CATEGORY: MEN’S HEALTH
Estrogen delivered through skin patches held locally advanced prostate cancer as well as the standard hormone injections did, in a randomized UK trial of 1,360 men. Three years in, 87.1% of patch users and 85.9% of injection users were alive with no sign the cancer had spread. The share of men troubled by hot flashes fell by half on the patches, from 89% to 44%.1
Switching Off Testosterone by Another Road
Most prostate cancers grow on testosterone, so a mainstay of treatment is hormone therapy, medicine that shuts the hormone off. The standard version is an injection of an LHRH agonist, given every one to three months. It silences the gland in the brain that tells the testes to make testosterone. The trial tested a very different route to the same destination: patches of estradiol, the main form of estrogen, worn on the skin, typically four at a time and swapped for fresh ones twice a week. They quiet the same brain signal. Both roads got there. By one year, 85% of the men in each group had testosterone suppressed to the very low level the treatment aims for.1
Fifteen Years of Enrolling for One Direct Comparison
Between 2007 and 2022, researchers at 75 UK hospitals signed up 1,360 men at a median age of 72, all with cancer that had grown locally or reached nearby lymph nodes without travelling further. Allocation to patches or injections was drawn, not chosen. A patch on the skin cannot be disguised as an injection, so everyone knew which treatment they were on; the outcomes being counted, cancer spread and death, leave little room for wishful reading. The question was deliberately conservative. Not whether patches beat injections, but whether they were at least as good, inside a margin fixed in advance. They were. At three years the figures were 87.1% and 85.9% alive without distant spread, and at five years 81.1% and 79.2% still living, with no sign the patches gave anything away.1
The Old Estrogen Pill, Retried Through the Skin
Estrogen is not a new idea here. Pills of it controlled prostate cancer back in the 1960s and were then abandoned, because estrogen swallowed by mouth passes first through the liver, where it stirs up clotting factors. Strokes, clots and heart deaths followed. The researchers’ bet, stated from the program’s start, was that skin delivery would sidestep exactly that. A patch, the same kind of adhesive square used for nicotine replacement or menopause hormones, feeds estradiol straight into the bloodstream and skips the liver’s first pass. Long-term safety results from the same trial program bore the bet out, finding cardiovascular event rates similar in the two groups.2
Half the Hot Flashes, Fewer Fractures, More Breast Tenderness
Side effects are where the two treatments parted company. Hot flashes, often the most wearing part of hormone therapy, reached 44% of patch users versus 89% of injection users, and the severe kind 8% versus 37%. Estrogen protects bone while standard hormone therapy thins it, and fractures over five years followed suit: 2.8% with patches versus 5.8% with injections. The chest is where the trade runs the other way. Gynecomastia, meaning swelling or tenderness of breast tissue, affected 85% of patch users against 42% on injections, though it was usually mild. Severe adverse events overall came in slightly lower with patches, 16% versus 19%. One practical note: the patches go on at home rather than at appointments, but they are not yet licensed for prostate cancer, so prescribing is off-label while the trial team pursues approval.1
Key Takeaways
- Estrogen skin patches matched standard hormone injections in 1,360 men with locally advanced prostate cancer: 87.1% versus 85.9% alive without cancer spread at three years, with five-year survival also similar.
- Patch users had far fewer hot flashes (44% versus 89%) and fewer fractures over five years (2.8% versus 5.8%), and much more breast swelling or tenderness (85% versus 42%).
- The heart harm that ended estrogen pills for prostate cancer last century did not appear with skin delivery; long-term results from the same program found similar cardiovascular event rates in both groups.
- Estradiol patches carry no license for prostate cancer yet, and are available only by off-label prescription while approval is sought.
References
- Langley RE, Gilbert DC, Mangar S, et al. Transdermal Estradiol Patches in Locally Advanced Prostate Cancer. New England Journal of Medicine. 2026;394(16):1595–1607. link
- Langley RE, Gilbert DC, Duong T, et al. Transdermal oestradiol for androgen suppression in prostate cancer: long-term cardiovascular outcomes from the randomised Prostate Adenocarcinoma Transcutaneous Hormone (PATCH) trial programme. The Lancet. 2021;397(10274):581–591. link