Anemia in multiple myeloma.

Anemia is a common complication in patients with multiple myeloma (MM) and occurs in more than two thirds of all patients. The most frequent underlying pathophysiological mechanism is anemia of chronic disease (ACD), relative erythropoietin (EPO) deficiency (due partly to renal impairment) and myelosuppressive effects of chemotherapy, but many other factors may account for or contribute to anemia in myeloma. In patients who achieve complete remission after chemotherapy, anemia usually normalizes. Nonresponders and relapsing myeloma patients often continue to suffer from anemia. Treatment options for anemic myeloma patients include red blood cell (RBC) transfusions and recombinant human erythropoietin (rHuEPO). Red blood cell transfusions convey an immediate effect and rapidly increase the patient's hemoglobin level. Unfortunately, effects of RBC transfusions are only transient and can be associated with several risks, including infections and mild to even life-threatening immunologic reactions. rHuEPO is biologically equivalent to the human endogenous hormone EPO, and its application leads to an increase of hemoglobin levels over an extended time without the risks of blood transfusions. Several studies reported a significant improvement of erythropoiesis, reduction in transfusion need, and improved quality of life by using rHuEPO as long-term treatment of myeloma-associated anemia. Recently, an international expert panel recommended the use of rHuEPO for anemic myeloma patients where other possible causes of anemia have been eliminated.