[Systematic and quality-assured early diagnosis of sporadic breast cancer : Update on screening effects and scientific studies]. / Systematische und qualitätsgesicherte Früherkennung des sporadischen Mammakarzinoms : Update Screening-Effekte und wissenschaftliche Studien.

BACKGROUND: A quality-assured mammography screening programme has been available since 2009, nationwide, to all women in Germany between the ages of 50 and 69. The programme is based on the European Guidelines. In this review article the authors summarize the current status of scientific assessments of this national early detection programme for breast cancer and provide an outlook regarding ongoing studies on effectiveness tests and further development. RESULTS: We expect a decline in mortality rates relating to breast cancer as a result of successfully bringing diagnoses forward and a decrease in advanced breast cancer after a repeated screening. The extent will be shown in the current ZEBra study on mortality evaluation. CONCLUSION: Potential for a further increase in the effectiveness of the systematic early detection of breast cancer can be identified in four areas: (1) More women should take advantage of the early detection opportunities offered by the medical insurance funds; so far, on average, only about 50% of the women between 50 and 69 who are entitled to a screening examination actually take part in the programme. (2) Entitlement to take part in the programme should be extended to women over 70. (3) The further development of digital mammography towards digital breast tomosynthesis promises to reduce the number of false positive recalls while at the same time increasing sensitivity. (4) There should be scientific studies relating to an extension of screening strategies for the small number of women in the entitlement range who have extremly dense breasts.

Incidence of advanced-stage breast cancer in regular participants of a mammography screening program: a prospective register-based study.

BACKGROUND: The European Guidelines for breast cancer screening suggest that the impact of population-based mammography screening programmes (MSP) may be assessed using the relative reduction in the incidence of advanced breast cancer (ABC, that is, stage UICC II and higher) as a surrogate indicator of screening effectiveness. METHODS: This prospective, population register-based study contained individual data of 1,200,246 women (aged 50-69 years) who attended the initial prevalence screening between 2005 and 2009. Of them, 498,029 women returned for the regular (i.e., within 24 months) first subsequent, and 208,561 for the regular second subsequent incidence screenings. The incidence rate of ABC was calculated for the 24-months period following, but not including, the initial screening by incorporating all interval ABCs and all ABCs detected at the regular first incidence screening; the ABC rate for the second 24-months period was determined in the same way, including ABCs detected in the interval after the first and, respectively, at the second incidence screening. The relative reduction in the ABC incidence was derived by comparing the age-standardized rates in these two periods with an age-standardized reference incidence rate, observed in the target population before the MSP implementation. The strengths and weaknesses of this particular study design were contrasted with a recently published checklist of main methodological problems affecting studies of the effect of MSP on ABC incidence. RESULTS: The age-standardized ABC incidence rate was 291.6 per 100,000 women for the 24-months period subsequent to the initial screening, and 275.0/100,000 for the 24-months period following the first subsequent screening. Compared to the 2-year incidence of 349.4/100,000 before the start of the MSP, this amounted to a relative reduction of 16.5 and 21.3%, respectively, in the incidence of ABC among regular MSP participants. CONCLUSIONS: The design employed in this study avoids some of the substantial methodological limitations that compromised previous observational studies. Nevertheless, specific limitations prevail that demand a cautious interpretation of the results. Therefore, the study findings, indicating a reduction in ABC for regular MSP participants, need to be followed with respect to potential impacts on breast cancer mortality rates.

Trends in surgical treatment for breast cancer in Germany after the implementation of the mammography screening program.

In Germany, the nationwide population-based mammography screening program (MSP) was introduced in 2005 and is full-running since 2010. By 2014, incidence rates for invasive breast cancer were very similar to those of the pre-screening era. Therefore, the ongoing effect of the MSP on breast cancer surgery rates can now be investigated. We analyzed population-based breast-conserving (BCS) and mastectomy (MET) surgery rates (per 100,000) among women aged < 50, 50-69 (eligible for the MSP), and 70+ years among women with in situ and invasive breast cancer during 2005-2015. For invasive breast cancer, both BCS and MET rates slightly increased in the age group < 50 years (38.3 in 2005 vs 42.5 in 2015 and 15.7 vs 18.2, respectively). In contrast, MET rates considerably decreased among women aged 50-69 and 70+ years (92 vs 65.4 and 155.4 vs 122.1, respectively), while BCS rates increased in both age groups (210.6 vs 254.4 and 147.2 vs 187, respectively). For in situ breast cancer, MET rates slightly increased in all age groups. BCS rates slightly increased in women aged < 50, but nearly doubled for women aged 50-69 (26.9 vs 49.1) and markedly increased in the 70+ age group (11.5 vs 16.1). During and after the implementation of MSP, there was a strong shift towards BCS within the screening-eligible age group and for women aged 70+ . Women with invasive breast cancer in these age groups may profit from screening with a decline of MET rates in favor of BCS rates at the expense of higher surgery rates for in situ breast cancer.

Implementation of the German Mammography Screening Program (German MSP) and First Results for Initial Examinations, 2005-2009.

BACKGROUND: The German Mammography Screening Program (German MSP) is population-based and intended for women aged 50-69 years (approximately 10.5 million). The program started in 2005 and was implemented within 5 years. This article describes the implementation, structure, and screening process, and presents the results of initial examinations for the prevalence phase. METHODS: Data were collected annually from invitation centers (invitation, attendance), screening units (performance, outcomes), and cancer registries (incidence). RESULTS: In 2009, 92% of all annually eligible women were invited; 50% of the annually eligible population participated. The total cancer detection rate in the period of 2005-2009 was 8.1/1,000; the corresponding recall rate was 5.9%. 19.6% of detected cancers were ductal carcinoma in situ; 76.7% of invasive cancers were ≤ 20 mm in size, 30.2% were ≤ 10 mm, and 75.3% were node-negative. During the implementation period, incidence increased by 37 and 56% in the old and new federal states, respectively. Incidence rates decreased following the prevalence phase. CONCLUSION: The German MSP was successfully implemented. The results of the prevalence phase meet the target values of the European guidelines. Proper functioning of the program is also verified by its effects on breast cancer incidence. To draw reliable conclusions regarding the long-term effects of the program, results from the routine screening rounds have to be awaited.

Effect of mammography screening on surgical treatment for breast cancer: a nationwide analysis of hospitalization rates in Germany 2005-2009.

The aim of this study was to assess the association between the introduction of the nationwide mammography screening program (MSP) and breast cancer surgery rates in Germany 2005-2009. We used nationwide DRG hospitalization files (2005-2009) and analyzed surgery rates for the treatment of invasive and in situ breast cancer in Germany. We used actual numbers of screened women to model the influence of the introduction of the MSP on surgery rates. During 2005 through 2009, the rate of breast-conserving surgery for invasive and in situ breast cancer increased among all age groups. However, rate increases for invasive and in situ breast surgery were largest among women aged 50-69 years (invasive: rate difference [per 100,000] 95.1, 95 % CI 90.7; 99.5; in situ: rate difference 34.4, 95 % CI 32.6; 36.2). Mastectomy rates generally showed little change over time. Conditional on a 70 % participation in the MSP, our model predicts that the estimated increase of mastectomy rates for invasive and in situ breast cancer among women aged 50-69 years during the introductory phase of the MSP would be 4.2 (95 % CI -0.2; 8.6) and 6.1 per 100,000 (95 % CI 5.0; 7.1), respectively. The introduction of the nationwide MSP shows markedly rising rates of breast conserving surgery for women aged 50-69 years with invasive and in situ breast cancer. This increase is expected as a consequence of the first screening round. The model-based estimate for the increase of mastectomy rates, assuming a 70 % MSP participation, is lower than the reported increases observed in MSP in other countries.