Vanderbilt University Assistant Professor Liana Castel, PhD, knows that aromatase inhibitors (drugs like Arimidex, Femara, and Aromasin) can help stop hormone-positive breast cancer from coming back in patients who have gone through menopause. But she also knows that side effects like joint pain have led some women to stop taking the drugs. Castel’s research, funded by the American Cancer Society, attempts to better understand how joint pain affects women and develop strategies to help them continue taking the drugs.

Aromatase inhibitors fight cancer by lowering the level of estrogen, which fuels breast cancer growth. The drugs only work in women whose ovaries have stopped making estrogen (like after menopause) because they can’t stop the ovaries of pre-menopausal women from making it. Using these drugs, often for 5 years or more, has been shown to reduce the risk of the cancer coming back.

Loss of estrogen has been linked to symptoms including joint pain or stiffness. Since these drugs are relatively new, it is not yet known how common these symptoms are, or how likely they are to get better or go away over the 5 or more years of therapy. Often women can find help by switching to another drug like tamoxifen , but some women may simply give up. It’s also not known how much joint pain could be expected from estrogen loss in post-menopausal women who don’t have cancer.

Castel’s study is designed to answer these questions by following a group of women over time, starting from before they start taking aromatase inhibitors. The researchers will look into pain, quality of life, why women stop taking the drugs early, and whether different treatments show promise for easing joint pain. These treatments may include prescription medicine, over-the-counter medicine, supplements, exercise, massage, or better sleep at night. Women who have gone through menopause, whether or not they have breast cancer, are needed for the study, which is currently enrolling volunteers. Information on the study is available online at breastcancersurvivorstudy.com, or by calling 1-800-811-8480.

A Personal Connection

Castel was inspired to begin researching breast cancer by her grandmother and mother, who were both diagnosed with the disease. Her grandmother enrolled in the original tamoxifen trial in 1971, and Castel says the drug saved her life. Castel’s mother, herself a health services researcher, is a breast cancer survivor who switched from aromatase inhibitors to tamoxifen after experiencing joint pain. Castel said, “Mom has been guiding me in things I want to look at. She has a perspective from the point of view of a survivor as well as a researcher.”

The career development award Castel received from the American Cancer Society will support her research in patient-reported outcomes and treatment adherence among early-stage breast cancer patients taking aromatase inhibitors as adjuvant therapy. Castel, a professor at Vanderbilt University in Nashville, Tennessee, also does research in other areas of cancer survivorship and health outcomes issues, clinical effectiveness of therapies, evidence-based medicine, patient preferences, racial disparities, and other outcomes in cancer and chronic diseases.

However, Castel has not limited her interest in breast cancer to the lab. She has participated in the local Nashville Making Strides Against Breast Cancer event, which raises money for research like hers. At a kick-off breakfast at one event she spoke about the relationship between aromatase inhibitors and joint pain, and the dangers for patients who skip doses. She quoted former Surgeon General C. Everett Koop, who said, “Drugs don’t work in patients who don’t take them.”

Note: This information was originally published in March 2013 Breast Cancer Update newsletter.