Quantifying the carcinogenicity of antineoplastic drugs.

It has been well established that many of the drugs used in cancer therapy are themselves potentially carcinogenic. It is therefore important to quantify the carcinogenic risk associated with specific agents, and to investigate ways of predicting their risk from animal and in vitro studies. In this paper, an index of carcinogenic potency is defined, and applied to published data on acute non-lymphocytic leukemia following therapy with cytotoxic drugs used as single agents. Carcinogenic potency estimates for rats and mice are also obtained for 15 antineoplastic drugs, and the potency correlation between humans and rodents is examined for the five agents for which there are data in common. The broader implications for quantitative cancer risk prediction are discussed.