Predicting the cumulative risk of false-positive mammograms

Long-term psychosocial consequences of false-positive screening mammography: a cohort study with follow-up of 12-14 years in Denmark

OBJECTIVE

To compare the long-term psychosocial consequences of mammography screening among women with breast cancer, normal results and false-positive results.

DESIGN

A matched cohort study with follow-up of 12-14 years.

SETTING

Denmark from 2004 to 2019.

PARTICIPANTS

1170 women who participated in the Danish mammography screening programme in 2004-2005.

INTERVENTION

Mammography screening for women aged 50-69 years.

OUTCOME MEASURES

We assessed the psychosocial consequences with the Consequences Of Screening-Breast Cancer, a condition-specific questionnaire that is psychometrically validated and encompasses 14 psychosocial dimensions.

RESULTS

Across all 14 psychosocial outcomes, women with false-positive results averagely reported higher psychosocial consequences compared with women with normal findings. Mean differences were statistically insignificant except for the existential values scale: 0.61 (95% CI (0.15 to 1.06), p=0.009). Additionally, women with false-positive results and women diagnosed with breast cancer were affected in a dose-response manner, where women diagnosed with breast cancer were more affected than women with false-positive results.

CONCLUSION

Our study suggests that a false-positive mammogram is associated with increased psychosocial consequences 12-14 years after the screening. This study adds to the harms of mammography screening. The findings should be used to inform decision-making among the invited women and political and governmental decisions about mammography screening programmes.

Breast Cancer Risk and Screening Mammography Frequency Among Multiethnic Women

INTRODUCTION

In 2009, the U.S. Preventive Services Task Force updated recommended mammography screening frequency from annual to biennial for average-risk women aged 50-74 years. The association between estimated breast cancer risk and mammography screening frequency was evaluated.

METHODS

A single-center retrospective cohort study was conducted among racially/ethnically diverse women, aged 50-74 years, who underwent screening mammography from 2014 to 2018. Data on age, race/ethnicity, first-degree family history of breast cancer, previous benign breast biopsies, and mammographic density were extracted from the electronic health record to calculate Breast Cancer Surveillance Consortium 5-year risk of invasive breast cancer, with a 5-year risk ≥1.67% defined as high risk. Multivariable analyses were conducted to determine the association between breast cancer risk factors and mammography screening frequency (annual versus biennial). Data were analyzed from 2020 to 2022.

RESULTS

Among 12,929 women with a mean age of 61±6.9 years, 82.7% underwent annual screening mammography, and 30.7% met high-risk criteria for breast cancer. Hispanic women were more likely to screen annually than non-Hispanic Whites (85.0% vs 79.8%, respectively), despite fewer meeting high-risk criteria. In multivariable analyses adjusting for breast cancer risk factors, high- versus low/average-risk women (OR=1.17; 95% CI=1.04, 1.32) and Hispanic versus non-Hispanic White women (OR=1.46; 95% CI=1.29, 1.65) were more likely to undergo annual mammography.

CONCLUSIONS

A majority of women continue to undergo annual screening mammography despite only a minority meeting high-risk criteria, and Hispanic women were more likely to screen annually despite lower overall breast cancer risk. Future studies should focus on the implementation of risk-stratified breast cancer screening strategies.

Cumulative risk of a false-positive screening result: A retrospective cohort study using empirical data from 10 biennial screening rounds in BreastScreen Norway

BACKGROUND

False-positive screening results are an inevitable and commonly recognized disadvantage of mammographic screening. This study estimated the cumulative probability of experiencing a first false-positive screening result in women attending 10 biennial screening rounds in BreastScreen Norway, which targets women aged 50 to 69 years.

METHODS

This retrospective cohort study analyzed screening outcomes from 421,545 women who underwent 1,894,523 screening examinations during 1995-2019. Empirical data were used to calculate the cumulative risk of experiencing a first false-positive screening result and a first false-positive screening result that involved an invasive procedure over 10 screening rounds. Logistic regression was used to evaluate the effect of adjusting for irregular attendance, age at screening, and number of screens attended.

RESULTS

The cumulative risk of experiencing a first false-positive screening result was 18.04% (95% confidence interval [CI], 18.00%-18.07%). It was 5.01% (95% CI, 5.01%-5.02%) for experiencing a false-positive screening result that involved an invasive procedure. Adjusting for irregular attendance or age at screening did not appreciably affect these estimates. After adjustments for the number of screens attended, the cumulative risk of a first false-positive screening result was 18.28% (95% CI, 18.24%-18.32%), and the risk of a false-positive screening result including an invasive procedure was 5.11% (95% CI, 5.11%-5.22%). This suggested that there was minimal bias from dependent censoring.

CONCLUSIONS

Nearly 1 in 5 women will experience a false-positive screening result if they attend 10 biennial screening rounds in BreastScreen Norway. One in 20 will experience a false-positive screening result with an invasive procedure.

LAY SUMMARY

A false-positive screening result occurs when a woman attending mammographic screening is called back for further assessment because of suspicious findings, but the assessment does not detect breast cancer. Further assessment includes additional imaging. Usually, it involves ultrasound, and sometimes, it involves a biopsy. This study has evaluated the chance of experiencing a false-positive screening result among women attending 10 screening examinations over 20 years in BreastScreen Norway. Nearly 1 in 5 women will experience a false-positive screening result over 10 screening rounds. One in 20 women will experience a false-positive screening result involving a biopsy.

Lung Screening Benefits and Challenges: A Review of The Data and Outline for Implementation

Lung cancer is the leading cause of cancer-related deaths worldwide, accounting for almost a fifth of all cancer-related deaths. Annual computed tomographic lung cancer screening (CTLS) detects lung cancer at earlier stages and reduces lung cancer-related mortality among high-risk individuals. Many medical organizations, including the U.S. Preventive Services Task Force, recommend annual CTLS in high-risk populations. However, fewer than 5% of individuals worldwide at high risk for lung cancer have undergone screening. In large part, this is owing to delayed implementation of CTLS in many countries throughout the world. Factors contributing to low uptake in countries with longstanding CTLS endorsement, such as the United States, include lack of patient and clinician awareness of current recommendations in favor of CTLS and clinician concerns about CTLS-related radiation exposure, false-positive results, overdiagnosis, and cost. This review of the literature serves to address these concerns by evaluating the potential risks and benefits of CTLS. Review of key components of a lung screening program, along with an updated shared decision aid, provides guidance for program development and optimization. Review of studies evaluating the population considered "high-risk" is included as this may affect future guidelines within the United States and other countries considering lung screening implementation.

Factors associated with false-positive mammography at first screen in an Asian population

Introduction

False-positive recall is an issue in national screening programmes. The aim of this study is to investigate the recall rate at first screen and to identify potential predictors of false-positive recall in a multi-ethnic Asian population-based breast cancer screening programme.

Methods

Women aged 50–64 years attending screening mammography for the first time (n = 25,318) were included in this study. The associations between potential predictors (sociodemographic, lifestyle and reproductive) and false-positive recall were evaluated using multivariable logistic regression models.

Results

The recall rate was 7.6% (n = 1,923), of which with 93.8% were false-positive. Factors independently associated with higher false-positive recall included Indian ethnicity (odds ratio [95% confidence interval]: 1.52 [1.25 to 1.84]), premenopause (1.23 [1.04 to 1.44]), nulliparity (1.85 [1.57 to 2.17]), recent breast symptoms (1.72 [1.31 to 2.23]) and history of breast lump excision (1.87 [1.53 to 2.26]). Factors associated with lower risk of false-positive recall included older age at screen (0.84 [0.73 to 0.97]) and use of oral contraceptives (0.87 [0.78 to 0.97]). After further adjustment of percent mammographic density, associations with older age at screening (0.97 [0.84 to 1.11]) and menopausal status (1.12 [0.95 to 1.32]) were attenuated and no longer significant.

Conclusion

For every breast cancer identified, 15 women without cancer were subjected to further testing. Efforts to educate Asian women on what it means to be recalled will be useful in reducing unnecessary stress and anxiety.

Multi-Perspective Ultrasound Imaging Technology of the Breast with Cylindrical Motion of Linear Arrays

In this paper, we propose a multi-perspective ultrasound imaging technology with the cylindrical motion of four piezoelectric micromachined ultrasonic transducer (PMUT) rotatable linear arrays. The transducer is configured in a cross shape vertically on the circle with the length of the arrays parallel to the z axis, roughly perpendicular to the chest wall. The transducers surrounded the breast, which achieves non-invasive detection. The electric rotary table drives the PMUT to perform cylindrical scanning. A breast model with a 2 cm mass in the center and six 1-cm superficial masses were used for the experimental analysis. The detection was carried out in a water tank and the working temperature was constant at 32 °C. The breast volume data were acquired by rotating the probe 90° with a 2° interval, which were 256 × 180 A-scan lines. The optimized segmented dynamic focusing technology was used to improve the image quality and data reconstruction was performed. A total of 256 A-scan lines at a constant angle were recombined and 180 A-scan lines were recombined according to the nth element as a dataset, respectively. Combined with ultrasound imaging algorithms, multi-perspective ultrasound imaging was realized including vertical slices, horizontal slices and 3D imaging. The seven masses were detected and the absolute error of the size was approximately 1 mm where even the image of the injection pinhole could be seen. Furthermore, the breast boundary could be seen clearly from the chest wall to the nipple, so the location of the masses was easier to confirm. Therefore, the validity and feasibility of the data reconstruction method and imaging algorithm were verified. It will be beneficial for doctors to be able to comprehensively observe the pathological tissue.

Patient, Radiologist, and Examination Characteristics Affecting Screening Mammography Recall Rates in a Large Academic Practice

OBJECTIVE

The aims of this study were to evaluate patient, radiologist, and examination characteristics affecting screening mammography recall rates in an academic breast imaging practice and to identify modifiable factors that could reduce recall variation.

METHODS

This institutional review board-approved retrospective study included screening mammographic examinations in female patients interpreted by 13 breast imaging specialists at an academic center and two outpatient centers from October 1, 2012, to May 31, 2015. Patient demographics were extracted via electronic medical record. Natural language processing captured breast density, BI-RADS assignment, and current and prior screening examination findings. Radiologists' annual screening volumes, clinical experience, and concentration in breast imaging were calculated. Risk aversion, stress from uncertainty, and malpractice concerns were derived via survey. Univariate and multivariate analyses assessed patient, radiologist, and examination characteristics associated with likelihood of mammography recall. The Pearson product-moment correlation coefficient was used to assess the relationship between cancer detection rate and recall rate.

RESULTS

Overall, 5,678 of 61,198 screening examinations (9.3%) were recalled. In multivariate analysis, patient and radiologist characteristics associated with higher odds of recall included patient's age < 50 years (P < .0001), prior mammographic findings (calcification [P < .0001], mass [P < .0001], higher density category [P < .0001]), baseline examination (P < .0001), annual reading volume < 1,250 examinations (P = .0282), and <10 years of experience (P = .0036). Radiologist's risk aversion, stress from uncertainty, malpractice concerns, and cancer detection rates were not associated with higher recall rates (r = -0.36, P = .23).

CONCLUSIONS

In addition to patient and examination factors, screening recall variations were associated with radiologists' annual reading volume and experience. Interventions targeting radiologist factors (screening volumes, second review of potential recalls) may help reduce unwarranted variation in screening recall.

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.

Factors Associated with False Positive Results on Screening Mammography in a Population of Predominantly Hispanic Women

Background: Potential harms of screening mammography include false positive results, such as recall breast imaging or biopsies.Methods: We recruited women undergoing screening mammography at Columbia University Medical Center in New York, New York. They completed a questionnaire on breast cancer risk factors and permitted access to their medical records. Breast cancer risk status was determined using the Gail model and a family history screener. High risk was defined as a 5-year invasive breast cancer risk of ≥1.67% or eligible for BRCA genetic testing. False positive results were defined as recall breast imaging (BIRADS score of 0, 3, 4, or 5) and/or biopsies that did not yield breast cancer.Results: From November 2014 to October 2015, 2,361 women were enrolled and 2,019 were evaluable, of whom 76% were Hispanic and 10% non-Hispanic white. Fewer Hispanic women met high-risk criteria for breast cancer than non-Hispanic whites (18.0% vs. 68.1%), but Hispanics more frequently engaged in annual screening (71.9% vs. 60.8%). Higher breast density (heterogeneously/extremely dense vs. mostly fat/scattered fibroglandular densities) and more frequent screening (annual vs. biennial) were significantly associated with false positive results [odds ratio (OR), 1.64; 95% confidence interval (CI), 1.32-2.04 and OR, 2.18; 95% CI, 1.70-2.80, respectively].Conclusions: We observed that women who screened more frequently or had higher breast density were at greater risk for false positive results. In addition, Hispanic women were screening more frequently despite having a lower risk of breast cancer compared with whites.Impact: Our results highlight the need for risk-stratified screening to potentially minimize the harms of screening mammography. Cancer Epidemiol Biomarkers Prev; 27(4); 446-53. ©2018 AACR.

Preliminary Results of a New Auxiliary Mechatronic Near-Field Radar System to 3D Mammography for Early Detection of Breast Cancer

Accurate and early detection of breast cancer is of high importance, as it is directly associated with the patients’ overall well-being during treatment and their chances of survival. Uncertainties in current breast imaging methods can potentially cause two main problems: (1) missing newly formed or small tumors; and (2) false alarms, which could be a source of stress for patients. A recent study at the Massachusetts General Hospital (MGH) indicates that using Digital Breast Tomosynthesis (DBT) can reduce the number of false alarms, when compared to conventional mammography. Despite the image quality enhancement DBT provides, the accurate detection of cancerous masses is still limited by low radiological contrast (about 1%) between the fibro-glandular tissue and affected tissue at X-ray frequencies. In a lower frequency region, at microwave frequencies, the contrast is comparatively higher (about 10%) between the aforementioned tissues; yet, microwave imaging suffers from low spatial resolution. This work reviews conventional X-ray breast imaging and describes the preliminary results of a novel near-field radar imaging mechatronic system (NRIMS) that can be fused with the DBT, in a co-registered fashion, to combine the advantages of both modalities. The NRIMS consists of two antipodal Vivaldi antennas, an XY positioner, and an ethanol container, all of which are particularly designed based on the DBT physical specifications. In this paper, the independent performance of the NRIMS is assessed by (1) imaging a bearing ball immersed in sunflower oil and (2) computing the heat Specific Absorption Rate (SAR) due to the electromagnetic power transmitted into the breast. The preliminary results demonstrate that the system is capable of generating images of the ball. Furthermore, the SAR results show that the system complies with the standards set for human trials. As a result, a configuration based on this design might be suitable for use in realistic clinical applications.

The Effect of False-positive Mammograms on Antidepressant and Anxiolytic Initiation

BACKGROUND

Despite reported increases in anxiety following a false-positive mammogram, there is little evidence the effect rises to the clinical level of initiating medication.

OBJECTIVE

To analyze the effect of a false-positive mammogram on antidepressant or anxiolytic initiation and identify subpopulations most at risk.

SUBJECTS

MarketScan commercial and Medicaid claims databases used to identify women ages 40-64 undergoing screening mammography with no prior antidepressant or anxiolytic claims.

RESEARCH DESIGN

Using a retrospective cohort design, we estimated the effects of a false-positive relative to a negative mammogram on the likelihood of initiating antidepressants or anxiolytics using multivariate logistic models estimated separately by insurance type.

RESULTS

At 3 months after a false-positive mammogram, the relative risk (RR) for antidepressant or anxiolytic initiation was 1.19 [95% confidence interval (CI), 1.06-1.31] for the commercially insured and 1.13 (95% CI, 0.96-1.29) in the Medicaid population. In addition, 4 subgroups were at particularly elevated risk: commercially insured women ages 40-49 (RR=1.33; 95% CI, 1.13-1.54) or whose false-positive required multiple tests to resolve (RR=1.37; 95% CI, 1.17-1.57), included a biopsy (RR=1.68; 95% CI, 1.18-2.17), or whose resolution took >1 week (RR=1.21; 95% CI, 1.07-1.34).

CONCLUSIONS

False-positive mammograms were associated with significant increases in antidepressant or anxiolytic imitation among the commercially insured. Follow-up resources may be particularly beneficial for cases taking longer to resolve and involving biopsies or multiple tests. The results highlight the need to resolve false-positives quickly and effectively and to monitor depressive symptoms following a positive result.

Psychological Outcomes After a False Positive Mammogram: Preliminary Evidence for Ethnic Differences Across Time

Adverse psychological consequences of screening mammography are well-documented for women who receive a false positive result. However, little is known about ethnic differences. To address this gap, we examine distress associated with an abnormal mammogram (results-related distress) and perceived lifetime risk of breast cancer (perceived risk) among Latinas and non-Latina White (NLW) women 3 months after receipt of a false positive result. A sample of 28 Latina and 27 NLW women who received an initial abnormal mammogram result and later, a definitive non-cancer diagnosis were recruited for this descriptive, longitudinal study. Women were interviewed twice: within 30 days and 3 months after a false positive result. Questionnaires included standard sociodemographic questions, the Impact of Events Scale-Revised, and two perceived breast cancer risk items. All participants experienced decreased distress 3 months after the initial results. Latinas experienced higher levels of distress, F(1,45) = 4.58, p = 0.04, and had a significant increase in perceived breast cancer risk over time, F(1,45) = 3.99, p = 0.05. Larger population-based studies are necessary to confirm ethnic differences in mental health consequences of false positive results. Given cultural emphases concerning respect for authority figures, healthcare professionals may be particularly helpful in working with Latinas to mitigate distress and clarify accurate perceptions of breast cancer risk through evidence-based practice.

Non-invasive optical estimate of tissue composition to differentiate malignant from benign breast lesions: A pilot study

Several techniques are being investigated as a complement to screening mammography, to reduce its false-positive rate, but results are still insufficient to draw conclusions. This initial study explores time domain diffuse optical imaging as an adjunct method to classify non-invasively malignant vs benign breast lesions. We estimated differences in tissue composition (oxy- and deoxyhemoglobin, lipid, water, collagen) and absorption properties between lesion and average healthy tissue in the same breast applying a perturbative approach to optical images collected at 7 red-near infrared wavelengths (635–1060 nm) from subjects bearing breast lesions. The Discrete AdaBoost procedure, a machine-learning algorithm, was then exploited to classify lesions based on optically derived information (either tissue composition or absorption) and risk factors obtained from patient’s anamnesis (age, body mass index, familiarity, parity, use of oral contraceptives, and use of Tamoxifen). Collagen content, in particular, turned out to be the most important parameter for discrimination. Based on the initial results of this study the proposed method deserves further investigation.

National expenditure for false-positive mammograms and breast cancer overdiagnoses estimated at $4 billion a year

Populationwide mammography screening has been associated with a substantial rise in false-positive mammography findings and breast cancer overdiagnosis. However, there is a lack of current data on the associated costs in the United States. We present costs due to false-positive mammograms and breast cancer overdiagnoses among women ages 40-59, based on expenditure data from a major US health care insurance plan for 702,154 women in the years 2011-13. The average expenditures for each false-positive mammogram, invasive breast cancer, and ductal carcinoma in situ in the twelve months following diagnosis were $852, $51,837 and $12,369, respectively. This translates to a national cost of $4 billion each year. The costs associated with false-positive mammograms and breast cancer overdiagnoses appear to be much higher than previously documented. Screening has the potential to save lives. However, the economic impact of false-positive mammography results and breast cancer overdiagnoses must be considered in the debate about the appropriate populations for screening.

Number and characteristics of breast cancer cases diagnosed in four periods in the screening interval of a biennial population-based screening programme

Objective

To describe the distribution and prognostic tumour characteristics of interval breast cancers diagnosed in four periods after index screen (1-6, 7-12, 13-18 and 19+ months) in a population-based screening programme inviting women aged 50–69 years to biennial screening.

Setting

The Norwegian Breast Cancer Screening Programme (NBCSP)

Methods

In all, 848 interval breast cancer cases were diagnosed in 437,235 screening examinations. The distribution and prognostic tumour characteristics of the interval cancers diagnosed in four periods in the screening interval will be described. Proportions and rates will be compared by χ2-test.

Results

A total of 70% of the interval cancers in the NBCSP were diagnosed in the second year of the interval. Except for tumour size (P = 0.027), we found no evidence of adverse prognostic breast characteristics (grade, lymph node involvement, oestrogen and progesterone receptor positive) in invasive tumours diagnosed during the second versus the first year of the screening interval (Chi square P 0.05 for all). The prognostic characteristics of the tumours did not differ by age groups. It was a decreasing interval cancer rate per 10,000 women-years by age.

Conclusion

The risk of interval cancer increases by time after index screen, and 70% of the interval cancers in the NBCSP were diagnosed in the second year of the interval. Prognostic histological tumour characteristics did not differ by time after index screen, thus mean sojourn time (tumour growth rate) seems important for stating an optimal screening interval in a population-based screening programme.

The Economic and Social Value of an Image Exchange Network: A Case for the Cloud

As the health care environment continually changes, radiologists look to the ACR's Imaging 3.0^® initiative to guide the search for value. By leveraging new technology, a cloud-based image exchange network could provide secure universal access to prior images, which were previously siloed, to facilitate accurate interpretation, improved outcomes, and reduced costs. The breast imaging department represents a viable starting point given the robust data supporting the benefit of access to prior imaging studies, existing infrastructure for image sharing, and the current workflow reliance on prior images. This concept is scalable not only to the remainder of the radiology department but also to the broader medical record.

Cumulative risk of false positive test in relation to breast symptoms in mammography screening: a historical prospective cohort study

Mammography has been found effective as the primary screening test for breast cancer. We estimated the cumulative probability of false positive screening test results with respect to symptom history reported at screen. A historical prospective cohort study was done using individual screening data from 413,611 women aged 50-69 years with 2,627,256 invitations for mammography screening between 1992 and 2012 in Finland. Symptoms (lump, retraction, and secretion) were reported at 56,805 visits, and 48,873 visits resulted in a false positive mammography result. Generalized linear models were used to estimate the probability of at least one false positive test and true positive at screening visits. The estimates were compared among women with and without symptoms history. The estimated cumulative probabilities were 18 and 6 % for false positive and true positive results, respectively. In women with a history of a lump, the cumulative probabilities of false positive test and true positive were 45 and 16 %, respectively, compared to 17 and 5 % with no reported lump. In women with a history of any given symptom, the cumulative probabilities of false positive test and true positive were 38 and 13 %, respectively. Likewise, women with a history of a 'lump and retraction' had the cumulative false positive probability of 56 %. The study showed higher cumulative risk of false positive tests and more cancers detected in women who reported symptoms compared to women who did not report symptoms at screen. The risk varies substantially, depending on symptom types and characteristics. Information on breast symptoms influences the balance of absolute benefits and harms of screening.

Is the false-positive rate in mammography in North America too high?

The practice of investigating pathological abnormalities in the breasts of females who are asymptomatic is primarily employed using X-ray mammography. The importance of breast screening is reflected in the mortality-based benefits observed among females who are found to possess invasive breast carcinoma prior to the manifestation of clinical symptoms. It is estimated that population-based screening constitutes a 17% reduction in the breast cancer mortality rate among females affected by invasive breast carcinoma. In spite of the significant utility that screening confers in those affected by invasive cancer, limitations associated with screening manifest as potential harms affecting individuals who are free of invasive disease. Disease-free and benign tumour-bearing individuals who are subjected to diagnostic work-up following a screening examination constitute a population of cases referred to as false positives (FPs). This article discusses factors contributing to the FP rate in mammography and extends the discussion to an assessment of the consequences associated with FP reporting. We conclude that the mammography FP rate in North America is in excess based upon the observation of overtreatment of in situ lesions and the disproportionate distribution of detriment and benefit among the population of individuals recalled for diagnostic work-up subsequent to screening. To address the excessive incidence of FPs in mammography, we investigate solutions that may be employed to remediate the current status of the FP rate. Subsequently, it can be suggested that improvements in the breast-screening protocol, medical litigation risk, image interpretation software and the implementation of image acquisition modalities that overcome superimposition effects are promising solutions.

Association between Breast Parenchymal Complexity and False-Positive Recall From Digital Mammography Versus Breast Tomosynthesis: Preliminary Investigation in the ACRIN PA 4006 Trial

RATIONALE AND OBJECTIVES

We investigate associations between measures of mammographic parenchymal complexity and false-positive (FP) recall from screening with digital mammography (DM) versus digital breast tomosynthesis (DBT).

MATERIALS AND METHODS

We retrospectively analyzed data from 541 women recruited by the American College of Radiology Imaging Network 4006 trial, designed to evaluate callback and detection rates from screening with DM versus combined DM and DBT. Of these, 68 and 56 were FPs based on DM alone versus the combined DM/DBT readings, respectively. Mammographic complexity was quantified with computerized texture analysis and percent density. Logistic regression was performed to evaluate associations between extracted features and FP recall, after adjusting for age and number of previous benign biopsies. Odds ratios and area under the curve (AUC) of the receiver operating characteristic were used to assess association strength.

RESULTS

For DM, age, previous benign biopsies and texture features of correlation, inverse difference moment, sum average, and sum variance were deemed as significant predictors (P <.05) of FP recall, with an AUC = 0.77. For DBT, age was the only significant predictor of FP recall with AUC = 0.64. Using exploratory receiver operating characteristic thresholds for which no true-positives would be missed, a potential FP reduction of 23.5% and 8.9% was demonstrated, respectively, for DM alone versus DM/DBT.

CONCLUSION

Measures of breast complexity measured on 2D digital mammograms are indicative of the likelihood for FP recall from screening with DM, and could help identify women who could benefit from supplemental screening, including DBT.

Integrating Customer Intimacy Into Radiology to Improve the Patient Perspective: The Case of Breast Cancer Screening

OBJECTIVE

The customer intimacy business model has emerged as a key operational approach for health care organizations as they move toward patient-centered care. The question arises how the customer intimacy approach can be implemented in the clinical setting and whether it can help practitioners address problems and improve quality of care.

CONCLUSION

Breast cancer screening and its emphasis on the patient perspective provides an interesting case study for understanding how the customer intimacy approach can be integrated into radiologic practice to improve the patient experience.

Risk of breast cancer after false-positive results in mammographic screening

Women with false-positive results are commonly referred back to routine screening. Questions remain regarding their long-term outcome of breast cancer. We assessed the risk of screen-detected breast cancer in women with false-positive results. We conducted a joint analysis using individual level data from the population-based screening programs in Copenhagen and Funen in Denmark, Norway, and Spain. Overall, 150,383 screened women from Denmark (1991-2008), 612,138 from Norway (1996-2010), and 1,172,572 from Spain (1990-2006) were included. Poisson regression was used to estimate the relative risk (RR) of screen-detected cancer for women with false-positive versus negative results. We analyzed information from 1,935,093 women 50-69 years who underwent 6,094,515 screening exams. During an average 5.8 years of follow-up, 230,609 (11.9%) women received a false-positive result and 27,849 (1.4%) were diagnosed with screen-detected cancer. The adjusted RR of screen-detected cancer after a false-positive result was 2.01 (95% CI: 1.93-2.09). Women who tested false-positive at first screen had a RR of 1.86 (95% CI: 1.77-1.96), whereas those who tested false-positive at third screening had a RR of 2.42 (95% CI: 2.21-2.64). The RR of breast cancer at the screening test after the false-positive result was 3.95 (95% CI: 3.71-4.21), whereas it decreased to 1.25 (95% CI: 1.17-1.34) three or more screens after the false-positive result. Women with false-positive results had a twofold risk of screen-detected breast cancer compared to women with negative tests. The risk remained significantly higher three or more screens after the false-positive result. The increased risk should be considered when discussing stratified screening strategies.

False positives in breast cancer screening with one-view breast tomosynthesis: An analysis of findings leading to recall, work-up and biopsy rates in the Malmö Breast Tomosynthesis Screening Trial

Objectives

To analyse false positives (FPs) in breast cancer screening with tomosynthesis (BT) vs. mammography (DM).

Methods

The Malmö Breast Tomosynthesis Screening Trial (MBTST) is a prospective population-based study comparing one-view BT to DM in screening. This study is based on the first half of the MBTST population (n = 7,500). Differences in FP recall rate, findings leading to recall, work-up and biopsy rate between cases recalled on BT alone, DM alone and BT+DM were analysed.

Results

The FP recall rate was 1.7 % for BT alone (n = 131), 0.9 % for DM alone (n = 69) and 1.1 % for BT + DM (n = 81). The FP recall rate for BT alone was halved after the initial phase of the trial, stabilising at 1.5 %. BT doubled the recall of stellate distortions compared to DM (n = 64 vs. n = 33). There were fewer fibroadenomas and cysts, and the biopsy rate was slightly lower for FP recalled on BT alone compared to DM alone (15.3 % vs. 27.6 %: p = 0.037 and 33.8 % vs. 36.2 %; p = 0.641, respectively).

Conclusions

FPs increased with BT screening mainly due to the recall of stellate distortions. The FP recall rate was still well within the European guidelines and showed evidence of a learning curve. Characterisation of rounded lesions was improved with BT.

Key Points

• Tomosynthesis screening gave a higher false-positive recall rate than mammography

• There was a decline in the false-positive recall rate for tomosynthesis

• The recall due to stellate distortions simulating malignancy was doubled with tomosynthesis

• Tomosynthesis found more radial and postoperative scar tissue than mammography

• Tomosynthesis is better at characterising rounded lesions

Imaging-based screening: maximizing benefits and minimizing harms

Advanced imaging technologies play a central role in screening asymptomatic patients. However, the balance between imaging-based screening's potential benefits versus risks is sometimes unclear. Radiologists will have to address ongoing concerns, including high false-positive rates, incidental findings outside the organ of interest, overdiagnosis, and potential risks from radiation exposure. In this article, we provide a brief overview of these recurring controversies and suggest the following as areas that radiologists should focus on in order to tip the balance toward more benefits and less harms for patients undergoing imaging-based screening: interpretive variability, abnormal finding thresholds, and personalized, risk-based screening.

Mediators of repeat mammography in two tailored interventions for Iranian women

Background

Many theory-based interventions exist that incorporate theoretical constructs (e.g., self-efficacy, behavioral control) believed to increase the likelihood of mammography. Nonetheless, little work to date has examined if increased screening among women receiving such interventions occurs due to changes in these targeted constructs. The aim of this study is to address this gap in the literature in the context of two interventions for improving regular screening among Iranian women.

Methods

A sample of 176 women over 50 years old in Tehran, Iran were randomly allocated into one of these three conditions: 1) an intervention based on Health Belief Model (HBM); 2) an intervention based on an integration of the HBM and selected constructs from the TPB (TPB); and 3) a control group (CON). Questionnaires were administered before the intervention and after a 6-month follow-up. The Preacher and Hayes method of mediation was used in analytic models.

Results

Changes in susceptibility, self-efficacy, and perceived control appeared to mediate HBM-CON differences in screening. Barriers attenuated the mediating effect of self-efficacy. Changes in barriers and self-efficacy appeared to mediate TPB-CON differences in screening.

Conclusion

This study was successful in identifying which theory-based constructs appear to underlie the effectiveness of HBM- and TPB-based interventions. Specific constructs have been identified that should be targeted in clinical practice to increase mammography practices among Iranian women.

Broadband optical mammography instrument for depth-resolved imaging and local dynamic measurements

We present a continuous-wave instrument for non-invasive diffuse optical imaging of the breast in a parallel-plate transmission geometry. The instrument measures continuous spectra in the wavelength range 650-1000 nm, with an intensity noise level <1.5% and a spatial sampling rate of 5 points/cm in the x- and y-directions. We collect the optical transmission at four locations, one collinear and three offset with respect to the illumination optical fiber, to recover the depth of optical inhomogeneities in the tissue. We imaged a tissue-like, breast shaped, silicone phantom (6 cm thick) with two embedded absorbing structures: a black circle (1.7 cm in diameter) and a black stripe (3 mm wide), designed to mimic a tumor and a blood vessel, respectively. The use of a spatially multiplexed detection scheme allows for the generation of on-axis and off-axis projection images simultaneously, as opposed to requiring multiple scans, thus decreasing scan-time and motion artifacts. This technique localizes detected inhomogeneities in 3D and accurately assigns their depth to within 1 mm in the ideal conditions of otherwise homogeneous tissue-like phantoms. We also measured induced hemodynamic changes in the breast of a healthy human subject at a selected location (no scanning). We applied a cyclic, arterial blood pressure perturbation by alternating inflation (to a pressure of 200 mmHg) and deflation of a pneumatic cuff around the subject's thigh at a frequency of 0.05 Hz, and measured oscillations with amplitudes up to 1 μM and 0.2 μM in the tissue concentrations of oxyhemoglobin and deoxyhemoglobin, respectively. These hemodynamic oscillations provide information about the vascular structure and functional integrity in tissue, and may be used to assess healthy or abnormal perfusion in a clinical setting.

Statistical Methods for Estimating the Cumulative Risk of Screening Mammography Outcomes

BACKGROUND

This study illustrates alternative statistical methods for estimating cumulative risk of screening mammography outcomes in longitudinal studies.

METHODS

Data from the US Breast Cancer Surveillance Consortium (BCSC) and the Nijmegen Breast Cancer Screening Program in the Netherlands were used to compare four statistical approaches to estimating cumulative risk. We estimated cumulative risk of false-positive recall and screen-detected cancer after 10 screening rounds using data from 242,835 women ages 40 to 74 years screened at the BCSC facilities in 1993-2012 and from 17,297 women ages 50 to 74 years screened in Nijmegen in 1990-2012.

RESULTS

In the BCSC cohort, a censoring bias model estimated bounds of 53.8% to 59.3% for false-positive recall and 2.4% to 7.6% for screen-detected cancer, assuming 10% increased or decreased risk among women screened for one additional round. In the Nijmegen cohort, false-positive recall appeared to be associated with subsequent discontinuation of screening leading to overestimation of risk of a false-positive recall based on adjusted discrete-time survival models. Bounds estimated by the censoring bias model were 11.0% to 19.9% for false-positive recall and 4.2% to 9.7% for screen-detected cancer.

CONCLUSION

Choice of statistical methodology can substantially affect cumulative risk estimates. The censoring bias model is appropriate under a variety of censoring mechanisms and provides bounds for cumulative risk estimates under varying degrees of dependent censoring.

IMPACT

This article illustrates statistical methods for estimating cumulative risks of cancer screening outcomes, which will be increasingly important as screening test recommendations proliferate.

Towards personalized screening: Cumulative risk of breast cancer screening outcomes in women with and without a first-degree relative with a history of breast cancer

Several reviews have estimated the balance of benefits and harms of mammographic screening in the general population. The balance may, however, differ between individuals with and without family history. Therefore, our aim is to assess the cumulative risk of screening outcomes; screen-detected breast cancer, interval cancer, and false-positive results, in women screenees aged 50-75 and 40-75, with and without a first-degree relative with a history of breast cancer at the start of screening. Data on screening attendance, recall and breast cancer detection were collected for each woman living in Nijmegen (The Netherlands) since 1975. We used a discrete time survival model to calculate the cumulative probability of each major screening outcome over 19 screening rounds. Women with a family history of breast cancer had a higher risk of all screening outcomes. For women screened from age 50-75, the cumulative risk of screen-detected breast cancer, interval cancer and false-positive results were 9.0, 4.4 and 11.1% for women with a family history and 6.3, 2.7 and 7.3% for women without a family history, respectively. The results for women 40-75 followed the same pattern for women screened 50-75 for cancer outcomes, but were almost doubled for false-positive results. To conclude, women with a first-degree relative with a history of breast cancer are more likely to experience benefits and harms of screening than women without a family history. To complete the balance and provide risk-based screening recommendations, the breast cancer mortality reduction and overdiagnosis should be estimated for family history subgroups.

Doctor, what does my positive test mean? From Bayesian textbook tasks to personalized risk communication

Most of the research on Bayesian reasoning aims to answer theoretical questions about the extent to which people are able to update their beliefs according to Bayes' Theorem, about the evolutionary nature of Bayesian inference, or about the role of cognitive abilities in Bayesian inference. Few studies aim to answer practical, mainly health-related questions, such as, "What does it mean to have a positive test in a context of cancer screening?" or "What is the best way to communicate a medical test result so a patient will understand it?". This type of research aims to translate empirical findings into effective ways of providing risk information. In addition, the applied research often adopts the paradigms and methods of the theoretically-motivated research. But sometimes it works the other way around, and the theoretical research borrows the importance of the practical question in the medical context. The study of Bayesian reasoning is relevant to risk communication in that, to be as useful as possible, applied research should employ specifically tailored methods and contexts specific to the recipients of the risk information. In this paper, we concentrate on the communication of the result of medical tests and outline the epidemiological and test parameters that affect the predictive power of a test-whether it is correct or not. Building on this, we draw up recommendations for better practice to convey the results of medical tests that could inform health policy makers (What are the drawbacks of mass screenings?), be used by health practitioners and, in turn, help patients to make better and more informed decisions.

Racial differences in false-positive mammogram rates: results from the ACRIN Digital Mammographic Imaging Screening Trial (DMIST)

BACKGROUND

Mammography screening reduces breast cancer mortality, but false-positive tests are common. Few studies have assessed racial differences in false-positive rates.

OBJECTIVES

We compared false-positive mammography rates for black and white women, and the effect of patient and facility characteristics on false positives.

RESEARCH DESIGN AND SUBJECTS

A prospective cohort study. From a sample of the American College of Radiology Imaging Network (ACRIN) Digital Mammographic Imaging Screening Trial (DMIST), we identified black/African American (N=3176) or white (N=26,446) women with no prior breast surgery or breast cancer.

MEASURES

Race, demographics, and breast cancer risk factors were self-reported. Results of initial digital and film mammograms were assessed. False positives were defined as a positive mammogram (Breast Imaging Reporting and Data System category 0, 4, 5) with no cancer diagnosis within 15 months.

RESULTS

The false-positive rate for digital mammograms was 9.2% for black women compared with 7.8% for white women (P=0.009). After adjusting for age, black women had 17% increased odds of false-positive digital mammogram compared with whites (OR=1.17; 95% CI, 1.01-1.35; P=0.033). This association was attenuated after adjusting for patient factors, prior films, and study site (OR=1.04; 95% CI, 0.91-1.20; P=0.561). There was no difference in the occurrence of false positives by race for film mammography.

CONCLUSIONS

Black women had higher frequency of false-positive digital mammograms explained by lack of prior films and study site.The variation in the disparity between the established technique (film) and the new technology (digital) raises the possibility that racial differences in screening quality may be greatest for new technologies.

Bioregulation

During the 20th century great progress was made in genetics and biochemistry, and these were combined into a molecular biological understanding of functions of macromolecules. Further great discoveries will be made about bioregulations, applicable to scientific problems such as cell development and evolution, and to illnesses including heart disease through defective control of cholesterol production, and to neurological cell-based diseases. The "War Against Cancer" is still far from won. The present generation of scientists can develop clinical applications from recent basic science discoveries.

Comparison of cumulative false-positive risk of screening mammography in the United States and Denmark

INTRODUCTION

In the United States (US), about one-half of women screened with annual mammography have at least one false-positive test after ten screens. The estimate for European women screened ten times biennially is much lower. We evaluate to what extent screening interval, mammogram type, and statistical methods, can explain the reported differences.

METHODS

We included all screens from women first screened at age 50-69 years in the US Breast Cancer Surveillance Consortium (BCSC) (n=99,455) between 1996-2010, and from two population-based mammography screening programs in Denmark (n=230,452 and n=400,204), between 1991-2012 and 1993-2013, respectively. Model-based cumulative false-positive risks were computed for the entire sample, using two statistical methods (Hubbard Njor) previously used to estimate false-positive risks in the US and Europe.

RESULTS

Empirical cumulative risk of at least one false-positive test after eight (annual or biennial) screens was 41.9% in BCSC, 16.1% in Copenhagen, and 7.4% in Funen. Variation in screening interval and mammogram type did not explain the differences by country. Using the Hubbard method, the model-based cumulative risks after eight screens was 45.1% in BCSC, 9.6% in Copenhagen, and 8.8% in Funen. Using the Njor method, these risks were estimated to be 43.6, 10.9 and 8.0%.

CONCLUSION

Choice of statistical method, screening interval and mammogram type does not explain the substantial differences in cumulative false-positive risk between the US and Europe.

Breast cancer screening: an evidence-based update

Routine screening mammography is recommended by most groups issuing breast cancer screening guidelines, especially for women 50 years of age and older. However, both the potential benefits and risks of screening should be discussed with individual patients to allow for shared decision making regarding their participation in screening, age of commencement and conclusion, and interval of mammography screening.

Consequences of false-positive screening mammograms

IMPORTANCE

False-positive mammograms, a common occurrence in breast cancer screening programs, represent a potential screening harm that is currently being evaluated by the US Preventive Services Task Force.

OBJECTIVE

To measure the effect of false-positive mammograms on quality of life by measuring personal anxiety, health utility, and attitudes toward future screening.

DESIGN, SETTING, AND PARTICIPANTS

The Digital Mammographic Imaging Screening Trial (DMIST) quality-of-life substudy telephone survey was performed shortly after screening and 1 year later at 22 DMIST sites and included randomly selected DMIST participants with positive and negative mammograms.

EXPOSURE

Mammogram requiring follow-up testing or referral without a cancer diagnosis.

MAIN OUTCOMES AND MEASURES

The 6-question short form of the Spielberger State-Trait Anxiety Inventory state scale (STAI-6) and the EuroQol EQ-5D instrument with US scoring. Attitudes toward future screening as measured by women's self-report of future intention to undergo mammographic screening and willingness to travel and stay overnight to undergo a hypothetical new type of mammography that would identify as many cancers with half the false-positive results.

RESULTS

Among 1450 eligible women invited to participate, 1226 (84.6%) were enrolled, with follow-up interviews obtained in 1028 (83.8%). Anxiety was significantly higher for women with false-positive mammograms (STAI-6, 35.2 vs 32.7), but health utility scores did not differ and there were no significant differences between groups at 1 year. Future screening intentions differed by group (25.7% vs 14.2% more likely in false-positive vs negative groups); willingness to travel and stay overnight did not (9.9% vs 10.5% in false-positive vs negative groups). Future screening intention was significantly increased among women with false-positive mammograms (odds ratio, 2.12; 95% CI, 1.54-2.93), younger age (2.78; 1.5-5.0), and poorer health (1.63; 1.09-2.43). Women's anticipated high-level anxiety regarding future false-positive mammograms was associated with willingness to travel overnight (odds ratio, 1.94; 95% CI, 1.28-2.95).

CONCLUSIONS AND RELEVANCE

False-positive mammograms were associated with increased short-term anxiety but not long-term anxiety, and there was no measurable health utility decrement. False-positive mammograms increased women's intention to undergo future breast cancer screening and did not increase their stated willingness to travel to avoid a false-positive result. Our finding of time-limited harm after false-positive screening mammograms is relevant for clinicians who counsel women on mammographic screening and for screening guideline development groups.

The cumulative risk of false-positive results in the Norwegian Breast Cancer Screening Program: updated results

BACKGROUND

Some false-positive results are inevitable in mammographic screening, but the impact of false-positive findings on the program and the participants is a disadvantage of screening. The objective of the current study was to estimate the cumulative risk of a false-positive result over 10 biennial screening examinations and the cumulative risk of undergoing an invasive procedure with a benign outcome in women screened between the ages of 50 years to 69 years.

METHODS

A retrospective cohort study was performed in 231,310 women aged 50 years to 51 years at the time of first mammography screening who underwent 715,311 screening mammograms in the Norwegian Breast Cancer Screening Program from 1996 through 2010. Generalized linear mixed models were used to estimate the probability of a false-positive screening result and to compute the cumulative false-positive risk for up to 10 biennial screening examinations.

RESULTS

The cumulative false-positive risk after 20 years of biennial screening for women who initiated screening aged 50 years to 51 years was 20.0% (95% confidence interval [95% CI], 19.7%-20.4%). The cumulative risk of undergoing an invasive procedure with a benign outcome for the same group of women was 4.1% (95% CI, 3.9%-4.3%). The cumulative risk of undergoing a fine-needle aspiration cytology, core needle biopsy, or open biopsy with a benign outcome was 1.4% (95% CI, 1.3%-1.5%), 2.0% (95% CI, 1.9%-2.1%), and 0.16% (95% CI, 0.13%-0.19%), respectively.

CONCLUSIONS

One in every 5 women will be recalled for further assessment with a negative outcome if they attend biennial mammographic screening between ages 50 years to 69 years. The risk of an invasive procedure with a benign outcome is approximately 4%. It is important to communicate the existence and extent of this risk to the target group and to reduce to a minimum the waiting times between screening and further assessment.

Screening for breast cancer with mammography

BACKGROUND

A variety of estimates of the benefits and harms of mammographic screening for breast cancer have been published and national policies vary.

OBJECTIVES

To assess the effect of screening for breast cancer with mammography on mortality and morbidity.

SEARCH METHODS

We searched PubMed (22 November 2012) and the World Health Organization's International Clinical Trials Registry Platform (22 November 2012).

SELECTION CRITERIA

Randomised trials comparing mammographic screening with no mammographic screening.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data. Study authors were contacted for additional information.

MAIN RESULTS

Eight eligible trials were identified. We excluded a trial because the randomisation had failed to produce comparable groups.The eligible trials included 600,000 women in the analyses in the age range 39 to 74 years. Three trials with adequate randomisation did not show a statistically significant reduction in breast cancer mortality at 13 years (relative risk (RR) 0.90, 95% confidence interval (CI) 0.79 to 1.02); four trials with suboptimal randomisation showed a significant reduction in breast cancer mortality with an RR of 0.75 (95% CI 0.67 to 0.83). The RR for all seven trials combined was 0.81 (95% CI 0.74 to 0.87). We found that breast cancer mortality was an unreliable outcome that was biased in favour of screening, mainly because of differential misclassification of cause of death. The trials with adequate randomisation did not find an effect of screening on total cancer mortality, including breast cancer, after 10 years (RR 1.02, 95% CI 0.95 to 1.10) or on all-cause mortality after 13 years (RR 0.99, 95% CI 0.95 to 1.03).Total numbers of lumpectomies and mastectomies were significantly larger in the screened groups (RR 1.31, 95% CI 1.22 to 1.42), as were number of mastectomies (RR 1.20, 95% CI 1.08 to 1.32). The use of radiotherapy was similarly increased whereas there was no difference in the use of chemotherapy (data available in only two trials).

AUTHORS' CONCLUSIONS

If we assume that screening reduces breast cancer mortality by 15% and that overdiagnosis and overtreatment is at 30%, it means that for every 2000 women invited for screening throughout 10 years, one will avoid dying of breast cancer and 10 healthy women, who would not have been diagnosed if there had not been screening, will be treated unnecessarily. Furthermore, more than 200 women will experience important psychological distress including anxiety and uncertainty for years because of false positive findings. To help ensure that the women are fully informed before they decide whether or not to attend screening, we have written an evidence-based leaflet for lay people that is available in several languages on www.cochrane.dk. Because of substantial advances in treatment and greater breast cancer awareness since the trials were carried out, it is likely that the absolute effect of screening today is smaller than in the trials. Recent observational studies show more overdiagnosis than in the trials and very little or no reduction in the incidence of advanced cancers with screening.

Long-term psychosocial consequences of false-positive screening mammography

PURPOSE

Cancer screening programs have the potential of intended beneficial effects, but they also inevitably have unintended harmful effects. In the case of screening mammography, the most frequent harm is a false-positive result. Prior efforts to measure their psychosocial consequences have been limited by short-term follow-up, the use of generic survey instruments, and the lack of a relevant benchmark-women with breast cancer.

METHODS

In this cohort study with a 3-year follow-up, we recruited 454 women with abnormal findings in screening mammography over a 1-year period. For each woman with an abnormal finding on a screening mammogram (false and true positives), we recruited another 2 women with normal screening results who were screened the same day at the same clinic. These participants were asked to complete the Consequences of Screening in Breast Cancer-a validated questionnaire encompassing 12 psychosocial outcomes-at baseline, 1, 6, 18, and 36 months.

RESULTS

Six months after final diagnosis, women with false-positive findings reported changes in existential values and inner calmness as great as those reported by women with a diagnosis of breast cancer (Δ = 1.15; P = .015; and Δ = 0.13; P = .423, respectively). Three years after being declared free of cancer, women with false-positive results consistently reported greater negative psychosocial consequences compared with women who had normal findings in all 12 psychosocial outcomes (Δ >0 for 12 of 12 outcomes; P <.01 for 4 of 12 outcomes).

CONCLUSION

False-positive findings on screening mammography causes long-term psychosocial harm: 3 years after a false-positive finding, women experience psychosocial consequences that range between those experienced by women with a normal mammogram and those with a diagnosis of breast cancer.

A semiparametric censoring bias model for estimating the cumulative risk of a false-positive screening test under dependent censoring

False-positive test results are among the most common harms of screening tests and may lead to more invasive and expensive diagnostic testing procedures. Estimating the cumulative risk of a false-positive screening test result after repeat screening rounds is, therefore, important for evaluating potential screening regimens. Existing estimators of the cumulative false-positive risk are limited by strong assumptions about censoring mechanisms and parametric assumptions about variation in risk across screening rounds. To address these limitations, we propose a semiparametric censoring bias model for cumulative false-positive risk that allows for dependent censoring without specifying a fixed functional form for variation in risk across screening rounds. Simulation studies demonstrated that the censoring bias model performs similarly to existing models under independent censoring and can largely eliminate bias under dependent censoring. We used the existing and newly proposed models to estimate the cumulative false-positive risk and variation in risk as a function of baseline age and family history of breast cancer after 10 years of annual screening mammography using data from the Breast Cancer Surveillance Consortium. Ignoring potential dependent censoring in this context leads to underestimation of the cumulative risk of false-positive results. Models that provide accurate estimates under dependent censoring are critical for providing appropriate information for evaluating screening tests.

False-positive screening mammograms and biopsies among women participating in a Canadian provincial breast screening program

BACKGROUND

Mammography screening results in false positives that cause anxiety and utilize scarce medical resources for their resolution. Determination of screening recommendations requires knowledge of the population risk of false positives.

METHODS

Data were extracted from the Screening Mammography Program of British Columbia and analyzed to determine the influence of personal factors including age, ethnic group and screening history, and the centre where screening was performed, on the likelihood a new screen would result in a false positive and whether a biopsy was required. The resulting probabilities were combined to provide values for lifetime screening algorithms.

RESULTS

Age, screen sequence number, history of previous abnormal screens and centre where screening was performed were significantly related to the likelihood a new screen would be a false positive. British Columbia women screened biennially between the ages of 50 and 69 have a projected 41% chance of a false-positive screen and a 5.6% risk of a related biopsy, with the best performing centres having rates of 26% and 3%, respectively.

INTERPRETATION

Model projections for BC overall are comparable to other North American estimates. Estimates varied depending upon screening centre attended.

A molecular computational model improves the preoperative diagnosis of thyroid nodules

Background

Thyroid nodules with indeterminate cytological features on fine needle aspiration (FNA) cytology have a 20% risk of thyroid cancer. The aim of the current study was to determine the diagnostic utility of an 8-gene assay to distinguish benign from malignant thyroid neoplasm.

Methods

The mRNA expression level of 9 genes (KIT, SYNGR2, C21orf4, Hs.296031, DDI2, CDH1, LSM7, TC1, NATH) was analysed by quantitative PCR (q-PCR) in 93 FNA cytological samples. To evaluate the diagnostic utility of all the genes analysed, we assessed the area under the curve (AUC) for each gene individually and in combination. BRAF exon 15 status was determined by pyrosequencing. An 8-gene computational model (Neural Network Bayesian Classifier) was built and a multiple-variable analysis was then performed to assess the correlation between the markers.

Results

The AUC for each significant marker ranged between 0.625 and 0.900, thus all the significant markers, alone and in combination, can be used to distinguish between malignant and benign FNA samples. The classifier made up of KIT, CDH1, LSM7, C21orf4, DDI2, TC1, Hs.296031 and BRAF had a predictive power of 88.8%. It proved to be useful for risk stratification of the most critical cytological group of the indeterminate lesions for which there is the greatest need of accurate diagnostic markers.

Conclusion

The genetic classification obtained with this model is highly accurate at differentiating malignant from benign thyroid lesions and might be a useful adjunct in the preoperative management of patients with thyroid nodules.

Risk of breast cancer after false-positive test results in screening mammography

BACKGROUND

Screening for disease in healthy people inevitably leads to some false-positive tests in disease-free individuals. Normally, women with false-positive screening tests for breast cancer are referred back to routine screening. However, the long-term outcome for women with false-positive tests is unknown.

METHODS

We used data from a long-standing population-based screening mammography program in Copenhagen, Denmark, to determine the long-term risk of breast cancer in women with false-positive tests. The age-adjusted relative risk (RR) of breast cancer for women with a false-positive test compared with women with only negative tests was estimated with Poisson regression, adjusted for age, and stratified by screening round and technology period. All statistical tests were two-sided.

RESULTS

A total of 58 003 women, aged 50-69 years, were included in the analysis. Women with negative tests had an absolute cancer rate of 339/100 000 person-years at risk, whereas women with a false-positive test had an absolute rate of 583/100 000 person-years at risk. The adjusted relative risk of breast cancer after a false-positive test was 1.67 (95% confidence interval [CI] 1.45 to 1.88). The relative risk remained statistically significantly increased 6 or more years after the false-positive test, with point estimates varying between 1.58 and 2.30. When stratified by assessment technology phase and using equal follow-up time, the false-positive group from the mid 1990s had a statistically significantly higher risk of breast cancer (RR = 1.65, 95% CI = 1.22 to 2.24) than the group with negative tests, whereas the false-positive group from the early 2000s was not statistically significantly different from the group testing negative.

CONCLUSIONS

The implementation of new assessment technology coincided with a decrease in the size of excess risk of breast cancer for women with false-positive screening results. However, it may be beneficial to actively encourage women with false-positive tests to continue to attend regular screening.

Effect of protocol-related variables and women's characteristics on the cumulative false-positive risk in breast cancer screening

BACKGROUND

Reducing the false-positive risk in breast cancer screening is important. We examined how the screening-protocol and women's characteristics affect the cumulative false-positive risk.

METHODS

This is a retrospective cohort study of 1,565,364 women aged 45-69 years who underwent 4,739,498 screening mammograms from 1990 to 2006. Multilevel discrete hazard models were used to estimate the cumulative false-positive risk over 10 sequential mammograms under different risk scenarios.

RESULTS

The factors affecting the false-positive risk for any procedure and for invasive procedures were double mammogram reading [odds ratio (OR)=2.06 and 4.44, respectively], two mammographic views (OR=0.77 and 1.56, respectively), digital mammography (OR=0.83 for invasive procedures), premenopausal status (OR=1.31 and 1.22, respectively), use of hormone replacement therapy (OR=1.03 and 0.84, respectively), previous invasive procedures (OR=1.52 and 2.00, respectively), and a familial history of breast cancer (OR=1.18 and 1.21, respectively). The cumulative false-positive risk for women who started screening at age 50-51 was 20.39% [95% confidence interval (CI) 20.02-20.76], ranging from 51.43% to 7.47% in the highest and lowest risk profiles, respectively. The cumulative risk for invasive procedures was 1.76% (95% CI 1.66-1.87), ranging from 12.02% to 1.58%.

CONCLUSIONS

The cumulative false-positive risk varied widely depending on the factors studied. These findings are relevant to provide women with accurate information and to improve the effectiveness of screening programs.

Prediction of higher mortality reduction for the UK Breast Screening Frequency Trial: a model-based approach on screening intervals

Background:

The optimal interval between two consecutive mammograms is uncertain. The UK Frequency Trial did not show a significant difference in breast cancer mortality between screening every year (study group) and screening every 3 years (control group). In this study, the trial is simulated in order to gain insight into the results of the trial and to predict the effect of different screening intervals on breast cancer mortality.

Methods:

UK incidence, life tables and information from the trial were used in the microsimulation model MISCAN–Fadia to simulate the trial and predict the number of breast cancer deaths in each group. To be able to replicate the trial, a relatively low sensitivity had to be assumed.

Results:

The model simulated a larger difference in tumour size distribution between the two groups than observed and a relative risk (RR) of 0.83 of dying from breast cancer in the study group compared with the control group. The predicted RR is lower than that reported from the trial (RR 0.93), but within its 95% confidence interval (0.63–1.37).

Conclusion:

The present study suggests that there is benefit of shortening the screening interval, although the benefit is probably not large enough to start annual screening.

Effect of start age of breast cancer screening mammography on the risk of false-positive results

OBJECTIVE

To estimate the false-positive (FP) risk according to the start age of mammography screening (45-46 or 50-51 years).

METHOD

Data from eight regions of the Spanish breast cancer screening programme from 1990 to 2006 were included (1,565,364 women). Discrete time-hazard models were used to ascertain the effect of age and time-related, programme-related and personal variables on FP leading to any further procedure and to invasive procedures (FPI). In a subset we estimated the differential FP risk of starting screening at 45-46 years (175,656 women) or 50-51 (251,275).

RESULTS

A start age of 45-46 versus 50-51 years increased both FP (OR=1.20; 95%CI: 1.13-1.26) and FPI risks (OR=1.43 (95%CI: 1.18-1.73).Other factors increasing FP risk were premenopausal status (FP OR=1.26; 95%CI: 1.23-1.29 and FPI OR=1.22; 95%CI: 1.13-1.31), prior invasive procedures (FP OR=1.52; 95%CI: 1.47-1.57 and FPI (OR=2.08; 95%CI: 1.89-2.28) and family history (FP OR=1.16; 95%CI: 1.12-1.20 and FPI OR=1.26; 95%CI: 1.13-1.41). FP risk was increased by double reading (OR=1.36; 95%CI: 1.23-1.51) and FPI risk by double views (OR=1.34; 95%CI: 1.18-1.52). Both the cumulative FP and FPI risks were higher in women commencing screening at 45-46 years versus 50-51 years (33.30% versus 20.39% and 2.68% versus 1.76%).

CONCLUSIONS

Starting screening earlier increases the cumulative risk of FP and FPI.