Breast cancer affects one in eight women during their lives. No one knows why some women get breast cancer, but there are many risk factors. Risks that you cannot change include
Age - the risk rises as you get older
Genes - two genes, BRCA1 and BRCA2, greatly increase the risk. Women who have family members with breast or ovarian cancer may wish to be tested for the genes.
Personal factors - beginning periods before age 12 or going through menopause after age 55
Other risks include obesity, using hormone replacement therapy (also called menopausal hormone therapy), taking birth control pills, drinking alcohol, not having children or having your first child after age 35, and having dense breasts.
Symptoms of breast cancer may include a lump in the breast, a change in size or shape of the breast, and discharge from a nipple. Breast self-exams and mammography can help find breast cancer early, when it is most treatable. One possible treatment is surgery. It could be a lumpectomy or a mastectomy. Other treatments include radiation therapy, chemotherapy, hormone therapy, and targeted therapy. Targeted therapy uses drugs or other substances that attack cancer cells with less harm to normal cells.
Men can have breast cancer, too, but it is rare.
NIH: National Cancer Institute
