Erythropoietin-stimulating agents in oncology

Erythropoiesis stimulating agents (ESAs) are some of the most widely used agents in oncology. Yet, the use of ESAs to treat chemotherapy induced anemia in cancer patients has raised issues of concern since 2003, when the two initial studies that were powered to detect meaningful differences in survival with ESA therapy were either halted early, or concluded with deleterious effects on survival. Several trials since then have caused both guideline writers and the FDA to recommend that ESAs should not employed to drive the hemoglobin to greater than 12 g/dL. It is still unclear what role these agents will play in cancer patients with hemoglobin of less than 12 g/dL. In myelodysplastic syndrome, however, these agents are likely part of a core of supportive care measures for low-grade disease, and need to be readily available for these patients. In this review, we attempt to describe the relevant experimental data on ESAs, their current role in clinical oncology, and the research and discoveries that may widen the scope, and enhance the benefit of these agents.