The relationship between serum levels of erythropoietin (EPO) and insulin-like growth factor-1 (ILGF-1) and hematocrit (HCT) in breast cancer patients receiving non-nephrotoxic chemotherapy.

OBJECTIVE: To evaluate the relationship between the hematocrit (HCT), serum erythropoietin (EPO) and insulin-like growth factor-1 (ILGF-1) levels in breast cancer patients receiving non-nephrotoxic chemotherapy.
METHODS: Seventeen patients with stage II breast cancer were included. All received 6 cycles of non-nephrotoxic chemotherapy (cyclophosphamide, 5-fluorouracil and doxorubicin or methotrexate with or without tamoxifen). Insulin-like growth factor-1 and EPO levels were determined before and at the end of therapy. Serum EPO levels were determined by Enzyme linked- immunosorbant assay (ELISA) while those of ILGF- I by radioimmunoassay (RIA).
RESULTS: A significant drop in mean HCT from 37.41%+/-0.77% to 35.18%+/-0.70%, associated with a significant decline in ILGF-1 levels from 92.1+/-15.48 ng/ml to 52.75+/-10.5 ng/ml at the end of the treatment was noted. This association became significant when patients receiving tamoxifen were excluded (r=0.69, p=0.02). The mean serum EPO levels increased significantly from 13.64+/-0.55 U/l to 19.44+/-3.18 U/l and correlated negatively with ILGF-1 level (r=-0.46, p=0.05). There was no significant relation between the serum EPO levels and HCT (r=-0.26, p=0.32).
CONCLUSION: The current data show that ILGF-1 may play an important role in erythropoiesis and it correlates better than EPO with HCT in breast cancer patients receiving non-nephrotoxic chemotherapy.