ABSTRACT
Introduction of tyrosine kinase inhibitors (TKI) dramatically improves the treatment and survival of the patients with chronic myeloid leukemia (CML) in the last decade. Imatinib (IM) and other TKI induce larger percentage of complete cytogenetic response (CCyR) and major molecular response (MMR). Treatment resistance to TKIs still remains an important problem in the treatment of CML. The aim of our study was to analyze the molecular response (MR) in CML patients treated with Imatinib in our institution. We have analyzed 53 CML patients (pts), 28 females and 25 males, treated with IM as a front or second line treatment. Only 15 pts were treated with IM as a front-line therapy, while 38 pts were pretreated with hydroxyurea or/and interferon. Median duration of CML was 6 years (range: 1 year- 17 years). Median duration of IM treatment was 3 years (range: 1 year-10 years). MR was analyzed in one up to 8 time points with Real Time Quantitative RT-PCR method. Forty six pts (87%) had complete hematological response and 55% of pts had MMR, 13/53(24.5%) pts had MMR at 4.0-4.5 log and 16/53(30.2%) pts had MMR at 3.0-4.0 log. MMR was not achieved in 24/53(45.3%). Our results have shown smaller percentage of patients (55%) with MMR, mostly due to the fact that larger proportion of patients (38/53) were heavily pretreated with HU or/and Interferon for a prolonged period of time, before the IM treatment. This is a major risk factor for acquisition of additional molecular and cytogenetic abnormalities responsible for IM resistance and poor treatment response.
Subject(s)
Antineoplastic Agents/therapeutic use , Biomarkers, Tumor/genetics , Fusion Proteins, bcr-abl/genetics , Imatinib Mesylate/therapeutic use , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Protein Kinase Inhibitors/therapeutic use , Adolescent , Adult , Aged , Disease Progression , Female , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Male , Middle Aged , Real-Time Polymerase Chain Reaction , Remission Induction , Republic of North Macedonia , Time Factors , Treatment Outcome , Young AdultABSTRACT
INTRODUCTION: The clinical course for patients with chronic lymphocytic leukaemia (CLL) is extremely heterogeneous; one of the most important challenges in the clinical management of these patients is the decision on initiating their treatment, but there is no available prognostic system that will resolve this issue. Usually, criteria for active disease are used to initiate therapy. Recently, some authors have proposed prognostic models, scoring systems involving a set of clinical and biological risk factors and estimates of individual patient survivals. Here, we report our initial results from a study designed to evaluate the statistical association of the distinct clinical and biological parameters with the prognosis and time to initiating treatment for patients with CLL. MATERIAL AND METHODS: Our study incorporated 100 consecutive, treatment naive CLL patients. In each patient all traditional laboratory, clinical and biological prognostic factors were evaluated at their first visit to our Institution. We then combined the following independent characteristics: age, ß-2 microglobulin, absolute lymphocyte count, sex, Rai stage, and number of involved lymph node groups, which are included in some of the already published CLL prognostics index, in association with the CD38 expression and mutational status of the immunoglobulin heavy chain gene variable region (IGVH). Further, we correlated those factors by multivariable analysis with time to first treatment. This multivariable model was used to develop a nomogram-a weighted tool to calculate 5- and 10-year survival probability and estimate median time to first treatment (TFT). RESULTS: According to the prognostic index, a classification tree was built that identified three subsets of patients whose scores were 1-3 (low risk - 32 pts - 32%), 4-7 (intermediate risk - 48 pts - 48%) and > 8 (high risk - 20 pts - 20%). Estimated median survival in the low risk subset of patients is 141 years, and 10.7 and 4.6 years respectively in the intermediate and high risk subsets of patients. Projected survival in respectively low, intermediate and high-risk groups are 100%, 100%, 25%, and 43%, 34%, 25% at 5 years and 10 years, respectively. Also, statistical analyses showed that among other things CD38 expression and unmutated IGHV mutation status are associated with a shorter time to first treatment. CONCLUSION: Our prognostic model that combines and correlates the distinct clinical and biological markers of CLL patients enables identification of patients who are at high risk of progression. This prognostic model may facilitate the clinical decision for initiating treatment.
