MAMMARY-GLAND NEOPLASIA

Determining how findings of chemically induced carcinogenic effects in rodents can properly he interpreted for human health poses a continui ng challenge to the risk assessment community. One approach begins by comparing and contrasting carcinogenic processes in rodents and humans , identifying biologically significant similarities and differences an d gaps in scientific knowledge and understanding. Russo and Russo (in this issue) use just such an approach to evaluate the current mate of scientific understanding of the comparative mechanisms of mammary tumo rigenesis in humans and rodents, particularly the role of reproductive hormones. This commentary describes the basis for this review and sug gests some of the implications the report may have for human health ri sk assessment and for future research.