The dilemma of recalling well-circumscribed masses in a screening population: A narrative literature review and exploration of Dutch screening practice.

BACKGROUND: In Dutch breast cancer screening, solitary, new or growing well-circumscribed masses should be recalled for further assessment. This results in cancers detected but also in false positive recalls, especially at initial screening. The aim of this study was to determine characteristics of well-circumscribed masses at mammography and identify potential methods to improve the recall strategy. METHODS: A systematic literature search was performed using PubMed. In addition, follow-up data were retrieved on all 8860 recalled women in a Dutch screening region from 2014 to 2019. RESULTS: Based on 15 articles identified in the literature search, we found that probably benign well-circumscribed masses that were kept under surveillance had a positive predictive value (PPV) of 0-2%. New or enlarging solitary well-circumscribed masses had a PPV of 10-12%. In general the detected carcinomas had a favorable prognosis. In our exploration of screening practice, 25% of recalls (2133/8860) were triggered by a well-circumscribed mass. Those recalls had a PPV of 2.0% for initial and 10.6% for subsequent screening. Most detected carcinomas had a favorable prognosis as well. CONCLUSION: To recognize malignancies presenting as well-circumscribed masses, identifying solitary, new or growing lesions is key. This information is missing at initial screening since prior examinations are not available, leading to a low PPV. Access to prior clinical examinations may therefore improve this PPV. In addition, given the generally favorable prognosis of screen-detected malignant well-circumscribed masses, one may opt to recall these lesions at subsequent screening, if grown, rather than at initial screening.

Added Value of Prereading Screening Mammograms for Breast Cancer by Radiologic Technologists on Early Screening Outcomes.

Background In the Dutch breast cancer screening program, mammograms are preread by technologists to identify possible abnormalities, leading to "warning signals" (an audible and visual alert if the technologist observed an abnormality suspicious for cancer) for radiologists. The best moment to present these warning signals is unknown. Purpose To determine the effect that blinding of technologists' warning signals has on radiologists' early screening outcome measures during interpretation of mammograms. Materials and Methods In this prospective study from September 2017 to May 2019, on alternating months, radiologists were either blinded or nonblinded to the warning signals of the technologist when interpreting screening mammograms for breast cancer. All discrepancies between radiologists and technologists were reviewed during quality assurance sessions every 6 weeks, which could result in secondary recalls. The outcome measures of this study were recall rate, cancer detection rate, and positive predictive value of recall. A χ2 test was used to test for differences between the two groups. Results During the study period, 109 596 women (mean age, 62 years ± 7 [standard deviation]), including 53 291 in the blinded and 56 305 in the nonblinded groups, participated. The overall recall rate (including secondary recalls) was lower for women in the blinded group than in the nonblinded group (blinded: 1140 of 53 291 women [2.1%], nonblinded: 1372 of 56 305 women [2.4%]; P = .001). There was no evidence of cancer detection rate differences between the groups (blinded: 349 of 53 291 women [6.5 per 1000 screening examinations], nonblinded: 360 of 56 305 women [6.4 per 1000 screening examinations]; P = .75). The blinded group thus had a higher positive predictive value of recall (blinded: 349 of 1140 women [30.6%], nonblinded: 360 of 1372 women [26.2%]; P = .02). Conclusion While interpreting screening mammograms for breast cancer, radiologists blinded to technologists' warning signals had lower recall rates with higher positive predictive values than nonblinded radiologists, yet cancer detection rates seemed to remain unchanged. See also the editorial by Hofvind and Lee in this issue. © RSNA, 2021.

Utility of Supplemental Training to Improve Radiologist Performance in Breast Cancer Screening: A Literature Review.

PURPOSE: The authors evaluate whether supplemental training for radiologists improves their breast screening performance and how this is measured. METHODS: A systematic search was conducted in PubMed on August 3, 2017. Articles were included if they described supplemental training for radiologists reading mammograms to improve their breast screening performance and at least one outcome measure was reported. Study quality was assessed using the Medical Education Research Study Quality Instrument. RESULTS: Of 2,199 identified articles, 18 were included, of which 17 showed improvement on at least one of the outcome measures, for at least one training activity or subgroup. Two measurement approaches were found. For the first approach, measuring performance on test sets, sensitivity, and specificity were the most reported outcomes (8 of 11 studies). Recall rate is the most reported outcome (6 of 7 studies) for the second approach, which measures performance in actual screening practice. The studies were mainly of moderate quality (Medical Education Research Study Quality Instrument score 11.7 ± 1.7), caused by small sample sizes and the lack of a control group. CONCLUSIONS: Supplemental training helps radiologists improve their screening performance, despite the mainly moderate quality of the studies. There is a need for better designed studies. Future studies should focus on performance in actual screening practice and should look for methods to isolate the training effect. If test sets are used, focus should be on knowledge about correlation between performance on test sets and actual screening practice.

Value of audits in breast cancer screening quality assurance programmes.

OBJECTIVES: Our aim was to retrospectively evaluate the results of all audits performed in the past and to assess their value in the quality assurance of the Dutch breast cancer screening programme. METHODS: The audit team of the Dutch Reference Centre for Screening (LRCB) conducts triennial audits of all 17 reading units. During audits, screening outcomes like recall rates and detection rates are assessed and a radiological review is performed. This study investigates and compares the results of four audit series: 1996-2000, 2001-2005, 2003-2007 and 2010-2013. RESULTS: The analysis shows increased recall rates (from 0.66%, 1.07%, 1.22% to 1.58%), increased detection rates (from 3.3, 4.5, 4.8 to 5.4 per 1000) and increased sensitivity (from 64.5%, 68.7%, 70.5% to 71.6%), over the four audit series. The percentage of 'missed cancers' among interval cancers and advanced screen-detected cancers did not change (p = 0.4). CONCLUSIONS: Our audits not only provide an opportunity for assessing screening outcomes, but also provide moments of self-reflection with peers. For radiologists, an accurate understanding of their performance is essential to identify points of improvement. We therefore recommend a radiological review of screening examinations and immediate feedback as part of an audit. KEY POINTS: • Radiological review and immediate feedback are recommended as part of an audit. • For breast screening radiologists, audits provide moments of self-reflection with peers. • Radiological review of screening examinations provides insights in recall behaviour. • Accurate understanding of radiologists' performance is essential to identify points of improvement.