Consequences of a National Mammography Screening Program on Diagnostic Procedures and Tumor Sizes in Breast Cancer. A Retrospective Study of 1540 Cases Diagnosed and Histologically Confirmed Between 1995 and 1997

Objective In mammography screening, interval cancers present a problem. The metric ‘screening sensitivity’ monitors both how well a programme detects cancers and avoids interval cancers. To our knowledge, the effect of breast cancer surrogate molecular subtypes on screening sensitivity has never been evaluated. We aimed to measure the 2-year screening sensitivity according to breast cancer subtypes. Methods We studied 734 women with an invasive breast cancer diagnosed between 2003 and 2007 after participating in one regional division of Quebec’s Mammography Screening Program. They represented 83% of all participating women with an invasive BC diagnosis in that region for that period. Tumours were categorized into ‘luminal A-like’, ‘luminal B-like’, ‘triple-negative’ and ‘HER2-positive’ subtypes. We used logistic regression and marginal standardization to estimate screening sensitivity, sensitivity ratios (SR) and sensitivity differences. We also assessed the mediating effect of grade. Results Adjusted 2-year screening sensitivity was 75.4% in luminal A-like, 66.1% in luminal B-like, 52.9% in triple-negative and 45.3% in HER2-positive, translating into sensitivity ratios of 0.88 (95% confidence interval [CI] = 0.78–0.98) for luminal B-like, 0.70 (CI = 0.56–0.88) for triple-negative and 0.60 (CI = 0.39–0.93) for HER2-positive, when compared with luminal A-like. Grade entirely mediated the subtype-sensitivity association for triple negative and mediated it partly for HER2-positive. Screening round (prevalent vs. incident) did not modify results. Conclusion There was substantial variation in screening sensitivity according to breast cancer subtypes. Aggressive phenotypes showed the lowest sensitivity, an effect that was mediated by grade. Tailoring screening according to women’s subtype risk factors might eventually lead to more efficient programs.

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Incidence of breast cancer and estimates of overdiagnosis after the initiation of a population-based mammography screening program

Canadian Medical Association Journal ◽

10.1503/cmaj.121791 ◽

2013 ◽

Vol 185 (10) ◽

pp. E492-E498 ◽

Cited By ~ 30

Author(s):

A. Coldman ◽

N. Phillips

Keyword(s):

Breast Cancer ◽

Mammography Screening ◽

Screening Program ◽

Population Based ◽

Mammography Screening Program

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Breast cancer screening program in Lithuania: trends in breast cancer mortality before and during the introduction of the mammography screening programme

Acta medica Lituanica ◽

10.15388/amed.2020.27.2.3 ◽

2020 ◽

Vol 28 (2) ◽

pp. 20-28

Author(s):

Laura Steponavičienė ◽

Rūta Briedienė ◽

Rasa Vansevičiūtė-Petkevičienė ◽

Daiva Gudavičienė ◽

Ieva Vincerževskienė

Keyword(s):

Breast Cancer ◽

Cancer Mortality ◽

Mammography Screening ◽

Screening Program ◽

Breast Cancer Mortality ◽

Target Population ◽

Population Based ◽

Cancer Awareness ◽

Cancer Screening Program ◽

Mammography Screening Program

BackgroundBreast cancer is the most frequent oncological disease as well as the leading cause of cancer death among women worldwide. Decline in mortality in economically strong countries is observed. This decline is mostly related to early diagnosis (improvement in breast cancer awareness and mammography screening program (MSP)) and more effective treatment. In the end of 2005, the MSP started in Lithuania. The main aim of this article was to evaluate breast cancer mortality during 22 years in Lithuania, as well as changes before the start of the MSP and during its implementation, in order to assess the influence of the MSP on mortality. Materials and MethodsAnalysis was based on data from the population-based Lithuanian Cancer Registry. Analysis of changes in mortality included the period from 1998 to 2019. Age standardized mortality rates were calculated for assessment of changes. Join-point regression analysis was used. ResultsApplying the segmental regression model, it was found that during the study period mortality was statistically significantly decreasing by -1.1% each year. Mortality among women under the age of 50 decreased both before and during the implementation of MSP. Mortality in the target population also was already decreasing until the implementation of the program, but since 2006 significant reduction in mortality was observed in this group. ConclusionsOverall breast cancer mortality is decreasing in Lithuania. After the implementation of MSP the largest reduction in mortality was observed among the target population, however, it is not as pronounced as it could be with the well-organized MSP.

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Mortality reduction in the Swedish mammography screening program.

Journal of Clinical Oncology ◽

10.1200/jco.2011.29.27_suppl.29 ◽

2011 ◽

Vol 29 (27_suppl) ◽

pp. 29-29

Author(s):

P. H. Zahl ◽

J. Mæhlen

Keyword(s):

Breast Cancer ◽

Cancer Mortality ◽

Mammography Screening ◽

Screening Program ◽

Breast Cancer Mortality ◽

Test Group ◽

Control Group ◽

Mortality Reduction ◽

Mammography Screening Program

29 Background: The introduction of a nationwide mammography screening program in Sweden in 1986 was associated with a 50% persistent increase of breast cancer incidence (including carcinoma in situ). Whether screening has been instrumental in a recent decline in the breast cancer mortality remains an open question. Methods: We compared the 18 years breast cancer mortality for two groups of women; those diagnosed in the first 6 years of the screening program and those diagnosed during a 6 year period that included the last 4 years before screening started and the first 2 years of the screening program. The test group (n + 328,927) included women aged 40 to 69 at the first invitation to screening. On average the women in the age-matched control group (n + 317,404) were born 4 years earlier then the women in the test group. The numbers of incident invasive breast cancers in each county were obtained from the Swedish Cancer Registry (in-situ cancers were excluded) and the corresponding breast cancer deaths were obtained from the Swedish Causes of Death Registry. Results: After 18 years follow up, the mortality reduction was 14% in the test group. However, most of this difference (10%) occurred in the first five years after diagnosis reflecting improved medical treatment of breast cancer. Most of the 14% difference also disappeared if we adjusting for period effects. Conclusions: About 83% of women in the test group were also included in the control group making the two groups almost identical with respect to risk variables. By screening the control group at the end of a 6-year period, the results are adjusted for differences due to lead-time bias and by studying mortality instead of survival overdiagnosis (length time bias) is also adjusted for. We conclude that organized mammography screening is not an important cause for the reduction in the breast cancer mortality in Sweden.

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First Breast Cancer Mammography Screening Program in Mexico: Initial Results 2005-2006

The Breast Journal ◽

10.1111/j.1524-4741.2009.00811.x ◽

2009 ◽

Vol 15 (6) ◽

pp. 623-631 ◽

Cited By ~ 26

Author(s):

Sergio Rodríguez-Cuevas ◽

Fernando Guisa-Hohenstein ◽

Sonia Labastida-Almendaro

Keyword(s):

Breast Cancer ◽

Mammography Screening ◽

Screening Program ◽

Mammography Screening Program ◽

Initial Results

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Trends in Breast Cancer Incidence and Stage Distribution Before and During the Introduction of the Mammography Screening Program in Lithuania

Cancer Control ◽

10.1177/1073274818821096 ◽

2019 ◽

Vol 26 (1) ◽

pp. 107327481882109 ◽

Cited By ~ 5

Author(s):

Laura Steponaviciene ◽

Ruta Briediene ◽

Rasa Vanseviciute ◽

Giedre Smailyte

Keyword(s):

Breast Cancer ◽

Mammography Screening ◽

Screening Program ◽

Breast Cancer Incidence ◽

Age Groups ◽

Target Population ◽

Steady Increase ◽

Incidence Trends ◽

Implementation Period ◽

Mammography Screening Program

Background: The aim of this study was to analyze the incidence trends of localized and advanced breast cancer (BC) before and during the implementation of the mammography screening program (MSP) in Lithuania. Methods: The study period was divided into 2 intervals: the prescreening period (1998-2005) and implementation period (2006-2012). Analysis was performed for 3 age-groups: 0 to 49 years, 50 to 69 (target population), and older than 70. Results: In all age-groups, the incidence of localized BC has shown a steady increase, while the incidence of advanced stage BC has decreased. In the target population, during the study period, the stage I BC incidence increased statistically significantly by 10.3% per year (from 3.3 per 100 000 in 1998 to 12.2 per 100 000 in 2012). The increase in localized BC was faster in the period before the implementation of the MSP than during the implementation in 2006 to 2012 (10.3% and 5.7%). A slightly statistically significant decrease was observed for advanced BC during the study period (−1.1% per year), while during the implementation of the MSP, significant changes were not seen. Conclusions: The results of our study indicate that the implementation of the MSP in Lithuania did not significantly influence trends of localized and advanced BC. Changes observed during the study period, including the prescreening and screening introduction periods, may reflect the general trends in the awareness of BC and improvements in diagnostics.

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