The role of tissue steroids in benign hyperplasia and prostate cancer

: This paper presents a large body of data relating to benign prostatic hyperplasia, which have been derived from fundamental endocrinological research. For the urologist, the data open up interesting aspects of the pathomorphology of prostatic hyperplasia. The most interesting findings can be summed up as follows: 1. Testosterone is the circulating androgenic prohormone that mediates the intracellular message leading to androgen secretion, though by way of its metabolite dihydrotestosterone, which is really the active substance. 2. This metabolic conversion is catalyzed by 5 alpha-reductase, which is predominantly a stromal enzyme. 3. The estrogen metabolism in the stromal cells of the prostate may be associated with the abnormal growth of the prostate. 4. In the presence of benign prostatic hyperplasia dihydrotestosterone and 17 beta-estradiol accumulate in the nuclei of the stromal cells. 5. Adrenal androgens are also metabolized in the human prostate, yielding some substances with androgenic and some with estrogenic potency. 6. Changes in sex hormone binding globulins (SHBG) are found with age whether benign prostatic hyperplasia is present or not. It is therefore questionable whether it has any influence on the development of prostatic hyperplasia. 7. Although in some cases it is not yet possible to determine whether the findings presented in this paper have any causal significance, the data can be used as a rational basis for hormonal treatment of prostatic disease.