survival. In Slovenia, the use of TKI started in 2002. We show the treatment results in the Slovenian population. Methods: The retrospective analysis included patients with CML treated in all Slovenian hematology centres. We reviewed the period from 2002 to the end of 2011. Patients were divided into three groups: (A) newly diagnosed patients treated between 2002 and 2006, (B) newly diagnosed patients from January 2007 until the end of November 2011, and (C) all patients together. As the guidelines for the treatment of CML werepublished in 2006, we decided for this distribution of patients in order to find out whether our treatment results were any better because of that. Results: From early 2002 until the end of 2011, 164 new patients with CML were detected in Slovenia (group A-74, Group B–92). In group A, 56 (76 %) patients are still alive, 18 (24 %) have died , and 46 (62 %) reached major molecular response. Overall survival of patients after nine years of treatment is 80 %. Out of 12 patients with HSCT, 6 are alive. In group B, 85 patients are alive (91 %), major molecular response was achieved in 49 patients (52 %), 25 have been treated for less than 18 months and the result is not relevant. In this period none of the patients had HSCT. Fouryear survival is 81 %. In the total group of patient (C), major molecular response was achieved in 64 % of patients, in 75 % with imatinib. Because of intolerance or no response to imatinib, 25 % of patients are receiving second-generation tyrosine- kinase inhibitors, dasatinib in 20 % and nilotinib in 80 %. Conclusions: Treatment results of the Slovenian CML patients’ population are comparable with those published in the literature. Since this is an entirely retrospective study, many data are lacking, which is disturbing. From this point, it is important to revive the Slovenian registry of CML patients’ population.