The effect of false positive breast screening examinations on subsequent attendance: retrospective cohort study

Feasibility study comparing synthesized mammography with digital breast tomosynthesis and digital mammography for simulated first round screening in a single BreastScreen NSW centre

INTRODUCTION

While digital breast tomosynthesis (DBT) has proven to enhance cancer detection and reduce recall rates (RR), its integration into BreastScreen Australia for screening has been limited, in part due to perceived cost implications. This study aims to assess the cost effectiveness of digital mammography (DM) compared with synthesized mammography and DBT (SM + DBT) in a first round screening context for short-term outcomes.

METHODS

Clients recalled for nonspecific density (NSD) as a single lesion by both readers at the Northern Sydney Central Coast BreastScreen service in 2019 were included. Prior images were excluded to simulate first-round screening. Eleven radiologists read DM and synthesized mammography with DBT (SM + DBT) images 4 weeks apart. Recall rates (RR), reading time, and diagnostic parameters were measured, and costs for screen reading and assessment were calculated.

RESULT

Among 65 clients studied, 13 were diagnosed with cancer, with concordant cancer recalls. SM + DBT reduced recall rates (RR), increased reading time, maintained cancer detection sensitivity, and significantly improved other diagnostic parameters, particularly false positive rates. Benign biopsy recalls remained equivalent. While SM + DBT screen reading cost was significantly higher than DM (DM AU$890 ± 186 vs SM + DBT AU$1279 ± 265; P < 0.001), the assessment cost (DM AU$29,504 ± 9427 vs SM + DBT AU$18,021 ± 5606; P < 0.001), and combined screen reading and assessment costs were significantly lower (DM AU$30,394 ± 9508 vs SM + DBT AU$19,300 ± 5721; P = 0.001). SM + DBT screen reading and assessment of 65 patients resulted in noteworthy cost savings (AU$11,094), equivalent to assessing 12 additional clients.

CONCLUSION

In first round screening, DBT yields significant cost savings by effectively reducing unnecessary recalls to assessment while maintaining diagnostic efficacy.

Predictors of re-attendance at biennial screening mammography following a false positive referral: A study among women in the south of the Netherlands

AIM

A false positive (FP) referral after screening mammography may influence a woman's likelihood to re-attend the screening program. The impact of having a FP result in the first or subsequent screening round on re-attendance after a FP result was investigated. In addition, we aimed to study differences in re-attendance rates between women who underwent non-invasive and invasive additional examinations as part of the diagnostic work-up following a FP referral.

METHODS

A consecutive series of 13,597 women with a FP referral following biennial screening mammography in the south of the Netherlands between 2009 and 2019 was included.

RESULTS

The screening re-attendance rate was 81.2% after a FP referral, and 91.3% when also including women who had clinical mammographic follow-up. Women who received a FP referral in the first screening round were less likely to re-attend the screening programme in the following three years, compared to those with a FP test in any subsequent round (odds ratio (OR): 0.59, 95%-confidence interval (CI): 0.51-0.69). Women with a FP referral who underwent invasive examinations after referral were less likely to re-attend the screening programme than those who only received additional imaging (OR, 0.48; 95% CI 0.36-0.64).

CONCLUSION

Women with a FP referral are less likely to re-attend the screening programme if this referral occurs at their first screening round or when they undergo invasive diagnostic workup. Hospitals and screening organizations should prioritize informing women about the importance of re-attending the programme following a FP referral.

False-positive recalls in the prospective Malmö Breast Tomosynthesis Screening Trial

OBJECTIVES

To evaluate the total number of false-positive recalls, including radiographic appearances and false-positive biopsies, in the Malmö Breast Tomosynthesis Screening Trial (MBTST).

METHODS

The prospective, population-based MBTST, with 14,848 participating women, was designed to compare one-view digital breast tomosynthesis (DBT) to two-view digital mammography (DM) in breast cancer screening. False-positive recall rates, radiographic appearances, and biopsy rates were analyzed. Comparisons were made between DBT, DM, and DBT + DM, both in total and in trial year 1 compared to trial years 2 to 5, with numbers, percentages, and 95% confidence intervals (CI).

RESULTS

The false-positive recall rate was higher with DBT, 1.6% (95% CI 1.4; 1.8), compared to screening with DM, 0.8% (95% CI 0.7; 1.0). The proportion of the radiographic appearance of stellate distortion was 37.3% (91/244) with DBT, compared to 24.0% (29/121) with DM. The false-positive recall rate with DBT during trial year 1 was 2.6% (95% CI 1.8; 3.5), then stabilized at 1.5% (95% CI 1.3; 1.8) during trial years 2 to 5. The percentage of stellate distortion with DBT was 50% (19/38) trial year 1 compared to 35.0% (72/206) trial years 2 to 5.

CONCLUSIONS

The higher false-positive recall rate with DBT compared to DM was mainly due to an increased detection of stellate findings. The proportion of these findings, as well as the DBT false-positive recall rate, was reduced after the first trial year.

CLINICAL RELEVANCE STATEMENT

Assessment of false-positive recalls gives information on potential benefits and side effects in DBT screening.

KEY POINTS

• The false-positive recall rate in a prospective digital breast tomosynthesis screening trial was higher compared to digital mammography, but still low compared to other trials. • The higher false-positive recall rate with digital breast tomosynthesis was mainly due to an increased detection of stellate findings; the proportion of these findings was reduced after the first trial year.

Factors associated with attendance at screening for breast cancer: a systematic review and meta-analysis

OBJECTIVE

Attendance at population-based breast cancer (mammographic) screening varies. This comprehensive systematic review and meta-analysis assesses all identified patient-level factors associated with routine population breast screening attendance.

DESIGN

CINAHL, Cochrane Library, Embase, Medline, OVID, PsycINFO and Web of Science were searched for studies of any design, published January 1987-June 2019, and reporting attendance in relation to at least one patient-level factor.

DATA SYNTHESIS

Independent reviewers performed screening, data extraction and quality appraisal. OR and 95% CIs were calculated for attendance for each factor and random-effects meta-analysis was undertaken where possible.

RESULTS

Of 19 776 studies, 335 were assessed at full text and 66 studies (n=22 150 922) were included. Risk of bias was generally low. In meta-analysis, increased attendance was associated with higher socioeconomic status (SES) (n=11 studies; OR 1.45, 95% CI: 1.20 to 1.75); higher income (n=5 studies; OR 1.96, 95% CI: 1.68 to 2.29); home ownership (n=3 studies; OR 2.16, 95% CI: 2.08 to 2.23); being non-immigrant (n=7 studies; OR 2.23, 95% CI: 2.00 to 2.48); being married/cohabiting (n=7 studies; OR 1.86, 95% CI: 1.58 to 2.19) and medium (vs low) level of education (n=6 studies; OR 1.24, 95% CI: 1.09 to 1.41). Women with previous false-positive results were less likely to reattend (n=6 studies; OR 0.77, 95% CI: 0.68 to 0.88). There were no differences by age group or by rural versus urban residence.

CONCLUSIONS

Attendance was lower in women with lower SES, those who were immigrants, non-homeowners and those with previous false-positive results. Variations in service delivery, screening programmes and study populations may influence findings. Our findings are of univariable associations. Underlying causes of lower uptake such as practical, physical, psychological or financial barriers should be investigated.

TRIAL REGISTRATION NUMBER

CRD42016051597.

Artificial intelligence for the real world of breast screening

Breast cancer screening with mammography reduces mortality in the women who attend by detecting high risk cancer early. It is far from perfect with variations in both sensitivity for the detection of cancer and very wide variations in specificity, leading to unnecessary recalls and biopsies. Over the last 12 months several papers have reported on AI algorithms that perform as well as human readers on large well curated population data sets. The nature of the test sets, the way the gold standard has been calculated, the definition of a positive call, and the statistics used all influence the results. Historically retrospective studies have not predicted the real-life performance of radiologist plus machine. So, it is important to perform prospective studies before introducing Artificial intelligence into real world breast screening.

Flemish breast cancer screening programme: 15 years of key performance indicators (2002-2016)

Background

We examined 15 years of key performance indicators (KPIs) of the population-based mammography screening programme (PMSP) in Flanders, Belgium.

Methods

Individual screening data were linked to the national cancer registry to obtain oncological follow-up. We benchmarked crude KPI results against KPI-targets set by the European guidelines and KPI results of other national screening programmes. Temporal trends were examined by plotting age-standardised KPIs against the year of screening and estimating the Average Annual Percentage Change (AAPC).

Results

PMSP coverage increased significantly over the period of 15 years (+ 7.5% AAPC), but the increase fell to + 1.6% after invitation coverage was maximised. In 2016, PMSP coverage was at 50.0% and opportunistic coverage was at 14.1%, resulting in a total coverage by screening of 64.2%. The response to the invitations was 49.8% in 2016, without a trend. Recall rate decreased significantly (AAPC -1.5% & -5.0% in initial and subsequent regular screenings respectively) while cancer detection remained stable (AAPC 0.0%). The result was an increased positive predictive value (AAPC + 3.8%). Overall programme sensitivity was stable and was at 65.1% in 2014.

In initial screens of 2015, the proportion of DCIS, tumours stage II+, and node negative invasive cancers was 18.2, 31.2, and 61.6% respectively. In subsequent regular screens of 2015, those proportions were 14.0, 24.8, and 65.4% respectively. Trends were not significant.

Conclusion

Besides a suboptimal attendance rate, most KPIs in the Flemish PMSP meet EU benchmark targets. Nonetheless, there are several priorities for further investigation such as a critical evaluation of strategies to increase screening participation, organising a biennial radiological review of interval cancers, analysing the effect that preceding opportunistic screening has on the KPI for initial screenings, and efforts to estimate the impact on breast cancer mortality.

How do women experience a false-positive test result from breast screening? A systematic review and thematic synthesis of qualitative studies

BACKGROUND

This is the first review to identify, appraise and synthesise women's experiences of having a false-positive breast screening test result.

METHODS

We systematically searched eight databases for qualitative research reporting women's experiences of receiving a false-positive screening test result. Two reviewers independently screened articles. Eight papers reporting seven studies were included. Study quality was appraised. Data were thematically synthesised.

RESULTS

Women passively attended screening in order to prove their perceived good health. Consequently, being recalled was unexpected, shocking and disempowering: women felt without options. They endured great uncertainty and stress and sought clarity about their health (e.g. by scrutinising the wording of recall letters and conversations with healthcare professionals). Their result was accompanied by relief and welcome feelings of certainty about their health, but some received unclear explanations of their result, contributing to lasting breast cancer-related worry and an ongoing need for further reassurance.

CONCLUSION

The organisation of breast screening programmes may constrain choice for women: they became passive recipients. The way healthcare professionals verbally communicate results to women may contribute to lasting breast cancer-related worry. Women need more reassurance, emotional support and answers to their questions before and during screening assessment, and after receiving their result.

The Potential Impact of Digital Breast Tomosynthesis on the Benign Biopsy Rate in Women Recalled within the UK Breast Screening Programme

Background Multiple studies showed digital breast tomosynthesis (DBT) has a higher cancer detection rate and a lower recall rate than full-field digital mammography (FFDM). However, there is a paucity of studies on whether the benign biopsy rate will be lower with DBT. Purpose To evaluate the benign biopsy rate of DBT versus that of FFDM in women recalled after breast screening within the National Health Service Breast Screening Programme. Materials and Methods This prospective single institution study included women who underwent screening FFDM or screening breast MRI between November 13, 2015, and July 29, 2016, and were recalled. Women who were recalled underwent a breast examination, additional imaging (mammography, US), and biopsy, if required. The number of interventions and the outcome of assessment were recorded. FFDM was performed at the screening appointment, and DBT images were acquired when participants attended a screening assessment within 3 weeks after screening FFDM. Two of four readers blinded to biopsy results analyzed DBT images in isolation and then in conjunction with FFDM images and any additional two-dimensional mammographic or US images. Two-tailed McNemar tests were used to test differences in sensitivity and specificity of the two conditions at 5% significance level. Results During the study period, 30 933 women underwent FFDM. A total of 1470 women were recalled (recall rate, 4.8%), and 827 were included after exclusion criteria were applied. Their mean age was 56.7 years ± 7.7 (standard deviation). A total of 145 breast cancers were detected (142 with FFDM, two with DBT only, one with surveillance MRI). Triple assessment without DBT resulted in 571 breast biopsies and enabled detection of 142 cancers. The addition of DBT would have resulted in 298 biopsies and detection of 142 cancers, reducing the number of biopsies from 571 of 827 (69.0%) to 298 of 827 (36.0%). Conclusion When compared with full-field digital mammography, digital breast tomosynthesis can reduce the benign biopsy rate while maintaining the cancer detection rate. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Skaane in this issue.

Breast cancer risk is increased in the years following false-positive breast cancer screening

Supplemental Digital Content is available in the text.

A small number of studies have investigated breast cancer (BC) risk among women with a history of false-positive recall (FPR) in BC screening, but none of them has used time-to-event analysis while at the same time quantifying the effect of false-negative diagnostic assessment (FNDA). FNDA occurs when screening detects BC, but this BC is missed on diagnostic assessment (DA). As a result of FNDA, screenings that detected cancer are incorrectly classified as FPR. Our study linked data recorded in the Flemish BC screening program (women aged 50–69 years) to data from the national cancer registry. We used Cox proportional hazards models on a retrospective cohort of 298 738 women to assess the association between FPR and subsequent BC, while adjusting for potential confounders. The mean follow-up was 6.9 years. Compared with women without recall, women with a history of FPR were at an increased risk of developing BC [hazard ratio=2.10 (95% confidence interval: 1.92–2.31)]. However, 22% of BC after FPR was due to FNDA. The hazard ratio dropped to 1.69 (95% confidence interval: 1.52–1.87) when FNDA was excluded. Women with FPR have a subsequently increased BC risk compared with women without recall. The risk is higher for women who have a FPR BI-RADS 4 or 5 compared with FPR BI-RADS 3. There is room for improvement of diagnostic assessment: 41% of the excess risk is explained by FNDA after baseline screening.

The impact of compression force and pressure at prevalent screening on subsequent re-attendance in a national screening program

Adherence to screening may indirectly help assess whether a prior screening examination deters women from returning for a subsequent examination. We investigated whether compression force and pressure in mammography were associated with re-attendance among prevalently screened women in the organized breast cancer screening program in Norway. Data on compression force (kg) and pressure (kPa) from women's first screening examination in the program (prevalent screening) and subsequent re-attendance were available for 31,225 women aged 50-68, screened during 2007-2013. Crude re-attendance rates and log-binomial regression models estimating the prevalence ratio of re-attendance were used to identify the association between compression force or pressure and re-attendance two-years later. Age and year at prevalent screening, county of residence, screening result (negative or false positive), breast volume, and breast density were included in analyses. Overall, 27,197 (87.1%) women re-attended the program. Re-attendance was highest for women who received a compression force of 10.0-13.9 kg (87.5%) or pressure of 9.0-17.9 kPa (87.8%) and lowest for those who received a compression force of <10.0 kg (85.0%) or pressure of <9.0 kPa (84.7%). The adjusted prevalence of re-attendance was 3% lower for women who received low compression force (<10.0 kg) and 2% lower for women who received low compression pressure (<9.0 kPa) relative to the reference groups (10.0-13.9 kg and 9.0-17.9 kPa, respectively). Future research related to re-attendance should also include information about women's experience of pain, anxiety and stress, as well as image quality.

The impact of false positive breast cancer screening mammograms on screening retention: A retrospective population cohort study in Alberta, Canada

OBJECTIVES

The impact of false positives on breast cancer screening retention is inconsistent across international studies. We investigate factors associated with screening retention, including false positive screening results, invasiveness of diagnostic procedures, and geographic variation in Alberta, Canada.

METHODS

A total of 213 867 women aged 50-67 years who had an index screen mammogram between July 2006 and June 2008 were evaluated at 30 months post index screen to determine the screening retention rate. The association of screening retention with invasiveness of the diagnostic procedure, time to diagnostic resolution, and region of residence were investigated using multivariable log binomial regression, adjusting for women's age.

RESULTS

Women with false positive screening results were less likely to return for their next recommended screening than those with a true negative result (62.0% vs. 68.7%). Compared to women with normal screening results, the adjusted risk ratios of fail-to-rescreen for women with imaging-only follow-up, needle sampling, and open biopsy were 1.08 (95% CI: 1.05-1.12), 1.72 (95% CI: 1.44-2.07) and 2.29 (95% CI: 2.09-2.50) respectively. Screening retention rates were slightly higher for rural residents than urban residents. Time to diagnostic resolution was not associated with screening retention. Screening retention peaked at one year from the index date of the previous screening.

CONCLUSION

Higher awareness of the strong negative impact that biopsies in the case of a false positive screening have on screening retention is needed. Such awareness can inform intervention strategies to mitigate the impact and improve screening retention rate.

Client and practitioner perspectives on the screening mammography experience

Mammography can be painful and unpleasant, but effective interventions to improve the experience remain scarce. As a first step towards more effective interventions, we aimed to achieve a thorough, contemporary understanding of thoughts, feelings and behaviours which affect and arise from mammography experiences. Research and professional experience suggest that the interaction between client and practitioner may be paramount in determining the quality of a client's experience. Therefore, this study aimed to capture the perspectives of clients and mammography staff from UK breast screening programmes. Thematic analysis of semi-structured qualitative in-depth interviews with 22 clients and 18 staff revealed that clients had positive attitudes to breast screening and mostly low knowledge about potential harms. Staff data indicated that some women attend for breast screening under pressure from others. Pain and coping with it were prominent themes, with wide variations in pain experiences. Clients recognised differences in mammographers' abilities to put them at ease. Staff difficulties included empowering clients within the confines of a taxing technique, and maintaining compassionate care when under strain. Future intervention development should focus on the information and support needs of women prior to the appointment and on effectively training and supporting mammographers to deal with challenging encounters.

A qualitative analysis of staff-client interactions within a breast cancer assessment clinic

OBJECTIVES

Breast screening clients recalled to an assessment clinic experience high levels of anxiety. The culture of the assessment clinic may impact upon client experience, which may influence their future re-engagement in screening. This study aimed to explore the culture of staff-client interactions within a breast cancer assessment clinic.

MATERIALS AND METHODS

Following an ethnographic approach, twenty-three client journeys were observed, followed by semi-structured interviews with the clients. The observation and interview data were analysed to produce research themes, which were then explored within two focus groups to add a practitioner perspective.

RESULTS

Multiple staff-client interaction events were observed over a period of several weeks. Client interview feedback was overwhelmingly positive. Three recurrent and sequential themes emerged: breaking down barriers, preparing the ground and sign-posting. These themes outline the changing focus of staff-client interactions during the client's clinic journey, encompassing how anxieties were expressed by clients, and responded to by practitioners.

CONCLUSION

This study was the first to explore in depth the staff-client interaction culture within a breast assessment clinic using an ethnographic approach. A new perspective on professional values and behaviours has been demonstrated via a model of staff-client interaction. The model documents the process of guiding the client from initial confusion and distress to an enhanced clarity of understanding. A recommendation most likely to have a positive impact on the client experience is the introduction of a client navigator role to guide the clients through what is often a lengthy, stressful and confusing process.

Measurement of breast-tissue x-ray attenuation by spectral mammography: solid lesions

Knowledge of x-ray attenuation is essential for developing and evaluating x-ray imaging technologies. For instance, techniques to distinguish between cysts and solid tumours at mammography screening would be highly desirable to reduce recalls, but the development requires knowledge of the x-ray attenuation for cysts and tumours. We have previously measured the attenuation of cyst fluid using photon-counting spectral mammography. Data on x-ray attenuation for solid breast lesions are available in the literature, but cover a relatively wide range, likely caused by natural spread between samples, random measurement errors, and different experimental conditions. In this study, we have adapted a previously developed spectral method to measure the linear attenuation of solid breast lesions. A total of 56 malignant and 5 benign lesions were included in the study. The samples were placed in a holder that allowed for thickness measurement. Spectral (energy-resolved) images of the samples were acquired and the image signal was mapped to equivalent thicknesses of two known reference materials, which can be used to derive the x-ray attenuation as a function of energy. The spread in equivalent material thicknesses was relatively large between samples, which is likely to be caused mainly by natural variation and only to a minor extent by random measurement errors and sample inhomogeneity. No significant difference in attenuation was found between benign and malignant solid lesions. The separation between cyst-fluid and tumour attenuation was, however, significant, which suggests it may be possible to distinguish cystic from solid breast lesions, and the results lay the groundwork for a clinical trial. In addition, the study adds a relatively large sample set to the published data and may contribute to a reduction in the overall uncertainty in the literature.

Harms of Breast Cancer Screening: Systematic Review to Update the 2009 U.S. Preventive Services Task Force Recommendation

BACKGROUND

In 2009, the U.S. Preventive Services Task Force recommended biennial mammography screening for women aged 50 to 74 years and selective screening for those aged 40 to 49 years.

PURPOSE

To review studies of screening in average-risk women with mammography, magnetic resonance imaging, or ultrasonography that reported on false-positive results, overdiagnosis, anxiety, pain, and radiation exposure.

DATA SOURCES

MEDLINE and Cochrane databases through December 2014.

STUDY SELECTION

English-language systematic reviews, randomized trials, and observational studies of screening.

DATA EXTRACTION

Investigators extracted and confirmed data from studies and dual-rated study quality. Discrepancies were resolved through consensus.

DATA SYNTHESIS

Based on 2 studies of U.S. data, 10-year cumulative rates of false-positive mammography results and biopsies were higher with annual than biennial screening (61% vs. 42% and 7% vs. 5%, respectively) and for women aged 40 to 49 years, those with dense breasts, and those using combination hormone therapy. Twenty-nine studies using different methods reported overdiagnosis rates of 0% to 54%; rates from randomized trials were 11% to 22%. Women with false-positive results reported more anxiety, distress, and breast cancer-specific worry, although results varied across 80 observational studies. Thirty-nine observational studies indicated that some women reported pain during mammography (1% to 77%); of these, 11% to 46% declined future screening. Models estimated 2 to 11 screening-related deaths from radiation-induced cancer per 100,000 women using digital mammography, depending on age and screening interval. Five observational studies of tomosynthesis and mammography indicated increased biopsies but reduced recalls compared with mammography alone.

LIMITATIONS

Studies of overdiagnosis were highly heterogeneous, and estimates varied depending on the analytic approach. Studies of anxiety and pain used different outcome measures. Radiation exposure was based on models.

CONCLUSION

False-positive results are common and are higher for annual screening, younger women, and women with dense breasts. Although overdiagnosis, anxiety, pain, and radiation exposure may cause harm, their effects on individual women are difficult to estimate and vary widely.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality.

Comparison of the diagnostic workup of women referred at non-blinded or blinded double reading in a population-based screening mammography programme in the south of the Netherlands

Background:

To determine whether referred women experience differences in diagnostic workup at non-blinded or blinded double reading of screening mammograms.

Methods:

We included a consecutive series of respectively 42.996 and 44.491 screens, double read either in a non-blinded or blinded manner between 2009 and 2011. This reading strategy was alternated on a monthly basis.

Results:

The overall ultrasound-guided core needle biopsy (CNB) rate and stereotactic CNB (SCNB) rate per 1000 screens were higher at blinded than at non-blinded reading (7.5 vs 6.0, P=0.008 and 8.1 vs 6.6, P=0.009). Among women with benign workup, these rates were higher at blinded reading (2.6 vs 1.4, P<0.001 and 5.9 vs 4.7, P=0.013). The benign biopsy rates were higher at blinded double reading (P<0.001), whereas the positive predictive value of biopsy did not differ (P=0.103).

Conclusions:

Blinded double-reading results in higher overall CNB and SCNB rates than non-blinded double reading, as well as a higher benign biopsy rate.