USE OF ERYTHROPOIETIN IN ONCOLOGY

Anemia is a common complication observed in cancer patients. Its etiol ogy is multifactorial and its severity depends on patient characterist ics, type and stage of neoplasia, type of used chemotherapy. Erythropo ietin can be effective by counteracting two of the main causes of anem ia in cancer patients undergoing chemotherapy: 1. Myelosuppression Ind uced by chemotherapy. Almost all cytotoxic drugs induce this effect. I n this circumstance erythropoietin can be effective by accelerating th e recovery of the erythroid compartment spared by chemotherapy. For th is effect, higher than physiologically normal levels of erythropoietin are required. 2. Endogenous erythropoietin deficiency secondary to re nal impairment. Renal impairment is primarily induced by cisplatin and leads to a deficient renal production of erythropoietin. In this case , erithropoietin administration can be considered as a hormone replace ment therapy. Possible indications for the use of erythropoietin in ca ncer patients are the following: 1. Prevention of anemia; 2. Treatment of anemia induced-by either high dose chemotherapy and bone marrow tr ansplantation (BMT) or standard dose chemotherapy. The preventive use of erythropoietin is still under investigation. Two randomized studies reported the erythropoietin ability to prevent the anemia development . Further trials are required to identify subsets of patients in which the preventive use of the drug could be cost-effective. One of the ca uses of anemia after allogeneic BMT is the endogenous production of er ythropoietin Inappropriately low for the degree of anemia. On the cont rary, after autologous BMT the erythropoietin response to anemia is ap propriate. Phase III randomized studies showed the efficacy of erythro poietin in the treatment of anemia after allogeneic but not after auto logous BMT. After standard dose chemotherapy, phase III randomized stu dies showed that erythropoietin is able to correct anemia in 60-80% of patients receiving platinum-based chemotherapy and in nearly 40% of p atients receiving chemotherapy without platinum. The correction of ane mia leads to a significant reduction in transfusion requirement. In so lid tumors erythropoietin is commonly administered at the schedule of 150 U/Kg subcutaneously three times per week. Normal levels of current iron supply should be guaranteed by oral iron support during erythrop oietin treatment. Because the response to erythropoietin occurs after a median time of 5 weeks, it is necessary to start erythropoietin ther apy at an hemoglobin level higher than that triggering transfusion. Va rious parameters, at baseline or after 2-4 weeks of erythropoietin the rapy, have been evaluated as predictors of response. However, other pa rameters should be studied to identify stronger predictors.Conclusions . Erythropoietin treatment is recommended after allogeneic BMT. Erytro poietin is effective in 60-80% of anemic patients receiving platinum-c ontaining chemotherapy and in approximately 40% of patients receiving chemotherapy without platinum. The preventive use of erythropoietin is still under investigation. Further studies should identify subsets of patients and types of chemotherapy in which the prevention of anemia could be cost/effective.