Evaluation of anemia after long-term treatment with imatinib in chronic myeloid leukemia patients in chronic phase

Abstract

Introduction: The incidence of grade 3–4 anemia was reported to be 3% with imatinib therapy for newly diagnosed chronic myeloid leukemia (CML) in the chronic phase (CP). However, there are few data regarding the causes and the development of anemia after long-term treatment. This study aimed to evaluate the incidence of anemia after at least two years of imatinib treatment of CML patients in the CP and to identify other contributing causes of anemia in this population. Patients and methods: We performed a retrospective analysis of 97 CML patients in the CP treated with imatinib for at least two years. We analyzed the hemoglobin (Hb) levels of CML patients at diagnosis, upon initiation of treatment with imatinib and after two years of imatinib treatment, and investigated other causes of anemia in this population. Results: Most of the patients presented Hb levels below the normal range (80.4%) after the second year of treatment, 17.9% grade 2 and 1.3% grade 3. In 13 cases (16.7%), anemia was attributed to resistance and in 13 cases (16.7%) the following causes were identified: iron deficiency (n = 5), hypothyroidism (n = 2), vitamin B12 deficiency (n = 3), acquired immune deficiency syndrome (AIDS) (n = 1), pulmonary tuberculosis (n = 1) and renal toxicity (n = 1). In 52 patients (66.6%), there were no other factors contributing to anemia, except imatinib treatment. Conclusion: Regular follow-up is required to identify the causes of anemia not related to CML or imatinib toxicity. The importance of investigating secondary causes of anemia should be emphasized, especially in patients with good adherence to treatment and satisfactory therapeutic response. Keywords: Chronic myeloid leukemia, Imatinib, Anemia, Adverse events