Breast Cancer

Breast cancer is a type of cancer that occurs when a malignant tumor forms from cells within the breast. It occurs most frequently in women, however, men can develop breast cancer, although much less frequently. The American Cancer Society estimates that 1 in every 8 women will develop breast cancer in their lifetime, making it the most common cancer among women, aside from skin cancer.

Risk Factors and Causes of Breast Cancer

Research is ongoing to identify the exact causes of breast cancer. Researchers have, however, identified several breast cancer risk factors. A risk factor is something that increases the chance that a person will develop a disease. It is not a guarantee and does not predict a future diagnosis. Risk factors for breast cancer include:
Age: As we grow older, our risk of developing breast cancer increases. It is estimated that 80% of women diagnosed with breast cancer are 50 or older. This doesn't mean that younger women aren't at risk. Young women are diagnosed with breast cancer, just much less frequently.

Family and Personal History of Breast Cancer. Having a mother, sister, or daughter with breast cancer doubles your risk of the disease. While family history can play a role in breast cancer development, women shouldn't subscribe to the popular belief that women without a family history of breast cancer aren't at risk. The American Cancer Society estimates that 70 to 80% of women with breast cancer do not have a family history that includes breast cancer.

Women who have previously been diagnosed and treated for breast cancer are at a greater risk of developing breast cancer again.

Race. Of all women, Caucasian women are diagnosed more frequently than women of other races. Though Caucasian women are the most at risk, it is African American women who die of the disease the most. Asian, Native American, and Hispanic women have less of a risk.

Alcohol Consumption. Women who drink alcohol increase their breast cancer risk and the risk is heightened with the amount of alcohol consumed. Women who drink 2-5 drinks a day increase their risk by 1 1/2 when compared to women who do not drink alcohol. One drink a day only slightly elevates a woman's risk.

• Alcohol and Your Breast Cancer Risk: Lifestyle Factors You Can Change

Family Planning Choices. Women who choose not to have children or have them after age 30 somewhat increase their risk of breast cancer.

• How Pregnancy Decreases Risk of Breast Cancer

Genetics Genetics may play a role in up to 10% of women diagnosed with breast cancer. Hereditary breast cancer occurs when a mutated gene has been passed down from a parent. The most common genetic mutation is that of the BRCA gene pair, referred to as "BRCA1" and "BRCA2". These genes are responsible for regulating cell growth and repairing damaged DNA, but do not properly function if mutated. Those who are found through genetic testing to be carriers of mutated BRCA genes are at an increased risk of developing breast cancer. Other gene types have been associated to breast cancer, but not as prevalently as the BRCA genes.