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Breast cancer is the second leading cause of cancer death in women in the U.S.
 

What are a woman's chances of getting breast cancer as she gets older?
Chance...
by age 30...	1 out of 2,525
by age 40...	1 out of 217
by age 50...	1 out of 50
by age 60...	1 out of 24
by age 70...	1 out of 14
by age 80...	1 out of 10
Source: NCI Surveillance, Epidemiology, and End Results Program & American Cancer Society, 1993

• If detected early, most breast cancer can be treated successfully.
   

• Annual mammographic screening in women between 50-69 has been shown to reduce mortality by up to 30% (Fletcher, et al., 1993).
• Meta-analysis of trials for the U.S. Preventive Services Task Force (USPSTF) found a small benefit in mortality with screening every 1-2 years.
• Screening mammograms accounted for about 46% of the reduction in breast cancer mortality from 1975-2000, based on the recent analysis of seven statistical models of breast cancer incidence and mortality during this period. Adjuvant treatment (e.g., chemotherapy and tamoxifen) accounted for about 54% of the reduction in deaths during this period (Berry, 2005).
• Sensitivity of mammograms increase with increasing age and with subsequent studies. With regular screening intervals, radiologists have baseline studies that are used to compare all future studies, which increases sensitivity.
• The sensitivity of mammographic findings range from 54-58% in women under 40 years, to a sensitivity of 81-94% in women over 65 years, based on data from population-based cancer registries. The sensitivity depends on patient factors (e.g., age, use of hormone replacement therapy, breast density), technology (e.g., quality of images), and provider factors (interpretitive skill of the radiologist). The Mammography Quality Standards Act (MQSA) of 1992 and the American College of Radiology Mammography Accreditation Program have significantly contributed to improved mammography technique, lower radiation dose, and better training of personnel (NCI, 2005).
   
• Several risk assessment tools (Gail and Claus) are available to determine a woman's lifetime risk of developing breast cancer, but have not been validated in minority populations and can underestimate risk for women with a familiy history of hereditary breast cancer. A comparison of these screening tools is available on the National Cancer Institute web site, Genetics of Breast and Ovarian Cancer, Models for Prediction of Breast Cancer Risk (2005).

The breast cancer risk assessment tools can be used to help determine recommendations for screening and are available at:

• National Cancer Institute, Breast cancer risk assessment tool, based on the Gail Model for 5 year Risk of Breast Cancer
• Claus Model (1994)

• Risks of mammograms include false positives, which can be associated with anxiety and unnecessary biopsies. Women's risk of having a false positive is 10.7% with each mammogram. Approximately 50% of women will experience a false positive result after 10 years of annual screening. (Elmore, 1998).
• A younger age, personal history of breast biopsies, family history of breast cancer, estrogen use, longer interval between screenings and radiologist propensity to read films as abnormal were all associated with risk of having a false positive mammogram.
• Although having an abnormal mammogram can lead to additional views with mammography or other procedures, having such an abnormality usually does affect women's participation in ongoing mammogram screenings. (Gordon, 2005).

 

Meta-analysis - a special statistical summary of several individual studies into one overall conclusion. Sensitivity - the ability of a test to correctly identify someone who has the disease. The percent of true positives--positive mammogram in a woman who actually has breast cancer. Specificity - the ability of a test to correctly identify someone who does not have the disease. The percent of true negatives--negative mammogram in a woman who does not have breast cancer.