Pharmacotherapy of anemia in cancer patients.

Anemia is common in cancer patients who are receiving chemotherapy treatment and may result in symptoms such as fatigue and reduced exercise tolerance. Treatment with recombinant human erythropoietin, an erythropoiesis-stimulating agent (ESA), in anemic patients with solid tumors and nonmyeloid hematological malignancies results in an improvement in mean hemoglobin concentration, a reduction in transfusion requirement along with an improvement in quality of life scores. In patients with myelodysplasia, the response to single-agent ESAs is disappointing but combining ESAs with granulocyte colony-stimulating factor improves the response rates substantially. Unfortunately, a significant proportion of people remain refractory to treatment. Possible causes of ESA refractoriness include true or functional iron deficiency and concomitant intravenous iron supplementation improves response rates when compared with supplementation with oral iron. There are no factors that predict response to ESAs with sensitivity and specificity in people with nonmyeloid tumors, although a promising model for myelodysplasia has been developed that awaits large-scale evaluation. Treatment with ESAs is generally very safe, with just a small increased risk of venous thrombosis. Some recent data have suggested that ESAs may increase the risk of tumor progression in certain settings. These data are worrying but all the trials reporting this outcome have had flaws in design and further data are required.