Anaemia and its functional consequences in cancer patients: current challenges in management and prospects for improving therapy.

Anaemia is a common occurrence in patients with cancer and contributes to the clinical symptomatology and reduced quality of life (QOL) seen in cancer patients. Many aspects of reduced QOL, including fatigue, are known to be associated with suboptimally low levels of haemoglobin. Even mild-to-moderate anaemia adversely affects patient-reported QOL parameters. Red blood cell transfusions are associated with many real and perceived risks, inconveniences, costs, and only temporary benefits. Recombinant human erythropoietin (rHuEPO) is an effective therapy to increase haemoglobin values in over half of anaemic cancer patients receiving concurrent chemotherapy. These increased haemoglobin values are closely correlated with improvements in QOL. Despite these objectively defined benefits, less than 50% of anaemic patients undergoing cytotoxic chemotherapy receive rHuEPO, in contrast to patients with chronic renal failure on dialysis, where anaemia is universally and aggressively treated to more optimal haemoglobin values. However, there are several barriers that may limit more widespread use of rHuEPO. These include inconvenience associated with frequent dosing; failure of a large proportion (40 to 50%) of patients to respond; relatively slow time to response; absence of reliable early indicators of response; and current lack of rigorous pharmacoeconomic data demonstrating cost-effectiveness. Darbepoetin alfa is a novel erythropoiesis stimulating protein (NESP) that is biochemically distinct from rHuEPO, and which has been proven to stimulate red blood cell production. The molecule has a 3-fold longer half-life and increased biological activity that will allow less frequent dosing, facilitating improved management of the anaemia of cancer. With this new option for therapy, further avenues of investigation should lead to renewed interest in the clinical benefits of optimal haemoglobin levels for patients with cancer.