Advancing perspectives on prostate cancer: multihormonal influences in pathogenesis

Low serum testosterone levels are predictive of prostate cancer

PURPOSE

Although hormones play fundamental roles in prostate growth, their clinical significance is not completely clear. Aims of present study were to assess whether testosterone and serum sex hormone levels are predictors of benign prostatic hyperplasia (BPH) or prostate cancer (PC) and to verify whether prostate cancer is associated with low testosterone levels, and to test association between testosterone levels and known prognostic factors in prostate cancer.

METHODS

In 206 consecutive patients with benign prostatic hyperplasia or prostate cancer testosterone, follicle-stimulating hormone, luteinizing hormone and prolactin levels were tested and correlated with disease. In patients with prostate cancer, hormone levels were also correlated with known prognostic factors. Predictive value was assessed for age, prostate-specific antigen (PSA), PSA ratio, PSA density, prostate volume and serum sex hormone levels using multiple logistic regression analysis and receiver operating characteristic curves.

RESULTS

Considering sex hormones, only testosterone levels were significantly lower in patients with prostate cancer than those with BPH; testosterone levels appear to be independent predictor of prostate cancer, enhancing predictive accuracy for BPH and PC. Testosterone levels do not seem to be associated with known clinical prognostic factors.

CONCLUSIONS

This study supports experimental findings that testosterone levels are predictor of prostate cancer and that prostate cancer is frequently associated with low testosterone levels. In the diagnostic work-up for prostate cancer, adding testosterone determination to PSA test may improve predictive accuracy.

Will GnRH antagonists improve prostate cancer treatment?

Androgen ablation forms a basis for treating prostate cancer and is achieved either by surgical castration, or pharmacologically using oestrogens, anti-androgens and/or gonadotropin-releasing hormone (GnRH) analogues. GnRH antagonists (or blockers) offer a new means of treatment by directly blocking GnRH receptors. Advantages of GnRH antagonists include lack of the initial stimulation of gonadotropin and testosterone production, lack of gonadotropin microsurges and sustained follicle-stimulating hormone suppression; disadvantages include increased histamine release. This review discusses advantages and disadvantages of the GnRH antagonists currently in development, in light of receptor physiology and pre-clinical and clinical data. Comparative clinical trials will ultimately establish their efficacy in comparison to other pharmacotherapies. Therefore, continuing development and refinement is needed to improve prostate cancer treatment.