Erythropoietin in cancer patients.

Therapy with erythropoiesis-stimulating agents (ESAs) is associated with well-documented benefits to anemic cancer patients undergoing chemotherapy, most importantly a reduction in the likelihood of needing red cell transfusions. One challenge in supportive cancer care is a relative resistance to ESAs, requiring high doses with a significant rate of nonresponse. Recent advances in our understanding of iron metabolism in patients with chronic illness and the results of clinical trials indicate that parenteral iron improves ESA response in this setting. Another issue is the safety of ESA treatment in cancer patients. There is an increased risk of venous thrombosis that must be considered in clinical decision making. There are also recent data raising concerns that ESAs may enhance tumor progression or decrease patient survival. Although the preponderance of the data suggests that ESAs do not alter survival when used to treat chemotherapy-induced anemia, large well-controlled trials addressing this issue are needed.