Some statistics
The chance of a woman receiving a false positive result after 10 yearly mammograms is about 50-60 percent. The high false positive result comes from wanting to reduce false negatives to as low a percentage as possible. However, mammography may miss nearly 30 percent of breast cancers.
SEER Cancer Statistics Review (CSR) 1975-2013 Updated September 12, 2016
A positive mammography result means a biopsy is performed. Doctors correctly identify invasive breast cancer 96 % of the time and correctly identify normal tissue 87 % of the time.
Doctors misdiagnose ductal carcinoma in situ, or DCIS, 16 % of the time, and atypia (atypical hyperplasia) 52 % of the time. Both conditions can go on to become invasive cancer.
17 % of the readings are false positives for atypia and that means those women are likely to undergo surgery and other treatment they do not need. 32 % are false negatives meaning a substantial number of women not knowing they are at increased risk of cancer.
Diagnostic Concordance Among Pathologists Interpreting Breast Biopsy Specimens