Transfusion of allogeneic blood products carry a small but not negligible r
isk for the transmission of infections and may have immunosuppressive or im
munogenic effects. The discovery, licensing, and clinical use of hematopoie
tic cytokines such as erythropoietin or thrombopoietin may reduce the requi
rements for allogeneic blood transfusions. However, the effectiveness has s
o far only been demonstrated in limited clinical situations. Further progre
ss in avoiding allogeneic transfusions can be expected from the development
of artificial blood cell substitutes. The potential and limits of these ne
w techniques and substances to manage pancytopenia in cancer patients are r
eviewed briefly.