The predictive value of short-term screening tests for carcinogenicity

Short term tests are increasingly used to detect mutagenicity and/or possible carcinogenicity. This increasing use is based on the new ideas in chemical carcinogenesis, which have led to the so-called somatic mutation theory.It is emphasized that not all carcinogens will be mutagenic per se especially since two classes of carcinogens can be distinguished, i.e. genotoxic and non-genotoxic or epigenetic carcinogens. The most commonly used short-term tests are those which detect mutagenic action, DNA damage or those which detect malignant transformation in cell cultures.Since most short-term tests lack metabolic activation a metabolic activation system is usually added to the test system. The sensitivity, the specificity and the accuracy of the different short-term test are discussed. The use of a combination of mutagenicity tests usually increases the sensitivity whereas specificity and accuracy usually decrease. The use of a battery of different short-term tests may yield better results with respect to the specificity and accuracy.