Lesser known aquarium fish tumor models

The repeated use of particular species for experimental oncology in fish in creases their future value by accumulating background information for these models and justifies the establishment of genetic stock centers. However, the wide diversity that exists within the class Osteichthyes and Chondricht hyes suggests that the ideal surrogate models for studying some types of ne oplasms might be found among lesser known species. To help assess cultured fish as surrogates for some other types of human neoplasia, we examined cas es in the archives of the Registry of Tumors in Lower Animals and reviewed reports in the literature. Spontaneous and induced neoplasms originating fr om a spectrum of cell types were seen in more than 215 fish species commonl y raised in aquaria or cultured for study among 69 families. prominent fami lies include the Poeciliidae (live-bearers), Cyprinidae (carps and minnows) , Cichlidae (cichlids), Cyprinodontidae (killifish), Characidae (tetras), A drianichthyidae (medakas), Aplocheilidae (rivulins), and Salmonidae (salmon and trout). The following are examples of potential fish tumor models that have received less consideration than some others: papilloma and carcinoma of the urinary bladder in oscar (Astronotus ocellatus); osteogenic neoplas ms, peripheral nerve sheath tumors, and ependymoblastoma in coho salmon fin gerlings (Oncorhynchus kisutch); and nephroblastoma resembling Wilms' tumor in Japanese eels (Anguilla japonica).