If men are using transdermal estradiol for control of ADT-related side effects, does dose matter?

Short-Term Effects of Transdermal Estradiol in Men Undergoing Androgen Deprivation Therapy for Prostate Cancer: A Randomized Placebo-Controlled Trial.

 

Some side effects of ADT, such as hot flushes and bone resorption, are thought to be mediated primarily by the hormone estradiol rather than by testosterone itself.  If patients are taking estradiol to control these side effects, does the dose matter?

Russell et al. randomized 37 prostate cancer patients on ADT to one of three groups:  1) a low-dose transdermal estradiol treatment group using an estradiol gel  2) a high-dose transdermal estradiol treatment group using the same gel and 3) a control group in which participants received a placebo gel (with no active ingredients).  Men who used the estradiol gel, were found to have concentrations of serum (blood) estradiol levels within the range commonly reported for healthy men. Treatment with the estradiol gel was associated with reduced hot flushes and bone resorption with both high and low dose application. A large-scale, randomized, controlled trial confirming the efficacy and safety of “addback” estradiol is now planned.

For more information about this study, see:

 

https://www.ncbi.nlm.nih.gov/pubmed/?term=Short-term+effects+of+transdermal+estradiol+in+men+undergoing+androgen+deprivation+therapy+for+prostate+cancer%3A+a+randomized+placebo-controlled+trial

Russell, N., Hoermann, R., Cheung, A. S., Ching, M., Zajac, J. D., Handelsman, D. J., & Grossmann, M. (2018). Short-term effects of transdermal estradiol in men undergoing androgen deprivation therapy for prostate cancer: A randomized placebo-controlled trial. European Journal of Endocrinology, 178(5), 565-576. doi: 10.1530/EJE-17-1072