Cancer-related anemia: pathogenesis, prevalence and treatment

Cancer-related anemia is a cytokine-mediated disorder resulting from complex interactions between tumor cells and the immune system. Overexpression of certain inflammatory cytokines results in shortened survival of red blood cells, suppression of erythroid progenitor cells, impaired iron utilization, and inadequate erythropoietin production. Numerous other factors may also contribute to the development of anemia in cancer patients. The European Cancer Anaemia Survey (ECAS) has provided the most current, comprehensive, prospectively collected data on the incidence and prevalence of anemia among cancer patients, as well as important perspectives on anemia treatment and relationship of hemoglobin and performance status. ECAS enrolled over 15,000 treated and untreated patients with various malignancies from cancer centers in 24 European countries and followed them for up to 6 months. The initial analysis of the ECAS data revealed that 39% of the total cancer patient population was anemic (hemoglobin <12.0 g/dl) at enrollment, although the rate varied according to tumor type, disease status, and cancer treatment status. Of the patients who were not anemic at enrollment and started cancer treatment during the survey, those undergoing chemotherapy--either alone or in combination with radiotherapy--had the highest incidence of anemia (63 and 42%, respectively). Low hemoglobin levels correlated with poor performance status and only 40% of patients who were anemic at some time during the survey received treatment for their anemia. These findings are noteworthy, since a growing body of clinical evidence indicates that the treatment of anemia can significantly improve patients' quality of life and may also improve the clinical outcome.