It is well recognized that anemia-induced tumor hypoxia is associated with a reduced sensitivity of tumors to radiation and some forms of chemotherapy. Thus, the correction of lower hemoglobin (Hb) concentrations with recombinant human erythropoietin (rHuEPO) can play an essential role by improving tumor oxygenation. Based on evidence from a number of trials, treatment with rHuEPO will effectively ameliorate anemia and improve quality of life. However, one of the most essential prerequisites for achieving this benefit is the use of rHuEPO in agreement with the evidence-based ASCO/ASH-guidelines recommending a target Hb concentration of 12 g/dl (7.44 mmol/l).