Estrogen receptors (ER, N = 72) and androgen receptors (AR, N = 33) were determined by high pressure liquid chromatography (HPLC) in 72 human prostatic tissues obtained at prostatectomy, and exploratory statistical analyses of the resulting data were performed. To facilitate use of these data as well as other pertinent information from the patient charts, a program for a comparatively large data base was implemented on a Wang minicomputer. The median values of cytosolic AR in the four cancer stages examined were statistically different from each other (P = 0.01), with AR increasing from stages A through D. Even though ER differences between the four stages were not significant (P = 0.13), there was a trend, in the data examined, for median ER values to decrease with stages B through D. On the other hand, median BPH values for both ER and AR were found to lie mid-scale compared with the respective cancer stages, leading to the conclusion that receptor measurements probably cannot distinguish between CA and BPH in human prostatic tissue, at least as measured by competitive binding techniques.