1. Breast Cancer Slideshow Pictures
2. Take the Breast Cancer Quiz
3. Disease Prevention in Women Slideshow Pictures

Medical Author:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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In this Article

• Introduction to breast cancer prevention
• What are the biological causes of breast cancer?
• What are the risk factors for developing breast cancer?
• What is the importance of early breast cancer detection?
• What are the advantages and limitations of mammography?
• How frequently should women undergo mammography and breast examinations?
• What is the risk of radiation with repeated mammography screening over the years?
• Are there any controversies in the area of breast cancer screening?
• How helpful are BRCA1 and BRCA2 genetic tests in identifying women at risk?
• What is the link between estrogen and breast cancer?
• What are breast cancer prevention treatments?
• Are there other breast cancer prevention measures?
• Conclusion
• Breast Cancer Prevention Index

In special circumstances, genetic tests can be very helpful both in identifying exceptionally high-risk patients and reducing the level of concern for others. We also now know that the presence of one of these genetic defects does not cause cancer in every patient. The cancers that do occur may also behave somewhat differently than non-BRCA-associated tumors. There is some evidence that they have a better outcome.

Before genetic tests are conducted, individuals being tested must have thorough counseling. A clear understanding of the limitations of the tests and the problems they may pose must precede the testing. The patient must know the meaning of the possible results, whichever way they may turn out, before testing. They should also have settled on a plan for each possible outcome of the test results. Often, the best way to evaluate a potential genetic risk is to test a relative who has already been diagnosed with breast cancer. If the relative's genetic testing (which must cover a large number of possible mutations) proves negative, then there is no need to perform genetic testing on the concerned individual. But the concerned individual should still undergo close monitoring with breast examinations and mammograms. If the test is positive on the relative, then that specific mutation is the only one that needs to be checked in the concerned individual and the other family members.

Estrogen is a female hormone that is produced by the ovaries. During the reproductive years, a woman's body is exposed to high levels of estrogen. After menopause, the production of estrogen by the ovaries decreases. Estrogen is sometimes prescribed to treat some of the problems often associated with menopause, such as hot flashes, night sweats, sleeplessness, and vaginal dryness. Estrogen has the additional benefit of prevention of bone thinning (osteoporosis). However, results from a large clinical trial of postmenopausal women receiving hormone therapy (HT) released in 2002 showed that the overall risks of estrogen plus progestin therapy outweighed the benefits of hormone therapy. Combined hormone therapy with estrogen and progestin was shown to increase the risk of heart disease, stroke, and blood clots.

High levels of estrogen over long periods also increase the risk of developing breast and uterine cancers. Estrogen stimulates the cells of the breast and the uterine lining to grow and divide. Breast cells that are actively dividing are believed to have a greater chance of DNA damage as well as a higher number of cells that already have DNA damage. A higher number of cells with DNA damage elevate the risk of cancer development.

Women who have an early onset of their menstrual period (or menses) and late menopause are more likely to develop breast cancer than women with late menses onset and early menopause. This difference is believed to be attributable to the longer period of estrogen exposure in the first group.