[Experimental study of soft agarose colony formation assay of renal carcinoma]

Several problems have been pointed out in colony formation assay (CFA) developed by Hamburger and Salmon. We studied those using 87 fresh renal carcinoma, comprising of 72 renal cell carcinoma and 15 transitional cell carcinoma of renal pelvis. Results are as follows: Pure single cell suspension was difficult to be yielded from these carcinoma. Our result suggests that cell suspension contains various sized growth unit as well as greater than or equal to 60 microns growth unit. Presence of substantial number of greater than or equal to 60 microns growth unit in plating cell suspension was revealed to influence on the cell growth, ie, the increase of newly formed greater than 60 microns growth unit. This indicates that initial growth unit count is mandatory for "quality control" in CFA. The current study in extent of growth for renal carcinoma revealed three different patterns, one of which did not seem suitable for in vitro chemosensitivity test with CFA. This finding brings for us the fact to prepare "proliferation control" which can check periodically the growth extent of renal carcinoma.