Breast cancer prevention drugs have improved in the last twenty years; however, many women who could benefit from taking these drugs do not take them according to Harvard University’s, Harvard Women’s Health Watch article in the January 2014 issue.
Women at high risk of getting breast cancer surprisingly do not take the medication, as well.
According to Dr. Paul Goss, director of breast cancer research at the Massachusetts General Hospital Cancer Center,
"These drugs have been shown to prevent the occurrence of invasive and pre-invasive breast cancers. It isn't just cancer that's prevented. It's precancer and abnormal mammograms. That leads to fewer biopsies."
Medication, like exemestane (Aromasin), raloxifene (Evista), and tamoxifen (Nolvadex) are capable of reducing the chance of developing breast cancer for numerous women at high risk of developing breast cancer.
Doctors are hesitant in prescribing these drugs and many women are reluctant to take these drugs due to the side effects, which comprise of increased risk of uterine cancer and blood clots. However, these medications have a long history of effectiveness and safety according to researchers who studied the usage of these drugs in women. Dr. Goss explains:
"Tens of thousands of women have taken these medications worldwide, so the side effect profiles are extremely well defined."
The three drugs work on estrogen receptor positive breast cancer, the most common type of cancer. For postmenopausal women breast cancer prevention using two selective estrogen receptor modulators (SERMs)—tamoxifen, raloxifene, and the aromatase inhibitor exemestane are recommended according to the Harvard publication.
Women who are at very high risk for breast cancer should be considered for preventive drugs:
- a personal history of breast cancer
- a history of radiation to the chest from another cancer (such as Hodgkin's disease or non-Hodgkin's lymphoma)
- a past breast biopsy that showed atypical ductal hyperplasia or lobular carcinoma in situ—precancerous conditions that increase the risk for invasive breast cancer
- an inherited BRCA gene mutation
The report also suggests that it is harder to identify women as candidates who have a family history of breast cancer. Expert groups recommend SERMs or aromatase inhibitors for all women at high risk for breast cancer based on their score on the National Cancer Institute Breast Cancer Risk Assessment Tool.
Calculate your risk by visiting http://www.cancer.gov/bcrisktool. However, the threshold score differs by organization:
- The American Society of Clinical Oncology defines high risk as a score of at least 1.66%.
- The U.S. Preventive Services Task Force considers you at high risk if your five-year breast cancer risk score is 3% or higher.
Women who are at high risk of getting uterine cancer and blood clots probably should not take these drugs. It is also important to consider how the quality of your life may change while taking this medication. Taking this medication may cause women to feel uncomfortable menopause-like symptoms, such as vaginal dryness and hot flashes (since the drugs can block the effects of estrogen). In addition, aromatase inhibitors can weaken bones.
It is imperative for women to consult their physician and discuss whether breast cancer prevention drugs are safe and reasonable to take.