[In vitro drug sensitivity test].

Human tumor clonogenic assay(HTCA) not only offers potential advantages for prediction of the sensitivity of individual patients, to anticancer drugs, but also for the development and preclinical testing of prospective new antineoplastic agents. However, HTCA has several theoretical and technical problems, such as a low success rate, the requirement of large numbers of tumor cells and the long time period necessary for evaluation. In order to solve these problems, the MINI-hybrid assay has been developed. We reviewed our experiences to date with chemosensitivity testing by MINI-hybrid assay. Twenty-two of 23 tumors gave evaluable chemosensitivity results (95.6%), and the range of thymidine incorporation for evaluable assays was 7 X 10(2)-1.2 X 10(5)cpm. In addition, the results of drug sensitivity testing of cultured cell lines by MINI-hybrid assay were well correlated with those obtained by HTCA. With its high evaluability rates, the need for fewer cells, the short duration (5 days) required and ease of quantitation, the MINI-hybrid assay is widely applicable to the chemosensitivity testing of human tumors.