ALBERT

Description: Introduction: Imatinib mesylate (IM) is the first tyrosine kinase inhibitor (TKI) licensed for the treatment of chronic myeloid leukemia (CML). Severe bone marrow fibrosis (BMF) has been reported in excess of 40% of the patients with CML at diagnosis. Before TKIs became available, BMF which emerged at diagnosis and/or in the late periods of the disease was defined to be a poor prognostic factor, and it contributed significantly to morbidity and mortality from 10% to 30% in patients with CML. The relationship between BMF and both disease progression and prognosis has been the subject of re-evaluation after the introduction of IM therapy. In patients with CML, it has not been clearly demonstrated yet, whether IM improves the poor prognostic effect of fibrosis, and prevents the new BMF development or not. Aim: The purpose of this study was to evaluate the effects of IM therapy on BMF formation, and the prognostic significance of BMF in patients with CML. Material and Methods: One hundred and thirty-five CML patients were enrolled in the study. Patients' demographics, Sokal risk scores, molecular and cytogenetic responses and follow-up periods were noted from the patients' files retrospectively. All pre- and post-IM bone marrow biopsy samples, which were stained with hematoxylin and eosin, were re-evaluated for the current analysis. Grading of BMF was according to the European consensus decisions, graded as 0-III. The term "last bone marrow biopsy" (LBMB) is referred to a biopsy, which was performed at 18th months or later on during IM treatment. Results: The median age was 44 years (range, 18-92 years), and 78 patients (58%) were male. One hundred and twenty-eight patients (95%) were in chronic phase [CP], 4 patients (3%) were in accelerated phase [AP], and 3 patients (2%) were in blast crisis [BC] at the time of IM initiation. Out of 128 CML-CP patients, one hundred and twenty patients (93%) were in early CP, whereas 8 (7%) were in late CP. The percentage of low, intermediate, and high Sokal risk scores were 35%, 43%, and 22%, respectively. Before IM was initiated, thirty-one patients had received previous treatment modalities (hydroxyurea (HU) in twenty-one, and 10 patients had received interferon plus HU. he median duration of IM treatment was 45 months (range, 2-106 months). The rates of complete hematological response (CHR) at 3rd month, complete cytogenetic response (CCyR) at 12th month, and major molecular response (MMR) at 18th month were 92.4%, 71.6%, and 67.6%, respectively. BMF before the initiation of IM therapy was grade 0 in 52 patients (39%), grade I in 39 patients (29%), grade II in 28 patients (21%), and grade III in 16 patients (12%). There was a positive correlation between the Sokal risk scores and the grades of BMF at diagnosis (r:0.313, p

Description: Abstract 4429 Background Imatinib mesylate (IM) is considered the mainstay of chronic myeloid leukemia (CML) treatment for almost a decade. The primary goal of the study is to share data of a substantial number of CML patients followed at one center. Methods We analyzed data from 177 CML patients who were treated in our institution and received IM for at least 24 months. They were stratified into low, intermediate and high risk groups based on Sokal score. Early chronic phase (ECP) (within one year from diagnosis to IM start), late chronic phase (LCP) (≥ 12 months from diagnosis), and accelerated phase (AP) CML patients were included in the study. Patients were evaluated for hematologic, cytogenetic and molecular responses, event-free survival (EFS) and overall survival (OS), frequency of adverse events. Results The median age was 51.2 years (range, 22–86 years), with 77 females and 100 males. Patients were followed for a median of 60 months (range, 24–116 months). IM was started at a dose of 400 mg daily. 97.7% were in chronic phase, and 2.3% were in accelerated phase.75.1% of chronic phase CML patients were in early and 24.9% in late chronic phase. 42% of patients were low Sokal risk, 44% intermediate and 14% were high risk patients. 12% of the patients did not receive any prior therapy, 1% had received prior therapy with interferon (IFN), 73% were treated with hydroxyurea (HU) (mostly short course) and 14% with both HU and IFN. Complete hematologic response (CHR) was achieved in 90% of patients at 3 months (median time, 2.02 months). Cumulative rates of cytogenetic and molecular responses at 6, 12, 18 and 24 months are summarized in Table 1. Complete cytogenetic response (CCyR) was achieved in a significantly higher proportion of patients within the low and intermediate Sokal risk group (79.4%, 85.2%) compared with the high risk patients (14.3%, p=0.001). There was a significant difference in the complete molecular response (CMR) ratio achieved by low, intermediate and high Sokal risk patients (70.4%, 63.8% and 33.3%, p