Luteinising hormone-releasing hormone agonists (LHRHa), used as androgen deprivation therapy (ADT) in prostate cancer (PCa) management, reduce serum oestradiol as well as testosterone, causing bone mineral density (BMD) loss.
Transdermal oestradiol is a potential alternative to LHRHa.
To compare BMD change in men receiving either LHRHa or oestradiol patches (OP).
Men with locally advanced or metastatic PCa participating in the randomised UK Prostate Adenocarcinoma TransCutaneous Hormones (PATCH) trial (allocation ratio of 1:2 for LHRHa:OP, 2006-2011; 1:1, thereafter) were recruited into a BMD study (2006-2012). Dual-energy x-ray absorptiometry scans were performed at baseline, 1 yr, and 2 yr.
LHRHa as per local practice, OP (FemSeven 100μg/24h patches).
The primary outcome was 1-yr change in lumbar spine (LS) BMD from baseline compared between randomised arms using analysis of covariance.
A total of 74 eligible men (LHRHa 28, OP 46) participated from seven centres. Baseline clinical characteristics and 3-mo castration rates (testosterone ≤1. 7 nmol/l, LHRHa 96% [26 of 27], OP 96% [43 of 45]) were similar between arms. Mean 1-yr change in LS BMD was -0. 021g/cm(3) for patients randomised to the LHRHa arm (mean percentage change -1. 4%) and +0. 069g/cm(3) for the OP arm (+6. 0%; p<0. 001). Similar patterns were seen in hip and total body measurements. The largest difference between arms was at 2 yr for those remaining on allocated treatment only: LS BMD mean percentage change LHRHa -3. 0% and OP +7. 9% (p<0. 001).
Transdermal oestradiol as a single agent produces castration levels of testosterone while mitigating BMD loss. These early data provide further supporting evidence for the ongoing phase 3 trial.
This study found that prostate cancer patients treated with transdermal oestradiol for hormonal therapy did not experience the loss in bone mineral density seen with luteinising hormone-releasing hormone agonists. Other clinical outcomes for this treatment approach are being evaluated in the ongoing PATCH trial.
ISRCTN70406718, PATCH trial (ClinicalTrials. gov NCT00303784).
European urology. 2015 Dec 17 [Epub ahead of print]
Ruth E Langley, Howard G Kynaston, Abdulla A Alhasso, Trinh Duong, Edgar M Paez, Gordana Jovic, Christopher D Scrase, Andrew Robertson, Fay Cafferty, Andrew Welland, Robin Carpenter, Lesley Honeyfield, Richard L Abel, Michael Stone, Mahesh K B Parmar, Paul D Abel
Medical Research Council Clinical Trials Unit at University College London, London, UK. Cardiff School of Medicine, Cardiff University, Cardiff, UK. , The Beatson West of Scotland Cancer Centre, Glasgow, UK. , Medical Research Council Clinical Trials Unit at University College London, London, UK. , Freeman Hospital, Newcastle upon Tyne, UK. , Medical Research Council Clinical Trials Unit at University College London, London, UK. , Ipswich Hospital NHS Trust, Ipswich, UK. , Scarborough General Hospital, Scarborough, UK. , Medical Research Council Clinical Trials Unit at University College London, London, UK. , Medical Research Council Clinical Trials Unit at University College London, London, UK. , Medical Research Council Clinical Trials Unit at University College London, London, UK. , Imperial College Healthcare NHS Trust, London, UK. , Imperial College London, London, UK. , Cardiff University, Bone Research Unit, Penarth, UK. , Medical Research Council Clinical Trials Unit at University College London, London, UK. , Imperial College Healthcare NHS Trust, London, UK; Imperial College London, London, UK.