EVALUATION OF CD38 ANTIGEN EXPRESSION IN CHRONIC LYMPHOCYTIC LEUKEMIA: THE EXPERIENCE OF CLINICAL IMMUNOLOGY DEPARTMENT, NATIONAL RESEARCH CENTER FOR RADIATION MEDICINE, NATIONAL ACADEMY OF MEDICAL SCIENCES OF UKRAINE

Abstract

Summary. CD38 antigen is a negative prognostic marker of chronic lymphocytic leukemia (CLL). The question of what cut-off level of CD38 antigen expression should be considered as prognostically significant, remains debatable. Aim: to evaluate the optimal cut-off level for CD38 antigen in primary untreated CLL patients for the prognosis of disease and its association with the mutational status of immunoglobulin heavy chain genes (IGHV genes). Objects and methods: flow cytometric and molecular-genetic analysis (mutational status of IGHV genes using polymerase chain reaction followed by direct sequencing) were performed in the groups of 106 primary previously untreated CLL patients. Time-to-treatment, progression-free survival and overall survival were evaluated using the Kaplan-Meier method and Cox regression. Results: The prognostic value of cut-off level CD38 antigen expression ≥ 20% or ≥ 30% does not differ significantly. Lowering of cut-off level to 7% or 5% was unsignificant. The specificity of the evaluation of the mutational status of IGHV genes based on CD38 antigen expression was low, since CD38 expression in almost half of CLL cases with unmutated IGHV genes not differ from CLL cases with mutated IGHV genes. Conclusion: the obtained data confirmed the prognostic value of CD38 antigen expression in patients at the initial stages of disease (A0-AI), primarily for assessing the duration of overall survival.