20 Years of Learning Breast Cancer Causes and Prevention

Kevin Fox MD, is the Mariann T. and Robert J. MacDonald Professor of Medicine and medical director of the Rena Rowan Breast Center at Penn’s Abramson Cancer Center. He treats all aspects of early stage and advanced stage breast cancer researches adjuvant therapy of breast cancer.

Every aspect of breast cancer prevention, diagnosis and treatment has seen meaningful changes in the last 20 years. In some areas of breast cancer research and treatment, the advances have been subtle; in other cases, they have been profound.

Learning what causes breast cancer

In just 20 years, we’ve come to understand there are many factors that can contribute to a woman’s risk of getting breast cancer.

In 1994, we learned that certain women have mutations in one of two genes — either BRCA1 or BRCA2 — and that these women were at a higher risk of developing breast and ovarian cancer during their lifetimes.

In 2002, we learned that women who take hormone replacement therapy (HRT) in the form of premarin and progesterone have an increased risk of breast cancer versus those who do not take HRT. The risk is not great, and women who took premarin without progesterone didn’t have such a risk, but as a result, millions of women stopped taking HRT.

Advances in breast cancer prevention

Mammograms

The mammogram remains the most important screening device in the detection of breast cancer and it probably saves thousands of lives every year.

Several years ago, the digital mammogram became the standard in most hospitals and breast centers. The digital mammogram experience isn’t much different for the patient, but these digital images are more accurate than older, film screen mammograms, particularly for younger women or women with very dense breasts.

Today, the breast imaging technology at the Ruth and Raymond Perelman Center for Advanced Medicine includes digital breast tomosynthesis, or DBT, to perform three-dimensional mammography for breast cancer screening and diagnosis.

The DBT system employs a digital X-ray that records a series of low-dose, high-resolution images of the breast while traversing a small (15 degree) arc around the compressed breast. The advantages of DBT include fewer false-positives and false-negatives associated with traditional mammography.

Preventative drug therapy

By 1998 we learned that a woman’s risk of developing breast cancer can be cut by 50 percent by taking the drug tamoxifen for five years. Several years later, researchers found that the drug raloxifene could accomplish the same thing, but only in postmenopausal women. More recently, the drug exemestane has been shown to reduce breast cancer risk as well, but again, only in postmenopausal women.

These drugs, however, have not gained widespread use in most women because of unpleasant side effects.

Learn more about breast cancer treatment at the Abramson Cancer Center in Philadelphia.

Watch conference presentations from the 2011 Life After Breast Cancer conference.

Penn's Abramson Cancer Center is a national cancer center in Philadelphia providing comprehensive cancer treatment, clinical trials for cancer and is a cancer research center. The National Cancer Institute has designated the Abramson Cancer Center a Comprehensive Cancer Center, one of only 40 such cancer centers in the United States.