Reassessment of breast cancers missed during routine screening mammography: A community-based study

OBJECTIVE. The purpose of this study was to have a series of screening mamm ograms from routine practice, including false-negative results, reviewed by peer community-based experienced radiologists to determine the percentage of these false-negative findings that might be considered detectable. MATERIALS AND METHODS. All screening cases for 1997 and 1998 were identifie d from the Carolina Mammography Registry. Mammographic assessments from com munity mammography practices were linked with population-based cancer outco mes. The findings of four community-based radiologists who reviewed the mam mograms of 339 asymptomatic women were 93 false-negatives, 180 true-negativ es, and 66 false-positives. The percentage of false-negative, true-negative and false-positive findings on breast films that reviewers evaluated was d etermined. The findings of the reviewers were compared with the original in terpreting radiologists' assessments. RESULTS. The overall breast-specific workup rate by the reviewing radiologi sts was 21%. The average workup rate for the false-negative findings was 42 % (range, 35-51%). Adjusting for the 13% workup rate in the cancer-free bre asts, the percentage of false-negative findings that were detectable was es timated to be 29%. CONCLUSION. This peer review of screening mammograms from a population-base d screening registry estimated a missed detectable cancer rate of 29%. Thus , 71% of cancers missed at screening would not have been worked up by peers in the same community.