Average Risk For Breast Cancer Research Articles

Abstract PO-248: Breast cancer risk factors, prevalence, and screening rates in uninsured women seen at free clinics

Abstract Introduction: Uninsured women face increased barriers to obtaining age appropriate breast cancer screening. Despite the National Breast and Cervical Cancer Early Detection Program which provides breast cancer screening services to uninsured women below the federal poverty level, a majority of uninsured women still do not receive screenings. As a result, uninsured women are at risk of presenting with more advanced cancer. The purpose of this study is to identify risk factors, prevalence, and screening rates for breast cancer among uninsured women seen at free clinics. Methods: A retrospective chart review was conducted to collect demographics, risk factors, breast cancer prevalence, and screening rates from medical records at ten free clinics in the Tampa Bay area of Florida from January 1st 2016-December 31st 2018. Uninsured women above the age of 45 were included in the study, in accordance with the American Cancer Society’s recommendation to begin screening women of average breast cancer risk by that age. Results: A total of 3721 women over the age of 45 were seen at free clinics during the study period. The mean age was 56.0 (SD=7.8). This sample was largely composed of Hispanic (n=1466, 47.6%) and unemployed (n=845, 46.2%) women. The mean (SD) BMI of patients was 30.5 (7.8). Of those with a recorded substance use history, 433 (18.7%) were current smokers and 454 (24.3%) were current alcohol consumers. Mammograms were documented for 838 (22.5%) of patients above the age of 45 years. The prevalence of breast cancer was 2.0% (n=73). Conclusions: Our study identifies a population of uninsured women who are at risk for breast cancer based on specific risk factors including age, BMI, smoking history, and alcohol use. Uninsured women seen at free clinics have suboptimal breast cancer screening rates. Our study population is largely comprised of Hispanic, unemployed, and low-income women who face additional healthcare barriers putting them at risk of advanced stage breast cancer. Our study increases awareness of an at-risk population, and increased efforts need to be made to provide uninsured women with age appropriate breast cancer screening in order to reduce morbidity and mortality. Citation Format: Madeline MacDonald, Justin Swanson, Shreni Shah, Jhulianna Vivar, Ethan Song, Tanzila Ahsan, Rahul Mhaskar, Abu-Sayeef Mirza. Breast cancer risk factors, prevalence, and screening rates in uninsured women seen at free clinics [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-248.

Risk stratification in breast cancer screening: Cost-effectiveness and harm-benefit ratios for low-risk and high-risk women.

In mammography screening programmes, women are screened according to a one-size-fits-all principle. Tailored screening, based on risk levels, may lead to a better balance of benefits and harms. With microsimulation modelling, we determined optimal mammography screening strategies for women at lower (relative risk [RR] 0.75) and higher (RR 1.8) than average risk of breast cancer, eligible for screening, using the incremental cost-effectiveness ratio (ICER) of current uniform screening in the Netherlands (biennial [B] 50-74) as a threshold ICER. Strategies varied by interval (annual [A], biennial, triennial [T]) and age range. The number of life-years gained (LYG), breast cancer deaths averted, overdiagnosed cases, false-positive mammograms, ICERs and harm-benefit ratios were calculated. Optimal risk-based screening scenarios, below the threshold ICER of €8883/LYG, were T50-71 (€7840/LYG) for low-risk and B40-74 (€6062/LYG) for high-risk women. T50-71 screening in low-risk women resulted in a 33% reduction in false-positive findings, a similar reduction in costs and improved harm-benefit ratios compared to the current screening schedule. B40-74 in high-risk women led to an increase in screening benefit, compared to current B50-74 screening, but a relatively higher increase in false-positive findings. In conclusion, optimal screening consisted of a longer interval and lower stopping age than current uniform screening for low-risk women, and a lower starting age for high-risk women. Extending the interval for women at lower risk from biennial to triennial screening reduced harms and costs while maintaining most of the screening benefit.

Current Guidelines and Gaps in Breast Cancer Screening.

Breast cancer is the most common nonskin cancer in women and the second leading cause of cancer death for women in the United States. Mammography screening is proven to significantly decrease breast cancer mortality, with a 40% or more reduction expected with annual use starting at age 40 for women of average risk. However, less than half of all eligible women have a mammogram annually. The elimination of cost sharing for screening made possible by the Affordable Care Act (2010) encouraged screening but mainly for those already insured. The United States Preventive Services Task Force 2009 guidelines recommended against screening those 40 to 49 years old and have left women over 74 years of age vulnerable to coverage loss. Other populations for whom significant gaps in risk information or screening use exist, including women of lower socioeconomic status, black women, men at higher than average risk of breast cancer, and sexual and gender minorities. Further work is needed to achieve higher rates of screening acceptance for all appropriate individuals so that the full mortality and treatment benefits of mammography screening can be realized.

Epigenetic control of breast cancer susceptibility.

1560 Background: Epigenetic mechanisms such as DNA methylation are important regulators of gene expression and are frequently dysregulated early in breast carcinogenesis. The relationship between DNA methylation aberrations in normal breast tissue and breast cancer risk remains unclear. Methods: Disease-free breast tissue cores donated by 71 high-risk (Tyrer-Cuzick lifetime risk ≥20%) and 79 average-risk women were obtained from the Komen Tissue Bank and processed for whole methylome (Diagenode's MethylCap Library and single-end 75-bp sequencing on Illumina Nextseq) and whole transcriptome (Illumina Nextseq) profiling. Reads from RNA-seq data were aligned to the human genome reference, GRCh38.p12 using STAR v.2.5.2b and tested for differential gene expression using DESeq2 ver. 1.24.0. For DNA methylation data, difference of variation in deduplicated read coverage among 250-bp fixed sized bins spanning CpG islands between high- and average-risk libraries was computed as z-ratios to identify differentially methylated regions. Pathway analysis was performed using IPA v06_01. Results: We identified 1355 CpGs that were differentially methylated between high- and average-risk breast tissues (ΔZ > 0.5, FDR < 0.05). Hypomethylated CpGs were overrepresented in high-risk tissue and were found predominantly (68%) in non-coding regions. Hypermethylated CpG sites were found equally in the gene body and non-coding regions. Transcriptomic analysis identified 112 differentially expressed genes (fold change≥2, FDR < 0.05), involved in chemokines signaling, metabolism and estrogen biosynthesis. Among those, FAM83A (logfc = 2.3, FDR = 0.004) was previously described as epigenetically dysregulated in multiple cancers and transforms breast epithelial cell in vitro. Methylation-expression correlations revealed 11 epigenetically regulated genes including cellular transformation-associated BMPR1B. Two hypomethylated/upregulated long non-coding RNAs were also identified in high-risk breasts. Conclusions: This is the first gene expression/DNA methylation analysis of normal breasts from women at either high or average risk of breast cancer. Our discovery of epigenetically regulated genes associated with breast cancer risk provides an opportunity to mechanistically dissect breast cancer susceptibility and risk-associated molecular alterations. Unlike the current focus of identifying germline mutations or single nucleotide polymorphisms responsible for higher risk, our studies reveal an epigenetic mechanism, which is not discernable through simple genomic sequencing.

Quality of decision aids developed for women at average risk of breast cancer eligible for mammographic screening: Systematic review and assessment according to the International Patient Decision Aid Standards instrument.

Mammographic screening contributes to a reduction in specific mortality, but it has disadvantages. Decision aids are tools designed to support people's decisions. Because these aids influence patient choice, their quality is crucial. The objective of the current study was to conduct a systematic review of decision aids developed for women eligible for mammographic screening who have an average breast cancer risk and to assess the quality of these aids. The systematic review included articles published between January 1, 1997, and August 1, 2019, in the PubMed, Embase, Cochrane, and PsycInfo databases. The studies were reviewed independently by 2 reviewers. Any study containing a decision aid for women eligible for mammographic screening with an average breast cancer risk was included. Two double-blind reviewers assessed the quality of the selected decision aids using the International Patient Decision Aid Standards instrument, version 3 (IPDASi). Twenty-three decision aids were extracted. Classification of decision aid quality using the IPDASi demonstrated large variations among the decision aids (maximum IPDASi score, 188; mean±SD score, 132.6±23.8; range, 85-172). Three decision aids had high overall scores. The 3 best-rated dimensions were disclosure (maximum score, 8; mean score, 6.8), focusing on transparency; information (maximum score, 32; mean score, 26.1), focusing on the provision of sufficient details; and probabilities (maximum score, 32; mean score 25), focusing on the presentation of probabilities. The 3 lowest-rated dimensions were decision support technology evaluation (maximum score, 8; mean score, 4.3), focusing on the effectiveness of the decision aid; development (maximum score, 24; mean score, 12.6), evaluating the development process; and plain language (maximum score, 4; mean score, 1.9), assessing appropriateness for patients with low literacy. The results of this review identified 3 high-quality decision aids for breast cancer screening.

Breast cancer risk, worry, and anxiety: Effect on patient perceptions of false-positive screening results

ObjectiveThe impact of mammography screening recall on quality-of-life (QOL) has been studied in women at average risk for breast cancer, but it is unknown whether these effects differ by breast cancer risk level. We used a vignette-based survey to evaluate how women across the spectrum of breast cancer risk perceive the experience of screening recall. MethodsWomen participating in mammography or breast MRI screening were recruited to complete a vignette-based survey. Using a numerical rating scale (0–100), women rated QOL for hypothetical scenarios of screening recall, both before and after benign results were known. Lifetime breast cancer risk was calculated using Gail and BRCAPRO risk models. Risk perception, trait anxiety, and breast cancer worry were assessed using validated instruments. ResultsThe final study cohort included 162 women at low (n = 43, 26%), intermediate (n = 66, 41%), and high-risk (n = 53, 33%). Actual breast cancer risk was not a predictor of QOL for any of the presented scenarios. Across all risk levels, QOL ratings were significantly lower for the period during diagnostic uncertainty compared to after benign results were known (p < 0.05). In multivariable regression analyses, breast cancer worry was a significant predictor of decreased QoL for all screening scenarios while awaiting results, including scenarios with non-invasive imaging alone or with biopsy. High trait anxiety and family history predicted lower QOL scores after receipt of benign test results (p < 0.05). ConclusionsWomen with high trait anxiety and family history may particularly benefit from discussions about the risk of recall when choosing a screening regimen.

Digital breast tomosynthesis for breast cancer detection: a diagnostic test accuracy systematic review and meta-analysis.

No consensus exists on digital breast tomosynthesis (DBT) utilization for breast cancer detection. We performed a diagnostic test accuracy systematic review and meta-analysis comparing DBT, combined DBT and digital mammography (DM), and DM alone for breast cancer detection in average-risk women. MEDLINE and EMBASE were searched until September 2018. Comparative design studies reporting on the diagnostic accuracy of DBT and/or DM for breast cancer detection were included. Demographic, methodologic, and diagnostic accuracy data were extracted. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool. Accuracy metrics were pooled using bivariate random-effects meta-analysis. The impact of multiple covariates was assessed using meta-regression. CRD 42018111287. Thirty-eight studies reporting on 488,099 patients (13,923 with breast cancer) were included. Eleven studies were at low risk of bias. DBT alone, combined DBT and DM, and DM alone demonstrated sensitivities of 88% (95% confidence interval [CI] 83-92), 88% (CI 83-92), and 79% (CI 75-82), as well as specificities of 84% (CI 76-89), 81% (CI 73-88), and 79% (CI 71-85), respectively. The greater sensitivities of DBT alone and combined DBT and DM compared to DM alone were preserved in the combined meta-regression models accounting for other covariates (p = 0.003-0.006). No significant difference in diagnostic accuracy between DBT alone and combined DBT and DM was identified (p = 0.175-0.581). DBT is more sensitive than DM, while the addition of DM to DBT provides no additional diagnostic benefit. Consideration of these findings in breast cancer imaging guidelines is recommended. • Digital breast tomosynthesis with or without additional digital mammography is more sensitive in detecting breast cancer than digital mammography alone in women at average risk for breast cancer. • The addition of digital mammography to digital breast tomosynthesis provides no additional diagnostic benefit in detecting breast cancer compared to digital breast tomosynthesis alone. • The specificity of digital breast tomosynthesis with or without additional digital mammography is no different than digital mammography alone in the detection of breast cancer.

Characteristics Associated with Participation in ENGAGED 2 - A Web-based Breast Cancer Risk Communication and Decision Support Trial.

We evaluated demographic and clinical characteristics associated with participation in a clinical trial testing the efficacy of an online tool to support breast cancer risk communication and decision support for risk mitigation to determine the generalizability of trial results. Eligible women were members of Kaiser Permanente Washington aged 40-69 years with a recent normal screening mammogram, heterogeneously or extremely dense breasts and a calculated risk of > 1.67% based on the Breast Cancer Surveillance Consortium 5-year breast cancer risk model. Trial outcomes were chemoprevention and breast magnetic resonance imaging by 12-months post-baseline. Women were recruited via mail with phone follow-up using plain language materials notifying them of their density status and higher than average breast cancer risk. Multivariable logistic regression calculated independent odds ratios (ORs) for associations between demographic and clinical characteristics with trial participation. Of 2,569 eligible women contacted, 995 (38.7%) participated. Women with some college (OR = 1.99, 95% confidence interval [CI] 1.34-2.96) or college degree (OR = 3.35, 95% CI 2.29-4.90) were more likely to participate than high school-educated women. Race/ethnicity also was associated with participation (African-American OR = 0.50, 95% CI 0.29-0.87; Asian OR = 0.22, 95% CI 0.12-0.41). Multivariate adjusted ORs for family history of breast/ovarian cancer were not associated with trial participation. Use of plain language and potential access to a website providing personal breast cancer risk information and education were insufficient in achieving representative participation in a breast cancer prevention trial. Additional methods of targeting and tailoring, potentially facilitated by clinical and community outreach, are needed to facilitate equitable engagement for all women.

Coming changes to mammography standards: With its proposed amendments to update mammography rules, the US Food and Drug Administration hopes to empower patients and health care providers.

Coming changes to mammography standards: With its proposed amendments to update mammography rules, the US Food and Drug Administration hopes to empower patients and health care providers.

Measuring the frequency and variation of unnecessary care across Canada

BackgroundThrough the Choosing Wisely Canada (CWC) campaign, national medical specialty societies have released hundreds of recommendations against health care services that are unnecessary, i.e. present little to no benefit or cause avoidable harm. Despite growing interest in unnecessary care both within Canada and internationally, prior research has typically avoided taking a national or even multi-jurisdictional approach in measuring the extent of the issue. This study estimates use of three unnecessary services identified by CWC recommendations across multiple Canadian jurisdictions.MethodsTwo retrospective cohort studies were conducted using administrative health care data collected between fiscal years 2011/12 and 2012/13 to respectively quantify use of 1) diagnostic imaging (spinal X-ray, CT or MRI) among Albertan patients following a visit for lower back pain and 2) cardiac tests (electrocardiogram, chest X-ray, stress test, or transthoracic echocardiogram) prior to low-risk surgical procedures in Alberta, Saskatchewan, and Ontario. A cross-sectional study of the 2012 Canadian Community Health Survey was also conducted to estimate 3) the proportion of females aged 40–49 that reported having a routine mammogram in the past two years.ResultsUse of unnecessary care was relatively frequent across all three services and jurisdiction measured: 30.7% of Albertan patients had diagnostic imaging within six months of their initial visit for lower back pain; a cardiac test preceded 17.9 to 35.5% of low-risk surgical procedures across Alberta, Saskatchewan, and Ontario; and 22.2% of Canadian women aged 40–49 at average-risk for breast cancer reported having a routine screening mammogram in the past two years.ConclusionsThe use of potentially unnecessary care appears to be common in Canada. This investigation provides methodology to facilitate future measurement efforts that may incorporate additional jurisdictions and/or unnecessary services.

Screening Modalities for Women at Intermediate and High Risk for Breast Cancer

Breast cancer screening is critically important to detect malignancy at an early stage. Annual mammography remains the gold standard as the imaging modality for patients with an average breast cancer risk. However, women with increased breast cancer risk benefit from supplemental screening using additional imaging modalities. This review summarizes the current recommendations within this patient population. Analysis from ACRIN 6666 demonstrated that the cancer detection rate of ultrasound is comparable to mammography with an increased amount of invasive and node-negative cancers detected. Supplemental ultrasound increased the sensitivity and cancer detection rate in the J-START randomized controlled trial. Abbreviated breast MRI and ultrafast breast MRI have demonstrated effective cancer detection performance in the high-risk population. Women with increased breast cancer risk benefit from supplemental screening using digital breast tomosynthesis, ultrasound, and breast MRI. Molecular breast imaging may be considered in some patients.

Is Background Parenchymal Enhancement an Important Risk Factor for Breast Cancer Development in Women with Increased Risk?

Is Background Parenchymal Enhancement an Important Risk Factor for Breast Cancer Development in Women with Increased Risk?

Annals for Educators - 16 April 2019.

Annals for Educators - 16 April 2019.

Screening for Breast Cancer in Average-Risk Women: A Guidance Statement From the American College of Physicians.

The purpose of this guidance statement is to provide advice to clinicians on breast cancer screening in average-risk women based on a review of existing guidelines and the evidence they include. This guidance statement is derived from an appraisal of selected guidelines from around the world that address breast cancer screening, as well as their included evidence. All national guidelines published in English between 1 January 2013 and 15 November 2017 in the National Guideline Clearinghouse or Guidelines International Network library were included. In addition, the authors selected other guidelines commonly used in clinical practice. Web sites associated with all selected guidelines were checked for updates on 10 December 2018. The AGREE II (Appraisal of Guidelines for Research and Evaluation II) instrument was used to evaluate the quality of guidelines. The target audience is all clinicians, and the target patient population is all asymptomatic women with average risk for breast cancer. In average-risk women aged 40 to 49 years, clinicians should discuss whether to screen for breast cancer with mammography before age 50 years. Discussion should include the potential benefits and harms and a woman's preferences. The potential harms outweigh the benefits in most women aged 40 to 49 years. In average-risk women aged 50 to 74 years, clinicians should offer screening for breast cancer with biennial mammography. In average-risk women aged 75 years or older or in women with a life expectancy of 10 years or less, clinicians should discontinue screening for breast cancer. In average-risk women of all ages, clinicians should not use clinical breast examination to screen for breast cancer.

Frequency of Breast Cancer Thoughts and Lifetime Risk Estimates: A Multi-Institutional Survey of Women Undergoing Screening Mammography

PurposeThe aim of this study was to quantify women’s personal estimates of breast cancer risk and frequency of breast cancer thoughts. MethodsWomen from five medical centers were surveyed before their screening mammographic examinations. Participants were queried on their baseline anxiety and demographics, then asked how many times in the past month they had thought about developing breast cancer. Participants were then notified of the 12% lifetime average breast cancer risk and asked to estimate their personal risk both subjectively and objectively. Comparisons were made between responses and the demographic variables. ResultsThere were 2,747 completed surveys for analysis. Women reported 2.5 ± 6.6 thoughts of cancer on average in the prior month. More frequent thoughts were associated with personal or family history of breast cancer, greater anxiety, and genetic testing (P < .001 for all). Among women without cancer risk factors (n = 1,412), there were 1.4 cancer thoughts per month, which was associated with baseline anxiety (P < .001). The median lifetime breast cancer risk was 12% among all women, with 37.4% high risk (>20%) estimates. Demographic variables associated with increased risk estimates were previous cancer diagnosis, higher education, genetic testing, white race, increased age, and greater anxiety (P < .01 for all). Among women with no risk factors, the median estimated risk was 10%, with 16.7% providing estimates greater than 20%, associated with baseline anxiety and white race (P < .001 for both). ConclusionsIncreased breast cancer thoughts and personal cancer estimates are associated with specific patient demographics. Improved understanding of patient perspectives could improve shared decision-making discussions and thus patient care.

Performance of Screening Breast MRI After Negative Full-Field Digital Mammography Versus After Negative Digital Breast Tomosynthesis in Women at Higher Than Average Risk for Breast Cancer

The objective of our study was to compare the supplemental cancer yield and performance of breast MRI in women at higher-than-average risk for breast cancer after negative 2D full-field digital mammography (FFDM) or negative digital breast tomosynthesis (DBT). Retrospective review identified 4418 screening breast MRI examinations: 2291 were performed from January 2010 through January 2012 of patients with a negative FFDM examination in the 12 months before MRI (FFDM group), and 2127 were performed from January 2013 through January 2015 of patients with a negative DBT examination in the 12 months before MRI (DBT group). Screening indications included genetic predisposition, personal history of breast cancer or high-risk lesion, prior chest irradiation, family history, or other risk factors conferring a lifetime risk of greater than 20%. Supplemental cancer detection rate (CDR), abnormal interpretation rate (AIR), and positive predictive values (PPVs) were estimated with 95% exact CIs. Logistic regression analysis, adjusting for differences in patient demographics, was used to compare metrics. There was no significant difference in the CDR of MRI in the FFDM group versus the DBT group (11 vs 16 cancers per 1000 examinations, respectively; odds ratio, 1.4; 95% CI, 0.4-1.2; p = 0.23). The AIR, PPV1, PPV2, and PPV3 were 7.4%, 15%, 23%, and 28% for the FFDM group and 7.3%, 22%, 33%, and 35% for the DBT group, with no statistical differences. Of the cancers detected in both groups, the majority were invasive, less than 1 cm, and node-negative. In women at higher-than-average risk of breast cancer screened with DBT, the supplemental CDR of MRI is similar to that of MRI after FFDM screening, with most cancers being invasive, subcentimeter, and node-negative.

Density and tailored breast cancer screening: practice and prediction - an overview.

Mammography, as the primary screening modality, has facilitated a substantial decrease in breast cancer-related mortality in the general population. However, the sensitivity of mammography for breast cancer detection is decreased in women with higher breast densities, which is an independent risk factor for breast cancer. With increasing public awareness of the implications of a high breast density, there is an increasing demand for supplemental screening in these patients. Yet, improvements in breast cancer detection with supplemental screening methods come at the expense of increased false-positives, recall rates, patient anxiety, and costs. Therefore, breast cancer screening practice must change from a general one-size-fits-all approach to a more personalized, risk-based one that is tailored to the individual woman’s risk, personal beliefs, and preferences, while accounting for cost, potential harm, and benefits.This overview will provide an overview of the available breast density assessment modalities, the current breast density screening recommendations for women at average risk of breast cancer, and supplemental methods for breast cancer screening. In addition, we will provide a look at the possibilities for a risk-adapted breast cancer screening.

Role of magnetic resonance imaging in breast cancer management.

Magnetic resonance imaging (MRI) of the breast is primarily used as a supplemental tool to breast screening with mammography or ultrasound. A breast MRI is mainly used for women who have been diagnosed with breast cancer, to help measure the size of the cancer, look for other tumors in the breast, and to check for tumors in the opposite breast. For certain women at high risk for breast cancer, a screening MRI is recommended along with a yearly mammogram. MRI is known to give some false positive results which mean more test and/or biopsies for the patient. Thus, although breast MRI is useful for women at high risk, it is rarely recommended as a screening test for women at average risk of breast cancer. Also, breast MRI does not show calcium deposits, known as micro-calcifications which can be a sign of breast cancer.

Screening mammography for average-risk women.

This Practice Pearl describes an approach to screening mammography for average-risk women that encourages the use of shared decision-making that addresses benefits (early diagnosis and decreased mortality) and potential harms (false positives and overdiagnosis/overtreatment) in determining screening mammography initiation, frequency, and duration for women at average risk of breast cancer.

Not all false positive diagnoses are equal: On the prognostic implications of false-positive diagnoses made in breast MRI versus in mammography / digital tomosynthesis screening

BackgroundBreast magnetic resonance imaging (MRI) has been reported to frequently result in false-positive diagnoses, limiting its positive predictive value (PPV). However, for PPV calculation, all nonmalignant tissue changes are equally considered false-positive, although the respective prognostic importance, and thus patient management implications, of different pathologies may well differ. We investigated the pathology of false-positive diagnoses made by MRI compared with radiographic (digital mammography/tomosynthesis [DM/DBT]) screening.MethodsWe conducted an institutional review board-approved prospective analysis of 710 consecutive asymptomatic women at average risk for breast cancer who underwent vacuum biopsy with or without surgical biopsy for screen-detected DM/DBT (n = 344) or MRI (n = 366) findings. We compared the frequency of false-positive biopsies (given by PPV3), as well as the types of nonmalignant tissue changes that caused the respective false-positive biopsies. In an order of increasing relative risk of subsequent breast cancer, pathologies of false-positive biopsies were categorized as nonproliferative, simple proliferative, complex proliferative, or atypical proliferative (including lobular carcinoma in situ/lobular intraepithelial neoplasia). The Mann-Whitney U test was used to compare distributions.ResultsHistology yielded nonmalignant tissue in 202 of 366 biopsies done for positive MRI studies and 195 of 344 biopsies for positive DM/DBT studies, respectively, yielding a similar PPV3 percentages of 44.8% (164 of 202) and 43.3% (149 of 202) for both methods. However, the distribution of tissue types that caused false-positive diagnoses differed significantly (p < 0.0001). On the basis of MRI, high-risk atypical proliferative changes (40.1%; 81 of 202) were most common, followed by complex proliferative changes (23.8%; 48 of 202). In DM/DBT, low-risk, nonproliferative changes were the dominant reason for false-positive diagnoses (49.7%; 97 of 195), followed by simple proliferative changes (25.2%; 51 of 195). Low-risk nonproliferative changes resulted in false-positive diagnoses based on MRI as infrequently as did high-risk atypical proliferative changes based on DM/DBT (18.8% [38 of 202] vs. 18.0% [35 of 195]). The likelihood of a false-positive diagnosis including atypias was twice as high in women undergoing biopsy for MRI findings (81 of 202; 40%) as for those with DM/DBT findings (35 of 195; 18%).ConclusionsThe prognostic importance, and thus the clinical implications, of false-positive diagnoses made on the basis of breast MRI vs. radiographic screening differed significantly, with a reversed prevalence of high- and low-risk lesions. This should be taken into account when discussing the rate of false-positive diagnoses (i.e., PPV levels of MRI vs. radiographic screening). Current benchmarks that rate the utility of breast cancer screening programs (i.e., cancer detection rates and PPVs) do not reflect these substantial biological differences and the different prognostic implications.