Growth of human renal carcinoma in soft agar colony formation assays measured by computer-assisted volume analysis.

Technical methods for assessing the growth and chemotherapy sensitivity of human tumor cells growing in soft-agar culture have been less than ideal. Within the past year, there have been reports of studying the extent of growth of human tumor cells in these cultures by quantitating the change in cumulative volume for the growth units observed. The present report describes the results of computer-assisted volume analysis applied to soft-agar cultures of cells from 74 primary renal cell carcinomas, 14 primary transitional cell carcinomas of the renal pelvis, and four different human renal cell carcinoma xenografts. The extent of growth in vitro observed for cells from freshly excised human renal tumors showed the expected and statistically significant relationship to tumor grade and stage. The renal cell carcinoma xenografts proliferated to a much greater extent in vitro than the cells from freshly excised human renal carcinomas. The fundamental growth limit of 10(9) micron. cumulative growth unit volume per plate was confirmed by this series of experiments. Computer-assisted volume analysis appears to be a useful method to study the growth of freshly excised human renal carcinoma cells in vitro.