Chapter IV. Reduced breast-cancer mortality with mammography screening-an assessment of currently available data

To evaluate, by analysis of breast cancer mortality data from all the 26 Swedish counties for the years 1971 to 1990, whether the effect of the introduction of mammography screening in Sweden can be assessed by observation from existing mortality data. A Poisson regression model was used to study whether a decrease in breast cancer mortality among women aged 50–74 years was associated with the extent of mammography screening in different counties and periods. In regions where mammography screening had been introduced, breast cancer mortality tended to be decreased, on average, compared with regions with-'out screening. If a 10 year time lag between the start of screening and its full effect on mortality is assumed then the estimated reduction in breast cancer mortality associated with introduction of screening was 19% with a 95% confidence interval ranging from 3% to 37%. The results suggest that the effect of mammography screening may be studied using existing routine mortality data and appropriate statistical modelling. This way of assessing the outcome of the screening is valuable when continuously monitoring a screening programme that has become a public health routine.

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Impact of Mammography Screening Rates on Breast Cancer Mortality in Nevada (NV), California (CA) and US: Implications for Health Care Policy

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/j.ijrobp.2018.07.1203 ◽

2018 ◽

Vol 102 (3) ◽

pp. e409

Author(s):

P. Kumar ◽

C. Cross ◽

J. De Leon ◽

S. Moonie

Keyword(s):

Breast Cancer ◽

Health Care ◽

Cancer Mortality ◽

Mammography Screening ◽

Health Care Policy ◽

Breast Cancer Mortality ◽

Care Policy

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Worldwide Review and Meta-Analysis of Cohort Studies Measuring the Effect of Mammography Screening Programmes on Incidence-Based Breast Cancer Mortality

Cancers ◽

10.3390/cancers12040976 ◽

2020 ◽

Vol 12 (4) ◽

pp. 976

Author(s):

Amanda Dibden ◽

Judith Offman ◽

Stephen W. Duffy ◽

Rhian Gabe

Keyword(s):

Breast Cancer ◽

Cancer Screening ◽

Breast Cancer Screening ◽

Cancer Mortality ◽

Mammography Screening ◽

Meta Analysis ◽

Breast Cancer Mortality ◽

Substantial Reduction ◽

Healthcare Setting ◽

Actual Attendance

In 2012, the Euroscreen project published a review of incidence-based mortality evaluations of breast cancer screening programmes. In this paper, we update this review to October 2019 and expand its scope from Europe to worldwide. We carried out a systematic review of incidence-based mortality studies of breast cancer screening programmes, and a meta-analysis of the estimated effects of both invitation to screening and attendance at screening, with adjustment for self-selection bias, on incidence-based mortality from breast cancer. We found 27 valid studies. The results of the meta-analysis showed a significant 22% reduction in breast cancer mortality with invitation to screening, with a relative risk of 0.78 (95% CI 0.75–0.82), and a significant 33% reduction with actual attendance at screening (RR 0.67, 95% CI 0.61–0.75). Breast cancer screening in the routine healthcare setting continues to confer a substantial reduction in mortality from breast cancer.

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Race-Specific Impact of Natural History, Mammography Screening, and Adjuvant Treatment on Breast Cancer Mortality Rates in the United States

Breast Diseases A Year Book Quarterly ◽

10.1016/j.breastdis.2011.10.028 ◽

2011 ◽

Vol 22 (4) ◽

pp. 362-364

Author(s):

K.A. Dookeran

Keyword(s):

Breast Cancer ◽

United States ◽

Natural History ◽

Adjuvant Treatment ◽

Cancer Mortality ◽

Mammography Screening ◽

Breast Cancer Mortality ◽

The United States ◽

Mortality Rates ◽

Specific Impact

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Realisation of mammography screening in Khanty-Mansiysk Autonomous State – Yugra

Tumors of female reproductive system ◽

10.17650/1994-4098-2020-16-3-32-36 ◽

2021 ◽

Vol 16 (3) ◽

pp. 32-36

Author(s):

Ju. A. Belaya ◽

N. A. Zakharova ◽

A. R. Brentnall

Keyword(s):

Breast Cancer ◽

Cancer Mortality ◽

Mammography Screening ◽

Breast Cancer Mortality ◽

Target Population ◽

Mammographic Screening ◽

Detection Sensitivity ◽

Mortality And Morbidity ◽

Screening Performance ◽

State Region

Objective: to perform a retrospective analysis of the quality of mammography screening in Khanty-Mansiysk State Region – Yugra from its beginning to 2018 inclusive.Materials and methods. During this investigation a throughout analysis of epidemiological indicators (breast cancer mortality and morbidity), quality indicators (coverage of the target population, cancer detection in general and early detection, sensitivity and morbidity) and mammographic screening performance indicators (projected and observed morbidity and mortality) was carried out.Results and conclusions. During this period, 572,348 women were screened, 9.7 % of whom were recommended for further screening. The coverage of the target population for one round was 33 %. Screening test sensitivity for the specified period was 80 %. The observed number of women with newly detected breast cancer cases of stage I in 2018 made 42 % (53 cases) higher in comparison with expected numbers, and in stage T2+ it made 21 % (62 cases) less. The observed number of deaths in 2018 was 23.7 % lower than expected. The above-mentioned demonstrates once again that mammography screening in Khanty-Mansiysk State Region – Yugra has led to the improvement of early diagnosis of breast cancer. This, in turn, leads to a steady decline in breast cancer mortality among women over 40 years of age.

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Breast cancer mortality and screening mammography in New Zealand: Incidence-based and aggregate analyses

Journal of Medical Screening ◽

10.1177/0969141318776039 ◽

2018 ◽

Vol 26 (1) ◽

pp. 35-43 ◽

Cited By ~ 1

Author(s):

Richard Taylor ◽

Marli Gregory ◽

Kerry Sexton ◽

Jessica Wharton ◽

Nisha Sharma ◽

...

Keyword(s):

Breast Cancer ◽

New Zealand ◽

Cancer Mortality ◽

Mammography Screening ◽

Breast Cancer Mortality ◽

Primary Treatment ◽

Screening Mammography ◽

Randomized Controlled ◽

Before And After ◽

Incident Cases

Objective To investigate trends in breast cancer mortality in New Zealand women, to corroborate or negate a causal association with service screening mammography. Method Cumulated mortality rates from breast cancer deaths individually linked to incident cases diagnosed before and after screening commencement were compared, in women aged 50–64 (from 2001) and aged 45–49 and 65–69 (from 2006). Trends and differences in aggregate invasive breast cancer mortality (1975–2013) were assessed in relation to introduction of mammography screening targeting women aged 50–64 and 45–69. Joinpoint analysis was also undertaken. Results The reduction in incidence-based cumulated breast cancer mortality before and after the introduction of screening was −15% (p = 0.006) for women aged 45–69, and 17% (p = 0.005) for those aged 50–64. Aggregate mortality declined by −34% (2005–13 compared with 1992–98) in the age group 50–64, and by –28% among women aged 45–49 and –25% among women aged 65–74. For women aged 50–64 the 2-joinpoint model shows a 1990 turning point, from prior rising mortality to a mean −1.8% decline per annum, coinciding with improvements in primary treatment of breast cancer; and a steepening of the decline (−3.0% p.a.) from the late 1990s, coinciding with the introduction of service mammography screening. Conclusion Breast cancer mortality declines occurring since the advent of screening mammography in New Zealand are consistent with other incidence-based and aggregate studies of screening mammography in populations, individual-based cohort studies, and randomized controlled trials.

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Participation in Mammography Screening Accomplishes an Enduring and Significant Reduction in Breast Cancer Mortality in the Era of Modern Therapy: An Observational Study Spanning 52 Years

Journal of Global Oncology ◽

10.1200/jgo.18.73200 ◽

2018 ◽

Vol 4 (Supplement 2) ◽

pp. 56s-56s

Author(s):

R. Smith ◽

Keyword(s):

Breast Cancer ◽

Early Detection ◽

Cancer Mortality ◽

Mammography Screening ◽

Breast Cancer Mortality ◽

Mortality Rates ◽

Trial Period ◽

Breast Cancer Death ◽

Self Selection ◽

Screening Trial

Background: A significant decrease in breast cancer mortality has been demonstrated in populations invited to mammography screening. There have been questions regarding the value of mammography in the era of modern therapies, and the relative contribution of mammography screening and modern therapy on mortality reduction. Aim: We have sought to clarify the extent to which early detection through mammography screening contributes to the reduction of breast cancer death in the era of modern adjuvant therapies. We address this question by studying five decades of continuous data from a stable population spanning the pre- and postscreening and adjuvant therapy periods. Methods: We analyzed changes in breast cancer mortality in a stable population in Dalarna County, Sweden, among women aged 40-69 years during the 52 years from 1964 through 2015. Mortality data were obtained from the National Cause of Death Register in Sweden, and incidence data from the Swedish National Cancer Registry. Crude and incidence-based mortality rates were compared among four successive 13-year periods: the prescreening period from 1964 through 1976, the Swedish Two-County randomized screening trial period from 1977 through 1989, and two service screening periods from 1990-2002 and from 2003-2015. Furthermore, we measured the effect of early detection upon breast cancer mortality in women exposed to mammography screening by comparison with breast cancer death in women not exposed to mammography screening, within these three screening periods. Data were analyzed by Poisson regression, with corrections for lead time and self-selection bias. Results: There were 5844 incident cases and 1425 breast cancer deaths during the 52 years of observation. The relative breast cancer mortality rates associated with exposure to screening, adjusted for self-selection bias, were 0.46 (95% CI 0.30-0.69) in the trial period (1977-1989), 0.44 (95% CI 0.30-0.65) in the 1990-2002 period, and 0.37 (95% CI 0.24-0.56) in the 2003-2015 period. The significant reductions in incidence-based breast cancer mortality associated with exposure to screening were independent of contemporaneous changes in therapy. Conclusion: The combination of early detection of breast cancer through mammography screening and the resultant earlier treatment has significantly reduced breast cancer mortality in Dalarna County in the women exposed to screening, compared with the women not participating in screening, by a factor of 2.2 in the screening trial period, increasing to a factor of 2.7 in the most recent service screening period. These mortality benefits can be attributed to the far greater effectiveness of modern therapeutic methods upon cancers detected at screening compared with the poorer effectiveness of the same therapeutic methods in women not participating in screening.

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