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- Tai chi: A gentle way to fight stress
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- Bone metastasis
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- Support groups: Make connections, get help
- Palliative care: Symptom relief during illness
Prevention (5)
- Genetic testing for breast cancer: Psychological and social impact
- Prophylactic mastectomy: Surgery to reduce breast cancer risk
- Breast cancer prevention: How to reduce your risk
- see all in Prevention
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- Obesity
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- Breast lump: Early evaluation is essential
Tests and diagnosis (8)
- Breast cancer staging
- Biopsy: Types of biopsy procedures used to diagnose cancer
- Breast cancer types: What your type means
- see all in Tests and diagnosis
Treatments and drugs (14)
- Radiation therapy
- Breast augmentation
- Chemotherapy
- see all in Treatments and drugs
continued:
Breast cancer chemoprevention: Medicines that reduce breast cancer risk
Aromatase inhibitors
Aromatase inhibitors are commonly used to treat breast cancer that's hormone-receptor positive in postmenopausal women. These drugs aren't widely used for breast cancer chemoprevention, but they may be an option for some women. Aromatase inhibitors are the subject of much ongoing research.
How they work
Aromatase inhibitors are a class of medicines that reduce the amount of estrogen in your body, depriving breast cancer cells of the fuel they need to grow and thrive. Three aromatase inhibitors are currently used in the treatment of postmenopausal women with breast cancer: anastrozole (Arimidex), exemestane (Aromasin) and letrozole (Femara). These medications are used after breast cancer surgery to prevent breast cancer from returning (recurring) in postmenopausal women with estrogen- or progesterone-responsive tumors.
Who it's for
Aromatase inhibitors have been studied and shown to be effective in postmenopausal women to treat breast cancer and to prevent breast cancer recurrence. Aromatase inhibitors are not intended for preventing breast cancer recurrence in women who still have menstrual cycles.
Aromatase inhibitors are being studied to see if they may reduce the risk of breast cancer in high-risk women, such as those with a family history of breast cancer or a history of precancerous breast lesions. Studies have shown promise in these high-risk women. Based on these results, some women and their doctors may choose to use aromatase inhibitors to reduce the risk of breast cancer, though these drugs aren't approved for this use.
Common side effects
Common side effects of aromatase inhibitors include:
- Hot flashes
- Vaginal dryness
- Joint and muscle pain
- Headache
- Fatigue
Risks
Aromatase inhibitors raise the risk of:
- Broken bones (fractures)
- Osteoporosis
Because aromatase inhibitors are a newer class of medications, not much is yet known about long-term health risks, such as heart disease. As more results from research studies become available, doctors will have a better idea of the long-term health implications for these drugs and their effectiveness in breast cancer chemoprevention.
Other areas of research
Aspirin and other pain relievers
Several studies have looked into whether common over-the-counter painkillers, such as aspirin, ibuprofen (Advil, Motrin, others) and naproxen sodium (Aleve), may reduce the risk of breast cancer.
Study results are mixed. Some research has found that women who had breast cancer and who regularly take these pain relievers have a slightly decreased risk of breast cancer recurrence. But other studies haven't shown a significant association between breast cancer risk and these pain relievers.
It remains unknown whether aspirin and other pain relievers help protect against breast cancer, and if so, exactly how they do so. Because some pain relievers, such as celecoxib (Celebrex) and naproxen sodium (Aleve), may increase the risk of heart attack and stroke, talk with your doctor to weigh the potential benefits versus the risks of taking these medications in your situation.
Vitamin D
Studies are examining whether vitamin D may have some role in preventing breast cancer and breast cancer recurrence. Preliminary research has shown that vitamin D may have anticancer properties. Early studies in breast cancer survivors linked lower than normal vitamin D levels to an increased risk of cancer recurrence. More studies are needed to understand the action and potential benefits of vitamin D.
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- American Society of Clinical Oncology clinical practice guideline update on the use of pharmacologic interventions including tamoxifen, raloxifene and aromatase inhibition for breast cancer risk reduction. American Society of Clinical Oncology. http://jco.ascopubs.org/cgi/content/full/27/19/3235. Accessed Dec. 28, 2010.
- Wickerham DL. Breast cancer chemoprevention: Progress and controversy. Surgical Oncology Clinics of North America. 2010;19:463.
- Medicines to reduce breast cancer risk. American Cancer Society. http://www.cancer.org/acs/groups/cid/documents/webcontent/002585-pdf.pdf. Accessed Dec. 29, 2010.
- Harris RE, et al. Breast cancer and nonsteroidal anti-inflammatory drugs: Prospective results from the Women's Health Initiative. Cancer Research. 2003;63:6096.
- Terry MB, et al. Association of frequency and duration of aspirin use and hormone receptor status with breast cancer risk. Journal of the American Medical Association. 2004;291:2433.
- Agrawal A, et al. NSAIDs and breast cancer: A possible prevention and treatment strategy. International Journal of Clinical Practice. 2008;62:444.
- Pruthi S (expert opinion). Mayo Clinic, Rochester, Minn. Oct. 18, 2011.
- Vogel VG, et al. Effects of tamoxifen vs raloxifene on the risk of developing invasive breast cancer and other disease outcomes: The NSABP study of tamoxifen and raloxifene (STAR) P-2 trial. JAMA. 2006;295:2727.
- Giovannucci E, et al. Role of vitamin and mineral supplementation and aspirin use in cancer survivors. Journal of Clinical Oncology. 2010;28:4081.
- Goss PE, et al. Exemestane for breast-cancer prevention in postmenopausal women. The New England Journal of Medicine. 2011;25:2381.


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