[Assessment of chemosensitivity tests of human tumor cells]

It is clear that if we could predict a sensitive drug against an individual tumor the therapeutic effect would be much improved. For this purpose, many kinds of chemosensitivity test have been devised and investigated. The five kinds of test used currently are based on the measurement of enzyme activities (enzyme assay), measurement of inhibition of radioactive precursors incorporation, and measurement of clonogenic cells in a tumor cell population. In vivo assay systems are xenografts of human tumor in nude mouse and the subrenal capsule of the mouse (SRC assay). In vivo and in vitro correlations reported by several authors are summarized in which positive predictivity rate revealed around 50% and negative 90%. Among five kinds of chemosensitivity test enzyme assay and SRC assay are recommended for clinical use.