A randomized trial in patients with advanced lung cancer adds to evidence of reduced survival among erythropoietin recipients.
Erythropoietin is used to treat anemia and improve quality of life in cancer patients receiving chemotherapy. However, erythropoietin has been associated with decreased survival in several recent cancer treatment trials. Now, another study raises concern.
Canadian researchers randomized patients with advanced non-small-cell lung cancer and hemoglobin levels of 12 g/dL or lower to receive erythropoietin or placebo (target hemoglobin, 12–14 g/dL). Patients did not receive chemotherapy during the trial, although 23% had received it previously. After 70 patients had enrolled, the trial was interrupted when significantly decreased survival was noted in the erythropoietin group compared with the placebo group (median survival, 63 vs. 129 days). Nearly all deaths were attributed to progressive lung cancer. Hemoglobin levels rose by 1.5 to 2.0 g/dL in the erythropoietin group, and were unchanged with placebo.
Comment: In this study, the decreased survival noted with erythropoietin could have occurred by chance, given the small number of patients. However, the investigators chose to stop the study given that two other recent trials — involving patients with breast or head-and-neck cancer — also suggested reduced survival among erythropoietin recipients. In addition, a recent meta-analysis of studies on erythropoietin therapy in cancer patients suggested a significantly increased risk for thromboembolic events (relative risk, 1.67), and a near-significant increase in mortality (hazard ratio, 1.08). The mechanism by which erythropoietin increases mortality in cancer patients — assuming that the relation indeed reflects cause-and-effect — remains unclear.
— Allan S. Brett, MD
Published in Journal Watch General Medicine April 17, 2007