The PATCH trial is one of the arms of the original STAMPEDE trial. It was comparing the performance of standard LHRH hormone therapy (Zoladex, Prostap, Decapeptyl, Degaralix) with Estradiol patches, which use Estradiol (the main estrogen) to suppress Testosterone. These same patches are used for HRT in post-menopausal women. It did not include metastatic patients, and it's threshold level for Testosterone suppression was relatively high at 1.7nmol/L (LHRH hormone therapy usually does significantly better, and I can't see how that compares with the levels achieved on Estradiol in the trial).
The trial has just reported, and found the effectiveness of the patches to be broadly equivalent to that of the LHRH hormone therapy in terms of overall survival and remaining free of mets. Breast gland growth happened in twice as many patients on Estradiol (and Tamoxifen can't be used to suppress it), but hot flushes only occurred in half as many men.
The trial recommends that this becomes a standard of care as another option for hormone therapy (although that's not up to the trial - it will be up to NICE).
Summary here:
https://prostate.uroonco.uroweb.org/publication/prostate-cancer-efficacy-results-from-a-randomised-phase-iii-evaluation-of-transdermal-oestradiol-te2-versus-luteinising-hormone-releasing-hormone-agonists-lhrha-for-androgen-suppression-in-non-me/.
I doubt I can access the full paper - their previous paper was pay-walled.