Interpreting Overdiagnosis Estimates in Population-based Mammography Screening

Estimates of overdiagnosis in mammography screening range from 1% to 54%. This review explains such variations using gradual implementation of mammography screening in the Netherlands as an example. Breast cancer incidence without screening was predicted with a micro-simulation model. Observed breast cancer incidence (including ductal carcinoma in situ and invasive breast cancer) was modeled and compared with predicted incidence without screening during various phases of screening program implementation. Overdiagnosis was calculated as the difference between the modeled number of breast cancers with and the predicted number of breast cancers without screening. Estimating overdiagnosis annually between 1990 and 2006 illustrated the importance of the time at which overdiagnosis is measured. Overdiagnosis was also calculated using several estimators identified from the literature. The estimated overdiagnosis rate peaked during the implementation phase of screening, at 11.4% of all predicted cancers in women aged 0–100 years in the absence of screening. At steady-state screening, in 2006, this estimate had decreased to 2.8%. When different estimators were used, the overdiagnosis rate in 2006 ranged from 3.6% (screening age or older) to 9.7% (screening age only). The authors concluded that the estimated overdiagnosis rate in 2006 could vary by a factor of 3.5 when different denominators were used. Calculations based on earlier screening program phases may overestimate overdiagnosis by a factor 4. Sufficient follow-up and agreement regarding the chosen estimator are needed to obtain reliable estimates

Communication about colorectal cancer screening in Britain:public preferences for an expert recommendation

BACKGROUND: Informed decision-making approaches to cancer screening emphasise the importance of decisions being determined by individuals' own values and preferences. However, advice from a trusted source may also contribute to autonomous decision-making. This study examined preferences regarding a recommendation from the NHS and information provision in the context of colorectal cancer (CRC) screening. METHODS: In face-to-face interviews, a population-based sample of adults across Britain (n=1964; age 50–80 years) indicated their preference between: (1) a strong recommendation to participate in CRC screening, (2) a recommendation alongside advice to make an individual decision, and (3) no recommendation but advice to make an individual decision. Other measures included trust in the NHS and preferences for information on benefits and risks. RESULTS: Most respondents (84%) preferred a recommendation (47% strong recommendation, 37% recommendation plus individual decision-making advice), but the majority also wanted full information on risks (77%) and benefits (78%). Men were more in favour of a recommendation than women (86% vs 81%). Trust in the NHS was high overall, but the minority who expressed low trust were less likely to want a recommendation. CONCLUSION: Most British adults want full information on risks and benefits of screening but they also want a recommendation from an authoritative source. An ‘expert' view may be an important part of autonomous health decision-making

Clinical impact of additional findings detected by genome-wide non-invasive prenatal testing:Follow-up results of the TRIDENT-2 study

In the TRIDENT-2 study, all pregnant women in the Netherlands are offered genome-wide non-invasive prenatal testing (GW-NIPT) with a choice of receiving either full screening or screening solely for common trisomies. Previous data showed that GW-NIPT can reliably detect common trisomies in the general obstetric population and that this test can also detect other chromosomal abnormalities (additional findings). However, evidence regarding the clinical impact of screening for additional findings is lacking. Therefore, we present follow-up results of the TRIDENT-2 study to determine this clinical impact based on the laboratory and perinatal outcomes of cases with additional findings. Between April 2017 and April 2019, additional findings were detected in 402/110,739 pregnancies (0.36%). For 358 cases, the origin was proven to be either fetal (n = 79; 22.1%), (assumed) confined placental mosaicism (CPM) (n = 189; 52.8%), or maternal (n = 90; 25.1%). For the remaining 44 (10.9%), the origin of the aberration could not be determined. Most fetal chromosomal aberrations were pathogenic and associated with severe clinical phenotypes (61/79; 77.2%). For CPM cases, occurrence of pre-eclampsia (8.5% [16/189] vs 0.5% [754/159,924]; RR 18.5), and birth weigh

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

Background: The optimal interval between two consecutive mammograms is uncertain. The UK Frequency Trial did not show a significant difference in breast cancer mortality between screening every year (study group) and screening every 3 years (control group). In this study, the trial is simulated in order to gain insight into the results of the trial and to predict the effect of different screening intervals on breast cancer mortality. Methods: UK incidence, life tables and information from the trial were used in the microsimulation model MISCAN-Fadia to simulate the trial and predict the number of breast ca

Impact of different age ranges on the benefits and harms of the breast cancer screening programme by the EU-TOPIA tool

BackgroundThe recommendation for the implementation of mammography screening in women aged 45–49 and 70–74 is conditional with moderate certainty of the evidence. The aim of this study is to simulate the long-term outcomes (2020–50) of using different age range scenarios in the breast cancer screening programme of the Valencia Region (Spain), considering different programme participation rates.MethodsThree age range scenarios (S) were simulated with the EU-TOPIA tool, considering a biennial screening interval: S1, 45–69 years old (y); S2, 50–69 y and S3, 45–74 y. Simulations were performed for four participation rates: A = current participation (72.7%), B = +5%, C = +10% and D = +20%. Considered benefits: number (N°) of in situ and invasive breast cancers (BC) (screen vs. clinically detected), N° of BC deaths and % BC mortality reduction. Considered harms: N° of false positives (FP) and % overdiagnosis.ResultsThe results showed that BC mortality decreased in all scenarios, being higher in S3A (32.2%) than S1A (30.6%) and S2A (27.9%). Harms decreased in S2A vs. S1A (N° FP: 236 vs. 423, overdiagnosis: 4.9% vs. 5.0%) but also benefits (BC mortality reduction: 27.9% vs. 30.6%, N° screen-detected invasive BC 15/28 vs. 18/25). In S3A vs. S1A, an increase in benefits was observed (BC mortality reduction: 32.2% vs. 30.6%), N° screen-detected in situ B: 5/2 vs. 4/3), but also in harms (N° FP: 460 vs. 423, overdiagnosis: 5.8% vs. 5.0%). Similar trends were observed with increased participation.ConclusionsAs the age range increases, so does not only the reduction in BC mortality, but also the probability of FP and overdiagnosis

Effect of exercise therapy in patients with hip osteoarthritis: A systematic review and cumulative meta-analysis

OBJECTIVE: To evaluate the existing evidence on the effect of exercise therapy in patients with hip osteoarthritis (OA) compared to no treatment and explore whether a further trial will change the current evidence. DESIGN: Systematic review and cumulative meta-analysis using randomized controlled trials (RCT) to determine the effect on pain and function post-treatment, and at 6-9 months after treatment. Standardized mean difference (SMD) ​≤ ​-0.37 was considered clinically worthwhile. Extended funnel plots were used to simulate the impact of a new trial on the pooled effect size of pain and function. RESULTS: 18 RCTs were included. Post-treatment we found a beneficial effect of exercise therapy on pain (SMD -0.38, 95% Confidence Interval (CI): 0.55 to -0.22) and function (SMD -0.31, 95% CI -0.49 to -0.11). A beneficial effect of exercise therapy on pain (SMD -0.23, 95% CI: 0.41 to -0.05) and function (SMD -0.29, 95% CI: 0.45 to -0.12) was found 6-9 months after treatment. Most effect estimates were small, and it is unclear whether these are clinically meaningful. Extended funnel plots and a simulation of a new trial showed that only a new trial with a larger effect than the current pooled effect or a trial including 74,843 participants would change the pooled effect estimate from an unclear to a clearly clinically worthwhile effect. CONCLUSIONS: We found a beneficial effect of exercise therapy on pain and function in hip OA. It is unlikely a new trial added to current evidence will change the conclusion

Personalizing age of cancer screening cessation based on comorbid conditions: Model estimates of harms and benefits

Background: Harms and benefits of cancer screening depend on age and comorbid conditions, but reliable estimates are lacking. Objective: To estimate the harms and benefits of cancer screening by age and comorbid conditions to inform decisions about screening cessation. Design: Collaborative modeling with 7 cancer simulation models and common data on average and comorbid condition level-specific life expectancy. Setting: U.S. population. Patients: U.S. cohorts aged 66 to 90 years in 2010 with average health or 1 of 4 comorbid condition levels: none, mild, moderate, or severe. Intervention: Mammography, prostate-specific antigen testing, or fecal immunochemical testing. Measurements: Lifetime cancer deaths prevented and life-years gained (benefits); false-positive test results and overdiagnosed cancer cases (harms). For each comorbid condition level, the age at which harms and benefits of screening were similar to that for persons with average health having screening at age 74 years. Results: Screening 1000 women with average life expectancy at age 74 years for breast cancer resulted in 79 to 96 (range across models) false-positive results, 0.5 to 0.8 overdiagnosed cancer cases, and 0.7 to 0.9 prevented cancer deaths. Although absolute numbers of harms and benefits differed across cancer sites, the ages at which to cease screening were consistent across models and cancer sites. For persons with no, mild, moderate, and severe comorbid conditions, screening until ages 76, 74, 72, and 66 years, respectively, resulted in harms and benefits similar to average-health persons. Limitation: Comorbid conditions influenced only life expectancy. Conclusion: Comorbid conditions are an important determinant of harms and benefits of screening. Estimates of screening benefits and harms by comorbid condition can inform discussions between providers and patients about personalizing screening cessation decisions

Tipping the Balance of Benefits and Harms to Favor Screening Mammography Starting at Age 40 Years A Comparative Modeling Study of Risk

Background: Timing of initiation of screening for breast cancer is controversial in the United States. Objective: To determine the threshold relative risk (RR) at which the harm-benefit ratio of screening women aged 40 to 49 years equals that of biennial screening for women aged 50 to 74 years. Design: Comparative modeling study. Data Sources: Surveillance, Epidemiology, and End Results program, Breast Cancer Surveillance Consortium, and medical literature. Target Population: A contemporary cohort of women eligible for routine screening. Time Horizon: Lifetime. Perspective: Societal. Intervention: Mammography screening starting at age 40 versus 50 years with different screening methods (film, digital) and screening intervals (annual, biennial). Outcome Measures: Benefits: life-years gained, breast cancer deaths averted; harms: false-positive mammography findings; harm-benefit ratios: false-positive findings/life-years gained, false-positive findings/deaths averted. Results of Base-Case Analysis: Screening average-risk women aged 50 to 74 years biennially yields the same false-positive findings/life-years gained as biennial screening with digital mammography starting at age 40 years for women with a 2-fold increased risk above average (median threshold RR, 1.9 [range across models, 1.5 to 4.4]). The threshold RRs are higher for annual screening with digital mammography (median, 4.3 [range, 3.3 to 10]) and when false-positive findings/deaths averted is used Results of Sensitivity Analysis: The threshold RRs changed slightly when a more comprehensive measure of harm was used and were relatively insensitive to lower adherence assumptions. Limitation: Risk was assumed to influence onset of disease without influencing screening performance. Conclusion: Women aged 40 to 49 years with a 2-fold increased risk have similar harm-benefit ratios for biennial screening mammography as average-risk women aged 50 to 74 years. Threshold RRs required for favorable harm-benefit ratios vary by screening method, interval, and outcome measure

Benefits, Harms, and Costs for Breast Cancer Screening After US Implementation of Digital Mammography

Background Compared with film, digital mammography has superior sensitivity but lower specificity for women aged 40 to 49 years and women with dense breasts. Digital has replaced film in virtually all US facilities, but overall population health and cost from use of this technology are unclear. Methods Using five independent models, we compared digital screening strategies starting at age 40 or 50 years applied annually, biennially, or based on density with biennial film screening from ages 50 to 74 years and with no screening. Common data elements included cancer incidence and test performance, both modified by breast density. Lifetime outcomes included mortality, quality-adjusted life-years, and screening and treatment costs. Results For every 1000 women screened biennially from age 50 to 74 years, switching to digital from film yielded a median within-model improvement of 2 life-years, 0.27 additional deaths averted, 220 additional false-positive results, and $0.35 million more in costs. For an individual woman, this translates to a health gain of 0.73 days. Extending biennial digital screening to women ages 40 to 49 years was cost-effective, although results were sensitive to quality-of-life decrements related to screening and false positives. Targeting annual screening by density yielded similar outcomes to targeting by age. Annual screening approaches could increase costs to$5.26 million per 1000 women, in part because of higher numbers of screens and false positives, and were not efficient or cost-effective. Conclusions The transition to digital breast cancer screening in the United States increased total costs for small added health benefits. The value of digital mammography screening among women aged 40 to 49 years depends on women's preferences regarding false positives