Prostate cancer PCa is the second most commonly diagnosed cancer in men. Conventional endocrine treatment for PCa leads to global sex steroid deprivation. The ensuing severe hypogonadism is associated with well-documented adverse effects.
Recently, it has become apparent that many of the biological actions attributed to androgens in men are in fact not direct, but mediated by estradiol. Available evidence supports a primary role for estradiol in vasomotor stability, skeletal maturation and maintenance, and prevention of fat accumulation.
Hence there has been interest in revisiting estradiol as a treatment for PCa. Potential roles for estradiol could be in lieu of conventional androgen deprivation therapy or as low-dose add-back treatment while continuing androgen deprivation therapy. These strategies may limit some of the side effects associated with conventional androgen deprivation therapy. However, although available data are reassuring, the potential for cardiovascular risk and pro-carcinogenic effects on PCa via estrogen receptor signalling must be considered.
Prostate cancer PCa is the second most commonly diagnosed cancer in men, after lung cancer. There is high inter-country variability in prevalence, with less variation in attributable mortality Bourke et al. A variety of approaches have been used: bilateral orchiectomy; high-dose oral or parenteral estrogens; luteinizing hormone-releasing hormone LHRH agonists LHRHa ; LHRH antagonists; androgen receptor AR antagonists, and extragonadal androgen synthesis inhibitors.
LHRHa cause global sex steroid deprivation, with near-undetectable levels of both androgens and estrogens within 30 days of administration Sharifi et al. Loss of E 2 signalling appears to be primarily responsible for certain components of the male hypogonadal syndrome such as vasomotor instability, bone deterioration and fat gain Finkelstein et al. This review will discuss the role of estrogens in the endocrine treatment of PCa. While estrogens have been used extensively in the past as a mode of ADT, they have been replaced in current practice with LHRHa because the latter have been considered a safer and better tolerated alternative.
