Breast cancer screening

Breast cancer screening uses tests and exams to look for breast cancer in people who don’t have any signs or symptoms. Instead of waiting for symptoms to emerge, screening tests allow you to get checked for breast cancer at any time. These tests don’t prevent breast cancer, but getting screened regularly may lower the risk of dying from breast cancer by finding it early.

Breast cancer screening imaging tests and exams

Mammography

Mammograms, or X-rays of the breast, are the most effective way to find breast cancer early. Many years of research have proven that regular mammograms may help diagnose cancer early, avoiding the need for aggressive treatments and increasing the likelihood that treatment is successful. Digital or 3D mammograms, a newer type of mammogram, are often even better at spotting small breast tumors, especially in women with dense breast tissue.

Breast magnetic resonance imaging (MRI)

A breast MRI takes detailed images of the inside of the breast. Because breast MRIs can often lead to false positives, they are only used to screen for breast cancer in women whose risk of developing breast cancer is high.

Once your mammogram and breast MRI results are ready, your care team will describe them using a standardized system called BI-RADS.

Clinical breast exams or breast self-exams

Breast exams involve you (or a doctor or nurse during a clinical exam) feeling your breast to check for any abnormal areas or lumps. These exams are not currently believed to be an important part of screening. However, you should still be on the lookout for any changes in your breast and report them to your doctor if they occur.

Breast cancer screening guidelines

The decision of when and how often to have breast cancer screening is up to you, based on discussions with your doctor about your personal risks for breast cancer and the benefits of screening.

Breast cancer screening guidelines are generally divided into two groups:

• Guidelines for women at average risk of getting breast cancer
• Guidelines for women at high risk of developing breast cancer

Breast cancer risk is determined based on a combination of your risk factors for breast cancer and other data sets or models, but it is only an estimate. It can vary depending on the assessment tools used.

Screening for women at average risk

According to the American Cancer Society (ACS), you’re at average risk if you meet the following criteria:

• No personal history of breast cancer
• No immediate family history of breast cancer
• No genetic mutations that increase the risk of breast cancer, like a BRCA gene mutation
• No past radiation therapy in the chest area before age 30

Women who meet these criteria are then split into age groups. The guidelines of the American College of Radiology (ACR) and the American College of Surgeon's National Accreditation Program for Breast Centers state that:

• Age 40: Women at average risk start getting annual mammograms.
• Age 55-74: Women at average risk should get mammograms every one to two years.
• Over 75: Women at average risk should continue to get mammograms depending on their overall health, including a life expectancy of 10 or more years.
  

Screening for women at high risk

Women who face a higher risk of getting breast cancer will likely be advised to undergo screening earlier, more often or using more thorough tests. However, like the guidelines for average-risk women, different organizations offer different recommendations for the high-risk group.

According to the ACS, you’re high risk if you:

• Have a 20 to 25 percent higher lifetime risk of getting breast cancer based on risk assessment tools
• Had genetic testing that found a mutation known to increase the risk of breast cancer in the BRCA1 or BRCA2 gene
• Have not had genetic testing, but have an immediate family member with a BRCA1 or BRCA2 gene mutation
• Had radiation therapy in your chest area between ages 10 to 30
• Have or have an immediate family member who has Li-Fraumeni syndrome, Cowden syndrome or Bannayan-Riley-Ruvalcaba syndrome

The ACR recommends that women be assessed for breast cancer risk by the age of 30, so that those at high risk may be evaluated to determine whether screening should begin before the age of 40. For women with dense breasts, the ACR recommends that, in addition to mammograms, they undergo contrast-enhanced breast MRI, and if they can't undergo an MRI, that they consider an ultrasound.

You and your doctor can go over all factors that define your risk and the various recommendations to help you make an informed and shared decision on when to start screening, which tools to use and how frequently to have it done.