JAPANESE MEDAKA LIVER TUMOR MODEL: REVIEW OF LITERATURE AND NEW FINDINGS.
The Japanese medaka liver tumor model provides a rapid, in vivo screen for laboratory testing the carcinogenicity of aquatic pollutants. The high yield of tumors and associated brief induction period are strong arguments for using this model as an initial indicator in a multitiered testing program. Future studies to biologically characterize the medaka liver tumor(s) are needed. In addition, screening of a variety of compounds including proven mammalian carcinogens, promoters, cocarcinogens, weakly positive carcinogens, compounds considered negative, and compounds that may afford protection against carcinogenesis should be conducted. For other features of the medaka model and for a more complete discussion concerning fish as test organisms in carcinogenicity studies, the consensus report should be consulted.