Breast cancer forms in the breast tissues and is the second leading cause of death among women. Symptoms include a painless breast lump, changes in breast size or shape, swelling in the armpit, or nipple changes. Risk factors include being female, older age, family or personal history, genetic factors, early menarche or late menopause, not having children or having a first child after age 25. Self exams are important for early detection by feeling the entire breast area and looking for changes in skin texture or nipple inversion. Prevention includes self exams, education, and learning about one's own body.