Coping with Menopause Caused by Breast Cancer Treatment

In 2011, over 50,000 of the more than 230,000 U.S. women diagnosed with breast cancer were under the age of 50. The average age of U.S. women at menopause is 51, and for premenopausal women, especially those who plan to have children, breast cancer treatment can have some worrying consequences.

Chemotherapy and Fertility Issues

Breast cancer is the most common female cancer, and it is often treated with chemotherapy. Chemo works by destroying rapidly-dividing cancer cells. The trouble is that some healthy cells—including those found in your hair follicles, the lining of the mouth and intestines, and the follicles in your ovaries—rapidly divide, too. It's the ovarian follicles that contain and release your eggs. Since chemotherapy does not distinguish between cancerous and non-cancerous cells, patients may end up with hair loss, painful mouth sores, nausea, decreased immunity, and even infertility due to chemo's destruction of the egg-containing ovarian follicles.

"During chemo a woman’s egg reserve decreases," says Sandy Kotiah, MD, medical oncologist at the Hoffberger Breast Center at Mercy Medical Center in Baltimore. Women are born with all the eggs they'll ever have, and with chemo, "She can lose about 10 years of egg reserve, which obviously impacts fertility."

Chemo can also trigger menopausal symptoms, such as hot flashes, vaginal dryness, sleep issues, and fuzzy thinking. This medical menopause (menopause brought on by medicines) may occur during and shortly after chemotherapy for breast cancer. If your menstrual cycle doesn't resume within a year of the end of treatment, menopause is likely permanent. (There's also surgical menopause, prompted by the removal of the ovaries in breast cancer patients with genes that put them at higher risk of ovarian cancer; this is permanent.)

Younger women who undergo chemotherapy for breast cancer typically experience disruptions to their menstrual cycle during the second or third round of chemotherapy, says Kotiah. "Menopause is rarely a sudden response to chemotherapy, but it can be difficult to predict how or when cancer treatment will affect the menstrual cycle."

"In my experience, if a patient’s period does not return within the year following treatment, they are probably in permanent menopause," Kotiah adds. "I have a 42-year-old patient whose cycles never returned, but I also have older patients who became regular again following chemo."

One Common Medication Also Plays a Role

Following chemotherapy, hormone therapy pills are often prescribed to prevent a recurrence of the cancer. Most hormone therapy medications either lower estrogen levels or prevent estrogen from acting, since this hormone can promote the growth of cancer cells. One if the most common hormone therapies is tamoxifen. "Tamoxifen blocks estrogen receptors on tumor cells and improves the survival rate for breast cancer," says Kotiah.

However, many women on tamoxifen complain of symptoms associated with menopause, including hot flashes, depression, vaginal dryness, hair thinning and nausea, Kotiah notes. Menstrual irregularities, including a lack of periods, are also possible. The menopausal symptoms aren't surprising, since declining levels of estrogen and progesterone are a major cause of menopause.

Tamoxifen can negatively affect fertility for another reason: It requires a long course (typically 10 years) of treatment, during which time women are generally discouraged from becoming pregnant, as the drug is associated with significant birth defects.

"The good news is, it’s still possible to ovulate and menstruate again when the medication ceases—even after a long break in cycles," Kotiah points out. "The bad news is the treatment time can potentially shorten the window to have children, depending on the age at diagnosis."

Some women choose to stop the medication to become pregnant. "Depending on the circumstances, many women elect to take a one to two year break from drug to allow for gestation [pregnancy] and breastfeeding," the doctor says.

Help for Menopausal Symptoms

Women coping with menopause symptoms are often prescribed hormonal therapy, usually consisting of estrogen or estrogen and progestin. But if you're one of the approximately 70 percent of patients with estrogen receptor-positive breast cancer (a specific type of breast cancer), hormone therapy can encourage the growth of cancer cells.

Luckily, there are other options: "Vitamin E gel capsules can be punctured and inserted, and water-based lubricants can really help with vaginal dryness. Wearing clothing in layers is a good way to deal with hot flashes and some women find acupuncture beneficial as well," says Kotiah. She also gives her patients Sexuality for the Woman with Cancer, a booklet produced by the American Cancer Society. "I make a point to speak with my patients on the topic of recapturing intimacy post breast cancer. Many are embarrassed and don’t bring it up, but having the information can make a big difference."

Options for Preserving Fertility

Fortunately, today recent advances offer young breast cancer patients more ways to potentially preserve their fertility. "Younger women who want to become pregnant should be referred to a fertility specialist immediately. Fertility specialists can concur with your oncologist [cancer specialist] to plan egg collection, fertilization, and embryo freezing before starting chemotherapy, depending on your stage and type of breast cancer. The process can take two to four weeks," Kotiah explains.

Modern techniques for freezing and storing unfertilized eggs have greatly improved pregnancy rates for breast cancer survivors. In the future, ovary harvesting may also be possible. "This is an evolving field with a lot of promise," Kotiah says.

Sandy Kotiah, MD, approved this article.


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