In their correspondence, Orhan and Yalçin raised some important issues with respect to the administration of prophylactic epoetin alfa to cancer patients receiving chemotherapy. Our cost-benefit analysis, as well as other economic evaluations using alternative methodology, have concluded that the general prophylactic use of this drug for all cancer patients receiving chemotherapy may not be cost-effective.1-3 Hence, in our article,1 we suggested that prophylactic epoetin alfa be considered only for selected patient subgroups who would be at high risk for requiring multiple blood transfusions. As described by Orhan and Yalçin, some of these subgroups may include patients with underlying renal, pulmonary, or cardiovascular diseases; older patients; those receiving cytotoxic chemotherapy; and patients who required multiple transfusions in the past. Even though risk factors for anemia have been reported in the literature,4 there has not been a prospective exploratory analysis to predict which cancer patients will likely require blood transfusions. Our group attempted to address this issue by conducting such an analysis with 100 cancer patients using retrospectively collected data.5 Using a multiple logistic regression approach with transfusion requirements (no vs. yes) as the outcome variable, baseline hemoglobin (Hb) level and cisplatin dose were identified as risk factors for future transfusions. Specifically, our model suggested that the need for transfusions increases by 28% for every 10 mg/m2 cisplatin dosage increment. With respect to baseline Hb, patients were 3 times more likely to receive a blood transfusion for every 1 g/dL drop in their prechemotherapy baseline Hb level.5 With these data, we subsequently developed a simple prediction model that could be applied in the clinic to identify patients likely to require transfusions. Once identified, the drug could also be administered to these patients a few weeks before the first cycle of chemotherapy, because it takes approximately 1 month for the drug's benefit to be realized.6 Hence, it may be cost-effective to restrict the use of prophylactic epoetin alfa to the high risk patients identified by the model. The prediction model for transfusion requirements that our group developed has limitations in that retrospective data were used in its development, the sample size was small, the data were obtained from a single center, and it has not been properly validated. Hence, what is required for ensuring that epoetin alfa is used in the most clinically and economically appropriate patient subgroup is the development of a prediction model based on high quality multicenter clinical trial data and with sufficient sample size. A similar instrument for predicting the survival of lymphoma patients has been successfully developed by the Non-Hodgkin's Lymphoma Prognostic Factors Group, which was able to create 4 patient risk groups with 5-year survival as the primary outcome.7 Through the application of Generalized Logit regression modeling,8 we envision a similar categorization of patients receiving cancer chemotherapy, but with need of blood transfusions (i.e., 0 vs. 1–2, 0 vs. >2) as the primary outcome. One practical way of achieving this objective would be to pool the available clinical trial data on epoetin alfa, use the appropriate statistical techniques to create a prediction model, and then validate the final product in the clinic. Our group would fully support such an initiative and would be eager to participate. In summary, epoetin alfa is an important adjunct therapy for patients receiving cancer chemotherapy, but it is not cost-effective to use it in a broad category of patients. The ability to identify which patients are likely to require blood transfusions would be an important step in ensuring that this high cost drug is used in the most clinically appropriate situations. George Dranitsaris M.Sc.Phm.*, * Pharmacoeconomic Research Program, Ontario Cancer Institute, Princess Margaret Hospital, Toronto, Ontario, Canada