Breast cancer mortality in organised mammography screening in Denmark: comparative study

Effects of organized screening programs on breast cancer screening, incidence, and mortality in Europe

We link data on regional Organized Screening Programs (OSPs) throughout Europe with survey data and population-based cancer registries to estimate effects of OSPs on breast cancer screening (mammography), incidence, and mortality. Identification is from regional variation in the existence and timing of OSPs, and in their age-eligibility criteria. We estimate that OSPs, on average, increase mammography by 25 percentage points, increase breast cancer incidence by 16% five years after the OSPs implementation, and reduce breast cancer mortality by about 10% ten years after.

Clinical characteristics and prognosis of postpartum breast cancer

PURPOSE

Postpartum breast cancer (PPBC) is a not well-established subset of breast cancer, and only few studies address its poorer prognosis. However, previous studies show that PPBC is associated with worse outcome with higher rates of metastasis than in young women's breast cancer (YWBC). We aimed to analyze the clinical characteristics and prognosis of PPBC based on the diagnosis period of PPBC.

METHODS

We retrospectively reviewed 208,780 patients with breast cancer from the Korean Breast Cancer Society registry (KBCSR) database between January 2000 and December 2014. We included premenopausal women aged 20-50 years who underwent breast cancer surgery. The patients were classified by 5-year intervals according to the diagnosis period of breast cancer, from the first birth to the breast cancer diagnosis.

RESULTS

Compared with patients in the other groups, patients diagnosed within postpartum 5 years (PPBC < 5 years) group were younger, had a more advanced stage, had lower estrogen receptor (ER) and progesterone receptor (PR) expression, and had a higher human epidermal growth factor receptor 2 (HER2) positive rate. Further, PPBC < 5 years group had a worse survival rate than the nulliparous and other groups (5-year cumulative survival: PPBC < 5 years group, 89%; nulliparous group, 97.3%; 5 ≤ PPBC < 10 years group, 93%). In the multivariate analysis, the PPBC < 5 years group was associated with a worse survival rate (hazard ratio 1.55, 95% confidence interval [CI] 1.148-2.094, p 0.004) after adjustment for age at diagnosis, breast cancer stage, ER and HER2 status, Ki-67 level, and chemotherapy.

CONCLUSION

Our findings indicated that patients diagnosed with breast cancer within the first 5 years after delivery had aggressive characteristics and a poor survival rate. It is important to elucidate the pathophysiology of PPBC and establish novel therapeutic strategies to improve the survival rate.

Interpreting Breast Cancer Mortality Trends Related to Introduction of Mammography Screening: A Simulation Study

Background. Several studies have evaluated the effect of mammography screening on breast cancer mortality based on overall breast cancer mortality trends, with varied conclusions. The statistical power of such trend analyses is, however, not carefully studied. Methods. We estimated how the effect of screening on overall breast cancer mortality is likely to unfold. Because a screening effect is based on earlier treatment, screening can affect only new incident cases after screening introduction. To evaluate the likelihood of detecting screening effects on overall breast cancer mortality time trends, we calculated the statistical power of joinpoint regression analysis on breast cancer mortality trends around screening introduction using simulations. Results. We found that a very gradual increase in population-level screening effect is expected due to prescreening incident cases. Assuming 25% effectiveness of a biennial screening program in reducing breast cancer mortality among women 50 to 69 y of age, the expected reduction in overall breast cancer mortality was 3% after 2 y and reached a long-term effect of 18% after 20 y. In common settings, the statistical power to detect any screening effects using joinpoint regression analysis is very low (<50%), even in an artificial setting of constant risk of baseline breast cancer mortality over time. Conclusions. Population effects of screening on breast cancer mortality emerge very gradually and are expected to be considerably lower than the effects reported in trials excluding women diagnosed before screening. Studies of overall breast cancer mortality time trends have too low statistical power to reliably detect screening effects in most populations. Implications. Researchers and policy makers evaluating mammography screening should avoid using breast cancer mortality trend analysis that does not separate pre- and postscreening incident cases.

HIGHLIGHTS

Population-level mammography screening effects on breast cancer mortality emerge gradually following screening introduction, resulting in very low statistical power of trend analysis.Researchers and policy makers evaluating mammography screening should avoid relying on population-wide breast cancer mortality trends.Expected mammography screening effects at population level are lower than those from screening trials, as many cases of breast cancer fall outside the screening age range.

Diagnose earlier, live longer? The impact of cervical and breast cancer screening on life span

Cancer has become a leading cause of death and aroused the cancer scare. Breast and cervical cancer are two main health threats for women. In order to reduce mortality through early detection and early treatment, cancer screening has been widely recommended and applied for breast and cervical cancer detection and prevention. However, the benefit of cancer screening has been a controversial issue for the recent decades. The Chinese government has launched a free screening program on breast and cervical cancer for women since 2009. There is lack of strong data and sufficient information, however, to examine the effect of breast and cervical cancer screening. A Difference-in-Difference model estimated by Cox proportional hazard estimation was applied to evaluate the effects of breast and cervical cancer screening using data from Nown County Cancer Registry between the year 2009 and 2013. Based on the case study in a county of central China, this study found that the screening program reduced the risk of death, but found the lion’s share for the benefit has been mainly due to the cervical cancer screening rather breast cancer screening, which may be related to the difference between early detection screening and preventive screening. Our results suggest sufficient funding and better education of related cancer knowledge will be meaningful measures for the prevention and treatment of breast and cervical cancer.

Is mammography screening an effective public health intervention? Evidence from a natural experiment

Population-based breast screening programmes aim to improve clinical outcomes, alleviate health inequalities, and reduce healthcare costs. However, while screening can bring about immediate changes in mode of presentation and stage at diagnosis of breast cancer cases, the benefits and harms of these programmes can only be observed at a population level, and only over a long enough timeframe for the cascade of events triggered by screening to culminate in disease-specific mortality reductions. In this paper we exploit a natural experiment resulting from the phased geographic rollout of a national mammography screening programme to examine the impact of screening on breast cancer outcomes from both a patient cohort and a population perspective. Using data on 33,722 breast cancer cases over the period 1994-2011, we employ a difference-in-differences research design using ten-year follow-up data for cases diagnosed before and after the introduction of the programme in screened and unscreened regions. We conclude that although the programme produced the intended intermediate effects on breast cancer presentation and incidence, these failed to translate into significant decreases in overall population-level mortality, though screening may have helped to reduce socioeconomic disparities in late stage breast cancer incidence.

Systematic Analysis of the Global, Regional and National Burden of Cardiovascular Diseases from 1990 to 2017

Background

Previous studies on the burden of cardiovascular diseases (CVDs) were mainly based on limited data of the study period or area, or did not include detailed risk factor analysis.

Objective

To investigate up-to-date temporal and regional trends and risk factors of mortality and disability-adjusted life years (DALYs) attributed to CVDs by age, sex, and disease throughout the world.

Methods

Data for the disease burden of CVDs in 195 countries and territories from 1990 to 2017, including mortality, DALYs, age-standardized mortality rates, and age-standardized DALY rates, were estimated from the Global Burden of Disease Study 2017. Risk factors attributable to deaths and DALYs for CVDs were also estimated using the comparative risk assessment framework.

Results

The number of deaths from CVDs increased by 48.62%, from 11.94 (95% UI 11.78–12.18) million in 1990 to 17.79 (17.53–18.04) million in 2017. However, the age-standardized mortality rate decreased by an average of − 1.45% (− 1.72% to − 1.18%) annually. After fluctuation in the expected age-standardized mortality rate of CVDs in most of the socio-demographic index (SDI) scale, these rates decrease rapidly for SDI values of 0.7 and higher. In 2017, metabolic risks accounted for 73.48% of deaths and 73.25% of DALYs due to CVDs, behavioral factors accounted for 63.23% of deaths and 66.71% of attributable DALYs.

Conclusion

CVDs remain a major global health burden due to the increment in death numbers and DALYs. Aging and the main risk factors are the main drivers of mortality and health loss. More attention to main risk factors should be paid with supportive health policies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s44197-021-00024-2.

Emerging strategies for treating metastasis

The systemic spread of tumor cells is the ultimate cause of the majority of deaths from cancer, yet few successful therapeutic strategies have emerged to specifically target metastasis. Here we discuss recent advances in our understanding of tumor-intrinsic pathways driving metastatic colonization and therapeutic resistance, as well as immune activating strategies to target metastatic disease. We focus on therapeutically exploitable mechanisms, promising strategies in preclinical and clinical development, and emerging areas with potential to become innovative treatments.

Mammograms and Mortality: How Has the Evidence Evolved?

Decades of evidence reveal a complicated relationship between mammograms and mortality. Mammograms may detect deadly cancers early, but they may also lead to the diagnosis and potentially fatal treatment of cancers that would never progress to cause symptoms. I provide a brief history of the evidence on mammograms and mortality, focusing on evidence from clinical trials, and I discuss how this evidence informs mammography guidelines. I then explore the evolution of all-cause mortality relative to breast cancer mortality within an influential clinical trial. I conclude with some responses to the evolving evidence.

Breast cancer mortality and overdiagnosis after implementation of population-based screening in Denmark

Introduction

Service breast cancer screening is difficult to evaluate because there is no unscreened control group. Due to a natural experiment, where 20% of women were offered screening in two regions up to 17 years before other women, Denmark is in a unique position. We utilized this opportunity to assess outcome of service screening.

Materials and methods

Screening was offered in Copenhagen from 1991 and Funen from 1993 to women aged 50–69 years. We used difference-in-differences methodology with a study group offered screening; a historical control group; a regional control group; and a regional–historical control group, comparing breast cancer mortality and incidence, including ductal carcinoma in situ, between study and historical control group adjusted for changes in other regions, and calculating ratios of rate ratios (RRR) with 95% confidence intervals (CI). Data came from Central Population Register; mammography screening databases; Cause of Death Register; and Danish Cancer Register.

Results

For breast cancer mortality, the study group accumulated 1,551,465 person-years and 911 deaths. Long-term breast cancer mortality in Copenhagen was 20% below expected in absence of screening; RRR 0.80 (95% CI 0.71–0.90), and in Funen 22% below; RRR 0.78 (95% CI 0.68–0.89). Combined, cumulative breast cancer incidence in women followed 8+ years post-screening was 2.3% above expected in absence of screening; RRR 1.023 (95% CI 0.97–1.08).

Discussion

Benefit-to-harm ratio of the two Danish screening programs was 2.6 saved breast cancer deaths per overdiagnosed case. Screening can affect only breast cancers diagnosed in screening age. Due to high breast cancer incidence after age 70, only one-third of breast cancer deaths after age 50 could potentially be affected by screening. Increasing upper age limit could be considered, but might affect benefit-to-harm ratio negatively.

Quality-of-life effects of screening mammography in Norway

Mammography screening may save women from dying of breast cancer, although it has not been shown to reduce all-cause mortality. Screening also leads to overdiagnosis and many false positive mammograms aggravating women's quality-of-life. Quality adjusted life years (QALY) analyses of mammography screening have so far, calculated life years gained assuming that all prevented breast cancer deaths translate into a reduction in all-cause mortality. We calculated net QALYs in two hypothesized cohorts of 100,000 Norwegian women; one screened biennially from age 50 to 69 years and one not screened. We followed both cohorts to age 85 years. We used EQ-5D and an alternative equity weighted QALY instrument to estimate utility losses. In the screening cohort, we assumed 20% false positive tests during screening, different levels of overdiagnosis (20-75%) and different levels of breast cancer mortality reduction (10-30%). We assumed that reductions in breast cancer mortality only to a limited extent (20, 50 or 80%), resulted in reductions in all-cause mortality. We calculated both undiscounted and discounted (4%) QALYs. Assuming that 50% of the reduction in breast cancer mortality translated to a reduction in all-cause mortality and using estimated levels of benefits and harms in modern screening programs (50-75% overdiagnosis and 10% reduction in breast cancer mortality), undiscounted equity weighted QALY loss varied from 437 to 875 per 100,000 women. Using the levels of benefit and harms as reported in 30-40 years old randomized trials (30% overdiagnosis and 15% reduction in breast cancer mortality), undiscounted equity weighted QALY gain was 535 per 100,000. Net QALY in modern mammography screening in Norway is negative. Results could also be representative for Sweden, Denmark, UK and the US.

Factors associated with readmissions in women participating in screening programs and treated for breast cancer: a retrospective cohort study

Background

We aimed to identify the risk factors associated with early, late and long-term readmissions in women diagnosed with breast cancer participating in screening programs.

Methods

We performed a multicenter cohort study of 1055 women aged 50–69 years participating in Spanish screening programs, diagnosed with breast cancer between 2000 and 2009, and followed up to 2014. Readmission was defined as a hospital admission related to the disease and/or treatment complications, and was classified as early (< 30 days), late (30 days-1 year), or long-term readmission (> 1 year). We used logistic regression to estimate the adjusted odds ratios (aOR), and 95% confidence intervals (95% CI) to explore the factors associated with early, late and long-term readmissions, adjusting by women’s and tumor characteristics, detection mode, treatments received, and surgical and medical complications.

Results

Among the women included, early readmission occurred in 76 (7.2%), late readmission in 87 (8.2%), long-term readmission in 71 (6.7%), and no readmission in 821 (77.8%). Surgical complications were associated with an increased risk of early readmissions (aOR = 3.62; 95%CI: 1.27–10.29), and medical complications with late readmissions (aOR = 8.72; 95%CI: 2.83–26.86) and long-term readmissions (aOR = 4.79; 95%CI: 1.41–16.31).

Conclusion

Our results suggest that the presence of surgical or medical complications increases readmission risk, taking into account the detection mode and treatments received. Identifying early complications related to an increased risk of readmission could be useful to adapt the management of patients and reduce further readmissions.

Trial Registration

ClinicalTrials.govIdentifier: NCT03165006. Registration date: May 22, 2017 (Retrospectively registered).

Effect of screening mammography on breast cancer mortality: Quasi-experimental evidence from rollout of the Dutch population-based program with 17-year follow-up of a cohort

There is uncertainty about the magnitude of the effect of screening mammography on breast cancer mortality. The relevance and validity of evidence from dated randomized controlled trials has been questioned, whereas observational studies often lack a valid comparison group. There is no estimate of the effect of one screening invitation only. We exploited the geographic rollout of the Dutch screening mammography program across municipalities to estimate the effects of one additional biennial screening invitation on breast cancer and all‐cause mortality. Population administrative data provided vital status and cause of death of a cohort of women aged 49–63 in 1995 over 17 years. Linear probability models were used to estimate the mortality effects. We estimated 154 fewer breast cancer deaths (95% confidence interval: 40–267; p = 0.01) over 17 years in a population of 100,000 women aged 49–63 who received one additional biennial screening invitation, which corresponds to an 9.6% risk reduction for a woman of age 56. The estimated effect on all‐cause mortality was negative but not close to statistical significance. Our study shows that one single invitation for breast cancer screening is effective in reducing breast cancer mortality, which is important for health policy. The effect is smaller than previous estimates of the effect of invitation for multiple screens, which further emphasizes the importance of achieving regular participation.

What's new?

To date, there is still uncertainty about the magnitude of the effect of screening mammography on breast cancer mortality. Here, the authors exploited the geographic rollout of the Dutch screening mammography program and high‐quality national population, cancer, and death registries to avoid limitations of observational research by comparing breast cancer mortality across groups of women of the same age who joined the mammography program at different dates. The analysis provides a unique estimate of the effect of one additional invitation for screening mammography on breast cancer mortality (around 10%) and delivers evidence in favour of the effectiveness of such screening.

Utilisation of mammography by women with mobility impairment in the UK: secondary analysis of cross-sectional data

OBJECTIVES

Research has shown that people with physical impairment report lower utilisation of preventive services. The aim of this study was to examine whether women with mobility impairments have lower odds of using mammography compared with women with no such impairment, and explore the factors that are associated with lower utilisation.

SAMPLE AND DESIGN

We performed secondary analysis, using logistic regressions, of deidentified cross-sectional data from the European Health Interview Survey, Wave 2. The sample included 9491 women from across the UK, 2697 of whom had mobility impairment. The survey method involved face-to-face and telephone interviews.

OUTCOME MEASURES

Self-report of the last time a mammogram was undertaken.

RESULTS

Adjusting for various demographic and socioeconomic variables, women with mobility impairment had 1.3 times (95% CI 0.70 to 0.92) lower odds of having a mammogram than women without mobility impairment. Concerning women with mobility impairment, married women had more than twice the odds of having a mammogram than women that had never been married (OR 2.07, 95% CI 1.49 to 2.88). Women in Scotland had 1.5 times (95% CI 1.08 to 2.10) higher odds of undertaking the test than women in England. Women with upper secondary education had 1.4 times (95% CI 1.10 to 1.67) higher odds of undergoing the test than women with primary or lower secondary education. Also, women from higher quintiles (third and fifth quintiles) had higher odds of using mammography, with the women in the fifth quintile having 1.5 times (95% CI 1.02 to 2.15) higher odds than women from the first quintile.

CONCLUSIONS

In order to achieve equitable access to mammography for all women, it is important to acknowledge the barriers that impede women with mobility impairment from using the service. These barriers can refer to structural disadvantage, such as lower income and employment rate, transportation barriers, or previous negative experiences, among others.

Variability of breast surgery in women participating in breast cancer screening programs

INTRODUCTION

Currently, variability in surgical practice is a problem to be solved. The aim of this study is to describe the variability in the surgical treatment of breast cancer and to analyze the factors associated with it.

METHODS

The study population included 1057 women diagnosed with breast cancer and surgically treated. Our data were from the CaMISS retrospective cohort.

RESULTS

The mean age at diagnosis was 59.3 ± 5 years. A total of 732 patients were diagnosed through screening mammograms and 325 patients as interval cancers. The mastectomy surgery was more frequent in the tumors detected between intervals (OR=2.5; [95%CI: 1.8-3.4]), although this effect disappeared when we adjusted for the rest of the variables. The most important factor associated with performing a mastectomy was TNM: tumors in stage III-IV had an OR of 7.4 [95%CI: 3.9-13.8], increasing in adjusted OR to 21.7 [95%CI: 11.4-41.8]. Histologically, infiltrating lobular carcinoma maintains significance in adjusted OR (OR=2.5; [95%CI: 1.4-4.7]). According to the screening program, there were significant differences in surgical treatment. Program 3 presented an OR of non-conservative surgery of 4.0 [95%CI: 1.8-8.9]. This program coincided with the highest percentage of reconstruction (58.3%).

CONCLUSIONS

This study shows that, despite taking into account patient and tumor characteristics, there is great variability in the type of surgery depending on the place of diagnosis.

Outcome of breast cancer screening in Denmark

BACKGROUND

In Denmark, national roll-out of a population-based, screening mammography program took place in 2007-2010. We report on outcome of the first four biennial invitation rounds.

METHODS

Data on screening outcome were retrieved from the 2015 and 2016 national screening quality reports. We calculated coverage by examination; participation after invitation; detection-, interval cancer- and false-positive rates; cancer characteristics; sensitivity and specificity, for Denmark and for the five regions.

RESULTS

At the national level coverage by examination remained at 75-77%; lower in the Capital Region than in the rest of Denmrk. Detection rate was slightly below 1% at first screen, 0.6% at subsequent screens, and one region had some fluctuation over time. Ductal carcinoma in situ (DCIS) constituted 13-14% of screen-detected cancers. In subsequent rounds, 80% of screen-detected invasive cancers were node negative and 40% ≤10 mm. False-positive rate was around 2%; higher for North Denmark Region than for the rest of Denmark. Three out of 10 breast cancers in screened women were diagnosed as interval cancers.

CONCLUSIONS

High coverage by examination and low interval cancer rate are required for screening to decrease breast cancer mortality. Two pioneer local screening programs starting in the 1990s were followed by a decrease in breast cancer mortality of 22-25%. Coverage by examination and interval cancer rate of the national program were on the favorable side of values from the pioneer programs. It appears that the implementation of a national screening program in Denmark has been successful, though regional variations need further evaluation to assure optimization of the program.

Mammography screening: A major issue in medicine

Breast cancer mortality is declining in most high-income countries. The role of mammography screening in these declines is much debated. Screening impacts cancer mortality through decreasing the incidence of number of advanced cancers with poor prognosis, while therapies and patient management impact cancer mortality through decreasing the fatality of cancers. The effectiveness of cancer screening is the ability of a screening method to curb the incidence of advanced cancers in populations. Methods for evaluating cancer screening effectiveness are based on the monitoring of age-adjusted incidence rates of advanced cancers that should decrease after the introduction of screening. Likewise, cancer-specific mortality rates should decline more rapidly in areas with screening than in areas without or with lower levels of screening but where patient management is similar. These two criteria have provided evidence that screening for colorectal and cervical cancer contributes to decreasing the mortality associated with these two cancers. In contrast, screening for neuroblastoma in children was discontinued in the early 2000s because these two criteria were not met. In addition, overdiagnosis - i.e. the detection of non-progressing occult neuroblastoma that would not have been life-threatening during the subject's lifetime - is a major undesirable consequence of screening. Accumulating epidemiological data show that in populations where mammography screening has been widespread for a long time, there has been no or only a modest decline in the incidence of advanced cancers, including that of de novo metastatic (stage IV) cancers at diagnosis. Moreover, breast cancer mortality reductions are similar in areas with early introduction and high penetration of screening and in areas with late introduction and low penetration of screening. Overdiagnosis is commonplace, representing 20% or more of all breast cancers among women invited to screening and 30-50% of screen-detected cancers. Overdiagnosis leads to overtreatment and inflicts considerable physical, psychological and economic harm on many women. Overdiagnosis has also exerted considerable disruptive effects on the interpretation of clinical outcomes expressed in percentages (instead of rates) or as overall survival (instead of mortality rates or stage-specific survival). Rates of radical mastectomies have not decreased following the introduction of screening and keep rising in some countries (e.g. the United States of America (USA)). Hence, the epidemiological picture of mammography screening closely resembles that of screening for neuroblastoma. Reappraisals of Swedish mammography trials demonstrate that the design and statistical analysis of these trials were different from those of all trials on screening for cancers other than breast cancer. We found compelling indications that these trials overestimated reductions in breast cancer mortality associated with screening, in part because of the statistical analyses themselves, in part because of improved therapies and underreporting of breast cancer as the underlying cause of death in screening groups. In this regard, Swedish trials should publish the stage-specific breast cancer mortality rates for the screening and control groups separately. Results of the Greater New York Health Insurance Plan trial are biased because of the underreporting of breast cancer cases and deaths that occurred in women who did not participate in screening. After 17 years of follow-up, the United Kingdom (UK) Age Trial showed no benefit from mammography screening starting at age 39-41. Until around 2005, most proponents of breast screening backed the monitoring of changes in advanced cancer incidence and comparative studies on breast cancer mortality for the evaluation of breast screening effectiveness. However, in an attempt to mitigate the contradictions between results of mammography trials and population data, breast-screening proponents have elected to change the criteria for the evaluation of cancer screening effectiveness, giving precedence to incidence-based mortality (IBM) and case-control studies. But practically all IBM studies on mammography screening have a strong ecological component in their design. The two IBM studies done in Norway that meet all methodological requirements do not document significant reductions in breast cancer mortality associated with mammography screening. Because of their propensity to exaggerate the health benefits of screening, case-control studies may demonstrate that mammography screening could reduce the risk of death from diseases other than breast cancer. Numerous statistical model approaches have been conducted for estimating the contributions of screening and of patient management to reductions in breast cancer mortality. Unverified assumptions are needed for running these models. For instance, many models assume that if screening had not occurred, the majority of screen-detected asymptomatic cancers would have progressed to symptomatic advanced cancers. This assumption is not grounded in evidence because a large proportion of screen-detected breast cancers represent overdiagnosis and hence non-progressing tumours. The accumulation of population data in well-screened populations diminishes the relevance of model approaches. The comparison of the performance of different screening modalities - e.g. mammography, digital mammography, ultrasonography, magnetic resonance imaging (MRI), three-dimensional tomosynthesis (TDT) - concentrates on detection rates, which is the ability of a technique to detect more cancers than other techniques. However, a greater detection rate tells little about the capacity to prevent interval and advanced cancers and could just reflect additional overdiagnosis. Studies based on the incidence of advanced cancers and on the evaluation of overdiagnosis should be conducted before marketing new breast-imaging technologies. Women at high risk of breast cancer (i.e. 30% lifetime risk and more), such as women with BRCA1/2 mutations, require a close breast surveillance. MRI is the preferred imaging method until more radical risk-reduction options are eventually adopted. For women with an intermediate risk of breast cancer (i.e. 10-29% lifetime risk), including women with extremely dense breast at mammography, there is no evidence that more frequent mammography screening or screening with other modalities actually reduces the risk of breast cancer death. A plethora of epidemiological data shows that, since 1985, progress in the management of breast cancer patients has led to marked reductions in stage-specific breast cancer mortality, even for patients with disseminated disease (i.e. stage IV cancer) at diagnosis. In contrast, the epidemiological data point to a marginal contribution of mammography screening in the decline in breast cancer mortality. Moreover, the more effective the treatments, the less favourable are the harm-benefit balance of screening mammography. New, effective methods for breast screening are needed, as well as research on risk-based screening strategies.

Mammographic Screening at Age 40 or 45? What Difference Does it Make? the Potential Impact of American Cancer Society Mammography Screening Guidelines

This is a 10-year retrospective chart review evaluating the potential impact of the most recent American Cancer Society mammography screening guidelines which excludes female patients aged 40 to 44 years from routine annual screening mammography. Instead they recommend screening mammography starting at age 45 with the option to begin screening earlier if the patient desires. The institutional cancer registry was systematically searched to identify all women aged 40 to 44 years treated for breast cancer over a 10-year period. These women were separated into two cohorts: screening mammography detected cancer (SMDC) and nonscreening mammography detected cancer (NSMDC). Statistical analysis of the cohorts was performed for lymph node status (SLN), five-year disease-free survival, and five-year overall survival. Women with SMDC had a significantly lower incidence of SLN positive cancer than the NSMDC group, 9 of 63 (14.3%) versus 36 of 81 (44 %; P < 0.001). The five-year disease-free survival for both groups was 84 per cent for SMDC and 80 per cent for NSMDC; this was not statistically significant. The five-year overall survival was statistically significant at 94 per cent for the SMDC group and 80 per cent for the NSMDC group (P < 0.05). This review demonstrates the significance of mammographic screening for early detection and treatment of breast cancer. Mammographic screening in women aged 40 to 44 detected tumors with fewer nodal metastases, resulting in improved survival and reaffirming the need for annual mammographic screening in this age group.

The Breast Cancer Screening "Arcade" and the "Whack-A-Mole" Efforts to Reduce Access to Screening

The effort to reduce access to breast cancer screening has been going on for decades. As each piece of misinformation has been published, scientific responses have exposed the fallacies, but then new "alternative facts" are generated. The effort has been compared to the arcade game "Whack-a-Mole" in which one false argument is addressed only to have a new one "pop up" to replace it. This has ranged from the false claim that early detection would have no effect on breast cancer, to the fallacious idea that early detection was leading to early deaths among young women, to the more recent false suggestion that tens of thousands of breast cancers found by mammography would disappear if left undetected. The following is a short review of a number of nonscientifically derived "Moles" that have been "Whacked" by science.

Overdiagnosis in breast cancer screening: The impact of study design and calculations

Overdiagnosis in breast cancer screening is an important issue. A recent study from Denmark concluded that one in three breast cancers diagnosed in screening areas in women aged 50-69 years were overdiagnosed. The purpose of this short communication was to disentangle the study's methodology in order to evaluate the soundness of this conclusion. We found that both the use of absolute differences as opposed to ratios; the sole focus on non-advanced tumours and the crude allocation of tumours and person-years by screening history for women aged 70-84 years, all contributed to the very high estimate of overdiagnosis. Screening affects cohorts of screened women. Danish registers allow very accurate mapping of the fate of every woman. We should be past the phase where studies of overdiagnosis are based on the fixed age groups from routine statistics.

Benefit-to-harm ratio of the Danish breast cancer screening programme

The primary aim of breast cancer screening is to reduce breast cancer mortality, but screening also has negative side‐effects as overdiagnosis. To evaluate a screening programme, both benefits and harms should be considered. Published estimates of the benefit‐to‐harm ratio, the number of breast cancer deaths prevented divided by the number of overdiagnosed breast cancer cases, varied considerably. The objective of the study was to estimate the benefit‐to‐harm ratio of breast cancer screening in Denmark. The numbers of breast cancer deaths prevented and overdiagnosed cases [invasive and ductal carcinoma in situ (DCIS)] were estimated per 1,000 women aged 50–79, using national published estimates for breast cancer mortality and overdiagnosis, and national incidence and mortality rates. Estimations were made for both invited and screened women. Among 1,000 women invited to screening from age 50 to age 69 and followed until age 79, we estimated that 5.4 breast cancer deaths would be prevented and 2.1 cases overdiagnosed, under the observed scenario in Denmark of a breast cancer mortality reduction of 23.4% and 2.3% of the breast cancer cases being overdiagnosed. The estimated benefit‐to‐harm ratio was 2.6 for invited women and 2.5 for screened women. Hence, 2–3 women would be prevented from dying from breast cancer for every woman overdiagnosed with invasive breast cancer or DCIS. The difference between the previous published ratios and 2.6 for Denmark is probably more a reflection of the accuracy of the underlying estimates than of the actual screening programmes. Therefore, benefit‐to‐harm ratios should be used cautiously.

What's new?

Breast cancer screening reduces breast cancer mortality, but one negative side‐effect is overdiagnosis. Published estimates of the benefit‐to‐harm ratio–the number of prevented breast cancer deaths divided by the number of overdiagnosed breast cancer cases–vary considerably. This study reports a benefit‐to‐harm ratio of 2.6 for women invited to breast cancer screening in Denmark. Among 1,000 invited women from age 50 and followed up until 79, 2–3 women would be prevented from dying from breast cancer for every overdiagnosed woman. International variations in benefit‐to‐harm ratios probably reflect differences in the accuracy of underlying estimates more than differences between screening programmes.

Breast Cancer Screening Programmes across the WHO European Region: Differences among Countries Based on National Income Level

Breast cancer (BC) is the most frequent tumour affecting women all over the world. In low- and middle-income countries, where its incidence is expected to rise further, BC seems set to become a public health emergency. The aim of the present study is to provide a systematic review of current BC screening programmes in WHO European Region to identify possible patterns. Multiple correspondence analysis was performed to evaluate the association among: measures of occurrence; GNI level; type of BC screening programme; organization of public information and awareness campaigns regarding primary prevention of modifiable risk factors; type of BC screening services; year of screening institution; screening coverage and data quality. A key difference between High Income (HI) and Low and Middle Income (LMI) States, emerging from the present data, is that in the former screening programmes are well organized, with approved screening centres, the presence of mobile units to increase coverage, the offer of screening tests free of charge; the fairly high quality of occurrence data based on high-quality sources, and the adoption of accurate methods to estimate incidence and mortality. In conclusion, the governments of LMI countries should allocate sufficient resources to increase screening participation and they should improve the accuracy of incidence and mortality rates.

The impact of the Polish mass breast cancer screening program on prognosis in the Pomeranian Province

INTRODUCTION

Mammographic screening results in diagnosis of less advanced breast cancer (BC). A meta-analysis of randomized clinical trials confirmed that BC screening reduces mortality. In 2007, the National Breast Cancer Screening Program (NBCSP) was established in Poland with the crucial aim of reducing mortality from BC. The purpose of this study was to assess the impact of participation in the NBCSP on prognosis.

MATERIAL AND METHODS

A single institution, non-randomized retrospective study was undertaken. The study population comprised 643 patients with BC treated in the Department of Surgical Oncology (DSO) at the Medical University of Gdansk over a 4-year period, from 01.01.2007 until 31.12.2010. Patients were divided into two groups: group A - patients who participated in the NBCSP (n = 238, 37.0%); and group B - patients who did not participate in the NBCSP (n = 405, 63.0%).

RESULTS

Statistical analysis revealed that group A displayed a less advanced AJCC stage (more patients in AJCC stage I, p = 0.002), lower tumor diameter (more patients with pT1, p = 0.006, and pT < 15 mm, p = 0.008) and a lower incidence of metastases to axillary lymph nodes (more patients with pNO, p = 0.01). From 2009 to 2010 the NBCSP revealed a statistically significant benefit - significantly more patients in stage 0 + I (60.7% vs. 48.8%, p = 0.018) and with tumors pT < 15 mm (48.8% vs. 35.1%, p = 0.011) were observed in group A.

CONCLUSIONS

The study results revealed the beneficial impact of the NBCSP. Superior prognostic factors and favorable staging were observed in women who participated in the NBCSP.

[Why reconsider the recommendation of breast cancer screening?]

The aim of this article was to discuss the recommendation of mammogram screening for breast cancer and its technical basis. The first part discusses criteria for the decision, which should be consistent with high-quality scientific evidence. The second part discusses over-diagnosis (the greatest harm of screening) and its meaning in questioning the natural history of disease model. The third part summarizes studies on the efficacy, effectiveness, and harms of screening, showing that the latter (especially over-diagnosis and false-positives) are significant, shedding doubt on the balance between harms and benefits. In conclusion, the recommendation of mammogram screening at any age should be reconsidered by Brazilian health authorities.

Factors predictive of mortality in a cohort of women surgically treated for breast cancer from 1997 to 2014

OBJECTIVE

To determine whether previously reported factors predictive of breast cancer mortality are effectively linked with mortality, particularly breast-cancer-specific mortality.

METHODS

In a prospective study, clinical, surgical, and follow-up data were assessed for consecutive patients with breast cancer who underwent surgery between 1997 and 2014 at two centers in Barcelona, Spain. Predictors of mortality were assessed by multivariate analysis.

RESULTS

Overall, 2134 patients were treated for 2206 breast tumors. Overall mortality was 15.0% (n=319), and breast-cancer-specific mortality was 9.0% (n=191). On multivariate analysis, the most significant factors associated with breast-cancer-specific mortality were clinical stage, inmunohistochemical profile, locoregional relapse, and lymphovascular invasion (all P<0.001). Age at onset, participation in the mass-screening program, histologic grade, and multicentricity were not significant. Patients with three or more positive axillary nodes sustained a specific mortality significantly higher than did node-negative patients or those with fewer than three positive nodes.

CONCLUSION

Factors predictive of breast cancer mortality were clinical stage, locoregional relapse, molecular classification, lymphovascular invasion, and neoadjuvant chemotherapy. As a single factor, nodal disease becomes relevant only when three or more lymph nodes are involved.

Observed and Predicted Risk of Breast Cancer Death in Randomized Trials on Breast Cancer Screening

BACKGROUND

The role of breast screening in breast cancer mortality declines is debated. Screening impacts cancer mortality through decreasing the number of advanced cancers with poor diagnosis, while cancer treatment works through decreasing the case-fatality rate. Hence, reductions in cancer death rates thanks to screening should directly reflect reductions in advanced cancer rates. We verified whether in breast screening trials, the observed reductions in the risk of breast cancer death could be predicted from reductions of advanced breast cancer rates.

PATIENTS AND METHODS

The Greater New York Health Insurance Plan trial (HIP) is the only breast screening trial that reported stage-specific cancer fatality for the screening and for the control group separately. The Swedish Two-County trial (TCT)) reported size-specific fatalities for cancer patients in both screening and control groups. We computed predicted numbers of breast cancer deaths, from which we calculated predicted relative risks (RR) and (95% confidence intervals). The Age trial in England performed its own calculations of predicted relative risk.

RESULTS

The observed and predicted RR of breast cancer death were 0.72 (0.56-0.94) and 0.98 (0.77-1.24) in the HIP trial, and 0.79 (0.78-1.01) and 0.90 (0.80-1.01) in the Age trial. In the TCT, the observed RR was 0.73 (0.62-0.87), while the predicted RR was 0.89 (0.75-1.05) if overdiagnosis was assumed to be negligible and 0.83 (0.70-0.97) if extra cancers were excluded.

CONCLUSIONS

In breast screening trials, factors other than screening have contributed to reductions in the risk of breast cancer death most probably by reducing the fatality of advanced cancers in screening groups. These factors were the better management of breast cancer patients and the underreporting of breast cancer as the underlying cause of death. Breast screening trials should publish stage-specific fatalities observed in each group.

Non-attendance of mammographic screening: the roles of age and municipality in a population-based Swedish sample

Background

Inequality in health and health care is increasing in Sweden. Contributing to widening gaps are various factors that can be assessed by determinants, such as age, educational level, occupation, living area and country of birth. A health care service that can be used as an indicator of health inequality in Sweden is mammographic screening. The non-attendance rate is between 13 and 31 %, while the average is about 20 %. This study aims to shed light on three associations: between municipality and non-attendance, between age and non-attendance, and the interaction of municipality of residence and age in relation to non-attendance.

Methods

The study is based on data from the register that identifies attenders and non-attenders of mammographic screening in a Swedish county, namely the Radiological Information System (RIS). Further, in order to provide a socio-demographic profile of the county’s municipalities, aggregated data for women in the age range 40–74 in 2012 were retrieved from Statistics Sweden (SCB), the Public Health Agency of Sweden, the National Board of Health and Welfare, and the Swedish Social Insurance Agency. The sample consisted of 52,541 women. Analysis conducted of the individual data were multivariate logistic regressions, and pairwise chi-square tests.

Results

The results show that age and municipality of residence associated with non-attendance of mammographic screening. Municipality of residence has a greater impact on non-attendance among women in the age group 70 to 74. For most of the age categories there were differences between the municipalities in regard to non-attendance to mammographic screening.

Conclusions

Age and municipality of residence affect attendance of mammographic screening. Since there is one sole and pre-selected mammographic screening facility in the county, distance to the screening facility may serve as one explanation to non-attendance which is a determinant of inequity. From an equity perspective, lack of equal access to health and health care influences facility utilization.

International Variation in Female Breast Cancer Incidence and Mortality Rates

BACKGROUND

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer-related death among women worldwide. Herein, we examine global trends in female breast cancer rates using the most up-to-date data available.

METHODS

Breast cancer incidence and mortality estimates were obtained from GLOBOCAN 2012 (globocan.iarc.fr). We analyzed trends from 1993 onward using incidence data from 39 countries from the International Agency for Research on Cancer and mortality data from 57 countries from the World Health Organization.

RESULTS

Of 32 countries with incidence and mortality data, rates in the recent period diverged-with incidence increasing and mortality decreasing-in nine countries mainly in Northern/Western Europe. Both incidence and mortality decreased in France, Israel, Italy, Norway, and Spain. In contrast, incidence and death rates both increased in Colombia, Ecuador, and Japan. Death rates also increased in Brazil, Egypt, Guatemala, Kuwait, Mauritius, Mexico, and Moldova.

CONCLUSIONS

Breast cancer mortality rates are decreasing in most high-income countries, despite increasing or stable incidence rates. In contrast and of concern are the increasing incidence and mortality rates in a number of countries, particularly those undergoing rapid changes in human development. Wide variations in breast cancer rates and trends reflect differences in patterns of risk factors and access to and availability of early detection and timely treatment.

IMPACT

Increased awareness about breast cancer and the benefits of early detection and improved access to treatment must be prioritized to successfully implement breast cancer control programs, particularly in transitioning countries.

Improvements in US Breast Cancer Survival and Proportion Explained by Tumor Size and Estrogen-Receptor Status

PURPOSE

Breast cancer mortality began declining in many Western countries during the late 1980s. We estimated the proportion of improvements in stage- and age-specific breast cancer survival in the United States explained by tumor size or estrogen receptor (ER) status.

METHODS

We estimated hazard ratios for breast cancer-specific death from time of invasive breast cancer diagnosis in the National Cancer Institute's Surveillance, Epidemiology, and End Results 9 Registries Database from 1973 to 2010, with and without stratification by tumor size and ER status.

RESULTS

Hazards from breast cancer-specific death declined from 1973 to 2010, not only in the first 5 years after diagnosis, but also thereafter. Stratification by tumor size explained less than 17% of the improvements comparing 2005 to 2010 versus 1973 to 1979, except for women age ≥ 70 years with local (49%) or regional (38%) disease. Tumor size usually accounted for more of the improvement in the first 5 years after diagnosis than later. Additional adjustment for ER status (positive, negative, or unknown) from 1990 to 2010 did not explain much more of the improvement, except for women age ≥ 70 years within 5 years after diagnosis.

CONCLUSION

Most stage-specific survival improvement in women younger than age 70 years old is unexplained by tumor size and ER status, suggesting a key role for treatment. In the first 5 years after diagnosis, tumor size contributed importantly for women ≥ 70 years old with local and regional stage, and stratification by tumor size and ER status explained even more of the survival improvement among women age ≥ 70 years.

Viewpoint: It is time to reconsider policy for population-based mammography screening

Breast cancer in women is an important cause of morbidity and mortality. Many countries in the Western world have widely promoted early detection through mammography screening and established population-based screening programs. Over the past 15 years, there has been growing debate about the benefits and harms of universal mammography screening. This article presents findings from the latest systematic review conducted by the Cochrane Collaboration and from the Canadian National Breast Screening Study 25-year follow up. The authors of both reports conclude there is no reliable evidence that population-based mammography screening reduces mortality, but there is good evidence of harm in the form of false positive findings, over-diagnosis and unnecessary treatment, and associated psychological distress. It is time for policymakers to discontinue universal population-based mammography screening and shift to a more selective approach to early detection.

Prevenção quaternária: as bases para sua operacionalização na relação médico-paciente

O objetivo deste artigo é apresentar as bases clínicas e conceituais para se operacionalizar a prevenção quaternária na prática dos serviços de Atenção Primária à Saúde e no ambiente de ensino e/ou programa de residência em medicina de família. Utilizou-se o modelo aprimorado de Calgary-Cambridge como substrato organizativo da consulta médica, de modo a inserir a prevenção quaternária em dois momentos: diagnóstico e plano de cuidados. Para fortalecer a prevenção quaternária nesses dois momentos da consulta discute-se: a) os eixos conceituais das doenças (anatomopatológico, fisiopatológico, semiológico e epidemiológico); b) as abordagens explicativas do fenômeno do adoecimento (ontológica e dinâmica); e c) o sofrimento em relação ao tempo (presente e futuro), diferenciando o sofrimento vivenciado no presente das preocupações com a saúde futura. Conclui-se que apesar das limitações da proposta, a formalização da prevenção quaternária no processo de consulta pode auxiliar a reduzir o automatismo diagnóstico e prescritivo que muito tem medicalizado as expressões do adoecer no cotidiano dos serviços da atenção primária à saúde.

Beyond the mammography debate: a moderate perspective

After some decades of contention, one can almost despair and conclude that (paraphrasing) "the mammography debate you will have with you always." Against that sentiment, in this review I argue, after reflecting on some of the major themes of this long-standing debate, that we must begin to move beyond the narrow borders of claim and counterclaim to seek consensus on what the balance of methodologically sound and critically appraised evidence demonstrates, and also to find overlooked underlying convergences; after acknowledging the reality of some residual and non-trivial harms from mammography, to promote effective strategies for harm mitigation; and to encourage deployment of new screening modalities that will render many of the issues and concerns in the debate obsolete. To these ends, I provide a sketch of what this looking forward and beyond the current debate might look like, leveraging advantages from abbreviated breast magnetic resonance imaging technologies (such as the ultrafast and twist protocols) and from digital breast tomosynthesis-also known as three-dimensional mammography. I also locate the debate within the broader context of mammography in the real world as it plays out not for the disputants, but for the stakeholders themselves: the screening-eligible patients and the physicians in the front lines who are charged with enabling both the acts of screening and the facts of screening at their maximally objective and patient-accessible levels to facilitate informed decisions.

Determinants of mammography screening participation among Turkish immigrant women in Germany--a qualitative study reflecting key informants' and women's perspectives

Mammography screening programmes aiming to reduce mortality from breast cancer are implemented in most European countries. Immigrant women are less likely to participate than women of the respective autochthonous populations in several European countries but not in Germany. Qualitative, semi-structured interviews were conducted with 16 key informants and 10 Turkish immigrant women aged 50-69 years to analyse the factors influencing their screening participation in Germany. Interviews were analysed using summarising content analysis. The Theory of Planned Behaviour was used for structuring the results. Key informants stated poor German language skills and insufficient knowledge about breast cancer and screening as factors influencing screening participation. Immigrant women demonstrated basic knowledge about screening, but their attitudes towards screening varied. Information from the invitation letter of the screening programme was often filtered by family members. Key informants tended to emphasise barriers and system-related factors while the Turkish women focused more on factors on the individual level. Contrasting both perspectives is helpful for health professionals to critically assess their own views. Measures to improve screening participation need to address not only barriers but also take women's attitudes and norms into account, thus helping women to make an informed decision.

Effects of age on the detection and management of breast cancer

Currently, breast cancer affects approximately 12% of women worldwide. While the incidence of breast cancer rises with age, a younger age at diagnosis is linked to increased mortality. We discuss age related factors affecting breast cancer diagnosis, management and treatment, exploring key concepts and identifying critical areas requiring further research. We examine age as a factor in breast cancer diagnosis and treatment relating it to factors such as genetic status, breast cancer subtype, hormone factors and nodal status. We examine the effects of age as seen through the adoption of population wide breast cancer screening programs. Assessing the incidence rates of each breast cancer subtype, in the context of age, we examine the observed correlations. We explore how age affects patient's prognosis, exploring the effects of age on stage and subtype incidence. Finally we discuss the future of breast cancer diagnosis and treatment, examining the potential of emerging tests and technologies (such as microRNA) and how novel research findings are being translated into clinically relevant practices.

Benefits and harms of mammography screening

Mammography screening for breast cancer is widely available in many countries. Initially praised as a universal achievement to improve women's health and to reduce the burden of breast cancer, the benefits and harms of mammography screening have been debated heatedly in the past years. This review discusses the benefits and harms of mammography screening in light of findings from randomized trials and from more recent observational studies performed in the era of modern diagnostics and treatment. The main benefit of mammography screening is reduction of breast-cancer related death. Relative reductions vary from about 15 to 25% in randomized trials to more recent estimates of 13 to 17% in meta-analyses of observational studies. Using UK population data of 2007, for 1,000 women invited to biennial mammography screening for 20 years from age 50, 2 to 3 women are prevented from dying of breast cancer. All-cause mortality is unchanged. Overdiagnosis of breast cancer is the main harm of mammography screening. Based on recent estimates from the United States, the relative amount of overdiagnosis (including ductal carcinoma in situ and invasive cancer) is 31%. This results in 15 women overdiagnosed for every 1,000 women invited to biennial mammography screening for 20 years from age 50. Women should be unpassionately informed about the benefits and harms of mammography screening using absolute effect sizes in a comprehensible fashion. In an era of limited health care resources, screening services need to be scrutinized and compared with each other with regard to effectiveness, cost-effectiveness and harms.

Decline in breast cancer mortality: how much is attributable to screening?

OBJECTIVES

When estimating the decline in breast cancer mortality attributable to screening, the challenge is to provide valid comparison groups and to distinguish the screening effect from other effects. In Funen, Denmark, multidisciplinary breast cancer management teams started before screening was introduced; both activities came later in the rest of Denmark. Because Denmark had national protocols for breast cancer treatment, but hardly any opportunistic screening, Funen formed a "natural experiment", providing valid comparison groups and enabling the separation of the effect of screening from other factors.

METHODS

Using Poisson regression we compared the observed breast cancer mortality rate in Funen after implementation of screening with the expected rate without screening. The latter was estimated from breast cancer mortality in the rest of Denmark controlled for historical differences between Funen/rest of Denmark. As multidisciplinary teams were introduced gradually in the rest of Denmark from 1994, the screening effect was slightly underestimated.

RESULTS

Over 14 years, women targeted by screening in Funen experienced a 22% (95% confidence interval 11%-32%) reduction in breast cancer mortality associated with screening (a reduction in breast cancer mortality rate from 61 to 47 per 100,000). The estimated reduction for participants corrected for selection bias was 28% (13%-41%). Excluding deaths in breast cancer cases diagnosed after end of screening, these numbers became 26% and 31%, respectively.

CONCLUSIONS

There is additional benefit in reducing breast cancer mortality from the early detection of breast cancer through mammographic screening over and above the benefits arising from improvements in treatment alone.

Mammography interval and breast cancer mortality in women over the age of 75

The purpose of this study is to evaluate the relationship between mammography interval and breast cancer mortality among older women with breast cancer. The study population included 1,914 women diagnosed with invasive breast cancer at age 75 or later during their participation in the Women's health initiative, with an average follow-up of 4.4 years (3.1 SD). Cause of death was based on medical record review. Mammography interval was defined as the time between the last self-reported mammogram 7 or more months prior to diagnosis, and the date of diagnosis. Multivariable adjusted hazard ratios (HR) and 95 % confidence intervals (CIs) for breast cancer mortality and all-cause mortality were computed from Cox proportional hazards analyses. Prior mammograms were reported by 73.0 % of women from 7 months to ≤2 year of diagnosis (referent group), 19.4 % (>2 to <5 years), and 7.5 % (≥5 years or no prior mammogram). Women with the longest versus shortest intervals had more poorly differentiated (28.5 % vs. 22.7 %), advanced stage (25.7 % vs. 22.9 %), and estrogen receptor negative tumors (20.9 % vs. 13.1 %). Compared to the referent group, women with intervals of >2 to <5 years or ≥5 years had an increased risk of breast cancer mortality (HR 1.62, 95 % CI 1.03-2.54) and (HR 2.80, 95 % CI 1.57-5.00), respectively, p trend = 0.0002. There was no significant relationship between mammography interval and other causes of death. These results suggest a continued role for screening mammography among women 75 years of age and older.