Breast cancer screening for women ages 50 to 69 years a systematic review of observational evidence

Influence of Breast Cancer Awareness Month on Public Interest of Breast Cancer in High-Income Countries Between 2012 and 2022: Google Trends Analysis

BACKGROUND

Breast cancer is the most common cancer among women worldwide. High-income countries have a greater incidence and mortality rate of breast cancer than low-income countries. As a result, raising awareness about breast cancer is crucial in increasing the chances of early detection and treatment. Social media has evolved into an essential tool for Breast Cancer Awareness Month campaigns, allowing people to share their breast cancer stories and experiences while also providing a venue for education and support.

OBJECTIVE

The aim of this study was to assess the level of public interest in searches linked to breast cancer among a sample of high-income nations with a sizable internet user base from 2012 to 2022. We also sought to compare the proportional search volume for breast cancer during Breast Cancer Awareness Month with that during other months of the year.

METHODS

Google Trends was used to retrieve data on internet user search behaviors in the context of breast cancer from 2012 to 2022. Seven countries were evaluated in this study: Australia, Canada, Ireland, New Zealand, the United Kingdom, Saudi Arabia, and the United States, in addition to global data. Breast cancer relative search volume trends were analyzed annually, monthly, and weekly from 2012 to 2022. The annual percent change (APC) was calculated for each country and worldwide. Monthly and weekly data were used to identify potential trends.

RESULTS

A fluctuating pattern in APC rates was observed, with a notable increase in 2018 and a significant decrease in 2020, particularly in Saudi Arabia. Monthly analysis revealed a consistent peak in search volume during October (Breast Cancer Awareness Month) each year. Weekly trends over a 20-year period indicated significant decreases in Australia, Canada, New Zealand, and the United States, while increases were noted in Ireland. Heatmap analysis further highlighted a consistent elevation in median search volume during October across all countries.

CONCLUSIONS

These findings underscore the impact of Breast Cancer Awareness Month and suggest potential influences of governmental COVID-19 pandemic control measures in 2020 on internet search behavior.

The Positive Effect of an Online Appointment Portal on a Breast Cancer Screening Program

BACKGROUND

The adoption of web-based appointment methods by health care systems is increasing.

OBJECTIVES

This study primarily aimed to evaluate in the setting of an organized breast cancer screening program the actual usage of an online appointment portal by the target population, i.e., how the online tool was used (type and timing of the actions performed) and by whom (users' characteristics); the effect of coronavirus disease 2019 (COVID-19) on its usage was also investigated. The effect of adopting this tool on the attendance to breast cancer screening was contextually investigated.

METHODS

Electronic data records of 75,903 women (45-74 years old, residing in the territory of Bologna Local Health Authority) were retrospectively reviewed.

RESULTS

In total, 12.4% of women logged into the online portal at least once. Most of them (79.9%) rescheduled, 15.7% viewed, and 4.4% cancelled their own appointment. In addition, 40.6% of all rescheduling actions were performed by the online portal; the remaining was performed by the toll-free number/dedicated email address. The highest peak (13.8%) of web accesses was registered at 10 a.m. Monday to Friday, when the toll-free number service is available. Percentages of portal usage were higher: (1) among the younger women, of Italian nationality, and for the first time invited to mammographic screening (p < 0.0001), and (2) in the pandemic period versus the prepandemic period (12.5 vs. 8.6%, respectively; p < 0.001). Finally, when compared to not using, the online portal usage led to an overall reduction in the no-show rate of almost 20% (p < 0.0001).

CONCLUSION

The action mainly performed by using the online appointment portal was the appointment rescheduling. The usage of this tool had a positive effect on the no-show rate and it can be speculated that has led to a reduction of the request load to be handled by the center's screening staff. Finally, this study confirmed that the COVID-19 pandemic boosted the use of digital technologies.

Predicting Breast Cancer Risk for Women Veterans of African Ancestry in the Million Veteran Program

Breast cancer is a leading cause of cancer and, therefore, a major health threat for women in the United States and worldwide. We have seen over the years major advances in breast cancer prevention and care. Breast cancer screening with mammography leads to reduction in breast cancer mortality, and breast cancer prevention treatment with antiestrogens results in reduction in breast cancer incidence. More progress, however, is urgently needed for this common cancer that affects 1 in 11 American women in their lifetime. Not all women have the same breast cancer risk. A personalized approach is highly desirable as women with higher breast cancer risk may benefit from more intense breast cancer screening and/or prevention intervention while lower risk women may be spared with the cost, inconvenience, and emotional burden of these procedures. In addition to age, demographics, family history, lifestyle, and personal health, genetics is an important determinant of an individual's risk for breast cancer. Over the past 10 years, advances in cancer genomics identified multiple common genetic variants from population studies that collectively can contribute significantly to an individual's breast cancer risk. The effects of these genetic variants can be summarized as a "polygenic risk score" (PRS). We are among the first groups to prospectively evaluate the performance of these risk prediction instruments among women veterans of the Million Veteran Program (MVP). A 313-variant PRS (PRS313) predicted incident breast cancer for a prospective cohort of European (EUR) ancestry women veterans with an area under the receiver operating characteristic curve (AUC) of 0.622. The PRS313 performed less well for AFR ancestry however, with an AUC of 0.579. This is not surprising as most genome-wide association studies were conducted in people of European ancestry. This is an important area of health disparity and unmet need. The large population size and diversity of the MVP provide a unique and important opportunity to explore novel approaches to produce accurate and clinically useful genetic risk prediction instruments for minority populations.

Scientific uncertainty and perceived mammography benefits in women screened for breast cancer

PURPOSE

Personal aversion to scientific uncertainty may influence how women perceive the benefits of mammography, a breast cancer screening practice with conflicting scientific opinions and guidelines. Such associations may even exist among women who participate in screening.

METHODS

We evaluated the distribution of aversion to ambiguous medical information (AA-Med), using a 6-item scale capturing the level of agreement with statements about obtaining a cancer screening test with conflicting medical recommendations in 665 women (aged 40-60 years; 79.5% Hispanic) recruited during screening mammography appointments in New York City. We assessed the association of AA-Med with perceptions of benefits of mammography (breast cancer mortality reduction, worry reduction, early detection, treatment improvement) using multivariable logistic regression.

RESULTS

Over a quarter of participants expressed negative reactions to medical ambiguity about a cancer screening test (e.g., fear, lower trust in experts), but a majority endorsed intention to undergo screening. AA-Med was higher in women who were U.S.-born, non-Hispanic black, and had marginal to adequate health literacy, but there were no differences by clinical factors or screening experiences (e.g., family history, prior breast biopsy). Women with higher AA-Med were more likely to perceive treatment benefits from mammography (OR = 1.37, 95% CI = 0.99-1.90), but AA-Med was not associated with other perceived mammography benefits.

CONCLUSIONS

Aversion to uncertainty regarding cancer screening varies by sociodemographic characteristics but has limited associations with perceived mammography benefits in women who already participate in screening.

Supplemental Cancer Screening for Women With Dense Breasts: Guidance for Health Care Professionals

Mammography is the standard for breast cancer screening. The sensitivity of mammography in identifying breast cancer, however, is reduced for women with dense breasts. Thirty-eight states have passed laws requiring that all women be notified of breast tissue density results in their mammogram report. The notification includes a statement that differs by state, encouraging women to discuss supplemental screening options with their health care professionals (HCPs). Several supplemental screening tests are available for women with dense breast tissue, but no established guidelines exist to direct HCPs in their recommendation of preferred supplemental screening test. Tailored screening, which takes into consideration the patient's mammographic breast density and lifetime breast cancer risk, can guide breast cancer screening strategies that are more comprehensive. This review describes the benefits and limitations of the various available supplemental screening tests to guide HCPs and patients in choosing the appropriate breast cancer screening.

Screen-detected breast cancer is associated with better prognosis and survival compared to self-detected/symptomatic cases in a Chilean cohort of female patients

PURPOSE

The implementation of national breast cancer (BC) screening programs in Latin America has been rather inconsistent. Instead, most countries have opted for "opportunistic" mammogram screenings on the population at risk. Our study assessed and compared epidemiological, clinical factors, and survival rates associated with BC detected by screening (SDBC) or self-detected/symptomatic (non-SDBC) in Chilean female patients.

METHODS

Registry-based cohort study that included non-metastatic BC (stage I/II/III) patients diagnosed between 1993 and 2020, from a public hospital (PH) and a private university cancer center (PC). Epidemiological and clinical data were obtained from medical records.

RESULTS

A total of 4559 patients were included. Most patients (55%; n = 2507) came from PH and were diagnosed by signs/symptoms (non-SDBC; n = 3132, 68.6%); these patients displayed poorer overall (OS) and invasive disease-free survival (iDFS) compared to SDBC. Importantly, the proportion of stage I and "luminal" BC (HR + /HER2 -) were significantly higher in SDBC vs. non-SDBC. Finally, using a stage/subset-stratified age/insurance-adjusted model, we found that non-SDBC cases are at a higher risk of death (HR:1.75; p < 0.001). In contrast, patients with PC health insurance have a lower risk of death (HR: 0.60; p < 0.001).

CONCLUSION

We confirm previous studies that report better prognosis/survival on SDBC patients. This is probably due to a higher proportion of stage I and luminal-A cases versus non-SDBC. In turn, the survival benefit observed in patients with PC health insurance might be attributed to a larger proportion of SDBC. Our data support the implementation of a systematic BC screening program in Chile to improve patient prognosis and survival rates.

Defining breast cancer awareness and identifying barriers to breast cancer awareness for women with an intellectual disability: A review of the literature

INTRODUCTION

Incidence rates for developing breast cancer are similar for women regardless of intellectual ability. However, women with an intellectual disability present with advanced breast cancers, which often have a poor prognosis.

METHOD

A structured narrative review of the literature was performed to explore the concepts of breast awareness and breast cancer awareness and subsequently, identify barriers to breast cancer awareness encountered by women with an intellectual disability.

RESULTS

A total of 22 studies involving people with varying levels of intellectual disability informed this review. The barriers to breast cancer awareness encountered by women with an intellectual disability include: lack of their understanding, the role of the carer and literacy issues.

CONCLUSION

Identifying the barriers to breast cancer awareness for women with an intellectual disability will help to facilitate breast cancer awareness which has the potential to result in better long-term outcomes through an early diagnosis of breast cancer.

Factors Associated with Breast Cancer Awareness in Thai Women

Background:

Breast cancer is the most common cancer in women worldwide. In south-east Asia, both the incidence and mortality rates of breast cancer are on the rise, and the latter is likely due to the limited access to large-scale community screening program in these resource-limited countries. Breast cancer awareness is an important tool which may, through increasing breast self-examination and the seeking of clinical examination, reduce breast cancer mortality. Investigating factors associated with breast cancer awareness of women is likely to help identify those at risk, and provide insights into developing effective health promotion interventions.

Objective:

To investigate factors associated with breast cancer awareness in Thai women.

Methods:

A cross-sectional sample of Thai women aged 20-64 years was collected during August to October, 2015 from two provinces of southern Thailand (Surat Thani and Songkla). A questionnaire including the Breast Cancer Awareness Scale along with demographic characteristics was administered and Proportional Odds Logistic regression was then used to investigate factors associated with breast cancer awareness.

Results:

In total, 660 Thai women participated in this study. Factors most often associated with the various breast cancer awareness domains were age and rurality. While rural women had poorer knowledge of breast cancer signs and symptoms, they also had lower levels of perceived barriers and considerably better breast cancer awareness behaviors.

Conclusion:

Despite lower knowledge of breast cancer risk factors and no evidence of better knowledge of signs and symptoms, we found rural Thai women had considerably better breast cancer awareness behavior. This may be due to these women’s lower levels of perceived barriers to breast cancer screening services. Indeed this suggests, at least in Thai women, that interventions aimed at lowering perceived barriers rather than enhancing disease knowledge may be more successful in engaging women with breast cancer screening services and increasing breast self-examination.

An educational intervention based on the extended parallel process model to improve attitude, behavioral intention, and early breast cancer diagnosis: a randomized trial

BACKGROUND

Breast cancer is an important public health problem worldwide. This study aimed to assess the effectiveness of an educational intervention based on fear appeals using the extended parallel process model (EPPM) to improve attitudes, intention, and early breast cancer diagnosis in Iranian women.

METHODS

This was a cluster-randomized trial conducted in Tehran, Iran. A sample of women 40 years old and above was recruited and assigned either to intervention group or to control group. The intervention group received two pamphlets containing fear appeals specially designed for this study using the EPPM. The control group received nothing. The primary outcomes were changes in attitude, behavioral intention, and early breast cancer diagnosis. Participants responded to a questionnaire before intervention and at 3 months follow-up assessments. Independent t-tests and paired t-tests were used for comparison.

RESULT

In all, 600 women were entered into the study (277 in the intervention group and 323 in the control group). Of these, 162 were lost to follow-up assessment. Thus, the analysis was restricted to those for whom both baseline and follow-up information was available (n=438). The mean age of participants was 53.2 (SD=9.45) years, and the mean year education of participants was 9.4 (SD=4.12) years. There were no significant differences between two groups regarding demographic variables. However, comparing outcome variables (attitude, intention, and early breast cancer diagnosis) at baseline and follow-up assessments, we found that the intervention group showed significant improvements in attitude and intention (P=0.01 and P=0.001, respectively), but no significant improvement was observed for early breast cancer diagnosis (P=0.78). The control group did not show any changes.

CONCLUSION

The findings showed that fear appeals could not influence early breast cancer diagnosis among women. However, significant changes were observed for attitude and behavioral intention.

Effect of organized mammography screening on breast cancer mortality: A population-based cohort study in Norway

We aimed to estimate the effect of organized mammography screening on incidence-based breast cancer mortality by comparing changes in mortality among women eligible for screening to concurrent changes in younger and older ineligible women. In a county-wise balanced, open-cohort study, we used birth cohorts (1896-1982) to construct three age groups in both the historical and screening period: women eligible for screening, and younger or older women ineligible for screening. We included women diagnosed with breast cancer who died within the same age-period group during 1987-2010 (n = 4,903). We estimated relative incidence-based mortality rate ratios (relative MRR) comparing temporal changes in eligible women to concurrent changes in ineligible women. Additionally, we conducted analyses comparing the change in eligible women to younger, ineligible women with either continued accrual and follow-up period (eligible women only) or continued follow-up period. All three age groups experienced a reduction in mortality, but the decrease among eligible women was about the same among ineligible women (relative MRR = 1.05, 95% CI: (0.94-1.18)). Varying the definition of follow-up yielded similar results. Mammography screening was not associated with a larger breast cancer mortality reduction in women eligible relative to ineligible women.

A cohort study of mammography screening finds that comorbidity measures are insufficient for controlling selection bias

OBJECTIVE

To examine the potential of claims-based comorbidity measures for controlling selection bias in observational studies of mammography screening.

STUDY DESIGN AND SETTING

Based on claims data of a large German Statutory Health Insurance fund, the single comorbidities considered by the Charlson, Elixhauser, Multipurpose Australian Comorbidity Scoring System, and M3 comorbidity measures were identified for mammography screening participants and nonparticipants. Total death rates within 4 years after screening invitation were compared. Cox proportional hazards regressions were performed unadjusted and adjusted for age, federal state of residence, and comorbidity.

RESULTS

Among 1,247,919 insured women aged 50-68 years (56.2% participants), 10,311 participants (death rate 375.8/100,000 person-years) and 18,113 nonparticipants (death rate 854.8/100,000 person-years) died from any cause during the follow-up. The unadjusted hazard ratio (HR) for death from any cause for participants vs. nonparticipants was 0.44 (99.9% confidence interval 0.42-0.46). Adjustments attenuated the HR to a maximum of 0.52 (0.50-0.54).

CONCLUSION

The lower short-term all-cause mortality among participants cannot be explained by mammography screening effects and should be interpreted as selection bias. Adjusting for comorbidities only slightly attenuated this bias. Future studies should examine whether claims data include further information that is beneficial to adequately control selection bias in observational studies of mammography screening.

Overdiagnosis of breast cancer in population screening: does it make breast screening worthless?

The risk of breast cancer (BC) overdiagnosis attributed to mammography screening is an unresolved issue, complicated by heterogeneity in the methodology of quantifying its magnitude, and both political and scientific elements surrounding interpretation of the evidence on this phenomenon. Evidence from randomized trials and also from observational studies shows that mammography screening reduces the risk of BC death; similarly, these studies provide sufficient evidence that overdiagnosis represents a serious harm from population breast screening. For both these outcomes of screening, BC mortality reduction and overdiagnosis, estimates of magnitude vary between studies however overdiagnosis estimates are associated with substantial uncertainty. The trade-off between the benefit and the collective harms of BC screening, including false-positives and overdiagnosis, is more finely balanced than initially recognized, however the snapshot of evidence presented on overdiagnosis does not mean that breast screening is worthless. Future efforts should be directed towards (a) ensuring that any changes in the implementation of BC screening optimize the balance between benefit and harms, including assessing how planned or actual changes modify the risk of overdiagnosis; (b) informing women of all the outcomes that may affect them when they participate in screening using well-crafted and balanced information; and (c) investing in research that will help define and reduce the ensuing overtreatment of screen-detected BC.

Effect of organised mammography screening on stage-specific incidence in Norway: population study

Background:

We aimed to estimate the effect of organised mammography screening on breast cancer stage distribution by comparing changes in women eligible for screening, based on birth cohort, to the concurrent changes in younger, ineligible women.

Methods:

In an open cohort study in Norway, which introduced national mammography screening county-by-county from 1995 to 2004, we identified women (n=49 883) diagnosed with in situ or invasive breast cancer (ICD10 codes: D05 or C50) during the period 1987–2011 and born between 1917 and 1980. We estimated relative incidence rate ratios (rIRRs) comparing the development in the screening vs historic group to the younger vs younger historic group.

Results:

Including the compensatory drop, eligible women experienced a 68% higher increase in localised cancers (rIRR=1.68, 95% confidence interval (CI): 1.51–1.87) than younger women, while the increase in incidence of advanced cancers was similar (rIRR=1.11, 95% CI: 0.90–1.36). Excluding the prevalence round, eligible women experienced a 60% higher increase in localised cancers (rIRR=1.60, 95% CI: 1.42–1.79), while the increase in incidence of advanced cancers remained similar (rIRR=1.08, 95% CI: 0.86–1.35).

Conclusions:

Introduction of organised mammography screening was followed by a significant increase in localised and no change in advanced-stage cancers in women eligible for screening relative to younger, ineligible women.

Four Principles to Consider Before Advising Women on Screening Mammography

This article reviews four important screening principles applicable to screening mammography in order to facilitate informed choice. The first principle is that screening may help, hurt, or have no effect. In order to reduce mortality and mastectomy rates, screening must reduce the rate of advanced disease, which likely has not happened. Through overdiagnosis, screening produces substantial harm by increasing both lumpectomy and mastectomy rates, which offsets the often-promised benefit of less invasive therapy. Next, all-cause mortality is the most reliable way to measure the efficacy of a screening intervention. Disease-specific mortality is biased due to difficulties in attribution of cause of death and to increased mortality due to overdiagnosis and the resulting overtreatment with radiotherapy and chemotherapy. To enhance participation, the benefit from screening is often presented in relative instead of absolute terms. Third, some screening statistics must be interpreted with caution. Increased survival time and the percentage of early-stage tumors at detection sound plausible, but are affected by lead-time and length biases. In addition, analyses that only include women who attend screening cannot reliably correct for selection bias. The final principle is that accounting for tumor biology is important for accurate estimates of lead time, and the potential benefit from screening. Since “early detection” is actually late in a tumor's lifetime, the time window when screen detection might extend a woman's life is narrow, as many tumors that can form metastases will already have done so. Instead of encouraging screening mammography, physicians should help women make an informed decision as with any medical intervention.

Quantifying and monitoring overdiagnosis in cancer screening: a systematic review of methods

OBJECTIVE

To determine the optimal method for quantifying and monitoring overdiagnosis in cancer screening over time.

DESIGN

Systematic review of primary research studies of any design that quantified overdiagnosis from screening for nine types of cancer. We used explicit criteria to critically appraise individual studies and assess strength of the body of evidence for each study design (double blinded review), and assessed the potential for each study design to accurately quantify and monitor overdiagnosis over time.

DATA SOURCES

PubMed and Embase up to 28 February 2014; hand searching of systematic reviews.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

English language studies of any design that quantified overdiagnosis for any of nine common cancers (prostate, breast, lung, colorectal, melanoma, bladder, renal, thyroid, and uterine); excluded case series, case reports, and reviews that only reported results of other studies.

RESULTS

52 studies met the inclusion criteria. We grouped studies into four methodological categories: (1) follow-up of a well designed randomized controlled trial (n=3), which has low risk of bias but may not be generalizable and is not suitable for monitoring; (2) pathological or imaging studies (n=8), drawing conclusions about overdiagnosis by examining biological characteristics of cancers, a simple design limited by the uncertain assumption that the measured characteristics are highly correlated with disease progression; (3) modeling studies (n=21), which can be done in a shorter time frame but require complex mathematical equations simulating the natural course of screen detected cancer, the fundamental unknown question; and (4) ecological and cohort studies (n=20), which are suitable for monitoring over time but are limited by a lack of agreed standards, by variable data quality, by inadequate follow-up time, and by the potential for population level confounders. Some ecological and cohort studies, however, have addressed these potential weaknesses in reasonable ways.

CONCLUSIONS

Well conducted ecological and cohort studies in multiple settings are the most appropriate approach for quantifying and monitoring overdiagnosis in cancer screening programs. To support this work, we need internationally agreed standards for ecological and cohort studies and a multinational team of unbiased researchers to perform ongoing analysis.

Successful first round results of a Turkish breast cancer screening program with mammography in Bahcesehir, Istanbul

BACKGROUND

The Bahcesehir Breast Cancer Screening Project is the first organized population based breast cancer mammographic screening project in Turkey. The objective of this prospective observational study was to demonstrate the feasibility of a screening program in a developing country and to determine the appropriate age (40 or 50 years old) to start with screening in Turkish women.

MATERIALS AND METHODS

Between January 2009 to December 2010, a total of 3,758 women aged 40-69 years were recruited in this prospective study. Screening was conducted biannually, and five rounds were planned. After clinical breast examination (CBE), two-view mammograms were obtained. True positivity, false positivity, positive predictive values (PPV) according to ACR, cancer detection rate, minimal cancer detection rate, axillary node positivity and recall rate were calculated. Breast ultrasound and biopsy were performed in suspicious cases.

RESULTS

Breast biopsy was performed in 55 patients, and 18 cancers were detected in the first round. The overall cancer detection rate was 4.8 per 1,000 women. Most of the screened women (54%) and detected cancers (56%) were in women aged 40- 49. Ductal carcinoma in situ (DCIS) and stage I cancer and axillary node positivity rates were 22%, 61%, and 16.6%, respectively. The positive predictivity for biopsy was 32.7%, whereas the overall recall rate was 18.4 %.

CONCLUSIONS

Preliminary results of the study suggest that population based organized screening are feasible and age of onset of mammographic screening should be 40 years in Turkey.

Screening mammography--early detection or over-diagnosis? Contribution from Australian data

OBJECTIVE

The aim of this review was to examine the benefits and harms of organized screening mammography, with particular reference to data from Australia.

METHODS

Published literature was examined relating to the impact of screening mammography on breast cancer-specific mortality, the trends in use of adjuvant treatments for breast cancer, the effectiveness of adjuvant treatment in terms of breast cancer-specific mortality, the impact of breast cancer treatment on non-breast cancer mortality and the magnitude of the issue of over-diagnosis.

RESULTS

Most of the recent reduction in breast cancer-specific mortality is explained by use of adjuvant therapy rather than screening mammography. The impact of screening mammography in countries where women present with early disease and have access to adjuvant treatment is modest. There is a wide range of estimates for the magnitude of over-diagnosis. All-cause mortality (rather than breast cancer-specific mortality) should be used when assessing the impact of mammographic screening as otherwise the harm of breast cancer treatment in women who are over-diagnosed will be missed.

CONCLUSIONS

The benefits and harms of screening mammography are finely balanced. The impact of screening mammography is at best neutral but may result in overall harm. Women should be informed of the issue of over-diagnosis. It is time to review whether organized mammographic screening programs should continue.

Multi-centre analysis of incidental findings on low-resolution CT attenuation correction images

OBJECTIVE

To review new incidental findings detected on low-resolution CT attenuation correction (CTAC) images acquired during single-photon emission CT (SPECT-CT) myocardial perfusion imaging (MPI) and to determine whether the CTAC images had diagnostic value and warrant reporting.

METHODS

A multicentre study was performed in four UK nuclear medicine departments. CTAC images acquired as part of MPI performed using SPECT were evaluated to identify incidental findings. New findings considered to be clinically significant were evaluated further. Positive predictive value (PPV) was determined at the time of definitive diagnosis.

RESULTS

Of 1819 patients studied, 497 (27.3%) had a positive CTAC finding. 51 (2.8%) patients had findings that were clinically significant at the time of the CTAC report and had not been previously diagnosed. Only four (0.2%) of these were potentially detrimental to patient outcome.

CONCLUSION

One centre had a PPV of 0%, and the study suggests that these CTAC images should not be reported. Two centres with more modern equipment had low PPVs of 0% and 6%, respectively, and further research is suggested prior to drawing a conclusion. The centre with best quality CT had a PPV of 67%, and the study suggests that CTAC images from this equipment should be reported.

ADVANCES IN KNOWLEDGE

This study is unique compared with previous studies that have reported only the potential to identify incidental findings on low-resolution CT images. This study both identifies and evaluates new clinically significant incidental findings, and it demonstrates that the benefit of reporting the CTAC images depends on the type of equipment used.

[Can a mobile phone short message increase participation in breast cancer screening programmes?]

OBJECTIVE

To evaluate the impact of a mobile phone short message on women's uptake in a breast cancer screening programme.

METHODS

A total of 703 women from a Basic Health Area of Barcelona, and with a mobile phone number registered, were invited to participate in a breast cancer screening programme between 25 January 2011 and 22 March 2011. The control group (n=470) followed the usual appointment track, and the intervention group (n=233) received, after the first letter of invitation, a mobile phone short message reminder. The differences between the two groups were analysed, comparing the uptake rates according to age, educational level, and participation in previous round, as well as the number of re-invitation calls to non-attenders according to uptake, age and level of education;and the percentages of exclusions of both groups.

RESULTS

The intervention group had a greater uptake than the control group (78.1% vs. 72.3%), with a significant trend observed in the 55-59 years age group (P=.036) and the low secondary educational level (P=.014).The intervention group mean of re-invitation calls of non-attenders lower than the control group (.41 vs. .65, P<.05), a pattern observed in all the categories of the independent variables, and among younger age groups, lower and middle educational levels, and previously participating women (.09 vs. .19, P=.012).

CONCLUSIONS

The inclusion of a mobile phone short message in a breast cancer screening programme may increase uptake rates and lead to a management improvement.

Screening mammography & breast cancer mortality: meta-analysis of quasi-experimental studies

Background

The magnitude of the benefit associated with screening has been debated. We present a meta-analysis of quasi-experimental studies on the effects of mammography screening.

Methods

We searched MEDLINE/PubMed and Embase for articles published through January 31, 2013. Studies were included if they reported: 1) a population-wide breast cancer screening program using mammography with 5+ years of data post-implementation; 2) a comparison group with equal access to therapies; and 3) breast cancer mortality. Studies excluded were: RCTs, case-control, or simulation studies. We defined quasi-experimental as studies that compared either geographical, historical or birth cohorts with a screening program to an equivalent cohort without a screening program. Meta-analyses were conducted in Stata using the metan command, random effects. Meta-analyses were conducted separately for ages screened: under 50, 50 to 69 and over 70 and weighted by population and person-years.

Results

Among 4,903 published papers that were retrieved, 19 studies matched eligibility criteria. Birth cohort studies reported a significant benefit for women screened <age 50, but not for women screened ages 50–69. Significant reductions in breast cancer mortality were observed in historical comparisons. For geographical comparisons, there was a significant 20% reduction in mortality for women <age 50 and a significant 21–22% reduction for women ages 50–69. Studies that tested the interaction of geographical and historical comparisons produced a pooled, significant 13–17% reduction in incident breast cancer mortality for women ages 50–69, but the effects in most individual studies were non-significant. All studies of women ages 70+ were non-significant.

Conclusions

Mammography screening may have modest effects on cancer mortality between the ages of 50 and 69 and non-significant effects for women older than age 70. Results are consistent with meta-analyses of RCTs. Effects on total mortality could not be assessed because of the limited number of studies.

Breast cancer screening halves the risk of breast cancer death: a case-referent study

Large-scale epidemiologic studies have consistently demonstrated the effectiveness of mammographic screening programs, however the benefits are still subject to debate. We estimated the effect of the Dutch screening program on breast cancer mortality. In a large multi-region case-referent study, we identified all breast cancer deaths in 2004 and 2005 in women aged 50-75 who had been invited for screening (cases). Cases were individually matched to referents from the population invited to screening. Conditional logistic regression was used to estimate the odds ratio (OR) of breast cancer death according to individual screening history. The OR was adjusted for self-selection bias using regional correction factors for the difference in baseline risk for breast cancer death between screened and unscreened women. A total of 1233 cases and 2090 referents were included in this study. We found a 58% reduction in breast cancer mortality in screened versus unscreened women (adjusted OR = 0.42, 95% CI 0.33-0.53). Screening, i.e. early detection and treatment, has resulted in a substantial reduction in breast cancer mortality, indicating that the Dutch breast cancer screening program is highly effective.

Phosphorylation of NTRK1 at Y674/Y675 induced by TP53-dependent repression of PTPN6 expression: a potential novel prognostic marker for breast cancer

We have identified a ligand-independent mechanism whereby the tumor suppressor, TP53, induces nerve growth factor receptor, NTRK1, phosphorylation at Y674/Y675 (NTRK1-pY674/pY675), via the repression of the NTRK1-phosphatase, PTPN6. This results in suppression of breast cancer cell proliferation. In this investigation, we aimed to establish whether perturbation of the wild-type TP53-NTRK1-pY674/pY675-PTPN6 pathway has an impact on disease-free survival of breast cancer patients without neo-adjuvant treatment. A total of 308 tumor samples were stained for NTRK1, NTRK1-pY674/pY675, PTPN6, and TP53 expression. Association between expression levels and disease-free survival was determined by the univariate/multivariate and Kaplan-Meir methods of analysis. DNA from tumors was sequenced to identify mutant or wild-type TP53. Tumors expressing NTRK1-pY674/pY675 but with undetectable or low levels of PTPN6 and TP53 were associated with prolonged 5, 10, and 15 years' disease-free survival by 48%, 36%, and 37%, respectively, in the multivariate analysis (P<0.05). A similar result was observed in tumors expressing wild-type TP53, NTRK1-pY674/pY675, and low or undetectable levels of PTPN6. Given that estrogen receptor-positive breast cancers encode wild-type TP53, we analyzed this expression pattern in these tumors. Multivariate analysis showed that it was significantly and independently predictive of prolonged survival by 66%, 70%, and 84%, respectively, (P<0.05). The Kaplan-Meir method demonstrated that NTRK1-pY674/pY675 together with undetectable or low levels of PTPN6 correlated with 59% probability of disease-free survival (median survival 15 years), compared with 7% probability of disease-free survival (median survival 4.5 years) when absent. In luminal A tumors, the presence of this pattern was estimated to have a 61% probability of disease-free survival (median survival 15 years), compared with 6% probability of disease-free survival (median survival 3 years) when it was absent. These results strongly suggest that expression of NTRK1-pY674/pY675 together with wild-type TP53 and low levels of PTPN6 expression are predictors of improved disease-free survival and that they could be useful biomarkers to predict clinical outcome.

Breast cancer screening: review of benefits and harms, and recommendations for developing and low-income countries

Breast cancer is the most common cancer in women worldwide. The disease remains a public health concern as recent evidence indicates that the breast cancer burden has increased mainly in developing and low-income countries (DLICs). Despite the demonstrated benefits, the debate about the real benefits and harms of breast cancer screening is ongoing. Many experts believe that the benefits of screening, in terms of reduced breast cancer mortality, outweigh the harms, whereas others think the opposite. In this review, we assess the clinical utility of available screening modalities, present evidence, overdiagnosis, cost-effectiveness, and other pertinent issues. We also examine relevant data from DLICs to underscore the barriers and challenges that impede implementation of screening strategies in those populations. We also provide recommendations concerning rational preventive strategies for breast cancer control for women in DLICs.

The impact of mammographic screening on breast cancer mortality in Europe: a review of observational studies

OBJECTIVES

To assess the impact of population-based mammographic screening on breast cancer mortality in Europe, considering different methodologies and limitations of the data.

METHODS

We conducted a systematic literature review of European trend studies (n = 17), incidence-based mortality (IBM) studies (n = 20) and case-control (CC) studies (n = 8). Estimates of the reduction in breast cancer mortality for women invited versus not invited and/or for women screened versus not screened were obtained. The results of IBM studies and CC studies were each pooled using a random effects meta-analysis.

RESULTS

Twelve of the 17 trend studies quantified the impact of population-based screening on breast cancer mortality. The estimated breast cancer mortality reductions ranged from 1% to 9% per year in studies reporting an annual percentage change, and from 28% to 36% in those comparing post- and prescreening periods. In the IBM studies, the pooled mortality reduction was 25% (relative risk [RR] 0.75, 95% confidence interval [CI] 0.69-0.81) among invited women and 38% (RR 0.62, 95% CI 0.56-0.69) among those actually screened. The corresponding pooled estimates from the CC studies were 31% (odds ratio [OR] 0.69, 95% CI 0.57-0.83), and 48% (OR 0.52, 95% CI 0.42-0.65) adjusted for self-selection.

CONCLUSIONS

Valid observational designs are those where sufficient longitudinal individual data are available, directly linking a woman's screening history to her cause of death. From such studies, the best 'European' estimate of breast cancer mortality reduction is 25-31% for women invited for screening, and 38-48% for women actually screened. Much of the current controversy on breast cancer screening is due to the use of inappropriate methodological approaches that are unable to capture the true effect of mammographic screening.

The benefits and harms of breast cancer screening: an independent review

Whether breast cancer screening does more harm than good has been debated extensively. The main questions are how large the benefit of screening is in terms of reduced breast cancer mortality and how substantial the harm is in terms of overdiagnosis, which is defined as cancers detected at screening that would not have otherwise become clinically apparent in the woman's lifetime. An independent Panel was convened to reach conclusions about the benefits and harms of breast screening on the basis of a review of published work and oral and written evidence presented by experts in the subject. To provide estimates of the level of benefits and harms, the Panel relied mainly on findings from randomised trials of breast cancer screening that compared women invited to screening with controls not invited, but also reviewed evidence from observational studies. The Panel focused on the UK setting, where women aged 50-70 years are invited to screening every 3 years. In this Review, we provide a summary of the full report on the Panel's findings and conclusions. In a meta-analysis of 11 randomised trials, the relative risk of breast cancer mortality for women invited to screening compared with controls was 0·80 (95% CI 0·73-0·89), which is a relative risk reduction of 20%. The Panel considered the internal biases in the trials and whether these trials, which were done a long time ago, were still relevant; they concluded that 20% was still a reasonable estimate of the relative risk reduction. The more reliable and recent observational studies generally produced larger estimates of benefit, but these studies might be biased. The best estimates of overdiagnosis are from three trials in which women in the control group were not invited to be screened at the end of the active trial period. In a meta-analysis, estimates of the excess incidence were 11% (95% CI 9-12) when expressed as a proportion of cancers diagnosed in the invited group in the long term, and 19% (15-23) when expressed as a proportion of the cancers diagnosed during the active screening period. Results from observational studies support the occurrence of overdiagnosis, but estimates of its magnitude are unreliable. The Panel concludes that screening reduces breast cancer mortality but that some overdiagnosis occurs. Since the estimates provided are from studies with many limitations and whose relevance to present-day screening programmes can be questioned, they have substantial uncertainty and should be regarded only as an approximate guide. If these figures are used directly, for every 10,000 UK women aged 50 years invited to screening for the next 20 years, 43 deaths from breast cancer would be prevented and 129 cases of breast cancer, invasive and non-invasive, would be overdiagnosed; that is one breast cancer death prevented for about every three overdiagnosed cases identified and treated. Of the roughly 307,000 women aged 50-52 years who are invited to begin screening every year, just over 1% would have an overdiagnosed cancer in the next 20 years. Evidence from a focus group organised by Cancer Research UK and attended by some members of the Panel showed that many women feel that accepting the offer of breast screening is worthwhile, which agrees with the results of previous similar studies. Information should be made available in a transparent and objective way to women invited to screening so that they can make informed decisions.

Breast cancer screening: the questions answered

Early detection of cancer has long been thought to be the first step towards eradicating the mortality associated with the disease. National screening programmes for breast cancer have been implemented in many countries. However, there is controversy regarding the efficacy and optimal methods of screening, which is regularly discussed in articles, at conferences and is apparent in conflicting guidelines. In this article, Nature Reviews Clinical Oncology asks four experts their opinions on some of the pressing questions associated with breast cancer screening.