Treatment protocols:

Combination-drug chemotherapy is more successful than single-drug treatment in most of the cancers for which chemotherapy is effective. Cytotoxic agents with qualitatively different toxicities, and with diff erent molecular sites and mechanisms of action, are usually combined at full doses.this results in higher response rates, due to additive and/or potentiated cytotoxic eff ects, and nonoverlapping host toxicities. In contrast, agents with similar dose-limiting toxicities,such as myelosuppression, nephrotoxicity, or cardiotoxicity, can be combined safely only by reducing the doses of each.