Systematic review of controlled trials on erythropoietin to support evidence-based guidelines

To support evidence-based clinical guidelines on erythropoietin use for anemia in oncology, we conducted systematic reviews of controlled trials on four patient groups. These were patients with treatment-related anemia; patients with disease-related anemia; patients transplanted with allogeneic hematopoietic stem cells; and those transplanted with autologous hematopoietic stem cells. Two reviewers followed a prospective protocol to select studies, abstract relevant outcomes, evaluate study quality, and conduct meta-analysis where data sufficed. For treatment-related anemia, meta-analysis of available evidence (22 trials; N = 1,927) demonstrated reduced odds of transfusion after erythropoietin, but higher-quality trials reported smaller odds reductions. In several trials, erythropoietin improved quality of life for groups with mean baseline hemoglobin < or = 10 g/dL. However, evidence was insufficient to determine whether initiating erythropoietin treatment earlier for newly anemic patients reduced the odds of transfusion or improved quality of life more than waiting until hemoglobin approached l0 g/dL. Limited evidence (6 trials; N= 693) suggested that erythropoietin decreased the risk of transfusion for patients with disease-related anemia. For those undergoing allotransplants, evidence (7 trials; N = 493) showed erythropoietin modestly decreased time to red cell engraftment and transfusions. Studies on erythropoietin after autologous transplants (6 trials; N = 321) did not support a beneficial effect of erythropoietin.