Hematopoietic growth factors. Defining the appropriate clinical role in multimodality cancer therapy.

Laboratory investigations have begun to elucidate the regulatory molecules that control the processes of blood cell growth and differentiation. Recombinant human colony-stimulating factors are examples of biotechnology-produced molecules that have epitomized the translation of such basic scientific investigation into therapeutic advances. Small cell lung cancer, a malignancy that is overall highly sensitive to aggressive myelosuppressive chemotherapy at initial presentation, has been used as a clinical model in which the activity of human colony-stimulating factors has been tested. In this article, the clinical applications of hematopoietic growth factors are reviewed in brief. The appropriate clinical use of these agents may allow novel therapeutic strategies to be developed in a research setting. Similarly, these agents have the potential to improve supportive care and improve certain clinical outcomes in the non-research clinical care of patients. Issues of cost of treatment are raised by these agents, but the true clinical value of hematopoietic growth factors needs to be studied more rigorously, with emphasis on quality of life and redistribution of care costs outside of hospitals before definitive statements can be made.