Estradiol Patches Show Promise as Prostate Cancer Treatment, Offering Alternative to Injections
Prostate cancer is the most common cancer in men, and when it progresses, treatments often extend beyond surgery or radiation. In locally advanced stages, or when there’s a risk of spread, hormone therapy is a cornerstone of treatment, aiming to suppress testosterone – a key fuel for many tumor cells. Traditionally, this has involved periodic injections or surgical removal of the testicles. However, newer, more selective drugs and administration methods are emerging, designed to control the cancer even as minimizing disruption to a patient’s quality of life.
A New Option: Estradiol Patches
A large clinical trial led by researchers at University College London (UCL) has indicated that estradiol patches are as effective in controlling locally advanced prostate cancer as the injections commonly used for hormone therapy. The study, published in The New England Journal of Medicine, found that patches delivering estradiol (a form of estrogen) through the skin were comparable to injections in preventing cancer spread and resulted in fewer side effects.
How Estradiol Patches Differ from Traditional Treatment
Current standard treatment involves injections of LHRH agonists (luteinizing hormone-releasing hormone agonists), requiring multiple hospital or doctor’s visits. Estradiol patches, however, can be self-administered at home, offering greater convenience. The side effects associated with LHRH agonists – including hot flashes, decreased bone density, and increased risk of cardiovascular issues like high cholesterol and blood sugar – were less common among men using the patches.
Study Details and Findings
The study involved 1,360 men with locally advanced, non-metastatic prostate cancer. Participants were randomly assigned to receive either estradiol patches or the standard LHRH agonist injections. After three or more years, researchers found similar outcomes in both groups: 87% of men in the estradiol patch group remained alive and cancer-free, compared to 86% in the injection group.
Side Effect Comparison
While both treatments have side effects, the nature and severity differed. Side effects from LHRH agonists stem from both decreased testosterone and estrogen levels (as testosterone converts to estrogen in men). Estradiol patches add estrogen back into the body, mitigating some of the side effects associated with low estrogen, such as hot flashes. 44% of men using patches reported hot flashes, compared to 89% in the injection group. However, breast tissue swelling (gynecomastia) was more common with the patches, affecting 85% of participants versus 42% with injections.
Impact on Bone Health
The study similarly indicated a potential benefit for bone health. Five years after the start of the trial, 2.8% of men who began with estradiol patches had experienced bone fractures, compared to 5.8% of those who started with injections.
Improved Quality of Life
Previous research suggests that overall quality of life is better for men receiving estradiol patches compared to injections. Cancer Research UK notes that hormone therapy is a common and effective treatment for prostate cancer, but can cause significant side effects.
Looking Ahead: Accessibility and Approval
Estradiol patches are currently not licensed in the UK specifically for prostate cancer treatment, meaning they are prescribed “off-label.” Researchers hope to secure wider availability, providing men with more treatment options. Approval processes vary by country, requiring manufacturers to apply for licensing extensions or new approvals from regulatory bodies like the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK and the Food and Drug Administration (FDA) in the United States.
“We hope to make these patches more widely available for the treatment of prostate cancer, so that men have the advantage of being able to choose their treatment,” says Professor Ruth Langley of UCL.
Worth a look