Death from Breast Cancer Occurs Predominantly in Women Not Participating in Mammographic Screening
Matthew Loren Webb, Blake Cady, MD, James S Michaelson, MD, PhD, Raymond A Jean, Dan Kopans, MD, Barbara L. Smith, MD, PhD
Massachusetts General Hospital, Boston, MA
PURPOSE OF STUDY
Randomized population mammographic screening trials demonstrated statistically significant mortality reduction in screened women. However, in large general populations, it is unclear how screening impacts death from breast cancer. In a previous report, 75% of breast cancer deaths occurred in the small proportion of unscreened women. That conclusion needs confirmation.
6,997 invasive breast cancer diagnoses occurred in a large hospital consortium between 1990 and 1999. Among all subsequent deaths through 2007, breast cancer deaths in
SUMMARY OF RESULTS
After 12.5 (8-17) years median follow-up, 461 deaths from breast cancer were confirmed. 72 deaths (15.6%) resulted from non-palpable screen detected cancers; 44 deaths (9.6%) resulted from palpable interval cancers, a total of 116 deaths (25.2%) were in regularly screened women. 322 deaths (69.9%) occurred in women who never had screening mammography, and 23 deaths (5%) occurred after one or more previous mammograms, none within two years of diagnosis. Thus 345 breast cancer deaths (74.8%) occurred in women not regularly screened.
The most effective method of avoiding death from breast cancer is for women to participate in regular screening mammography.
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