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Study: Aromasin Shown to Reduce Breast Cancer Risk


A recent study finds that Aromasin may reduce the risk of breast cancer in women at high risk of developing the disease. Aromasin has been used by physician for a decade to treat advanced breast cancer in some women. In the study, Aromasin decreased breast cancer risk by nearly two thirds. However, more long-term follow up is needed to confirm the findings.

Aromasin (generic name, exemestane) was FDA-approved in 1999 to treat advanced breast cancer in post-menopausal women. Aromasin works by binding to the body's aromastase enzyme, an enzyme responsible for producing the hormone, estrogen. Many breast cancer cells depend on estrogen to grow and multiply quickly. Once aromasin has binded to the aromastase enzyme, estrogen cannot be produced by the enzyme. This lack of estrogen "starves" cancer cells, preventing them from growing. Aromasin is usually taken orally in pill form.

To conduct the current study, Dr. Paul Goss, Director of Breast Cancer Research at Massachusetts General Hospital, and colleagues studied over 4500 women. The researchers saw a 65 percent decrease in breast cancer risk among the women who took Aromasin, compared to women who took a placebo, or inactive pill. Specifically, there were 11 invasive breast cancer cases among women who took Aromasin, compared to 32 among women who took the placebo.

Possible side effects of Aromasin include:

  • Hot flashes
  • Nausea
  • Fatigue
  • Increased sweating
  • Increased appetite

Women in the study also had a slight increased risk of osteopenia, or a decrease in bone density.

The study was presented at the 2011 annual meeting of the American Society of Clinical Oncology, www.asco.org