How Does Menopausal Status Affect Breast Cancer?
If you’ve recently been diagnosed with hormone receptor-positive (HR+), HER2-negative (HER2-) breast cancer, you’re not alone. About 1 in 8 women will have breast cancer at some point in their lives. HR+ breast cancer is the most common type.
Because cancer is more likely with age, about 3 in 4 breast cancer cases happen after menopause. Menopause is a natural part of aging in which you don’t get periods anymore. If you go a year without a period, you could be diagnosed with menopause.
But you also could have breast cancer well before menopause. About 1 in 10 breast cancer cases in the U.S. happen before age 45. Premenopausal breast cancer is more common now than in the past. More women are getting breast cancer at younger ages for reasons that aren’t entirely clear.
The transition into menopause, or perimenopause, usually starts when you’re in your mid-40s or 50s. But it can start as early as your 30s if estrogen levels in your body start to swing up and down. Perimenopause usually lasts about four years, but it can go on even longer. Since there’s no simple test, you may be in perimenopause without even knowing it. While you won’t always know and can’t assume your menopausal status simply based on your age, it may affect your cancer journey in various ways.
“Menopausal status plays a significant role in breast cancer risk, tumor biology, diagnosis, and treatment decisions,” says Shari Goldfarb, MD, a breast medical oncologist and director of the Young Women with Breast Cancer program at Memorial Sloan Kettering Cancer Center in New York City.
Premenopausal vs. postmenopausal breast cancer features
Premenopausal women are more likely to have more aggressive, higher-grade, faster-growing tumors. The tumors are also more likely to be HER2-positive (HER2+) or triple-negative. On the other hand, postmenopausal breast cancers are more likely to be HR+ and slower growing.
Breast cancers after menopause often fall into a subtype of HR+ breast cancer called luminal A. This subtype usually has higher levels of a protein that makes them grow more slowly. These cancers also tend to respond better to hormone therapy.
If you aren’t sure what specific type of breast cancer you have or what it means given your menopausal status, ask your doctor to help you understand it. Ask whether you should consider more testing to learn more about your cancer and the best treatment options. Regardless of your menopausal status, it’s important to learn all you can about breast cancer, treatment options, and your prognosis.
Diagnosis, Staging, and Menopausal Status
Menopause itself doesn’t raise your chances of having breast cancer. But breast cancer does get more likely with age. You’re also more likely to have breast cancer if you go through menopause later in life. Women who enter menopause after age 55 get breast cancer more often. It’s also more likely if you got your period at an earlier age. That’s because your body has been making the hormone estrogen for a longer time. HR+ breast cancers have receptors on them that react to the hormones estrogen and progesterone.
Your menopausal status doesn’t usually change how your doctor diagnoses or stages your breast cancer. Breast cancer stage depends on the size of the tumor, whether it has spread to lymph nodes, and if it has moved beyond the breast tissue. Your doctor may also test for other biomarkers or genetic changes (mutations) that can influence how your breast cancer will grow or respond to treatment. While your menopausal status won’t change your breast cancer’s stage, type, or other test results, it may affect how your care team interprets them.
Breast cancers are often sent for genomic testing to help predict their risk of coming back. One such test, known as Oncotype DX Breast Recurrence Score, looks at how active certain genes in your cancer are. Those genes help predict how your early-stage breast cancer is likely to grow or spread in the future. Your menopausal status — along with other factors, including your age and health — will also influence your risk of breast cancer coming back.
How Menopausal Status Affects Breast Cancer Treatment
Your menopausal status can change your treatment options and what your oncologist recommends. It may also influence your other health risks, ability to tolerate certain medicines, or how aggressively you and your care team decide to treat your cancer.
When you’re premenopausal, your breast cancer treatment plan may depend on whether you plan to grow your family in the future. Your menopausal status can also affect the side effects you’re likely to experience from breast cancer treatment, as well as how you may manage any menopausal symptoms you may have now or in the future.
For instance, your menopausal status can affect how likely you are to benefit from chemotherapy. That’s especially true when your breast cancer has a medium risk of recurrence, as opposed to a low or high risk. Chemotherapy and hormone therapy are generally recommended when breast cancer is considered to have a high risk of returning, whether you are premenopausal or postmenopausal. If you’re premenopausal, you’re more likely to benefit from chemotherapy even when your breast cancer isn’t as likely to come back. Either way, your doctor will recommend hormone therapy.
“All women, regardless of their age [and menopausal status], are offered endocrine therapy, which is antiestrogen treatment, to reduce their breast cancer recurrence risk,” says Jasmine Sukumar, MD, a breast medical oncologist at the University of Texas MD Anderson Cancer Center in Houston, Texas. But your menopausal status can affect the type of endocrine therapy you may get.
Your doctor may recommend you take tamoxifen— a selective estrogen receptor modulator — for several years, whether you’re still getting periods or not. After your ovaries stop making estrogen, you may be more likely to take a different type of hormone therapy called an aromatase inhibitor. Aromatase inhibitors work by blocking an enzyme your body can use to make estrogen from other hormones.
Breast cancer treatment before menopause
Although your premenopausal status can influence your breast cancer, breast cancer treatment can influence menopause, too. If you haven’t gone through menopause yet, your breast cancer diagnosis and treatment can influence its timing. Hormone therapies used to treat HR+ breast cancers can bring on menopause earlier and speed up its progress.
If you need surgery to remove your ovaries, it will kick start menopause. Other treatments, including chemotherapy, may cause you to enter menopause temporarily. Temporary menopause can help protect your fertility. Because your hormone levels will be higher to begin with, the side effects of hormone therapy may feel more extreme.
“Premenopausal women who are made prematurely menopausal tend to have more intense menopausal symptoms of longer duration,” Goldfarb says.
Symptoms of menopause that may result from breast cancer treatment include:
- Hot flashes
- Night sweats
- Vaginal dryness
- Weight gain
- Mood changes
Breast cancer treatment in perimenopause
If you were already in perimenopause and experiencing menopausal symptoms before your diagnosis, breast cancer treatment (including hormone therapy) may worsen those symptoms.
“It can be challenging,” Sukumar says. “Sometimes people are already dealing with their menopause symptoms, and then breast cancer treatments can cause that, so it can be a double whammy. The important thing is that the patient and doctor work together to provide a good supportive care plan. We all want to make sure the quality of life is tolerable and treatment is manageable.”
Postmenopausal breast cancer treatment
If you’re in menopause or postmenopausal, you may be less likely to need chemotherapy. It depends on your cancer’s stage and recurrence risk. If you’re taking aromatase inhibitors to lower your estrogen levels, it may cause new symptoms of menopause or worsen symptoms.
“Postmenopausal women on aromatase inhibitors have [lower than normal] levels of estrogen, which may cause worsening menopausal symptoms,” Goldfarb says.
Low estrogen levels after menopause may come with other risks as you age, including low bone density and changes in how your heart works.
Hormone Replacement Therapy (HRT) for Menopause and Breast Cancer Treatment
If you were taking hormone replacement therapy (HRT) to manage perimenopause or menopause symptoms at the time of your diagnosis, your doctor will most likely tell you to stop.
That doesn’t mean you can’t treat your menopause symptoms. Ask about other alternatives, such as a low-dose antidepressant. Intravaginal moisturizers or topical estrogen can help with dryness. Other nonhormonal medications can help with hot flashes, insomnia, or other symptoms. Integrative medicine approaches may bring some relief.
“Things like acupuncture and yoga and mindfulness can help with hot flashes, fatigue, and some of the musculoskeletal symptoms,” Sukumar says. “Exercise is really important, too.”
Hormonal Changes and Breast Cancer: What’s Next?
If you aren’t sure what your menopausal status is or what it means for your breast cancer now or in the future, ask your care team about it. No matter what your current age, it’s important to know how your menopausal status may affect your cancer, its treatment, or its chance of coming back.
It’s also important to consider and talk with your doctor about how your menopausal status and future life goals may affect your treatment options, plan, and side effects. For example, if you haven’t gone through menopause, you should let your doctor know if you plan to have children in the future. Your oncologist can help you find ways to protect your ability to have kids through treatment. If your menopause status changes, it may also change the hormone therapy that’s recommended.
Ask your doctor if it would help to test your hormones to better understand your status and changes over time. At any stage, the key is to make sure you’re having honest and open conversations with your care team, Sukumar says. Ask about your treatment options and supportive care to ease any new symptoms as your hormones change.
“The menopause side effects can be one of the most challenging parts of the breast cancer journey, more than the chemotherapy or other aspects,” Sukumar says. By recognizing that and working closely with your doctor, you can find ways to deal with the condition.
