Breast Cancer Risks and Prevention

It seems everyone knows a woman who has been diagnosed with breast cancer. Among women in the United States, breast cancer is the second most common cancer diagnosis after skin cancer and the second leading cause of cancer-related deaths after lung cancer.

However, there’s been some good news in recent years. According to the American Cancer Society, when breast cancer is diagnosed early, the five-year survival rate is 99 percent. This is due to the early stage and small size, before it spreads to lymph nodes, nearby structures or other places outside the breast. From 2013 to 2018, breast cancer death rates in women older than 50 has gone down by 1% per year. This decrease is likely due to increased awareness, early diagnoses through annual screenings as well as better treatment options.

Breast Cancer Risk Factors

Why do some women get breast cancer and others don’t? Researchers have identified several risk factors that can make a woman more likely to develop the disease, but all women are at risk for breast cancer. That’s why mammogram screenings are recommended for women over age 45. One woman can have several risk factors and never develop breast cancer, while another might seem to be at very low risk, and still get the disease.

Some of the currently known factors that can raise your risk:

• Being a Woman and Getting Older — About two-thirds of all invasive breast cancers are diagnosed in women over age 55.
• Genetics — Women who inherited a BRCA1 or BRCA2 genetic mutation have a much higher than average lifetime risk of developing breast cancer, ranging from 45 percent to as high as 80 percent.
• Family History — Having one first-degree relative (a mother, sister or daughter) with breast cancer doubles a woman’s risk. Having two first-degree relatives raises your risk about threefold.
• Personal History — If you’ve been diagnosed with cancer in one breast, you have a higher-than-average risk of developing a new cancer in either breast. You’re also at higher risk if you have dense breasts or had radiation to the chest as a child or young adult.
• Hormonal History — You’re at higher risk if you started menstruating early (before age 12) or went through menopause later than most (after age 55).
• Childbearing History— If you’ve had no children by age 30, you’re at higher risk for breast cancer.

While you can’t change getting older or your family history, there are several known risk factors you can address to try to lower your risk of breast cancer.

• Keep your weight in check. Obesity is linked to breast cancer.
• Drink alcohol only in moderation. Population studies have found that people who drink alcohol have a higher risk of breast cancer.
• Be physically active. Many studies show that physically active women have a lower risk of breast cancer.
• Don’t smoke. While it’s not proven that smoking raises your risk of breast cancer, research shows it does raise your risk of dying if you get breast cancer.
• Avoid certain types of hormone replacement therapy after menopause. Long-term HRT with certain estrogen-progestin combinations has been found to increase breast cancer.

Breast Cancer Screening Exams

New advances in mammography such as digital breast tomosynthesis, also known as 3D mammograms, are maximizing the benefits of screening by improving breast cancer detection and overall accuracy. They also reduce false positives and unnecessary recalls.

The American Cancer Society recommends that women have yearly mammograms starting at 40-45 years of age. Other organizations say all women should have mammograms at age 50 but should have the choice to start at 40. However, basing mammogram recommendations solely on a woman’s age can be problematic as breast cancer for women in their 40s is not insignificant. It accounts for at least 20% of breast cancers in women with the most potential years of life and with more aggressive tumors. Screening for women in their 40s needs to be encouraged and supported.

If you are at very high risk of breast cancer, due to factors such as a genetic mutation or a strong family history of breast cancer, your doctor might suggest you also have regular MRI exams of your breasts.