The role of intravenous iron in the treatment of anemia in cancer patients

Anemia is a major cause of morbidity in cancer patients resulting in poor physical performance, prognosis and therapy outcome. Initially, erythropoietin-stimulating agents (ESAs) were supposed to be the treatment of choice but about one third of patients turned out to be nonresponders and meta-analyses provided evidence of an increased risk of mortality if used excessively. This along with the successful use of intravenous iron for anemia in patients with chronic kidney disease prompted seven clinical studies evaluating the efficacy of intravenous iron as an adjunct to ESAs and four additional studies using intravenous iron only for anemia in cancer patients. These studies confirmed a superior response if ESAs are combined with intravenous iron and revealed iron only to be a useful option in patients with mild and absolute iron deficiency (AID). Currently, best treatment decisions for anemia in cancer might be based on measurements of serum ferritin (SF), transferrin saturation (TSAT), soluble transferrin receptor (sTfR), ferritin index (FI = sTfR/log SF), hypochromic reticulocytes (CHR) and C-reactive protein (CRP). However, there is still an urgent need for trials investigating diagnostic approaches to optimize therapy of anemia in cancer patients with iron and/or ESAs.