Attempts to optimise colony-forming efficiencies using three different survival assays and a range of human tumour continuous cell lines.

Use of the clonogenic survival assay described by Courtenay has provided the highest colony-forming efficiencies in a range of human tumour cell lines. The improved colony quality obtained with this method facilitates visual counting and results frequently can be obtained within one week. This procedure offers significant advantages over other assays when evaluating the potential of human tumour cell lines as a screening system for predicting drug sensitivities.