Androgens are essential for the development and maintenance of the prostate. However, prostatic growth may be mediated by epidermal growth factor (EGF) and the expression of the EGF receptor (EGFR) may be influenced by the androgenic milieu. We have characterized the expression of cytosolic androgen receptor (ARc), nuclear salt extractable androgen receptor (ARn) and EGFR in 89 consecutive cases of benign prostatic hyperplasia, 84 of which were treated by transurethral prostatic resections. Image analysis morphometry was performed on the histological sections to determine the epithelial content of the gland. Our results indicate that there is a vast heterogeneity of receptor expression in benign prostatic hyperplasia. Expression of ARc ranged from zero to 1312 fmol/gm. tissue (mean +/- SD 265 +/- 290), ARn ranged from zero to 531 fmol/gm. tissue (mean +/- SD 145 +/- 98) and EGFR ranged from zero to 316 fmol/gm. tissue (mean +/- SD 121 +/- 76). A statistically significant association was found between expression of ARn and EGFR, and these were both significantly correlated with the epithelial content of the gland.