Abstract: A tumor clonogenic assay using soft agar diffusion chambers (ADC) was used to examine 6 kinds of fresh tumor samples obtained from 26 patients. The successful rate of the culture was found to be 65.4%. The coloning efficiency ranged from 0.003% to 0.814%. A significant linear relationship was apparent between the number of tumor cells inoculated and the colonies cultivated (P<0.05). The ADC technigue was used to screen platinum blue. Preliminary experiments showed that this drug may inhibit colony-forming and the results are consistent with those obtained in animal experiments.