Prevalence and Clinical Characteristics of Paraproteinemia Associated with Chronic Myeloid Leukemia

Abstract

<b><i>Introduction:</i></b> Data regarding the prevalence of paraproteinemia in patients with chronic myeloid leukemia (CML) are lacking. <b><i>Methods:</i></b> To evaluate for the prevalence of paraproteinemia, we undertook this cross-sectional study among consecutive chronic-phase CML patients. Complete blood count, chemistry, immunoglobulins, serum-free light chains, serum-protein electrophoresis and immunofixation were collected. Further analyses evaluated whether various patient-, disease-, and treatment-related variables are associated with paraproteinemia. <b><i>Results:</i></b> One hundred patients, median age 63.5 (IQR 48.1–72) years were recruited. Median time from CML diagnosis to enrollment was 6.3 (IQR 2.3–11.3) years. Monoclonal protein was detected in 8 patients (8%), diagnosed with smoldering multiple myeloma (SMM, <i>n</i> = 2) and low-risk monoclonal gammopathy of undetermined significance (MGUS, <i>n</i> = 6). Six patients were on tyrosine kinase inhibitor treatment, 2 were in treatment-free remission. The only covariate associated with paraproteinemia was the presence of anemia, albeit with borderline statistical significance in univariate analysis (<i>p</i> = 0.053) and when adjusted for age (<i>p</i> = 0.056). <b><i>Conclusions:</i></b> In this largest study so far describing the prevalence of paraproteinemia among CML patients, we found MGUS prevalence to be higher than the 3.2% expected prevalence in the general population above 50 years and a non-negligible prevalence of SMM (2%). Screening for paraproteinemia in CML patients, especially in the presence of anemia, should be considered.