Breast cancer hormone therapy serves as a treatment option for breast cancers that exhibit sensitivity to hormones. Various modalities of hormone therapy function by preventing hormones from binding to receptors on cancer cells. Others operate by reducing the body’s natural hormone production.
This type of therapy is exclusively employed for breast cancers that have been identified to possess receptors for the naturally occurring hormones estrogen or progesterone.
Following surgical procedures, hormone therapy for breast cancer is frequently administered to diminish the potential of cancer recurrence. Additionally, it can be used to shrink the cancer before surgery, potentially enabling a more conservative approach to breast tissue removal. Implementing hormone therapy prior to surgery also furnishes valuable insights to the medical team regarding the cancer’s responsiveness to this treatment.
In cases where cancer has metastasized to other body regions, hormone therapy for breast cancer holds the potential to aid in its management.
What is breast cancer?
Breast cancer is a prevalent form of cancer, ranking as the most common cancer globally and the primary cancer diagnosis in the United States. Presently, nearly 4 million women in the US alone receive a breast cancer diagnosis. While this prevalence doesn’t simplify the diagnosis process, it underscores the extensive research and dedication directed towards eradicating it. Encouragingly, these efforts yield progress, with survival rates rising due to improved and personalized treatments.
Similar to all cancers, breast cancer arises from DNA mutations that trigger unchecked cell growth. In this case, the target is breast tissue cells, and a single factor isn’t responsible for these mutations. A range of risk factors contribute, and accumulating these factors heightens the likelihood of breast cancer. Of note, being female is a significant risk factor, although men are not exempt, accounting for about 1 percent of cases.
Age also plays a role; as you age, the risk of breast cancer increases. Your personal or family history of breast cancer elevates your risk. Genetic factors, like BRCA1 and BRCA2 mutations, can predispose individuals to breast cancer. While not a certainty, the risk is notably higher with these mutations. Other factors include radiation exposure, having children at a later age, starting menopause later, and post-menopausal hormone usage.
Certain actions can mitigate your risk. Practicing self-breast awareness by monitoring any changes, especially for women aged 40 and above, is crucial. Annual mammograms are recommended for early detection, and your personal risk factors might prompt discussions about starting them earlier. Moderate alcohol consumption, maintaining physical activity, and maintaining a healthy weight can help lower the risk.
Addressing these factors in consultation with a healthcare provider can be beneficial. While post-menopausal hormones might be necessary, their role in breast cancer risk should be considered. Breastfeeding can reduce future breast cancer chances.
Be vigilant for potential signs, including breast lumps, changes in size or shape, alterations in breast skin, or nipple inversion. Skin changes, like peeling or redness, should not be ignored. Should these symptoms arise, consulting a doctor is imperative.
Suspecting breast cancer prompts the need for diagnostics. Physicians use physical exams, mammograms, ultrasounds, MRIs, and needle biopsies to establish the presence of cancer. If confirmed, you and your healthcare provider must discuss treatment options.
Crafting an Effective Approach to Breast Cancer Treatment
Breast cancer treatment necessitates a well-informed and strategic approach tailored to the situation’s specifics, including cancer size, stage, and type, hormone sensitivity, and more. The complexity of these factors demands a thorough evaluation before creating a treatment plan.
Surgery isn’t always the first step; medical therapy like endocrine therapy or chemotherapy might precede it. This approach can shrink breast tumors and evaluate treatment effectiveness, which is critical for post-surgery planning.
Surgical options range from lumpectomies to mastectomies, potentially involving lymph node removal. Post-surgery treatments, such as radiation and medical therapies, might be needed. When the disease has spread, surgery is usually avoided in favour of medical therapy.
Radiation utilizes energy beams to eliminate cancer cells and prevent recurrence, while chemotherapy deploys potent drugs to attack the cancer. Hormone-sensitive cancers can be treated with specialized drugs. Although these therapies entail side effects, your doctor will guide you through suitable options.
Immunotherapy is another avenue. By removing cancer cell defences, immunotherapy enables your body’s natural defence systems to target and eliminate the cancer.
The breast cancer treatment journey is challenging, but pain management and palliative care can aid the process. Facing breast cancer can feel overwhelming, but your loved ones offer invaluable support. Connecting with others who’ve experienced similar journeys through support groups can be comforting. Though a breast cancer diagnosis is daunting, advances in research and treatment have transformed it into a manageable condition. With evolving therapies and expert care, hope abounds
Why is hormone therapy for breast cancer done?
Hormone therapy exclusively targets breast cancers that respond to hormones. These hormone-sensitive breast cancers are propelled by the natural hormones estrogen and progesterone.
A breast cancer displaying sensitivity to estrogen is termed estrogen receptor-positive (ER-positive), while one responsive to progesterone is labelled progesterone receptor-positive (PR positive). Numerous breast cancers exhibit sensitivity to both hormones.
Laboratory tests ascertain whether cancer cells possess receptors for estrogen or progesterone. If at least 1% of cells contain these receptors, you become a potential candidate for hormone therapy. These tests enable your medical team to formulate an effective strategy for treating your breast cancer.
Hormone therapy for breast cancer offers several benefits:
- Preventing cancer recurrence.
- Reducing tumor size before surgery.
- Slowing or halting the growth of metastatic cancer.
- Lowering the risk of cancer emergence in other breast tissues.
Risks associated with Hormone Therapy for Breast Cancer
Hormone Replacement Therapy (HRT), also known as estrogen replacement therapy, menopausal hormone therapy, or post-menopausal hormone therapy, can serve as an effective remedy for menopausal symptoms. However, it’s crucial to recognize that certain forms of HRT can amplify the risk of breast cancer.
For individuals with a history of breast cancer, HRT can not only raise the likelihood of cancer recurrence but can also augment the initial risk. Consequently, doctors typically advise against the use of systemic HRT, which affects the entire body, for such individuals.
Additionally, HRT has been associated with cardiovascular risks, including heart disease, stroke, and blood clots. Nevertheless, these risks are subject to variation and contingent upon several factors, including the type of HRT, dosage, initiation age, and duration of usage.
Years ago, before the connection between HRT and breast cancer risk was established, many women utilized HRT for prolonged periods to alleviate menopausal symptoms and deter bone loss. After the revelation of the link between HRT and breast cancer risk in 2002, the utilization of HRT experienced a substantial decline.
Recent research, spanning a longer period, suggests that the connection between HRT and breast cancer risk is more intricate than initially believed, rendering the use of HRT a subject of controversy.
Medical guidelines underscore that for specific women, particularly those entering menopause at an early age, the advantages of HRT—encompassing enhanced quality of life and preservation of bone health—might outweigh the associated risks. Since the balance of risks and benefits varies for each woman, the optimal approach involves self-education and consultation with a medical professional to determine the suitability of HRT.
Breast Cancer Risk in Gender-Affirming HRT
Transgender women and non-binary individuals assigned male at birth (AMAB) who undertake estrogen as part of gender-affirming HRT encounter an escalated risk of breast cancer relative to cisgender men. After five years of HRT, trans women and AMAB non-binary individuals aged 40 and above, who possess an otherwise average risk, are advised to undergo annual mammograms.
The potential breast cancer risk associated with transgender men and non-binary individuals assigned female at birth (AFAB) who undergo testosterone as a component of gender-affirming HRT remains uncertain when compared to cisgender women.
Assessment of HRT Risks
The breast cancer risk linked to HRT varies based on the type of HRT and the individual’s breast cancer history.
Systemic Combination HRT and Breast Cancer Risk in Women without a Breast Cancer History
According to extensive findings from the Women’s Health Initiative studies, combination HRT heightens breast cancer risk, and this elevated risk persists for over a decade following HRT cessation.
Higher-dose combination HRT augments breast cancer risk more than its lower-dose counterparts. Moreover, combination HRT increases the likelihood of detecting cancer at an advanced stage due to its association with augmented breast density, which can impede mammogram accuracy.
The risk increase appears more pronounced with daily progesterone (continuous combination HRT) compared to less frequent progesterone (sequential or cyclical combination HRT). This risk augmentation pertains to both bioidentical and natural hormone products as well as synthetic hormones. Bioidentical hormones, sourced from plants, closely resemble endogenous hormones.
Conversely, synthetic hormones are chemically identical to those produced by the body. Importantly, numerous herbal and bioidentical HRT products fall outside the purview of the United States Food and Drug Administration’s regulations and testing procedures.
Systemic Estrogen-Only HRT and Breast Cancer Risk in Women without a Breast Cancer History
Estrogen-only HRT, according to the American Cancer Society, exhibits no association with elevated breast cancer risk. This assertion aligns with findings from the Women’s Health Initiative studies, which observed no heightened breast cancer risk among women using systemic estrogen-only HRT.
Nonetheless, in women with a uterus, systemic estrogen-only HRT amplifies the risk of endometrial cancer. Several studies also connect systemic estrogen-only HRT with an elevated risk of ovarian cancer. It’s worth noting that research diverges concerning the relationship between breast cancer risk and estrogen-only HRT, with some studies detecting a minor increase in risk while others do not.
Any Form of Systemic HRT and Breast Cancer Risk in Women with a Breast Cancer History
Due to concerns regarding the potential for systemic HRT to trigger hormone receptor-positive breast cancer recurrence, limited studies have examined HRT usage in women with a breast cancer history.
A 2021 analysis of four studies concluded that systemic HRT usage leads to a 46% higher recurrence risk compared to non-users. Current recommendations advise against any form of systemic HRT for women with a history of breast cancer.
Topical HRT and Breast Cancer Risk in Women without a Breast Cancer History
Research suggests that topical HRT, such as low-dose vaginal estrogen creams, tablets, and rings, does not escalate breast cancer risk since most hormones remain confined to the vaginal tissue.
Topical HRT and Breast Cancer Risk in Women with a Breast Cancer History
In 2016, the American Congress of Obstetricians and Gynecologists concluded that women previously diagnosed with breast cancer and experiencing distressing symptoms like painful intercourse might consider utilizing vaginal estrogen at the lowest effective dose when non-hormonal alternatives prove ineffective.
Common side effects of hormone therapy encompass:
- Fluctuations in body temperature (“hot flashes”)
- Excessive perspiration during the night (“night sweats”).
- Dryness or discomfort in the vaginal area
- Persistent tiredness.
- Erectile dysfunction in men diagnosed with breast cancer
Additionally, there are rarer but more severe potential side effects linked to hormone therapy:
For Tamoxifen:
- Formation of blood clots within veins
- Development of cataracts.
- Increased risk of endometrial or uterine cancer.
- Susceptibility to strokes.
For Aromatase inhibitors:
- Elevated risk of heart disease.
- Reduction in bone density (“thinning bones”).
Hormone Therapy for Breast Cancer Treatment
There are various methods of hormone therapy for breast cancer treatment.
Blocking Hormone Attachment to Cancer Cells
One approach to hormone therapy is to prevent hormones from binding to receptors on cancer cells. By preventing hormone access to cancer cells, their growth can decelerate, possibly leading to cell death.
Medications with this mechanism of action for breast cancer include:
- Tamoxifen: Usually taken daily in pill form, it’s often used to diminish the risk of cancer recurrence following treatment for early-stage breast cancer. The duration of use is typically 5 to 10 years. Tamoxifen is also employed in treating advanced cancer. It’s suitable for both post-menopausal and pre-menopausal women as well as men.
- Toremifene (Fareston): Administered as a daily pill, this is used to treat breast cancer that has metastasized to other parts of the body, specifically in post-menopausal women.
- Fulvestrant (Faslodex): Initially given via a shot every two weeks, followed by monthly shots, it’s utilized to treat breast cancer that has spread to other body regions in post-menopausal women.
Halting Estrogen Production
Aromatase inhibitors are medications that reduce estrogen levels in the body, depriving breast cancer cells of the hormones required for growth. These inhibitors are solely suitable for post-menopausal women, who must have experienced natural menopause or undergone induced menopause through medical intervention or ovarian removal. In men, aromatase inhibitors are often used in combination with other medications to enhance hormonal blockade. The three aromatase inhibitors used in breast cancer treatment are:
- Anastrozole (Arimidex).
- Exemestane (Aromasin).
- Letrozole (Femara).
These medications can lower the risk of cancer recurrence after early-stage breast cancer treatment and also address advanced breast cancer. They might be considered when tamoxifen is no longer effective or treatment is completed. These inhibitors are taken once daily and work by reducing estrogen production.
The duration of aromatase inhibitor therapy varies based on individual circumstances. The present research suggests a minimum of five years, with some individuals benefiting from seven to ten years. Your healthcare provider will collaborate with you to determine the optimal duration.
Ceasing Ovarian Function in Premenopausal Women
For premenopausal women who haven’t undergone natural menopause or who’ve experienced menopause due to cancer treatment, therapies can halt ovarian hormone production. Options include:
- Medications: Goserelin (Zoladex) or leuprolide (Lupron Depot).
- Surgery: Oophorectomy (ovary removal).
- Radiation Therapy: Targeting the ovaries.
These treatments may enable premenopausal women to access medications typically reserved for post-menopausal individuals.
Combining Targeted and Hormone Therapies
Hormone therapy is occasionally merged with targeted therapy, which targets specific chemicals in cancer cells. This synergy enhances the effectiveness of hormone therapy. Medications utilized in this combined approach encompass:
- Abemaciclib (Verzenio).
- Alpelisib (Piqray).
- Palbociclib (Ibrance).
- Ribociclib (Kisqali).
- Everolimus (Afinitor).
Hormone Therapy Journey for Breast Cancer
Throughout your hormone therapy journey for breast cancer, you will maintain regular follow-up visits with your oncologist. During these visits, your oncologist will inquire about any side effects encountered, many of which can be managed.
Research indicates that hormone therapy following surgery, radiation, or chemotherapy effectively lowers the risk of breast cancer recurrence in individuals with early-stage hormone-sensitive breast cancers. It also proves effective in mitigating the progression and growth of hormone-sensitive metastatic breast cancer.
Based on your circumstances, you might undergo monitoring tests to assess your medical status. These tests aid in monitoring cancer recurrence or progression during hormone therapy. The results provide your oncologist with insights into your treatment response, guiding potential adjustments to your treatment plan.
Concerns About Hormone Replacement Therapy and Risks
A major clinical trial released by the National Institutes of Health on July 9 has drawn attention to the risks associated with widely used hormone replacement therapy (HRT) involving estrogen and progesterone. Approximately 6 million postmenopausal American women rely on drugs like Prempro for symptom relief and health benefits.
The Women’s Health Initiative (WHI) study, a long-term randomized controlled medical trial, found that the combined HRT drugs led to increased breast cancer, heart attacks, strokes, and blood clots. Despite the individual risk being small, the overall population risk is considerable, outweighing the drugs’ limited benefits in decreasing hip fractures and colorectal cancer.
The WHI, initiated in 1991 to address postmenopausal women’s common health issues, included 67,000 women aged 50 to 79, focusing on the effects of HRT, dietary changes, and supplements. The study was to release its final results in 2006.
The findings prompted an early release due to unexpected cardiovascular risks and an unfavourable risk-benefit balance. Researchers halted the estrogen-progestin portion of the trial, advising those affected to discontinue the drugs. The study continues to evaluate estrogen-only treatments.
Experts expressed surprise at the findings’ release, although earlier studies hinted at the potential risks. The WHI director suggests women in this therapy consult with their doctors for reassessment, particularly those experiencing short-term symptoms.
Alternative options to HRT, such as lifestyle changes and non-HRT treatments, are discussed. However, experts caution against herbal remedies due to potential dangers and a lack of regulation. Despite uncertainties, experts emphasize that informed decision-making is crucial.
