Testosterone therapy: a friend or a foe for the aging men with benign prostatic hyperplasia?

Historically, testosterone (T) has been regarded as a detrimental hormone for the prostate in ageing men. This concept is based on the known effect of T in the prostate growth during fetal life and puberty. However, the role of T in the prostate growth during adulthood is not proven. Epidemiological studies show that the increasing prevalence of benign prostatic hyperplasia (BPH) with ageing is paralleled by a progressive decline in T. Moreover, a relationship between BPH and metabolic syndrome (MetS) is documented. Experimental data confirm that MetS and dyslipidemia can induce histopathological features of BPH, including prostate inflammation. The well-known association between MetS and hypogonadism, and the amounting evidence on the anti-inflammatory function of this hormone, arises the hypothesis that low T, occurring in adults with MetS, could favor the development of BPH driven by metabolic stimuli. Data from an animal model of MetS seem to confirm this hypothesis, showing that T treatment can prevent the histopathological features of BPH in MetS rabbits. In men, there is reassuring evidence that T therapy in hypogonadal men does not worsen lower urinary tract symptoms. However, there are only a few data on the effect of T therapy on prostate tissue. Based on the available evidence, T therapy cannot be considered a threat for the prostate. Although specifically designed trials are needed, it is likely that in the next future we will assist to a transition of T from the side of the enemies of the prostate to that of the allies.