Erythropoietin as a critical component of breast cancer therapy: survival, synergistic, and cognitive applications.

Treatment with recombinant human erythropoietin (epoetin alfa) has been shown to enhance quality of life and cognitive function. The mechanism of action for these changes appears to involve more than the alleviation of cancer treatment-induced anemia. Rather, there is increasing evidence that epoetin alfa treatment may modulate a series of cascading events that involve hypoxia-induced activation of vascular endothelial growth factor and an induction in the expression of vascular endothelial growth factor receptors via a hypoxia-inducible factor-1-mediated transcription among several other hypoxia-related events. The use of epoetin alfa to interfere with this hypoxia-induced cascade could provide significant benefits for cancer patients by enhancing survival through a direct modulation of tumor angiogenesis and effectiveness of cancer therapy. The enhanced quality of life seen with erythropoietin treatment may also involve a modulation of hypoxia-induced decrement in cognitive functioning. It appears that epoetin alfa is a useful addition to the treatment of breast cancer.