Menopausal Hormone Therapy After Breast Cancer

Post-menopausal hormone therapy (PHT), also called hormone replacement therapy (HRT), is sometimes used to help with menopause symptoms. This may not be safe for women who’ve had breast cancer, but there are other ways to relieve menopause symptoms without hormone therapy.

Can I take menopausal hormone therapy after breast cancer?

Doctors generally do not recommend post-menopausal hormone therapy (PHT) if a woman was previously treated for breast cancer, but there might be exceptions.

PHT is made up of the female hormone estrogen, sometimes along with progesterone. Some women use it to help reduce menopause symptoms. But there have been concerns about women using PHT if they’ve had breast cancer, because many breast cancers grow in response to higher estrogen levels.

A well-designed clinical trial (the HABITS study) found that breast cancer survivors taking PHT were much more likely to develop a new breast cancer or have their cancer come back after treatment, compared to women who were not taking these hormones.

Although doctors generally do not recommend PHT for breast cancer survivors, this depends on each woman’s situation. For example:

• Hormone receptor-positive (ER+ or PR+) cancer: The risk for women who had ER+ and/or PR+ breast cancer is clearly increased with PHT use, so it’s typically not recommended.
• Hormone receptor-negative (ER- and PR-) cancer: The risk for women whose breast cancer was ER- and PR- is not as clear. Some doctors might consider PHT as an option, especially if non-hormonal treatments are not helping with menopause symptoms.

Menopause symptoms after breast cancer

After treatment for breast cancer, many women have menopause symptoms such as hot flashes and vaginal dryness. This can happen naturally as you get older, but it can also be caused by some breast cancer treatments.

If you have not yet gone through menopause, you might still have menopause symptoms as a result of chemotherapy. Tamoxifen, aromatase inhibitors, and other hormone therapy medicines used to treat breast cancer can also cause these symptoms.

If you are past menopause, you might get menopause symptoms if you had to stop taking post-menopausal hormone therapy when you were diagnosed with breast cancer.

Relieving menopause symptoms without hormone therapy

If you are having trouble with menopause symptoms like hot flashes or vaginal dryness, talk to your healthcare team about ways other than PHT to help with specific symptoms. Non-hormonal medicines or other methods can often make a difference.

Non-hormonal medicines for hot flashes

Some medicines without hormone properties may help with hot flashes, including:

• Medicines that affect certain chemicals in the brain linked with hot flashes, such as fezolinetant (Veozah) or elinzanetant (Lynkuet)
• Certain antidepressants*, such as paroxetine (Brisdelle), venlafaxine (Effexor), or citalopram (Celexa)
• The nerve medicine gabapentin (Neurontin)
• The blood pressure medicine clonidine
• Oxybutynin, which is also used to treat overactive bladder

*If you take tamoxifen: Some antidepressants can interact with tamoxifen and could make it less effective. Ask your healthcare team about any possible interactions between tamoxifen and any other medicines you take.

Losing weight

Some women find losing weight helps with menopause symptoms such as hot flashes.

Diet and dietary supplements

Some women find it helpful to change the way they eat, such as eating smaller meals and avoiding triggers like spicy foods.

The effects of specific foods and dietary supplements on menopause symptoms are not clear. This doesn’t mean they won’t help, but the evidence supporting their use is limited.

• Phytoestrogens: These are estrogen-like substances found in certain plants, such as soy, red clover, and black cohosh. Some women take supplements containing these substances to try to help with menopause symptoms, but it’s not clear that this is safe if you’ve had hormone receptor-positive breast cancer.
• Soy foods vs. supplements: Eating soy foods seems to be safe for breast cancer survivors, although it’s not clear if it can help relieve menopause symptoms. Some dietary supplements, such as soy or isoflavone supplements, contain higher doses of phytoestrogens. Not enough is known about these supplements to know for sure if they are safe and if they work.

If you are thinking about taking one of these supplements, talk with your healthcare team first.

Exercise, relaxation techniques, and behavioral therapies

Some women find activities like exercise, relaxation techniques, and behavioral therapy help with menopause symptoms. There is only a limited amount of research to support this, but there is likely little harm in trying these activities.

Talk with your healthcare team before starting any exercise program after a breast cancer diagnosis.

Some research has suggested that acupuncture might be helpful in treating hot flashes, although not all studies have found this. It might be another option to discuss with your healthcare team.

Treatments for vaginal dryness

Vaginal dryness and discomfort can be bothersome menopause symptoms for some women.

Several non-hormonal treatments are available to help treat vaginal dryness, including vaginal moisturizers, lubricants, and gels. If these are not helpful, low-dose hormonal rings, tablets, capsules, or creams put directly into the vagina might be helpful.

Devices that use lasers or other forms of energy to rejuvenate vaginal tissue are now being studied as well, although it's not yet clear how helpful they might be. Always discuss the possible risks and benefits of these treatments with your healthcare team before deciding if one is right for you.