Increasing The Accuracy of Diagnostic Performance Estimates for Surveillance Mammography After Breast Cancer Treatment
New BCSC study finds mammography performed at intervals less than one year can impact diagnostic performance calculations and proposes a solution for eliminating artificial inflation of cancers detected
Current guidance from the American College of Radiology for calculating diagnostic performance can result in artificial inflation of the number of cancers detected when mammograms are performed more than once in an annual interval, which is often observed for women with a personal history of breast cancer. A new BCSC study proposes a way to address this challenge.
Dr. Janie M. Lee from the University of Washington and BCSC colleagues evaluated 117,971 surveillance mammograms from 2007-2016 in women with treated breast cancer. They assessed the change in performance measures using a truncated follow-up interval that eliminated shared follow-up periods for mammograms performed more frequently than annually, compared performance using the standard one-year follow-up. The study team found that 20% of mammograms (n=23,533) were followed by another surveillance mammogram within one year. Standard follow-up identified 1,597 mammograms that were associated with second breast cancers. With truncated follow-up, the breast cancer status of 179 mammograms (11.2%) was revised, resulting in 1,418 mammograms associated with unique second breast cancers. The interval cancer rate decreased with truncated versus standard follow-up (3.6 versus 4.9 per 1,000 mammograms, respectively), with a difference (95%CI) of -1.3 (-1.6, -1.1). The overall sensitivity increased to 70.4% from 63.7%, for the truncated versus standard follow-up, with a difference (95%CI) of 6.6% (5.6%, 7.7%). The specificity remained stable at 98.1%. The study concluded that applying truncated follow-up, if less than one year to the next surveillance mammogram, resulted in more accurate estimates of diagnostic performance and enabled improved understanding of performance compared with national benchmarks.
Lee JM, Ichikawa LE, Wernli KJ, Bowles EJA, Specht JM, Kerlikowske K, Miglioretti DL, Lowry KP, Tosteson ANA, Stout NK, Houssami N, Onega T, Buist DSM. Impact of Surveillance Mammography Intervals Less Than One Year on Performance Measures in Women With a Personal History of Breast Cancer. Korean J Radiol. 2023;24(8):729-38. doi: 10.3348/kjr.2022.1038. PubMed PMID: 37500574; PMCID: PMC10400369. [Link].
Posted by: Janie Lee