Prevalent vs Incident Screen: Why Does It Matter?

There are important differences in the performance and outcomes of breast cancer screening in the prevalent compared to the incident screening rounds. The prevalent screen is the first screening examination using a particular imaging technique and identifies pre-existing, undiagnosed cancers in the population. The incident screen is any subsequent screening examination using that technique. It is expected to identify fewer cancers than the prevalent screen because it captures only those cancers that have become detectable since the prior screening examination. The higher cancer detection rate at prevalent relative to incident screening should be taken into account when analyzing the medical audit and effectiveness of new screening technologies.

Performance of screening MRI in high risk patients at initial versus subsequent screen.

PURPOSE: To compare the characteristics, outcomes, and performance metrics in women undergoing initial breast MRI screening versus subsequent screening. METHODS: A retrospective database search identified screening MRIs performed at an academic practice from 2013 to 2015. MRIs were divided into two groups: (1) initial screens and (2) subsequent screens (interpreted with at least one prior MRI for comparison). Benignity was confirmed with pathology or >1-year follow-up. Malignancy was confirmed by pathology. Performance metrics were calculated. Comparisons were made using Binomial and Fisher's exact tests. RESULTS: We observed a higher rate of abnormal interpretations (52% vs. 19%; p < 0.001) and rate of biopsy (49% vs. 15%; p < 0.001) in the initial versus subsequent screen group. The positive predictive value of biopsy was slightly lower at initial versus subsequent screen (17% vs. 19%, p = 0.99). However, the cancer detection rate was higher at initial than at subsequent screen (85 vs. 29/1000, p = 0.08). Sensitivity was higher at initial (100%) versus subsequent (88%) screen. However, the specificity at initial screen was low (55%) compared to subsequent screen (83%). CONCLUSIONS: The higher rate of abnormal interpretations in the initial versus subsequent screen group in part reflects a prevalence screening. Although we observed more abnormal interpretations in the initial screen, this was likely justified by the significantly higher cancer detection. This evidence may be used to counsel patients and referring providers on the expected higher likelihood of recall from an initial screening MRI balanced with higher detection of malignancies. Findings also highlight the importance of having comparison MRIs to decrease false positives.

Cancer Yield and Patterns of Follow-up for BI-RADS Category 3 after Screening Mammography Recall in the National Mammography Database.

Background The literature supports the use of short-interval follow-up as an alternative to biopsy for lesions assessed as probably benign, Breast Imaging Reporting and Data System (BI-RADS) category 3, with an expected malignancy rate of less than 2%. Purpose To assess outcomes from 6-, 12-, and 24-month follow-up of probably benign findings first identified at recall from screening mammography in the National Mammography Database (NMD). Materials and Methods This retrospective study included women recalled from screening mammography with BI-RADS category 3 assessment at additional evaluation from January 2009 through March 2018 from 471 NMD facilities. Only the first BI-RADS category 3 occurrence for women aged 25 years or older with no personal history of breast cancer was analyzed, with biopsy or 2-year imaging follow-up. Cancer yield and positive predictive value of biopsies performed (PPV3) were determined at each follow-up. Results Among 45 202 women (median age, 55 years; range, 25-90 years) with a BI-RADS category 3 lesion, 1574 (3.5%) underwent biopsy at the time of lesion detection, yielding 72 cancers (cancer yield, 4.6%; 72 of 1574 women). For the remaining 43 628 women who accepted surveillance, 922 were seen within 90 days (with 78 lesions biopsied and 12 [15%] classified as malignant). The women still in surveillance (31 465 of 43 381 women [72.5%]) underwent follow-up mammography at 6 months. Of 3001 (9.5%) lesions biopsied, 456 (15.2%) were malignant (cancer yield, 1.5%; 456 of 31 465 women; 95% confidence interval [CI]: 1.3%, 1.6%). Among 18 748 of 25 997 women (72.1%) in surveillance who underwent follow-up at 12 months, 1219 (6.5%) underwent biopsy with 230 (18.9%) malignant lesions found (cancer yield, 1.2%; 230 of 18 748 women; 95% CI: 1.1%, 1.4%). Through 2-year follow-up, the biopsy rate was 11.2% (4894 of 43 628 women) with a cancer yield of 1.86% (810 malignancies found among 43 628 women; 95% CI: 1.73%, 1.98%) and a PPV3 of 16.6% (810 malignancies found among 4894 women). Conclusion In the National Mammography Database, Breast Imaging Reporting and Data System (BI-RADS) category 3 use is appropriate, with 1.86% cumulative cancer yield through 2-year follow-up. Of 810 malignancies, 468 (57.8%) were diagnosed at or before 6 months, validating necessity of short-interval follow-up of mammographic BI-RADS category 3 findings. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Moy in this issue.

Risk-Based Screening Mammography for Women Aged <40: Outcomes From the National Mammography Database.

OBJECTIVE: There is insufficient large-scale evidence for screening mammography in women <40 years at elevated risk. This study compares risk-based screening of women aged 30 to 39 with risk factors versus women aged 40 to 49 without risk factors in the National Mammography Database (NMD). METHODS: This retrospective, HIPAA-compliant, institutional review board-exempt study analyzed data from 150 NMD mammography facilities in 31 states. Patients were stratified by 5-year age intervals, availability of prior mammograms, and specific risk factors for breast cancer: family history of breast cancer, personal history of breast cancer, and dense breasts. Four screening performance metrics were calculated for each age and risk group: recall rate (RR), cancer detection rate (CDR), and positive predictive values for biopsy recommended (PPV2) and biopsy performed (PPV3). RESULTS: Data from 5,986,131 screening mammograms performed between January 2008 and December 2015 in 2,647,315 women were evaluated. Overall, mean CDR was 3.69 of 1,000 (95% confidence interval: 3.64-3.74), RR was 9.89% (9.87%-9.92%), PPV2 was 20.1% (19.9%-20.4%), and PPV3 was 28.2% (27.0%-28.5%). Women aged 30 to 34 and 35 to 39 had similar CDR, RR, and PPVs, with the presence of the three evaluated risk factors associated with significantly higher CDR. Moreover, compared with a population currently recommended for screening mammography in the United States (aged 40-49 at average risk), incidence screening (at least one prior screening examination) of women aged 30 to 39 with the three evaluated risk factors has similar cancer detection rates and recall rates. DISCUSSION: Women with one or more of these three specific risk factors likely benefit from screening commencing at age 30 instead of age 40.

Linkage of the ACR National Mammography Database to the Network of State Cancer Registries: Proof of Concept Evaluation by the ACR National Mammography Database Committee.

PURPOSE: The National Mammography Database (NMD) contains nearly 20 million examinations from 693 facilities; it is the largest information source for use and effectiveness of breast imaging in the United States. NMD collects demographic, imaging, interpretation, biopsy, and basic pathology results, enabling facility and physician comparison for quality improvement. However, NMD lacks treatment and clinical outcomes data. The network of state cancer registries (CRs) contains detailed pathologic, treatment, and clinical outcomes data. This pilot study assessed electronic linkage of NMD and CR data at a multicenter institution as proof of concept. MATERIALS AND METHODS: We obtained Quality Oversight Committee approval for this retrospective study. Data of patients diagnosed with breast cancer in 2014 and 2015 were retrieved from our NMD-approved radiology information system (RIS) and matched with reportable patients in our CR using social security number (SSN), first name (fname), last name (lname), and date of birth (DOB). Matching was repeated without SSN. Percentage and reasons for mismatch were evaluated. RESULTS: The RIS query identified 1,316 patients. CR linkage was 99.2% successful (n = 1,305 of 1,316) using SSN, fname, lname, and DOB. Eleven mismatches included four CR case-finding failures, one NMD fname error, five nonreportable in the CR, and one with correct identifiers in both databases. Without SSN, linkage was 97.3% successful (n = 1,281 of 1,316); name errors accounted for 19 and DOB accounted for 5 additional mismatches. CONCLUSION: Using common data elements, linkage between the NMD and state CRs may be feasible and could provide critical outcomes information to advance accurate assessment of breast imaging in the United States.

BI-RADS Category 5 Assessments at Diagnostic Breast Imaging:Outcomes Analysis Based on Lesion Descriptors.

RATIONALE AND OBJECTIVES: The Breast Imaging-Reporting and Data System (BI-RADS) atlas defines category 5 assessments as appropriate only for lesions that are almost certainly cancer, with a positive predictive value (PPV) of ≥95%. This study aims to demonstrate the feasibility of classifying lesions at diagnostic breast imaging with sufficiently high PPV to merit category 5 assessments, and to identify those lesion descriptors that yield such a high PPV. MATERIALS AND METHODS: For this Health Insurance Portability and Accountability Act compliant and IRB exempt study, we reviewed diagnostic breast imaging examinations (mammography and/or ultrasound) assessed as highly suggestive of malignancy (BI-RADS category 5). Pathology diagnosis was considered the gold standard. PPV3 (biopsy performed) was calculated, and the BI-RADS descriptors for each lesion were analyzed. RESULTS: Among 22,564 consecutive diagnostic breast imaging examinations between January 2010 and September 2015, we identified 239 exams (1.1%) assessed as BI-RADS category 5 (mean age 62.5 years). Malignancy (invasive breast carcinoma and/or ductal carcinoma in situ) was diagnosed in 233 examinations (PPV3 97.5% and 95% confidence interval: 96.2%-98.8%). The most common lesion types were mass (170) and calcifications (116). Of the 220 examinations involving both mammography and ultrasound, no category 5 lesions had <3 suspicious BI-RADS descriptors, only three lesions had three suspicious descriptors, but the remaining 217 lesions (98.6%) had ≥4 suspicious descriptors. CONCLUSION: In clinical practice, it is feasible to make BI-RADS category 5 assessments with the intended ≥95% PPV. To justify a category 5 assessment, at least four suspicious BI-RADS descriptors should be identified at the combination of diagnostic mammography and ultrasound examinations.

Risk Stratification for Screening Mammography: Benefits and Harms.

OBJECTIVE: The purpose of this article is to compare commonly used breast cancer risk assessment models, describe the machine learning approach and big data in risk prediction, and summarize the potential benefits and harms of restrictive risk-based screening. CONCLUSION: The commonly used risk assessment models for breast cancer can be complex and cumbersome to use. Each model incorporates different sets of risk factors, which are weighted differently and can produce different results for the same patient. No model is appropriate for all subgroups of the general population and only one model incorporates mammographic breast density. Future development of risk prediction tools that are generalizable and simpler to use are needed in guiding clinical decisions.

Breast Cancer Screening in Women at Higher-Than-Average Risk: Recommendations From the ACR.

Early detection decreases breast cancer mortality. The ACR recommends annual mammographic screening beginning at age 40 for women of average risk. Higher-risk women should start mammographic screening earlier and may benefit from supplemental screening modalities. For women with genetics-based increased risk (and their untested first-degree relatives), with a calculated lifetime risk of 20% or more or a history of chest or mantle radiation therapy at a young age, supplemental screening with contrast-enhanced breast MRI is recommended. Breast MRI is also recommended for women with personal histories of breast cancer and dense tissue, or those diagnosed by age 50. Others with histories of breast cancer and those with atypia at biopsy should consider additional surveillance with MRI, especially if other risk factors are present. Ultrasound can be considered for those who qualify for but cannot undergo MRI. All women, especially black women and those of Ashkenazi Jewish descent, should be evaluated for breast cancer risk no later than age 30, so that those at higher risk can be identified and can benefit from supplemental screening.

Use of the probably benign (BI-RADS category 3) assessment for masses on breast MRI: Is it transferable to general clinical practice?

The purpose of this study was to identify potential BI-RADS 3 mass descriptors on breast magnetic resonance imaging by systematically defining positive predictive values (PPV). In a blinded retrospective review of BI-RADS 4 masses, reader 1 identified 132 masses and reader 2 identified 76 masses. PPV for mass descriptors and for descriptor combinations was determined. No mass descriptor resulted in a PPV ≤2% (BI-RADS 3 threshold). Descriptors with the lowest PPVs were circumscribed margin (8%), rim internal enhancement and persistent kinetics (13% each), and oval shape (15%). The results demonstrate the difficulty in transferring the theoretical concept of lesion surveillance to systematic clinical use.

Screening for Breast Cancer in Women Age 75 Years and Older.

OBJECTIVE: Older women undergoing regular mammography experience significant reductions in breast cancer mortality, except in women with severe comorbidities or limited life expectancy. Optimizing screening strategies requires informed discussions of benefits and risks given each woman's health status. CONCLUSION: This article will review the benefits and risks of screening mammography in women older than 75 years within the context of life expectancy and comorbidities and summarize the current recommendations from professional organizations for screening mammography in older women.

Screening Mammography in Women 40-49 Years Old: Current Evidence.

OBJECTIVE: Breast cancer is an important health problem for women 40-49 years old, yet screening mammography for this age group remains controversial. This article reviews recent guidelines and supporting evidence on screening mammography in women of this age group. CONCLUSION: Evidence supports the benefit of annual screening mammography in women 40-49 years old. Models of different breast cancer screening strategies consistently show the greatest breast cancer mortality reduction and life-years gained with annual screening starting when women reach 40 years old.

Harmonizing Breast Cancer Screening Recommendations: Metrics and Accountability.

OBJECTIVE: The purposes of this article are to summarize breast cancer screening recommendations and discuss their differences and similarities and to explain the differences between two national databases to aid in interpretation of their benchmarks. CONCLUSION: The American College of Radiology, American Cancer Society, and U.S. Preventive Services Task Force all agree that annual mammography beginning at age 40 saves the most lives, and all acknowledge a woman's right to choose when to begin and stop screening. The National Mammography Database (NMD) differs from the Breast Cancer Surveillance Consortium database in that it acquires data using the same approach used by almost all mammography facilities in the United States. Therefore, NMD benchmarks, which include standard metrics, provide more meaningful comparisons to help mammography facilities and radiologists improve performance.

Comparison of recommendations for screening mammography using CISNET models.

BACKGROUND: Currently, there are several different recommendations for screening mammography from major national health care organizations, including: 1) annual screening at ages 40 to 84 years; 2) screening annually at ages 45 to 54 years, then biennially at ages 55 to 79 years; and 3) biennial screening at ages 50 to 74 years. METHODS: Mean values of six Cancer Intervention and Surveillance Modeling Network (CISNET) models were used to compare these three screening mammography recommendations in terms of benefits and risks. RESULTS: Mean mortality reduction was greatest with the recommendation of annual screening at ages 40 to 84 years (39.6%), compared with the hybrid recommendation of screening annually at ages 45 to 54 years, then biennially at ages 55 to 79 years (30.8%), and the recommendation of biennial screening at ages 50 to 74 years (23.2%). For a single-year cohort of US women aged 40 years, assuming 100% compliance, more breast cancers deaths would be averted over their lifetime with annual screening starting at age 40 (29,369) than with the hybrid recommendation (22,829) or biennial screening ages 50-74 (17,153 based on 2009 CISNET estimates, 15,599 based on 2016 CISNET estimates). To achieve the greatest mortality benefit, this single-year cohort of women would have the greatest total number of screening mammograms, benign recalls, and benign biopsies performed over the course of screening by following annual screening starting at age 40 years (90.2 million, 6.8 million, and 481,269, respectively) than by following the hybrid recommendation (49.0 million, 4.1 million, and 286,288, respectively) or biennial screening at ages 50 to 74 years (27.3 million, 2.3 million, and 162,885, respectively). CONCLUSION: CISNET models demonstrate that the greatest mortality reduction is achieved with annual screening of women starting at age 40 years. Cancer 2017;123:3673-3680. © 2017 American Cancer Society.

Breast Cancer Screening for Average-Risk Women: Recommendations From the ACR Commission on Breast Imaging.

Breast cancer is the most common non-skin cancer and the second leading cause of cancer death for women in the United States. Before the introduction of widespread mammographic screening in the mid-1980s, the death rate from breast cancer in the US had remained unchanged for more than 4 decades. Since 1990, the death rate has declined by at least 38%. Much of this change is attributed to early detection with mammography. ACR breast cancer screening experts have reviewed data from RCTs, observational studies, US screening data, and other peer-reviewed literature to update our recommendations. Mammography screening has consistently been shown to significantly reduce breast cancer mortality over a variety of study designs. The ACR recommends annual mammography screening starting at age 40 for women of average risk of developing breast cancer. Our recommendation is based on maximizing proven benefits, which include a substantial reduction in breast cancer mortality afforded by regular screening and improved treatment options for those diagnosed with breast cancer. The risks associated with mammography screening are also considered to assist women in making an informed choice.

Persistent Untreated Screening-Detected Breast Cancer: An Argument Against Delaying Screening or Increasing the Interval Between Screenings.

PURPOSE: The aim of this study was to investigate the natural history of untreated screen-detected breast cancer. METHODS: A prospective cohort survey of Society of Breast Imaging fellows concerning the appearance on subsequent mammography of untreated breast cancer detected on screening mammography was conducted. RESULTS: A representative sample of the 108 actively practicing Society of Breast Imaging fellows (n = 42 [39%]) participated, each reporting outcomes data from his or her entire screening mammography practice. Among all practices, 25,281 screen-detected invasive breast cancers and 9,360 cases of screen-detected ductal carcinoma in situ were reported over the past 10 years. Among these cancers, there were 240 cases of untreated invasive breast cancer and 239 cases of untreated ductal carcinoma in situ, among which zero were reported to have spontaneously disappeared or regressed at next mammography. CONCLUSIONS: Among 479 untreated breast cancers detected on screening mammography, none spontaneously disappeared or regressed. An unknown percentage of these cancers represent overdiagnosis, but because all untreated screen-detected cancers were visible and suspicious for malignancy at next mammographic examination, delaying the onset of screening or increasing the interval between screenings should not reduce the frequency of overdiagnosis.