Hormone Therapy in Breast Cancer (2025 Guide): Role, Benefits, and What to Expect

Worldwide, breast cancer is one of the major causes of women’s deaths. In 2025, hormone therapy remains a very important treatment as it is the principal mode of treatment used in the control of hormone receptor-positive breast cancer, therefore, it contributes to the reduction of the risk of relapse and the extension of life. The treatment goes directly after the hormones that feed the development of certain breast cancers, so the cancer cells are either inhibited or eliminated completely.

By the year 2025, due to various new innovations in research and treatment strategies, hormone therapy is quite a bit more personalized, efficient, and patient-friendly than it used to be. We can delve into the mechanisms of hormone therapy, understand which patients it can help, and find out what future developments are anticipated in this field.

What is hormone (endocrine) therapy for breast cancer?

Hormone treatment or endocrine therapy is among the treatment methods that directly target mainly breast cancers caused by hormones- estrogen and/or progesterone.

The theme for Breast Cancer Awareness Month 2025—”Together We Thrive”—puts the focus on being one, understanding the power of the human spirit, and extending the hands of affection to others. It’s all about showing how much the community can achieve and letting people know that detecting the disease early is what helps save lives in the fight against breast cancer.

Hormone receptor-positive breast cancer

Cancer cells in the breast are examined for the presence of receptors: estrogen receptor (ER) and progesterone receptor (PR). If the cells have these receptors, the cancer is termed hormone receptor-positive (ER⁺ and/or PR⁺).
As these cancer cells could utilize those hormones for their proliferation, the process of inhibiting hormone activity or producing less hormone is turned into a treatment method.

How hormone therapy works

There are two fundamental strategies:

Blocking hormone receptors – molecules (like selective estrogen receptor modulators [SERMs] or selective estrogen receptor degraders [SERDs]) which do not permit estrogen to stimulate cancer growth.
Lowering hormone production/action – e.g., a lady after the menopause can use aromatase inhibitors to decrease the estrogen in the blood, and a girl before the menopause can have her ovarian function suppressed.

When is hormone therapy used in breast cancer?

Hormone therapy has several roles across the spectrum of breast cancer care.

Adjuvant (after primary treatment)

If it is an HR⁺ early-stage breast cancer, after surgery (± radiotherapy, ± chemotherapy), hormone therapy will be administered to reduce the risk of cancer returning.

Neoadjuvant (before surgery)

Some patients may be given hormone therapy before surgery to reduce the size of the tumour, particularly if the tumour is HR⁺ and the aim is to facilitate the surgery.

Treatment of advanced/metastatic disease

When breast cancer has spread (metastasised) or come back, hormone therapy can be a major component of systemic treatment for HR⁺ disease- most of the time, also together with other targeted therapies.

What are the main hormone-therapy options in 2025?

Hormone therapy remains one of the most effective treatments for hormone receptor–positive breast cancer. The main aim is to stop or reduce estrogen activity, thus not allowing it to promote the growth of cancer cells. The medicines that are given to a pre- or post-menopausal person are different; however, all the drugs work differently to finally achieve the same result – targeting the hormonal ‍‌‍‍‌pathways.

1. Selective Estrogen Receptor Modulators (SERMs)

These therapies work by attaching to estrogen receptors in breast tissue, preventing estrogen from binding and stimulating cancer growth. Interestingly, they can mimic estrogen’s beneficial effects on other parts of the body, such as the bones, helping maintain bone strength. SERMs are a long-established and trusted part of hormone therapy, especially for early-stage disease and prevention of recurrence.

2. Aromatase Inhibitors (AIs)

Aromatase inhibitors are designed to reduce the overall production of estrogen in the body. They block the enzyme that converts other hormones into estrogen, making them particularly effective in post-menopausal women. In some cases, they may also be combined with ovarian suppression strategies in pre-menopausal women to enhance treatment response.

3. Ovarian Suppression with Hormone Therapy

In pre-menopausal women, the ovaries are the main source of estrogen. Ovarian suppression involves temporarily or permanently stopping the ovaries from producing estrogen — through medication, surgery, or radiation — allowing hormone therapy to work more effectively. This approach is now a cornerstone for managing hormone receptor–positive breast cancer in younger women.

4. Selective Estrogen Receptor Degraders (SERDs)

Besides‍‌‍‍‌ that, these first-of-their-kind treatments are designed to inhibit the effect of estrogen and also facilitate the breakdown or removal of estrogen receptors from the cancer cells. As a result, SERDs are a future alternative in 2025 with a handful of next-generation oral drugs that are bright repigments in the condition of the loss of efficacy of normal hormone therapy. In addition, they are considered for the treatment of tumors that become resistant because of certain gene ‍‌‍‍‌mutations.

5. Resistance-Targeted and Combination Therapies

Sometimes‍‌‍‍‌ the cancer cells in some patients have the ability to change and thus become resistant to hormone therapy. For these cases, different combination strategies are now implemented, which include hormone therapy along with targeted agents that block the cancer cell growth pathways. As one of the most significant advances in 2025, this precision-based approach is a source of great excitement, as it provides patients with advanced-stage cancer increased control and improved treatment results over a longer period of ‍‌‍‍‌time.

What’s new in 2025? Key developments & guideline updates

2025‍‌‍‍‌ is seeing a major change in the method of hormone treatment in breast cancer; these are the main points:

Guideline updates

The National Comprehensive Cancer Network (NCCN) updated its recommendations (Version 4.2025) to reflect changes in the sequence and use of endocrine therapy in a more flexible manner.
The European Society for Medical Oncology (ESMO) and other scientific communities have published the evidence that supports the extension of adjuvant endocrine therapy for more than five ‍‌‍‍‌years.

Extended duration of therapy

Initially, hormone therapy for early HR⁺ disease was limited to 5 years. Now, data indicate that a benefit of 7-10 years (or even longer) in a certain subgroup of patients can considerably lower the risk of recurrence.
In particular, a 2025 study revealed that a majority of patients in real life continue treatment beyond 5 years.

Resistance and precision medicine

One of the biggest problems: HR⁺ breast cancers can become resistant to hormone therapy due to the occurrence of mutations (e.g., ESR1) or other factors.
The 2025 article explains that in the advanced/metastatic setting, the use of new hormone-targeting strategies (e.g., oral SERDs) is a way to get rid of ‍‌‍‍‌resistance.

Risk/benefit and hormone replacement therapy (HRT) context

Additionally, there is increasing discussion of the details of hormone therapy for menopause (HRT) in relation to the risk of breast cancer, which is very significant for patients with a history of breast cancer or those who are worried about a relapse.
For example, systemic HRT remains contraindicated in many women with prior HR⁺ breast cancer because of recurrence risk.

How clinicians decide on hormone therapy: personalised treatment

In 2025, deciding on hormone therapy is increasingly personalised. Here are key factors:

Tumour biology

Hormone receptor status (ER, PR) → only HR⁺ tumours are capable of responding to hormone therapy.
More biomarkers: HER2 status, genomic assays, ESR1 mutation status (mainly in advanced disease).

Menopausal status

The difference between premenopausal and postmenopausal status is what mainly determines the choice of a therapy: tamoxifen vs AI, ovarian suppression, duration, and side-effect profile.

Risk of recurrence and stage

The differences between early-stage and advanced, node-positive vs node-negative, size, grade, and other features of risk are how the factors influencing the decisions are ‍‌‍‍‌determined.
For‍‌‍‍‌ instance, those patients who are at a significantly higher risk of having a late recurrence could potentially take advantage of an extended endocrine therapy that goes beyond 5 years.

Duration of therapy

Although 5 years is still the norm in most cases, the doctor may recommend a high-risk patient to prolong the treatment up to 7-10 years (or even longer).

Monitoring & managing adherence

The problem is that several patients decide to discontinue their treatment prematurely due to side effects or because they find it too burdensome. Those who are on the treatment must be very diligent if any good result is to be expected.

Resistance and escalation

Once hormone therapy loses its effectiveness in advanced/metastatic HR⁺ disease, the patient can be advised to change the hormone therapy type, targeted therapies (like CDK4/6 inhibitors, etc) can be added, or the doctor may suggest other ‍‌‍‍‌treatments.

Benefits of hormone therapy

Greatly‍‌‍‍‌ lowers the risk of cancer coming back in HR⁺ breast cancer.
If used as a main treatment, patient survival is increased and the risk of cancer in the other breast is lowered.
More simpler to give (usually oral pills) than a lot of other systemic therapies (though side-effects are still present).
In most situations, hormone therapy can provide disease control for a long time and be less toxic (particularly in the early stage) than ‍‌‍‍‌chemotherapy.

Managing Side Effects, Adherence, and Long-Term Challenges of Hormone Therapy (2025 Update)

Even‍‌‍‍‌ if hormone therapy is still one of the most powerful means of treating hormone receptor–positive breast cancer, it is capable of causing a set of different physical, emotional, and delayed problems in the patient. The year 2025 sees the clinical focus changing in such a way that the main points now are side effect reduction, patient adherence support, as well as comprehension of late recurrences and resistance patterns, which, being very important, lead to better long-term outcomes and a higher quality of ‍‌‍‍‌life.

Side Effects

Side‍‌‍‍‌ effects of hormone therapy vary depending on the type of treatment a patient receives and whether the patient is menopausal. Commonly, people go through hot flashes, night sweats, and mood changes, which are the effects of hormonal shifts. Some medicines can also raise the risk of losing bone density thus causing joint pain or muscle stiffness, whereas others may result in sexual or cognitive changes gradually.

Besides that, drugs that block estrogen receptors may occasionally cause changes in the uterus or the formation of blood clots as a result of partial estrogen activity in certain tissues. Contrarily, treatments that reduce estrogen production can make a patient susceptible to bone thinning and fractures. Hence, regular check-ups and the initiation of bone-strengthening activities at an early stage comprise the main elements of the current ‍‌‍‍‌treatment.

Adherence Challenges

Usually,‍‌‍‍‌ hormone therapy is given as a treatment for a period of five years or more, and, as a result, many people find it hard to keep it up for such a long time. It is quite common that side effects, emotional exhaustion, or the inconvenience of taking a daily pill can be the reasons for a dose being missed or a therapy being stopped at an early stage, thus the treatment being less effective. In 2025, cancer care professionals are putting more and more emphasis on the use of counseling, digital monitoring tools, and patient support programs as means of treatment adherence and retention of therapy ‍‌‍‍‌benefits.

Late Recurrences

One‍‌‍‍‌ of the facts of life is that breast cancer with hormone receptor–positive can relapse after a very long time, i.e., sometimes more than ten years from the initial diagnosis, even after five years of hormone therapy. This long-term risk is the main reason why the extended endocrine therapy (7–10 years or even longer in some cases) alternative is still debated in the new guidelines. Follow-up appointments that are planned regularly and being watchful for slight symptoms are also two other necessary components of the care given to ‍‌‍‍‌survivors.

Resistance and Treatment Adaptation

Over time, certain cancers can become resistant to hormone therapy caused by changes in their genes or adaptive mechanisms of the tumor. In such cases, doctors can change to another type of hormone therapy or use a combination of endocrine therapy and new targeted drugs to get the hormone therapy response back again. In 2025, precision medicine, which is directed by genomic testing and tumor monitoring, is becoming more and more significant to be able to ‍‌‍‍‌resist.

Hormone Therapy vs. Hormone Replacement Therapy (HRT)

One‍‌‍‍‌ of the main differences that should be kept in mind is that cancer hormone therapy is different from hormone replacement therapy. Cancer hormone therapy blocks or lowers hormones that cause tumors to grow, while HRT supplies the hormones that the body lacks. People who have had hormone receptor–positive breast cancer are usually advised not to take systemic HRT as it may cause the cancer to return, however, studies are still ongoing to find safer ‍‌‍‍‌options.

Practical considerations for patients & caregivers

Questions to Ask Your Oncologist

If‍‌‍‍‌ either you or someone dear to you is going to undergo hormone therapy as a treatment for breast cancer, then it would be vital to keep yourself updated and involved in every decision. Below are some of the useful inquiries that can facilitate your ‍‌‍‍‌conversations:

Is my tumor hormone receptor–positive (ER/PR status)?
Is hormone therapy recommended for my specific stage and risk level?
How long is the treatment expected to last?
What kind of side effects should I be aware of?
How will we monitor progress and watch for signs of recurrence?
How does my menopausal status influence treatment options?
What lifestyle choices can support the success of my therapy, such as nutrition, exercise, and bone health?

Lifestyle & Supportive Care Tips

In‍‌‍‍‌ many cases, management of hormone therapy will depend on holistic care, which is a major strategy of everyday life during treatment:
Put bone health at the top of your list: Eat the necessary amount of calcium and vitamin D, keep your body in good shape through weight-bearing exercises, and have your bone density checked regularly.
Side effect control at the earliest stage: Take care of hot flashes, mood changes, lack of energy, or pain in the joints quickly in order to increase your comfort level and treatment adherence.
Never lose your faith: It is very hard to stay in therapy for a long time, but if you are diligent, then the results will be really positive.
Open communication: Inform your medical team about any new symptoms or the worsening of the existing ones. Even little changes can make a big ‍‌‍‍‌difference.

What About Hormone Replacement Therapy (HRT)?

Usually,‍‌‍‍‌ a hormone replacement therapy that is generally used to relieve the symptoms of menopause is not allowed to be used by patients who have had a hormone receptor-positive breast cancer, as it may increase the risk of cancer recurrence.
As a result, the non-hormonal drugs and adherence to lifestyle changes are the primary means of alleviating the menopausal symptoms. There are also situations when the application of certain local or topical products may be regarded as very safe and comfortable if a doctor guides ‍‌‍‍‌you.

Real-world data & patient trends in 2025

Studies‍‌‍‍‌ done recently reveal the changes in hormone therapy implementation in 2025:

Expanded duration of treatment: It is reported that almost 50% of patients with breast cancer continue hormone therapy beyond five years, which shows a trend of prolonged therapy for protection over the years.
Better long-term results: Evidence suggests that regular hormone therapy can lower the risk of cancer occurring in the other breast and can also increase the survival rate of hormone receptor–positive (HR⁺) patients.
The use of precision medicine: For heavily impacted cases, a better understanding of the tumor genetics and molecular changes is leading doctors to be more accurate in choosing the treatment, which in turn results in patients’ improvement through the adoption of personalized care ‍‌‍‍‌strategies.

Future Directions & What to Watch For in 2025

The‍‌‍‍‌ future of breast cancer hormone therapy is being influenced by the ongoing research trends in hormone therapy for breast cancer. Some of them are:

Personalized duration of treatment: The specialists are determining the duration of hormone therapy more precisely — in numerous cases, 7–10+ years of treatment might be necessary, the exact length being dependent on the risk of cancer recurrence.
Innovative hormone-blocking strategies: The trial results of oral SERDs and hormone receptor degraders have been very encouraging, giving new hope to patients who, in general, become resistant to previous therapies.
Precision medicine in action: The integration of genomic biomarkers like ESR1 and PIK3CA mutations, along with ctDNA tracking, is helping doctors to deliver the treatment in a more precise way.
Improving quality of life: The research is deeply involved in efforts to reduce the side effects, make adherence easier, and guarantee the long-term well-being of the survivors.
Global accessibility: Advanced hormone therapy is becoming a subject of interest not only in rich countries but also in low- and middle-income countries, where it is difficult to access.
Holistic survivorship research: Scientists are studying how hormone therapy impacts fertility, bone health, and cardiovascular wellness over the long term.

Summary & Key Takeaways

Hormone‍‌‍‍‌ (endocrine) therapy continues to be a major component of the treatment of hormone receptor–positive (HR⁺) breast cancer. The aim is to block or interfere with the activity of estrogen and progesterone.
Such a treatment is implemented in all stages — early (adjuvant/neoadjuvant) as well as advanced (metastatic) disease.
The main points of 2025 include: extended treatment durations beyond five years, becoming increasingly resistant to treatment, new hormone-targeting agents, and updated NCCN (v4.2025) guidelines.
Personalized medicine: choices of treatment are made depending on tumor biology, menopausal status, recurrence risk, and patient preferences.
Side-effects management and adherence to the treatment regimen are of utmost importance — taking care of symptoms in a proactive way and making lifestyle adjustments really improve the results.
If at all, hormone replacement therapy (HRT) should be administered very cautiously — particularly in patients with prior HR⁺ breast cancer, where non-hormonal symptom management is a safer option.
Precision medicine is the ultimate goal: biomarker-guided therapy, improved side-effect management, and endocrine treatments accessible to everyone ‍‌‍‍‌worldwide.