Benefits and Harms of Mammography Screening in 75 + Women to Inform Shared Decision-making: a Simulation Modeling Study.

BACKGROUND: Guidelines recommend shared decision-making (SDM) around mammography screening for women ≥ 75 years old. OBJECTIVE: To use microsimulation modeling to estimate the lifetime benefits and harms of screening women aged 75, 80, and 85 years based on their individual risk factors (family history, breast density, prior biopsy) and comorbidity level to support SDM in clinical practice. DESIGN, SETTING, AND PARTICIPANTS: We adapted two established Cancer Intervention and Surveillance Modeling Network (CISNET) models to evaluate the remaining lifetime benefits and harms of screening U.S. women born in 1940, at decision ages 75, 80, and 85 years considering their individual risk factors and comorbidity levels. Results were summarized for average- and higher-risk women (defined as having breast cancer family history, heterogeneously dense breasts, and no prior biopsy, 5% of the population). MAIN OUTCOMES AND MEASURES: Remaining lifetime breast cancers detected, deaths (breast cancer/other causes), false positives, and overdiagnoses for average- and higher-risk women by age and comorbidity level for screening (one or five screens) vs. no screening per 1000 women. RESULTS: Compared to stopping, one additional screen at 75 years old resulted in six and eight more breast cancers detected (10% overdiagnoses), one and two fewer breast cancer deaths, and 52 and 59 false positives per 1000 average- and higher-risk women without comorbidities, respectively. Five additional screens over 10 years led to 23 and 31 additional breast cancer cases (29-31% overdiagnoses), four and 15 breast cancer deaths avoided, and 238 and 268 false positives per 1000 average- and higher-risk screened women without comorbidities, respectively. Screening women at older ages (80 and 85 years old) and high comorbidity levels led to fewer breast cancer deaths and a higher percentage of overdiagnoses. CONCLUSIONS: Simulation models show that continuing screening in women ≥ 75 years old results in fewer breast cancer deaths but more false positive tests and overdiagnoses. Together, clinicians and 75 + women may use model output to weigh the benefits and harms of continued screening.

Collaborative Modeling to Compare Different Breast Cancer Screening Strategies: A Decision Analysis for the US Preventive Services Task Force.

Importance: The effects of breast cancer incidence changes and advances in screening and treatment on outcomes of different screening strategies are not well known. Objective: To estimate outcomes of various mammography screening strategies. Design, Setting, and Population: Comparison of outcomes using 6 Cancer Intervention and Surveillance Modeling Network (CISNET) models and national data on breast cancer incidence, mammography performance, treatment effects, and other-cause mortality in US women without previous cancer diagnoses. Exposures: Thirty-six screening strategies with varying start ages (40, 45, 50 years) and stop ages (74, 79 years) with digital mammography or digital breast tomosynthesis (DBT) annually, biennially, or a combination of intervals. Strategies were evaluated for all women and for Black women, assuming 100% screening adherence and "real-world" treatment. Main Outcomes and Measures: Estimated lifetime benefits (breast cancer deaths averted, percent reduction in breast cancer mortality, life-years gained), harms (false-positive recalls, benign biopsies, overdiagnosis), and number of mammograms per 1000 women. Results: Biennial screening with DBT starting at age 40, 45, or 50 years until age 74 years averted a median of 8.2, 7.5, or 6.7 breast cancer deaths per 1000 women screened, respectively, vs no screening. Biennial DBT screening at age 40 to 74 years (vs no screening) was associated with a 30.0% breast cancer mortality reduction, 1376 false-positive recalls, and 14 overdiagnosed cases per 1000 women screened. Digital mammography screening benefits were similar to those for DBT but had more false-positive recalls. Annual screening increased benefits but resulted in more false-positive recalls and overdiagnosed cases. Benefit-to-harm ratios of continuing screening until age 79 years were similar or superior to stopping at age 74. In all strategies, women with higher-than-average breast cancer risk, higher breast density, and lower comorbidity level experienced greater screening benefits than other groups. Annual screening of Black women from age 40 to 49 years with biennial screening thereafter reduced breast cancer mortality disparities while maintaining similar benefit-to-harm trade-offs as for all women. Conclusions: This modeling analysis suggests that biennial mammography screening starting at age 40 years reduces breast cancer mortality and increases life-years gained per mammogram. More intensive screening for women with greater risk of breast cancer diagnosis or death can maintain similar benefit-to-harm trade-offs and reduce mortality disparities.

Breast cancer risk characteristics of women undergoing whole-breast ultrasound screening versus mammography alone.

BACKGROUND: There are no consensus guidelines for supplemental breast cancer screening with whole-breast ultrasound. However, criteria for women at high risk of mammography screening failures (interval invasive cancer or advanced cancer) have been identified. Mammography screening failure risk was evaluated among women undergoing supplemental ultrasound screening in clinical practice compared with women undergoing mammography alone. METHODS: A total of 38,166 screening ultrasounds and 825,360 screening mammograms without supplemental screening were identified during 2014-2020 within three Breast Cancer Surveillance Consortium (BCSC) registries. Risk of interval invasive cancer and advanced cancer were determined using BCSC prediction models. High interval invasive breast cancer risk was defined as heterogeneously dense breasts and BCSC 5-year breast cancer risk ≥2.5% or extremely dense breasts and BCSC 5-year breast cancer risk ≥1.67%. Intermediate/high advanced cancer risk was defined as BCSC 6-year advanced breast cancer risk ≥0.38%. RESULTS: A total of 95.3% of 38,166 ultrasounds were among women with heterogeneously or extremely dense breasts, compared with 41.8% of 825,360 screening mammograms without supplemental screening (p < .0001). Among women with dense breasts, high interval invasive breast cancer risk was prevalent in 23.7% of screening ultrasounds compared with 18.5% of screening mammograms without supplemental imaging (adjusted odds ratio, 1.35; 95% CI, 1.30-1.39); intermediate/high advanced cancer risk was prevalent in 32.0% of screening ultrasounds versus 30.5% of screening mammograms without supplemental screening (adjusted odds ratio, 0.91; 95% CI, 0.89-0.94). CONCLUSIONS: Ultrasound screening was highly targeted to women with dense breasts, but only a modest proportion were at high mammography screening failure risk. A clinically significant proportion of women undergoing mammography screening alone were at high mammography screening failure risk.

Estimation of Breast Cancer Overdiagnosis in a U.S. Breast Screening Cohort.

BACKGROUND: Mammography screening can lead to overdiagnosis-that is, screen-detected breast cancer that would not have caused symptoms or signs in the remaining lifetime. There is no consensus about the frequency of breast cancer overdiagnosis. OBJECTIVE: To estimate the rate of breast cancer overdiagnosis in contemporary mammography practice accounting for the detection of nonprogressive cancer. DESIGN: Bayesian inference of the natural history of breast cancer using individual screening and diagnosis records, allowing for nonprogressive preclinical cancer. Combination of fitted natural history model with life-table data to predict the rate of overdiagnosis among screen-detected cancer under biennial screening. SETTING: Breast Cancer Surveillance Consortium (BCSC) facilities. PARTICIPANTS: Women aged 50 to 74 years at first mammography screen between 2000 and 2018. MEASUREMENTS: Screening mammograms and screen-detected or interval breast cancer. RESULTS: The cohort included 35 986 women, 82 677 mammograms, and 718 breast cancer diagnoses. Among all preclinical cancer cases, 4.5% (95% uncertainty interval [UI], 0.1% to 14.8%) were estimated to be nonprogressive. In a program of biennial screening from age 50 to 74 years, 15.4% (UI, 9.4% to 26.5%) of screen-detected cancer cases were estimated to be overdiagnosed, with 6.1% (UI, 0.2% to 20.1%) due to detecting indolent preclinical cancer and 9.3% (UI, 5.5% to 13.5%) due to detecting progressive preclinical cancer in women who would have died of an unrelated cause before clinical diagnosis. LIMITATIONS: Exclusion of women with first mammography screen outside BCSC. CONCLUSION: On the basis of an authoritative U.S. population data set, the analysis projected that among biennially screened women aged 50 to 74 years, about 1 in 7 cases of screen-detected cancer is overdiagnosed. This information clarifies the risk for breast cancer overdiagnosis in contemporary screening practice and should facilitate shared and informed decision making about mammography screening. PRIMARY FUNDING SOURCE: National Cancer Institute.

Cost-Effectiveness of Screening Mammography Beyond Age 75 Years : A Cost-Effectiveness Analysis.

BACKGROUND: The cost-effectiveness of screening mammography beyond age 75 years remains unclear. OBJECTIVE: To estimate benefits, harms, and cost-effectiveness of extending mammography to age 80, 85, or 90 years according to comorbidity burden. DESIGN: Markov microsimulation model. DATA SOURCES: SEER (Surveillance, Epidemiology, and End Results) program and Breast Cancer Surveillance Consortium. TARGET POPULATION: U.S. women aged 65 to 90 years in groups defined by Charlson comorbidity score (CCS). TIME HORIZON: Lifetime. PERSPECTIVE: National health payer. INTERVENTION: Screening mammography to age 75, 80, 85, or 90 years. OUTCOME MEASURES: Breast cancer death, survival, and costs. RESULTS OF BASE-CASE ANALYSIS: Extending biennial mammography from age 75 to 80 years averted 1.7, 1.4, and 1.0 breast cancer deaths and increased days of life gained by 5.8, 4.2, and 2.7 days per 1000 women for comorbidity scores of 0, 1, and 2, respectively. Annual mammography beyond age 75 years was not cost-effective, but extending biennial mammography to age 80 years was ($54 000, $65 000, and $85 000 per quality-adjusted life-year [QALY] gained for women with CCSs of 0, 1, and ≥2, respectively). Overdiagnosis cases were double the number of deaths averted from breast cancer. RESULTS OF SENSITIVITY ANALYSIS: Costs per QALY gained were sensitive to changes in invasive cancer incidence and shift of breast cancer stage with screening mammography. LIMITATION: No randomized controlled trials of screening mammography beyond age 75 years are available to provide model parameter inputs. CONCLUSION: Although annual mammography is not cost-effective, biennial screening mammography to age 80 years is; however, the absolute number of deaths averted is small, especially for women with comorbidities. Women considering screening beyond age 75 years should weigh the potential harms of overdiagnosis versus the potential benefit of averting death from breast cancer. PRIMARY FUNDING SOURCE: National Cancer Institute and National Institutes of Health.

Mammography adherence in relation to function-related indicators in older women.

Prior studies of screening mammography patterns by functional status in older women show inconsistent results. We used Breast Cancer Surveillance Consortium-Medicare linked data (1999-2014) to investigate the association of functional limitations with adherence to screening mammography in 145,478 women aged 66-74 years. Functional limitation was represented by a claims-based function-related indicator (FRI) score which incorporated 16 items reflecting functional status. Baseline adherence was defined as mammography utilization 9-30 months after the index screening mammography. Longitudinal adherence was examined among women adherent at baseline and defined as time from the index mammography to end of the first 30-month gap in mammography. Multivariable logistic regression and Cox proportional hazards models were used to investigate baseline and longitudinal adherence, respectively. Subgroup analyses were conducted by age (66-70 vs. 71-74 years). Overall, 69.6% of participants had no substantial functional limitation (FRI score 0), 23.5% had some substantial limitations (FRI score 1), and 6.8% had serious limitations (FRI score ≥ 2). Mean age at baseline was 68.5 years (SD = 2.6), 85.3% of participants were white, and 77.1% were adherent to screening mammography at baseline. Women with a higher FRI score were more likely to be non-adherent at baseline (FRI ≥ 2 vs. 0: aOR = 1.13, 95% CI = 1.06, 1.20, p-trend < 0.01). Similarly, a higher FRI score was associated with longitudinal non-adherence (FRI ≥ 2 vs. 0: aHR = 1.16, 95% CI = 1.11, 1.22, p-trend < 0.01). Effect measures of FRI did not differ substantially by age categories. Older women with a higher burden of functional limitations are less likely to be adherent to screening mammography recommendations.

Association of Screening With Digital Breast Tomosynthesis vs Digital Mammography With Risk of Interval Invasive and Advanced Breast Cancer.

Importance: Digital breast tomosynthesis (DBT) was developed with the expectation of improving cancer detection in women with dense breasts. Studies are needed to evaluate interval invasive and advanced breast cancer rates, intermediary outcomes related to breast cancer mortality, by breast density and breast cancer risk. Objective: To evaluate whether DBT screening is associated with a lower likelihood of interval invasive cancer and advanced breast cancer compared with digital mammography by extent of breast density and breast cancer risk. Design, Setting, and Participants: Cohort study of 504 427 women aged 40 to 79 years who underwent 1 003 900 screening digital mammography and 375 189 screening DBT examinations from 2011 through 2018 at 44 US Breast Cancer Surveillance Consortium (BCSC) facilities with follow-up for cancer diagnoses through 2019 by linkage to state or regional cancer registries. Exposures: Breast Imaging Reporting and Data System (BI-RADS) breast density; BCSC 5-year breast cancer risk. Main Outcomes and Measures: Rates per 1000 examinations of interval invasive cancer within 12 months of screening mammography and advanced breast cancer (prognostic pathologic stage II or higher) within 12 months of screening mammography, both estimated with inverse probability weighting. Results: Among 504 427 women in the study population, the median age at time of mammography was 58 years (IQR, 50-65 years). Interval invasive cancer rates per 1000 examinations were not significantly different for DBT vs digital mammography (overall, 0.57 vs 0.61, respectively; difference, -0.04; 95% CI, -0.14 to 0.06; P = .43) or among all the 836 250 examinations with BCSC 5-year risk less than 1.67% (low to average-risk) or all the 413 061 examinations with BCSC 5-year risk of 1.67% or higher (high risk) across breast density categories. Advanced cancer rates were not significantly different for DBT vs digital mammography among women at low to average risk or at high risk with almost entirely fatty, scattered fibroglandular densities, or heterogeneously dense breasts. Advanced cancer rates per 1000 examinations were significantly lower for DBT vs digital mammography for the 3.6% of women with extremely dense breasts and at high risk of breast cancer (13 291 examinations in the DBT group and 31 300 in the digital mammography group; 0.27 vs 0.80 per 1000 examinations; difference, -0.53; 95% CI, -0.97 to -0.10) but not for women at low to average risk (10 611 examinations in the DBT group and 37 796 in the digital mammography group; 0.54 vs 0.42 per 1000 examinations; difference, 0.12; 95% CI, -0.09 to 0.32). Conclusions and Relevance: Screening with DBT vs digital mammography was not associated with a significant difference in risk of interval invasive cancer and was associated with a significantly lower risk of advanced breast cancer among the 3.6% of women with extremely dense breasts and at high risk of breast cancer. No significant difference was observed in the 96.4% of women with nondense breasts, heterogeneously dense breasts, or with extremely dense breasts not at high risk.

Prioritizing breast imaging services during the COVID pandemic: A survey of breast imaging facilities within the Breast Cancer Surveillance Consortium.

The COVID-19 pandemic disrupted breast cancer screening and diagnostic imaging in the United States. We sought to evaluate how medical facilities prioritized breast imaging services during periods of reduced capacity or upon re-opening after closures. In fall 2020, we surveyed 77 breast imaging facilities within the Breast Cancer Surveillance Consortium in the United States. The survey ascertained the pandemic's impact on clinical practices during March-September 2020. Nearly all facilities (97%) reported closing or operating at reduced capacity at some point during this period. All facilities were open by August 2020, though 14% were still operating at reduced capacity in September 2020. During periods of re-opening or reduced capacity, 93% of facilities reported prioritizing diagnostic breast imaging over breast cancer screening. For diagnostic imaging, facilities prioritized based on rescheduling canceled appointments (89%), specific indication for diagnostic imaging (89%), patient demand (84%), individual characteristics and risk factors (77%), and time since last imaging examination (72%). For screening mammography, facilities prioritized based on rescheduled cancelations (96%), patient demand (83%), individual characteristics and risk factors (73%), and time since last mammogram (71%). For biopsy services, more than 90% of facilities reported prioritization based on rescheduling of canceled exams, patient demand, patient characteristics and risk factors and level of suspicion on imaging. The observed patterns from this large and geographically diverse sample of facilities in the United States indicate that multiple factors were commonly used to prioritize breast imaging services during periods of reduced capacity.

Airborne metals and polycyclic aromatic hydrocarbons in relation to mammographic breast density.

BACKGROUND: Breast density is strongly related to breast cancer. Identifying associations between environmental exposures and density may elucidate relationships with breast cancer. Metals and polycyclic aromatic hydrocarbons (PAHs) may influence breast density via oxidative stress or endocrine disruption. METHODS: Study participants (n = 222,581) underwent a screening mammogram in 2011 at a radiology facility in the Breast Cancer Surveillance Consortium. Zip code residential levels of airborne PAHs and metals (arsenic, cadmium, chromium, cobalt, lead, manganese, mercury, nickel, and selenium) were assessed using the 2011 EPA National Air Toxics Assessment. Breast density was measured using the Breast Imaging-Reporting and Data System (BI-RADS) lexicon. Logistic regression was used to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CI) for the individual air toxics and dense breasts (BI-RADS 3 or 4). Weighted quantile sum (WQS) regression was used to model the association between the air toxic mixture and density. RESULTS: Higher residential levels of arsenic, cobalt, lead, manganese, nickel, or PAHs were individually associated with breast density. Comparing the highest to the lowest quartile, higher odds of having dense breasts were observed for cobalt (OR = 1.60, 95% CI 1.56-1.64) and lead (OR = 1.56, 95% CI 1.52-1.64). Associations were stronger for premenopausal women. The WQS index was associated with density overall (OR = 1.22, 95% CI 1.20-1.24); the most heavily weighted air toxics were lead and cobalt. CONCLUSIONS: In this first study to evaluate the association between air toxics and breast density, women living in areas with higher concentrations of lead and cobalt were more likely to have dense breasts.

A Randomized Trial of External Practice Support to Improve Cardiovascular Risk Factors in Primary Care.

PURPOSE: We conducted a randomized controlled trial to compare the effectiveness of adding various forms of enhanced external support to practice facilitation on primary care practices' clinical quality measure (CQM) performance. METHODS: Primary care practices across Washington, Oregon, and Idaho were eligible if they had fewer than 10 full-time clinicians. Practices were randomized to practice facilitation only, practice facilitation and shared learning, practice facilitation and educational outreach visits, or practice facilitation and both shared learning and educational outreach visits. All practices received up to 15 months of support. The primary outcome was the CQM for blood pressure control. Secondary outcomes were CQMs for appropriate aspirin therapy and smoking screening and cessation. Analyses followed an intention-to-treat approach. RESULTS: Of 259 practices recruited, 209 agreed to be randomized. Only 42% of those offered educational outreach visits and 27% offered shared learning participated in these enhanced supports. CQM performance improved within each study arm for all 3 cardiovascular disease CQMs. After adjusting for differences between study arms, CQM improvements in the 3 enhanced practice support arms of the study did not differ significantly from those seen in practices that received practice facilitation alone (omnibus P = .40 for blood pressure CQM). Practices randomized to receive both educational outreach visits and shared learning, however, were more likely to achieve a blood pressure performance goal in 70% of patients compared with those randomized to practice facilitation alone (relative risk = 2.09; 95% CI, 1.16-3.76). CONCLUSIONS: Although we found no significant differences in CQM performance across study arms, the ability of a practice to reach a target level of performance may be enhanced by adding both educational outreach visits and shared learning to practice facilitation.

The Effect of Digital Breast Tomosynthesis Adoption on Facility-Level Breast Cancer Screening Volume.

OBJECTIVE: The purpose of this study was to determine whether digital breast tomosynthesis (DBT) adoption was associated with a decrease in screening mammography capacity across Breast Cancer Screening Consortium facilities, given concerns about increasing imaging and interpretation times associated with DBT. SUBJECTS AND METHODS: Facility characteristics and examination volume data were collected prospectively from Breast Cancer Screening Consortium facilities that adopted DBT between 2011 and 2014. Interrupted time series analyses using Poisson regression models in which facility was considered a random effect were used to evaluate differences between monthly screening volumes during the 12-month preadoption period and the 12-month postadoption period (with the two periods separated by a 3-month lag) and to test for changes in month-to-month facility-level screening volume during the preadoption and postadoption periods. RESULTS: Across five regional breast imaging registries, 15 of 83 facilities (18.1%) adopted DBT for screening between 2011 and 2014. Most had no academic affiliation (73.3% [11/15]), were nonprofit (80.0% [12/15]), and were general radiology practices (66.7% [10/15]). Facility-level monthly screening volumes were slightly higher during the postadoption versus preadoption periods (relative risk [RR], 1.09; 95% CI, 1.06-1.11). Monthly screening volumes remained relatively stable within the preadoption period (RR, 1.00 per month; 95% CI 1.00-1.01 per month) and the postadoption period (RR, 1.00; 95% CI, 1.00-1.01 per month). CONCLUSION: In a cohort of facilities with varied characteristics, monthly screening examination volumes did not decrease after DBT adoption.

Association between air pollution and mammographic breast density in the Breast Cancer Surveilance Consortium.

BACKGROUND: Mammographic breast density is a well-established strong risk factor for breast cancer. The environmental contributors to geographic variation in breast density in urban and rural areas are poorly understood. We examined the association between breast density and exposure to ambient air pollutants (particulate matter <2.5 µm in diameter (PM2.5) and ozone (O3)) in a large population-based screening registry. METHODS: Participants included women undergoing mammography screening at imaging facilities within the Breast Cancer Surveillance Consortium (2001-2009). We included women aged ≥40 years with known residential zip codes before the index mammogram (n = 279,967). Breast density was assessed using the American College of Radiology's Breast Imaging-Reporting and Data System (BI-RADS) four-category breast density classification. PM2.5 and O3 estimates for grids across the USA (2001-2008) were obtained from the US Environmental Protection Agency Hierarchical Bayesian Model (HBM). For the majority of women (94%), these estimates were available for the year preceding the mammogram date. Association between exposure to air pollutants and density was estimated using polytomous logistic regression, adjusting for potential confounders. RESULTS: Women with extremely dense breasts had higher mean PM2.5 and lower O3 exposures than women with fatty breasts (8.97 vs. 8.66 ug/m3 and 33.70 vs. 35.82 parts per billion (ppb), respectively). In regression analysis, women with heterogeneously dense vs. scattered fibroglandular breasts were more likely to have higher exposure to PM2.5 (fourth vs. first quartile odds ratio (OR) = 1.19, 95% confidence interval (CI) 1.16 - 1.23). Women with extremely dense vs. scattered fibroglandular breasts were less likely to have higher levels of ozone exposure (fourth vs. first quartile OR = 0.80, 95% CI 0.73-0.87). CONCLUSION: Exposure to PM2.5 and O3 may in part explain geographical variation in mammographic density. Further studies are warranted to determine the causal nature of these associations.

Factors Associated With Rates of False-Positive and False-Negative Results From Digital Mammography Screening: An Analysis of Registry Data.

BACKGROUND: Women screened with digital mammography may receive false-positive and false-negative results and subsequent imaging and biopsies. How these outcomes vary by age, time since the last screening, and individual risk factors is unclear. OBJECTIVE: To determine factors associated with false-positive and false-negative digital mammography results, additional imaging, and biopsies among a general population of women screened for breast cancer. DESIGN: Analysis of registry data. SETTING: Participating facilities at 5 U.S. Breast Cancer Surveillance Consortium breast imaging registries with linkages to pathology databases and tumor registries. PATIENTS: 405,191 women aged 40 to 89 years screened with digital mammography between 2003 and 2011. A total of 2963 were diagnosed with invasive cancer or ductal carcinoma in situ within 12 months of screening. MEASUREMENTS: Rates of false-positive and false-negative results and recommendations for additional imaging and biopsies from a single screening round; comparisons by age, time since the last screening, and risk factors. RESULTS: Rates of false-positive results (121.2 per 1000 women [95% CI, 105.6 to 138.7]) and recommendations for additional imaging (124.9 per 1000 women [CI, 109.3 to 142.3]) were highest among women aged 40 to 49 years and decreased with increasing age. Rates of false-negative results (1.0 to 1.5 per 1000 women) and recommendations for biopsy (15.6 to 17.5 per 1000 women) did not differ greatly by age. Results did not differ by time since the last screening. False-positive rates were higher for women with risk factors, particularly family history of breast cancer; previous benign breast biopsy result; high breast density; and, for younger women, low body mass index. LIMITATIONS: Confounding by variation in patient-level characteristics and outcomes across registries and regions may have been present. Some factors, such as numbers of first- and second-degree relatives with breast cancer and diagnoses associated with previous benign biopsy results, were not examined. CONCLUSION: False-positive mammography results and additional imaging are common, particularly for younger women and those with risk factors, whereas biopsies occur less often. Rates of false-negative results are low. PRIMARY FUNDING SOURCE: Agency for Healthcare Research and Quality and National Cancer Institute.

Multilevel factors associated with long-term adherence to screening mammography in older women in the U.S.

In the U.S., guidelines recommend that women continue mammography screening until at least age 74, but recent evidence suggests declining screening rates in older women. We estimated adherence to screening mammography and multilevel factors associated with adherence in a longitudinal cohort of older women. Women aged 66-75years receiving screening mammography within the Breast Cancer Surveillance Consortium were linked to Medicare claims (2005-2010). Claims data identified baseline adherence, defined as receiving subsequent mammography within approximately 2years, and length of time adherent to guidelines. Characteristics associated with adherence were investigated using logistic and Cox proportional hazards regression models. Analyses were stratified by age to investigate variation in relationships between patient factors and adherence. Among 49,775 women, 89% were adherent at baseline. Among women 66-70years, those with less than a high school education were more likely to be non-adherent at baseline (odds ratio [OR] 1.96; 95% confidence interval [CI] 1.65-2.33) and remain adherent for less time (hazard ratio [HR] 1.41; 95% CI 1.11-1.80) compared to women with a college degree. Women with ≥1 versus no Charlson co-morbidities were more likely to be non-adherent at baseline (OR 1.46; 95% CI 1.31-1.62) and remain adherent for less time (HR 1.44; 95% CI 1.24-1.66). Women aged 71-75 had lower adherence overall, but factors associated with non-adherence were similar. In summary, adherence to guidelines is high among Medicare-enrolled women in the U.S. receiving screening mammography. Efforts are needed to ensure that vulnerable populations attain these same high levels of adherence.

Comparing sensitivity and specificity of screening mammography in the United States and Denmark.

Delivery of screening mammography differs substantially between the United States (US) and Denmark. We evaluated whether there are differences in screening sensitivity and specificity. We included screens from women screened at age 50-69 years during 1996-2008/2009 in the US Breast Cancer Surveillance Consortium (BCSC) (n = 2,872,791), and from two population-based mammography screening programs in Denmark (Copenhagen, n = 148,156 and Funen, n = 275,553). Women were followed-up for 1 year. For initial screens, recall rate was significantly higher in BCSC (17.6%) than in Copenhagen (4.3%) and Funen (3.1%). Sensitivity was fairly similar in BCSC (91.8%) and Copenhagen (90.5%) and Funen (92.5%). At subsequent screens, recall rates were 8.8%, 1.8% and 1.4% in BCSC, Copenhagen and Funen, respectively. The BCSC sensitivity (82.3%) was lower compared with that in Copenhagen (88.9%) and Funen (86.9%), but when stratified by time since last screen, the sensitivity was similar. For both initial and subsequent screenings, the specificity of screening in BCSC (83.2% and 91.6%) was significantly lower than that in Copenhagen (96.6% and 98.8%) and Funen (97.9% and 99.2%). By taking time since last screen into account, it was found that American and Danish women had the same probability of having their asymptomatic cancers detected at screening. However, the majority of women free of asymptomatic cancers experienced more harms in terms of false-positive findings in the US than in Denmark.

Performance of digital screening mammography among older women in the United States.

BACKGROUND: Although healthy women aged 65 years have a life expectancy of 20 years, there is a paucity of data on the performance of digital screening mammography among these women. The authors examined the performance and outcomes of digital screening mammography among a national group of women aged ≥65 years. METHODS: From Breast Cancer Surveillance Consortium data for the years 2005 to 2011, the authors included 296,496 full-field digital screening mammograms among 133,042 women ages ≥65 years without a history of breast cancer. Sensitivity, specificity, positive predictive value (PPV1 ), recall rates, and 95% confidence intervals (95% CIs) were calculated across the spectrum of age and breast density. Multivariate logistic regression was used to compare mammography accuracy, cancer-detection rates (CDRs), and tumor characteristics by age and breast density. RESULTS: Multivariate analyses revealed a significant decrease in the recall rate with age (P for linear trend [Ptrend ] < .001) and significant increases in specificity, PPV1 , and CDR with age (Ptrend < .001, Ptrend < .001, and Ptrend = .01, respectively). Sensitivity did not vary significantly with age. Among women with cancer, the proportion with invasive disease increased with age from 76% at ages 65 to 74 years to 81% at ages ≥80 years. There was a higher proportion of late stage cancers and positive lymph nodes among women ages 65 to 74 years compared with women in the older age groups. CONCLUSIONS: The specificity, PPV1 , recall rate, and CDR of digital screening mammography improved with increased age. In addition, as age increased, the proportion of women with invasive versus ductal carcinoma in situ rose, whereas the proportion of women with positive lymph nodes decreased.

Breast cancer detection with short-interval follow-up compared with return to annual screening in patients with benign stereotactic or US-guided breast biopsy results.

PURPOSE: To compare the cancer detection rate and stage after benign stereotactic or ultrasonography (US)-guided core breast biopsy between patients with short-interval follow-up (SIFU) and those who return to annual screening. MATERIALS AND METHODS: The Breast Cancer Surveillance Consortium (BCSC) registry and the BCSC Statistical Coordinating Center received institutional review board approval for active and passive consent processes and a waiver of consent. All procedures were HIPAA compliant. BCSC data for 1994-2010 were used to compare ipsilateral breast cancer detection rates and tumor characteristics for diagnoses within 3 months after SIFU (3-8 months) versus return to annual screening (RTAS) mammography (9-18 months) after receiving a benign pathology result from image-guided breast biopsy. RESULTS: In total, 17 631 biopsies with benign findings were identified with SIFU or RTAS imaging. In the SIFU group, 27 ipsilateral breast cancers were diagnosed in 10 715 mammographic examinations (2.5 cancers per 1000 examinations) compared with 16 cancers in 6916 mammographic examinations in the RTAS group (2.3 cancers per 1000 examinations) (P = .88). Sixteen cancers after SIFU (59%; 95% confidence interval [CI]: 39%, 78%) were invasive versus 12 after RTAS (75%; 95% CI: 48%, 93%). The invasive cancer rate was 1.5 per 1000 examinations after SIFU (95% CI: 0.9, 2.4) and 1.7 per 1000 examinations (95% CI: 0.9, 3.0) after RTAS (P = .70). Among invasive cancers, 25% were late stage (stage 2B, 3, or 4) in the SIFU group (95% CI: 7%, 52%) versus 27% in the RTAS group (95% CI: 6%, 61%). Positive lymph nodes were found in seven (44%; 95% CI: 20%, 70%) invasive cancers after SIFU and in three (25%; 95% CI: 5%, 57%) invasive cancers after RTAS. CONCLUSION: Similar rates of cancer detection were found between SIFU and RTAS after benign breast biopsy with no significant differences in stage, tumor size, or nodal status, although the present study was limited by sample size. These findings suggest that patients with benign radiologic-pathologic-concordant percutaneous breast biopsy results could return to annual screening.

Supplemental magnetic resonance imaging plus mammography compared with magnetic resonance imaging or mammography by extent of breast density.

BACKGROUND: Examining screening outcomes by breast density for breast magnetic resonance imaging (MRI) with or without mammography could inform discussions about supplemental MRI in women with dense breasts. METHODS: We evaluated 52 237 women aged 40-79 years who underwent 2611 screening MRIs alone and 6518 supplemental MRI plus mammography pairs propensity score-matched to 65 810 screening mammograms. Rates per 1000 examinations of interval, advanced, and screen-detected early stage invasive cancers and false-positive recall and biopsy recommendation were estimated by breast density (nondense = almost entirely fatty or scattered fibroglandular densities; dense = heterogeneously/extremely dense) adjusting for registry, examination year, age, race and ethnicity, family history of breast cancer, and prior breast biopsy. RESULTS: Screen-detected early stage cancer rates were statistically higher for MRI plus mammography vs mammography for nondense (9.3 vs 2.9; difference = 6.4, 95% confidence interval [CI] = 2.5 to 10.3) and dense (7.5 vs 3.5; difference = 4.0, 95% CI = 1.4 to 6.7) breasts and for MRI vs MRI plus mammography for dense breasts (19.2 vs 7.5; difference = 11.7, 95% CI = 4.6 to 18.8). Interval rates were not statistically different for MRI plus mammography vs mammography for nondense (0.8 vs 0.5; difference = 0.4, 95% CI = -0.8 to 1.6) or dense breasts (1.5 vs 1.4; difference = 0.0, 95% CI = -1.2 to 1.3), nor were advanced cancer rates. Interval rates were not statistically different for MRI vs MRI plus mammography for nondense (2.6 vs 0.8; difference = 1.8 (95% CI = -2.0 to 5.5) or dense breasts (0.6 vs 1.5; difference = -0.9, 95% CI = -2.5 to 0.7), nor were advanced cancer rates. False-positive recall and biopsy recommendation rates were statistically higher for MRI groups than mammography alone. CONCLUSION: MRI screening with or without mammography increased rates of screen-detected early stage cancer and false-positives for women with dense breasts without a concomitant decrease in advanced or interval cancers.

Mammographic screening interval in relation to tumor characteristics and false-positive risk by race/ethnicity and age.

BACKGROUND: Biennial screening mammography retains most of the benefits of annual breast cancer screening with reduced harms. Whether screening guidelines based on race/ethnicity and age would be more effective than age-based guidelines is unknown. METHODS: Mammography data from the Breast Cancer Surveillance Consortium were linked to pathology and tumor databases. The authors identified women aged 40 to 74 years who underwent annual, biennial, or triennial screening mammography between 1994 and 2008. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (95% CI) of adverse tumor characteristics among 14,396 incident breast cancer cases and 10-year cumulative risks of false-positive recall and biopsy recommendation among 1,276,312 noncases. RESULTS: No increased risk of adverse tumor characteristics associated with biennial versus annual screening were noted in white women, black women, Hispanic women aged 40 to 49 years, or Asian women aged 50 to 74 years. Hispanic women aged 50 to 74 years who screened biennially versus annually were found to have an increased risk of late-stage disease (OR, 1.6; 95% CI, 1.0-2.5) and large tumors (OR, 1.6; 95% CI, 1.1-2.4). Asian women aged 40 to 49 years who underwent biennial screening had an elevated risk of positive lymph nodes (OR, 3.1; 95% CI, 1.3-7.1). No elevated risks were associated with triennial versus biennial screening. Cumulative false-positive risks decreased markedly with a longer screening interval. CONCLUSIONS: The authors found limited evidence of elevated risks of adverse tumor characteristics with biennial versus annual screening, whereas cumulative false-positive risks were lower. However, elevated risks of late-stage disease in Hispanic women and lymph node-positive disease in younger Asian women who screened less often than annually warrant consideration and replication.

Impact of mammography screening interval on breast cancer diagnosis by menopausal status and BMI.

BACKGROUND: Controversy remains regarding the frequency of screening mammography. Women with different risks for developing breast cancer because of body mass index (BMI) may benefit from tailored recommendations. OBJECTIVE: To determine the impact of mammography screening interval for women who are normal weight (BMI < 25), overweight (BMI 25-29.9), or obese (BMI ≥ 30), stratified by menopausal status. DESIGN: Two cohorts selected from the Breast Cancer Surveillance Consortium. Patient and mammography data were linked to pathology databases and tumor registries. PARTICIPANTS: The cohort included 4,432 women aged 40-74 with breast cancer; the false-positive analysis included a cohort of 553,343 women aged 40-74 without breast cancer. MAIN MEASURES: Stage, tumor size and lymph node status by BMI and screening interval (biennial vs. annual). Cumulative probability of false-positive recall or biopsy by BMI and screening interval. Analyses were stratified by menopausal status. KEY RESULTS: Premenopausal obese women undergoing biennial screening had a non-significantly increased odds of a tumor size > 20 mm relative to annual screeners (odds ratio [OR] = 2.07; 95 % confidence interval [CI] 0.997 to 4.30). Across all BMI categories from normal to obese, postmenopausal women with breast cancer did not present with higher stage, larger tumor size or node positive tumors if they received biennial rather than annual screening. False-positive recall and biopsy recommendations were more common among annually screened women. CONCLUSION: The only negative outcome identified for biennial vs. annual screening was a larger tumor size (> 20 mm) among obese premenopausal women. Since annual mammography does not improve stage at diagnosis compared to biennial screening and false-positive recall/biopsy rates are higher with annual screening, women and their primary care providers should weigh the harms and benefits when deciding on annual versus biennial screening.