Current role of protective agents in cancer treatment.

The administration of intensive chemotherapy according to a rigid schedule improves response rates and duration of response. However, dose-limiting toxicities and resulting delays in therapy often interfere with therapy intensification. In recent years, cytoprotective agents have been developed that can protect normal cells, but not tumor cells, from chemotherapeutic or radiation damage. Amifostine (Ethyol), dexrazoxane (Zinecard), and mesna (Mesnex) are true cytoprotectors administered shortly before chemotherapy. Colony-stimulating factors (CSFs) are administered after chemotherapy to rescue the bone marrow and stimulate hematologic recovery. In the appropriate settings, use of these agents has facilitated the intensification of chemotherapy and has significantly attenuated the impact of chemotherapy on normal cells.