Understanding Mammograms and Your Risk of Breast Cancer - National Cancer Institute

Understanding Mammograms and Your Risk of Breast Cancer - National Cancer Institute

1. What is my risk of getting breast cancer? Age is the most important risk factor for breast cancer. The older you are, the greater your chance of developing the disease. Breast cancer is more common in women over age 60 and is relatively uncommon in women under age 40.
   Learn more:
   
   • Read the NCI fact sheet, Probability of Breast Cancer in American Women
   • Visit the NCI Web site, Cancer Risk: Understanding the Puzzle
     
2. What factors might increase my risk of getting breast cancer? Although age is the most important risk factor for breast cancer, the risk is not the same for all women of a given age group. Women with the following factors have an increased risk of developing breast cancer:
   
   • a personal or family history of breast cancer
   • certain breast changes found on biopsy
   • certain genetic changes
   • menstrual periods before age 12 or menopause after age 55
   • having a first child after age 30 or never having a child
   • long-term use (more than 5 years) of menopausal hormone therapy
   • dense breast tissue
   • radiation therapy to the chest before age 30
   • alcohol use
   • having taken the drug diethylstilbestrol (DES) during pregnancy
   • obesity
   • lack of exercise
   Learn more:
   
   • See Question 6 in the NCI fact sheet, Mammograms
     
3. What is a mammogram? Mammograms are x-ray pictures of the breast that are effective for finding breast cancer.  Mammograms can be used to check for breast cancer in women who have no signs or symptoms of the disease. This type of mammogram is called a screening mammogram. Mammograms also can be used to check for breast cancer after a lump or other sign or symptom of the disease has been found. This type of mammogram is called a diagnostic mammogram. A diagnostic mammogram also can be used to evaluate changes found during a screening mammogram or to view breast tissue when it is difficult to obtain a screening mammogram because of special circumstances, such as the presence of breast implants.
   Learn more:
   
   • Read the section, “Finding Breast Changes,” in the NCI booklet Understanding Breast Changes: A Health Guide for Women
     
4. When and how often should I get a mammogram? If you are age 40 or older, you should have mammograms every 1 to 2 years. Women who are at higher than average risk of breast cancer should talk with their health care providers about whether to have mammograms before age 40 and how often to have them.
5. What are the benefits of getting a mammogram? Several large studies conducted around the world show that mammograms reduce the number of deaths from breast cancer for women ages 40 to 74, especially for those over age 50. In women under age 40, studies conducted to date have not shown a benefit from regular screening mammograms, or from a baseline screening mammogram (a mammogram used for comparison).
6. What are the potential harms of getting a mammogram?
   
   
   • Overdiagnosis and overtreatment: Some tumors found on mammograms may never cause symptoms or become life-threatening. When such tumors are found, having treatment would not extend life and may instead cause serious treatment-related side effects.
   • False-negative test results: This means that a mammogram may appear to be normal even though breast cancer is present.
   • False-positive test results: This means that a mammogram may appear to be abnormal even though no cancer is present.
   • Radiation exposure: Mammograms expose the breast to radiation. The risk of harm from this radiation exposure is slight, but repeated x-rays have the potential to cause cancer. The benefits, however, nearly always outweigh the risk. Women should talk with their health care providers about the need for each x-ray.
   Learn more:
   
   • Read the section, “Risks of Breast Cancer Screening,” in the Breast Cancer Screening (PDQ®) summary for patients
7. Where can I go to get a mammogram? How much will it cost? Will insurance pay? You can get high-quality mammograms in breast clinics, hospital radiology departments, mobile vans, private radiology offices, and doctors’ offices.
   The cost of screening mammograms varies by state and by facility, and can depend on insurance coverage. Most states have laws requiring health insurance companies to reimburse all or part of the cost. Women are encouraged to contact their mammogram facility or their health insurance company for information about cost and coverage. Screening mammograms are covered once every 12 months for all women with Medicare age 40 and older.
   Learn more:
   
   • Find a mammogram facility near where you live or work by calling 1–800–4–CANCER (1–800–422–6237) or by searching the Food and Drug Administration’s Mammography Facility Database
   • Low-income, uninsured, and underinsured women may be eligible for breast and cervical cancer screening and diagnostic services through the National Breast and Cervical Cancer Early Detection Program (NBCCEDP). To find a local program and see if you qualify, go to http://apps.nccd.cdc.gov/cancercontacts/nbccedp/contacts.asp
     
8. How will I learn about my results? You should get a written report within 30 days of your mammogram. If your results were normal, your breast tissue shows no signs of a mass or calcification. Visit your health care provider if you notice a breast change before your next appointment. If your results were abnormal, a breast change was found. It may be benign (not cancer), premalignant (may become cancer), or cancer. Keep in mind that most breast changes are not cancer. But all changes need to be checked, and more tests may be needed.
   Learn more:
   
   • Read the section, “Getting Your Mammogram Results,” in the NCI booklet Understanding Breast Changes: A Health Guide for Women
     
9. How can we help? NCI offers comprehensive research-based information for patients and their families, health professionals, cancer researchers, advocates, and the public.
   
   • Call NCI’s Cancer Information Service at 1–800–4–CANCER (1–800–422–6237)
   • Visit us at http://www.cancer.gov/ or http://www.cancer.gov/espanol
   • Chat with us using LiveHelp, NCI’s instant messaging service, at https://livehelp.cancer.gov/
   • E-mail us at cancergovstaff@mail.nih.gov
   • Order publications at http://www.cancer.gov/publications or by calling 1–800–4–CANCER
   • Get help with quitting smoking at 1–877–44U–QUIT (1–877–448–7848)