Hematopoietic management in oncology practice. Part 2. Erythropoietic factors

As the major regulator of erythropoiesis in man, erythropoietin inhibits the programmed cell death of committed erythroid precursors. In cancer patients, a relative erythropoietin deficiency is coupled with a decreased responsiveness to the substance mediated by the effects of inflammatory cytokines on the marrow and on ferrokinetics, leading to a high incidence of anemia. Two recombinant human erythropoietin (rhEPO) preparations--epoetin alfa (Epogen, Procrit) and epoetin beta (Marogen)--as well as a modified erythropoietic compound (darbepoetin alfa [Aranesp]) are in clinical use. Part 2 of this two-part series on hematopoietic agents reviews the use of these erythropoietic factors and their effect on the anemia that develops in cancer patients. Thrombopoietic factors and progenitor cell-mobilizing factors are also briefly addressed.