Cancer chemotherapy: drug combination and multiple modality treatment

Research has provided many antitumour agents which show varying degrees of effectness against both experimental animal and human cancers. Successful selection of drugs for use in combination can increase antitumour effectiveness. Combination toxicity indices can assist in selecting potentially useful drug combinations. As a result of the first-order kinetics of drug induced tumour cell kill, ability to cure by chemotherapy is inversely related to the size of the tumour population. For chemotherapeutic cure of advanced relatively drug-resistant cancers (animal or human) with existing drugs, there must be prior reduction of tumour burden by alternative treatment methods. In such cases the correct target for present agents is the metastases remaining after noncurative surgery and/or radiotherapy.