The current standard hormone therapy (ADT) for men with advanced prostate cancer is a class of drugs called Luteinising hormone-releasing hormone agonists (LHRHa). These drugs reduce serum oestradiol as well as testosterone, causing bone mineral density (BMD) loss as a side effect of the ADT. Using transdermal (skin patches) oestradiol is a potential alternative to LHRHa because it doesn’t have the same negative influence on bone density while still being able to castrate a man.

In an attempt to compare bone mineral density (BMD) changes in men receiving either LHRHa or oestradiol patches (OP) researchers compared the BMD effects of these two types of treatments.

To do this they evaluated men with locally advanced or metastatic prostate cancer participating in the randomized UK Prostate Adenocarcinoma TransCutaneous Hormones (PATCH) and recruited them into a BMD study (2006–2012). They performed dual-energy x-ray absorptiometry scans were performed at baseline, 1 year and 2 year.

They either treated the men with a LHRHa drug as per local practice or gave them OP (FemSeven 100ug/24h patches).

The primary outcome was 1-yr change in lumbar spine (LS) BMD from baseline compared between randomized arms using analysis of co-variance.

Results

From seven different centers they evaluated a total of 74 men with 28 using LHRHa drugs and 46 using OP.

They found that the trans-dermal oestradiol as a single agent produces castration levels of testosterone similar to the LHRHa drugs while also mitigating BMD loss.

http://www.ncbi.nlm.nih.gov/pubmed/26707868