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More about Breast Cancer:
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There are a number of risk factors for the development of breast cancer, including:
- family history of breast cancer in mother or sister
- early onset of menstruation and late menopause
- reproductive history: women who had no children or have children after age 30 and women who have never breastfed have increased risk
- history of abnormal breast biopsies
Though these are recognized risk factors, it is important to note that more than 70% of women who get breast cancer have no known risk factors. Having several risk factors may boost a woman's chances of developing breast cancer, but the interplay of predisposing factors is complex. In addition to those accepted factors listed above, some studies suggest that high-fat diets, obesity, or the use of alcohol may contribute to the risk profile. Another factor that may contribute to a woman's risk profile is hormone replacement therapy (HRT).
HRT provides significant relief of menopausal symptoms, prevention of osteoporosis, and possibly protection from cardiovascular disease and stroke. However, studies show that there is a small increased risk of developing breast cancer with HRT use. Thus, the use of hormone replacement therapy should be based on personal risk factors.
Of all the risk factors listed above, family history is the most important. In The Biological Basis of Cancer, the authors estimate that probably about half of all familial breast cancer cases (families in which there is a high breast cancer frequency) have mutations affecting the tumor suppressor gene BRCA-1. Another gene (BRCA-2) also appears to confer inherited vulnerability to early-onset breast cancers. However, breast cancer due to heredity is only a small proportion of breast cancer cases; only 5%–10% of all breast cancer cases will be women who inherited a susceptibility through their genes. Nevertheless, when the family history is strong for development of breast cancer, a woman's risk is increased.
Not all lumps detected in the breast are cancerous. Fibrocystic changes in the breast are extremely common. Also known as fibrocystic condition of the breast, fibrocystic changes are a leading cause of non-cancerous lumps in the breast. Fibrocystic changes also cause symptoms of pain, swelling, or discharge and may become evident to the patient or physician as a lump that is either solid or filled with fluid. Complete diagnostic evaluation of any significant breast abnormality is mandatory because though women commonly develop fibrocystic changes, breast cancer is common also, and the signs and symptoms of fibrocystic changes overlap with those of breast cancer.
— Richard A. McCartney, M.D.
