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 mammograms 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 identified from the Carolina Mammography Registry. Mammographic assessments from community mammography practices were linked with population-based cancer outcomes. The findings of four community-based radiologists who reviewed the mammograms of 339 asymptomatic women were 93 false-negatives, 180 true-negatives, and 66 false-positives. The percentage of false-negative, true-negative and false-positive findings on breast films that reviewers evaluated was determined. The findings of the reviewers were compared with the original interpreting radiologists' assessments.

RESULTS

The overall breast-specific workup rate by the reviewing radiologists 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 breasts, the percentage of false-negative findings that were detectable was estimated to be 29%.

CONCLUSION

This peer review of screening mammograms from a population-based 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.