The role of erythropoietin (EPO) plus granulocyte-colony stimulating factor (G-CSF) combination in hemopoietic recovery was studied in patients with high-risk breast carcinoma and compared to a control group of previously treated identical patients who were not given EPO plus G-CSF. Eleven consecutive patients admitted to this study had Stage III or IV breast cancer. They received 6 cycles of intensive chemotherapy (epirubicin 150 mg/m2 and cyclophosphamide 1300 mg/m2). The 1st cycle served for mobilization of peripheral blood progenitor cells (PBPC). At its end leukaphereses collections of PBPC were performed to be used as hematologic support (PBPCT) in the 5 remaining cycles. The administration of EPO plus G-CSF was started when leukocyte (WBC) count in peripheral blood dropped below 1 x 10(9)/l and hemoglobin (Hb) level fell below 100 g/l. The treatment was stopped when leukocyte count rose to 5 x 10(9)/l and Hb to 130 g/l. EPO plus G-CSF combination after PBPCT produced significant effects in terms of hemopoietic recovery, clinical benefit and supportive care requirements when compared with 12 historic control patients: Periods of leukopenia were shorter which resulted in reduced risk of infectious complications. The grades of leukopenia in the study and control groups were as follows: grade 4 (36 vs. 18%), grade 3 (57 vs. 30%), grade 2 (7 vs. 13%) respectively. Significantly shorter was the time of PLT recovery < 50 x 10(9)/l (p < 0.001). The grades of thrombocytopenia were: grade 4 (29 vs. 11%), grade 3 (21 vs. 12%), grade 2 (25 vs. 36%) respectively. The number of necessary transfusions was significantly reduced as well as the length of hospital stay (p < 0.001). In conclusion, our results obtained in this study confirm that combination of EPO plus G-CSF not only increases the rate of hemopoietic recovery, reduces the number of necessary red blood cell and platelet transfusions but, at the same time, simplifies the clinical management and is more tolerable for the patients.