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

Systematic review and meta-analysis of prognostic characteristics for breast cancers in populations with digital vs film mammography indicate the transition may have increased both early detection and overdiagnosis

OBJECTIVES

Film mammography has been replaced by digital mammography in breast screening programs globally. This led to a small increase in the rate of detection, but whether the detection of clinically important cancers increased is uncertain. We aimed to assess the impact on tumor characteristics of screen-detected and interval breast cancers.

STUDY DESIGN AND SETTING

We searched seven databases from inception to October 08, 2023, for publications comparing film and digital mammography within the same population of asymptomatic women at population (average) risk of breast cancer. We recorded reported tumor characteristics and assessed risk of bias using the Risk Of Bias In Non-randomised Studies - of Interventions tool. We synthesized results using meta-analyses of random effects.

RESULTS

Eighteen studies were included in the analysis from 8 countries, including 11,592,225 screening examinations (8,117,781 film; 3,474,444 digital). There were no differences in tumor size, morphology, grade, node status, receptor status, or stage in the pooled differences for screen-detected and interval invasive cancer tumor characteristics. There were statistically significant increases in screen-detected ductal carcinoma in situ (DCIS) across all grades: 0.05 (0.00-0.11), 0.14 (0.05-0.22), and 0.19 (0.05-0.33) per 1000 screens for low, intermediate, and high-grade DCIS, respectively. There were similar (non-statistically significant) increases in screen-detected invasive cancer across all grades.

CONCLUSION

The increased detection of all grades of DCIS and invasive cancer may indicate both increased early detection of more aggressive disease and increased overdiagnosis.

Precision Oncology in Breast Cancer Surgery

Outcomes for patients with breast cancer have improved over time due to increased screening and the availability of more effective therapies. It is important to recognize that breast cancer is a heterogeneous disease that requires treatment based on molecular characteristics. Early endpoints such as pathologic complete response correlate with event-free survival, allowing the opportunity to consider de-escalation of certain cancer treatments to avoid overtreatment. This article discusses clinical trials of tailoring treatment (eg, I-SPY2) and screening (eg, WISDOM) to individual patients based on their unique risk features.

Implementation considerations for risk-tailored cancer screening in the population: A scoping review

BACKGROUND

Risk-tailored screening has emerged as a promising approach to optimise the balance of benefits and harms of existing population cancer screening programs. It tailors screening (e.g., eligibility, frequency, interval, test type) to individual risk rather than the current one-size-fits-all approach of most organised population screening programs. However, the implementation of risk-tailored cancer screening in the population is challenging as it requires a change of practice at multiple levels i.e., individual, provider, health system levels. This scoping review aims to synthesise current implementation considerations for risk-tailored cancer screening in the population, identifying barriers, facilitators, and associated implementation outcomes.

METHODS

Relevant studies were identified via database searches up to February 2023. Results were synthesised using Tierney et al. (2020) guidance for evidence synthesis of implementation outcomes and a multilevel framework.

RESULTS

Of 4138 titles identified, 74 studies met the inclusion criteria. Most studies in this review focused on the implementation outcomes of acceptability, feasibility, and appropriateness, reflecting the pre-implementation stage of most research to date. Only six studies included an implementation framework. The review identified consistent evidence that risk-tailored screening is largely acceptable across population groups, however reluctance to accept a reduction in screening frequency for low-risk informed by cultural norms, presents a major barrier. Limited studies were identified for cancer types other than breast cancer.

CONCLUSIONS

Implementation strategies will need to address alternate models of delivery, education of health professionals, communication with the public, screening options for people at low risk of cancer, and inequity in outcomes across cancer types.

Communicating the results of risk-based breast cancer screening through visualizations of risk: a participatory design approach

BACKGROUND

Risk-based breast cancer (BC) screening raises new questions regarding information provision and risk communication. This study aimed to: 1) investigate women's beliefs and knowledge (i.e., mental models) regarding BC risk and (risk-based) BC screening in view of implications for information development; 2) develop novel informational materials to communicate the screening result in risk-based BC screening, including risk visualizations of both quantitative and qualitative information, from a Human-Centered Design perspective.

METHODS

Phase 1: Interviews were conducted (n = 15, 40-50 years, 5 lower health literate) on women's beliefs about BC risk and (risk-based) BC screening. Phase 2: In three participatory design sessions, women (n = 4-6 across sessions, 40-50 years, 2-3 lower health literate) made assignments and created and evaluated visualizations of risk information central to the screening result. Prototypes were evaluated in two additional sessions (n = 2, 54-62 years, 0-1 lower health literate). Phase 3: Experts (n = 5) and women (n = 9, 40-74 years) evaluated the resulting materials. Two other experts were consulted throughout the development process to ensure that the content of the information materials was accurate. Interviews were transcribed literally and analysed using qualitative thematic analysis, focusing on implications for information development. Notes, assignments and materials from the participatory design sessions were summarized and main themes were identified.

RESULTS

Women in both interviews and design sessions were positive about risk-based BC screening, especially because personal risk factors would be taken into account. However, they emphasized that the rationale of risk-based screening and classification into a risk category should be clearly stated and visualized, especially for higher- and lower-risk categories (which may cause anxiety or feelings of unfairness due to a lower screening frequency). Women wanted to know their personal risk, preferably visualized in an icon array, and wanted advice on risk reduction and breast self-examination. However, most risk factors were considered modifiable by women, and the risk factor breast density was not known, implying that information should emphasize that BC risk depends on multiple factors, including breast density.

CONCLUSIONS

The information materials, including risk visualizations of both quantitative and qualitative information, developed from a Human-Centered Design perspective and a mental model approach, were positively evaluated by the target group.

Integrating clinical research in an operative screening and diagnostic breast imaging department: First experience, results and perspectives using microwave imaging

Rationale and objectives

Clinical research is crucial for evaluating new medical procedures and devices. It is important for healthcare units and hospitals to minimize the disruptions caused by conducting clinical studies; however, complex clinical pathways require dedicated recruitment and study designs.This work presents the effective introduction of novel microwave breast imaging (MBI), via MammoWave apparatus, into the clinical routine of an operative screening and diagnostic breast imaging department for conducting a multicentric clinical study.

Materials and methods

Microwave breast imaging, using MammoWave apparatus, was performed on volunteers coming from different clinical pathways. Clinical data, comprising demographics and conventional radiologic reports (used as reference standard), was collected; a satisfaction questionnaire was filled by every volunteer. Microwave images were analyzed by an automatic clinical decision support system, which quantified their corresponding features to discriminate between breasts with no relevant radiological findings (NF) and breasts with described findings (WF).

Results

Conventional breast imaging (DBT, US, MRI) and MBI were performed and adapted to assure best clinical practices and optimum pathways. 180 volunteers, both symptomatic and asymptomatic, were enrolled in the study. After microwave images' quality assessment, 48 NF (15 dense) and 169 WF (88 dense) breasts were used for the prospective study; 48 (18 dense) breasts suffered from a histology-confirmed carcinoma. An overall sensitivity of 85.8 % in breasts lesions' detection was achieved by the microwave imaging apparatus.

Conclusion

An optimum recruitment strategy was implemented to assess MBI. Future trials may show the clinical usefulness of microwave imaging, which may play an important role in breast screening.

Epidemiology of Breast Cancer Mortality in Kazakhstan, trends and Geographic Distribution

BACKGROUND

According to the International Agency for Research on Cancer, ongoing demographic changes will lead to an increase in the number of deaths from breast cancer (BC) per year in the vast majority of regions. In 2040 it is expected that 1.04 million people worldwide will die from this malignancy, including 2,380 women in Kazakhstan.

METHODS

The retrospective study (2009-2018) was done using descriptive and analytical methods of oncoepidemiology. The extensive, crude and age-specific incidence rates are determined according to the generally accepted methodology used in sanitary statistics. The data were used to calculate the average percentage change (APС) using the Joinpoint regression analysis to determine the trend over the study period.

RESULTS

During 10 years 12,958 women died from BC. An average age of the death was 61.6 years (95%CI=60.6-62.6) and tended to increase (APC=+0.6%, R2=0.6117). Age-specific rates had a bimodal increase with peak rates at 70-74 years - 76.7±5.5 (APC=+3.4%, R2=0.2656) and 80-84 years - 78.0±9.1 (APC=+3.7%, R2=0.0875). The age-standardized rate was 13.9 per 100,000 of female population, and the trend has decreased. When compiling thematic maps, mortality rates were determined on the basis of standardized indicators: low - up to 12.5, average - from 12.5 to 15.2, high - above 15.2 per 100,000. The results of the spatial analysis showed the regions with a higher levels of BC mortality rate per 100,000: Pavlodar (16.9), Almaty (19.2) and Astana cities (19.3).

CONCLUSIONS

Age-standardized mortality rates had a strong downward trend (APC=-4.0%, R2=0.9218). The decrease mostly is due to a large coverage of the population by mammography screening and to an improvement in the effectiveness of breast cancer treatment.

The contribution of prognostic factors to socio-demographic inequalities in breast cancer survival in Victoria, Australia

BACKGROUND

Breast cancer survival in Australia varies according to socio-economic status (SES) and between rural and urban places of residence. Part of this disparity may be due to differences in prognostic factors at the time of diagnosis.

METHODS

Women with invasive breast cancer diagnosed from 2008 until 2012 (n = 14,165) were identified from the Victorian Cancer Registry and followed up for 5 years, with death from breast cancer or other causes recorded. A prognostic score, based on stage at diagnosis, cancer grade, whether the cancer was detected via screening, reported comorbidities and age at diagnosis, was constructed for use in a mediation analysis.

RESULTS

Five-year breast cancer mortality for women with breast cancer who were in the lowest quintile of SES (10.3%) was almost double that of those in the highest quintile (5.7%). There was a small survival advantage (1.7% on average, within each socio-economic quintile) of living in inner-regional areas compared with major cities. About half of the socio-economic disparity was mediated by prognostic factors, particularly stage at diagnosis and the presence of comorbidities. The inner-regional survival advantage was not due to differences in prognostic factors.

CONCLUSIONS

Part of the socio-economic disparity in breast cancer survival could be addressed by earlier detection in, and improved general health for, more disadvantaged women. Further research is required to identify additional causes of socio-economic disparities as well as the observed inner-regional survival advantage.

The Promise of Artificial Intelligence in Digestive Healthcare and the Bioethics Challenges It Presents

With modern society well entrenched in the digital area, the use of Artificial Intelligence (AI) to extract useful information from big data has become more commonplace in our daily lives than we perhaps realize. Medical specialties that rely heavily on imaging techniques have become a strong focus for the incorporation of AI tools to aid disease diagnosis and monitoring, yet AI-based tools that can be employed in the clinic are only now beginning to become a reality. However, the potential introduction of these applications raises a number of ethical issues that must be addressed before they can be implemented, among the most important of which are issues related to privacy, data protection, data bias, explainability and responsibility. In this short review, we aim to highlight some of the most important bioethical issues that will have to be addressed if AI solutions are to be successfully incorporated into healthcare protocols, and ideally, before they are put in place. In particular, we contemplate the use of these aids in the field of gastroenterology, focusing particularly on capsule endoscopy and highlighting efforts aimed at resolving the issues associated with their use when available.

Acceptability of Automated Robotic Clinical Breast Examination: Survey Study

BACKGROUND

In the United Kingdom, women aged 50 to 70 years are invited to undergo mammography. However, 10% of invasive breast cancers occur in women aged ≤45 years, representing an unmet need for young women. Identifying a suitable screening modality for this population is challenging; mammography is insufficiently sensitive, whereas alternative diagnostic methods are invasive or costly. Robotic clinical breast examination (R-CBE)-using soft robotic technology and machine learning for fully automated clinical breast examination-is a theoretically promising screening modality with early prototypes under development. Understanding the perspectives of potential users and partnering with patients in the design process from the outset is essential for ensuring the patient-centered design and implementation of this technology.

OBJECTIVE

This study investigated the attitudes and perspectives of women regarding the use of soft robotics and intelligent systems in breast cancer screening. It aimed to determine whether such technology is theoretically acceptable to potential users and identify aspects of the technology and implementation system that are priorities for patients, allowing these to be integrated into technology design.

METHODS

This study used a mixed methods design. We conducted a 30-minute web-based survey with 155 women in the United Kingdom. The survey comprised an overview of the proposed concept followed by 5 open-ended questions and 17 closed questions. Respondents were recruited through a web-based survey linked to the Cancer Research United Kingdom patient involvement opportunities web page and distributed through research networks' mailing lists. Qualitative data generated via the open-ended questions were analyzed using thematic analysis. Quantitative data were analyzed using 2-sample Kolmogorov-Smirnov tests, 1-tailed t tests, and Pearson coefficients.

RESULTS

Most respondents (143/155, 92.3%) indicated that they would definitely or probably use R-CBE, with 82.6% (128/155) willing to be examined for up to 15 minutes. The most popular location for R-CBE was at a primary care setting, whereas the most accepted method for receiving the results was an on-screen display (with an option to print information) immediately after the examination. Thematic analysis of free-text responses identified the following 7 themes: women perceive that R-CBE has the potential to address limitations in current screening services; R-CBE may facilitate increased user choice and autonomy; ethical motivations for supporting R-CBE development; accuracy (and users' perceptions of accuracy) is essential; results management with clear communication is a priority for users; device usability is important; and integration with health services is key.

CONCLUSIONS

There is a high potential for the acceptance of R-CBE in its target user group and a high concordance between user expectations and technological feasibility. Early patient participation in the design process allowed the authors to identify key development priorities for ensuring that this new technology meets the needs of users. Ongoing patient and public involvement at each development stage is essential.

Overdiagnosis Due to Screening Mammography for Breast Cancer among Women Aged 40 Years and Over: A Systematic Review and Meta-Analysis

The current systematic review and meta-analysis was conducted to estimate the incidence of overdiagnosis due to screening mammography for breast cancer among women aged 40 years and older. A PRISMA systematic search appraisal and meta-analysis were conducted. A systematic literature search of English publications in PubMed, Web of Science, EMBASE, Scopus, and Google Scholar was conducted without regard to the region or time period. Generic, methodological, and statistical data were extracted from the eligible studies. A meta-analysis was completed by utilizing comprehensive meta-analysis software. The effect size estimates were calculated using the fail-safe N test. The funnel plot and the Begg and Mazumdar rank correlation tests were employed to find any potential bias among the included articles. The strength of the association between two variables was assessed using Kendall’s tau. Heterogeneity was measured using the I-squared (I2) test. The literature search in the five databases yielded a total of 4214 studies. Of those, 30 articles were included in the final analysis, with sample sizes ranging from 451 to 1,429,890 women. The vast majority of the articles were retrospective cohort designs (24 articles). The age of the recruited women ranged between 40 and 89 years old. The incidence of overdiagnosis due to screening mammography for breast cancer among women aged 40 years and older was 12.6%. There was high heterogeneity among the study articles (I2 = 99.993), and the pooled event rate was 0.126 (95% CI: 15 0.101–0.156). Despite the random-effects meta-analysis showing a high degree of heterogeneity among the articles, the screening tests have to allow for a certain degree of overdiagnosis (12.6%) due to screening mammography for breast cancer among women aged 40 years and older. Furthermore, efforts should be directed toward controlling and minimizing the harmful consequences associated with breast cancer screening.

Test-set training improves the detection rates of invasive cancer in screening mammography

AIM

To investigate if mammographic test-set participation affects routine breast cancer screening performance.

MATERIALS AND METHODS

Clinical audit data between 2008 and 2018 were collected for 35 breast screen readers who participated in the BreastScreen Reader Assessment Strategy (BREAST) and 22 readers with no history of test-set participation. For BREAST readers, the annual audit data were divided according to the year they completed their first test set, and the same years were used randomly to align and divide the data of non-BREAST readers into pre- and post-test set periods. Multiple audit parameters were inspected retrospectively for the two cohorts to identify how their reading performance has evolved in screening mammography.

RESULTS

Investigating 2 calendar years before and after test-set participation, BREAST and non-BREAST readers recalled lower rates of women in the latter period (p=0.03 and p=0.02, respectively). They also improved their positive predictive value (PPV; p=0.01 and p=0.02, respectively). BREAST readers additionally improved their detection rates of invasive cancer (p=0.02) and all cancers (p=0.01). In an extended 3-year comparison, similar improvements occurred in the recall rate for BREAST (p=0.02) and non-BREAST readers (p=0.02) and in PPV (p=0.001, 0.01, respectively); however, improvements in detection rates also occurred exclusively in BREAST readers' performance for invasive cancer (p=0.04), DCIS (p=0.05), and all cancers (p=0.02); however, significant improvements in detection did not involve <15 mm invasive cancers in both periods. Meanwhile, non-BREAST readers demonstrated a decrease in sensitivity (p=0.02).

CONCLUSION

Participation in test sets is linked to over-time improvements in most audit-measured cancer detection rates.

Clinical value of contralateral breast cancers detected by pre-operative MRI in patients diagnosed with DCIS: a population-based cohort study

OBJECTIVES

For patients with ductal carcinoma in situ (DCIS), data about the impact of breast MRI at primary diagnosis on the incidence and characteristics of contralateral breast cancers are scarce.

METHODS

We selected all 8486 women diagnosed with primary DCIS in the Netherlands in 2011-2015 from the Netherlands Cancer Registry. The synchronous and metachronous detection of contralateral DCIS (cDCIS) and contralateral invasive breast cancer (cIBC) was assessed for patients who received an MRI upon diagnosis (MRI group) and for an age-matched control group without MRI.

RESULTS

Nineteen percent of patients received an MRI, of which 0.8% was diagnosed with synchronous cDCIS and 1.3% with synchronous cIBC not found by mammography. The 5-year cumulative incidence of synchronous plus metachronous cDCIS was higher for the MRI versus age-matched control group (2.0% versus 0.9%, p = 0.02) and similar for cIBC (3.5% versus 2.3%, p = 0.17). The increased incidence of cDCIS was observed in patients aged < 50 years (sHR = 4.22, 95% CI: 1.19-14.99), but not in patients aged 50-74 years (sHR = 0.89, 95% CI: 0.41-1.93).

CONCLUSIONS

MRI at primary DCIS diagnosis detected additional synchronous cDCIS and cIBC, and was associated with a higher rate of metachronous cDCIS without decreasing the rate of metachronous cIBC. This finding was most evident in younger patients.

KEY POINTS

• Magnetic resonance imaging at primary diagnosis of ductal carcinoma in situ detected an additional synchronous breast lesion in 2.1% of patients. • In patients aged younger than 50 years, the use of pre-operative MRI was associated with a fourfold increase in the incidence of a second contralateral DCIS without decreasing the incidence of metachronous invasive breast cancers up to 5 years after diagnosis. • In patients aged over 50 years, the use of pre-operative MRI did not result in a difference in the incidence of a second contralateral DCIS or metachronous invasive breast cancer.

Considerations for Evaluating the Introduction of New Cancer Screening Technology: Use of Interval Cancers to Assess Potential Benefits and Harms

This framework focuses on the importance of the consideration of the downstream intermediate and long-term health outcomes when a change to a screening program is introduced. The authors present a methodology for utilising the relationship between screen-detected and interval cancer rates to infer the benefits and harms associated with a change to the program. A review of the previous use of these measures in the literature is presented. The framework presents other aspects to consider when utilizing this methodology, and builds upon an existing framework that helps researchers, clinicians, and policy makers to consider the impacts of changes to screening programs on health outcomes. It is hoped that this research will inform future evaluative studies to assess the benefits and harms of changes to screening programs.

Women's preference to apply shared decision-making in breast cancer screening: a discrete choice experiment

OBJECTIVE

To analyse women's stated preferences for establishing the relative importance of each attribute of shared decision-making (SDM) and their willingness to pay (WTP) for more participatory care in breast cancer screening programmes (BCSP).

DESIGN

A discrete choice experiment was designed with 12 questions (choice tasks). It included three attributes: 'How the information is obtained', regarding benefits and harms; whether there is a 'Dialogue for scheduled mammography' between the healthcare professional and the woman; and, 'Who makes the decision', regarding participation in BCSP. Data were obtained using a survey that included 12 choice tasks, 1 question on WTP and 7 socioeconomic-related questions. The analysis was performed using conditional mixed-effect logit regression and stratification according to WTP.

SETTING

Data collection related to BCSP was conducted between June and November 2021 in Catalonia, Spain.

PARTICIPANTS

Sixty-five women aged between 50 and 60.

MAIN OUTCOME MEASURES

Women's perceived utility of each attribute, trade-off on these attributes and WTP for SDM in BCSP.

RESULT

The only significant attribute was 'Who makes the decision'. The decision made alone (coefficient=2.879; 95% CI=2.297 to 3.461) and the decision made together with a healthcare professional (2.375; 95% CI=1.573 to 3.177) were the options preferred by women. The former contributes 21% more utility than the latter. Moreover, 52.3% of the women stated a WTP of €10 or more for SDM. Women's preferences regarding attributes did not influence their WTP.

CONCLUSIONS

The participant women refused a current paternalistic model and preferred either SDM or informed decision-making in BCSP.

Knowledge and Factors Associated with Breast Cancer Self-Screening Intention among Saudi Female College Students: Utilization of the Health Belief Model

Breast cancer (BC) screening is vital, as it is linked to a greater likelihood of survival, more effective treatment, and better quality of life. One of the most extensively applied models for conceptualizing probable barriers and facilitators to the adoption of desired health behavior is the health belief model (HBM). This study aimed to assess the impact of health perception and knowledge on breast self-examination intention (BSE) using HBM. HBM measures specific factors (perceived susceptibility, severity, barriers, benefits, cues to action, and self-efficacy) that impact one's intention to use BSE. Data were collected from female undergraduate students (n = 680) using a cross-sectional design, stratified simple random sampling, and a self-administered structured online questionnaire. We used multivariable logistic regression to evaluate our assumptions for students who intended to self-examine for BC. For demographic factors, we modified the multivariate model. Most respondents (93%) were under the age of 24 years. Female students from health colleges (48.5%), in their fourth academic year (42.6%), and from the southern region (57.6%) accounted for the majority of the sample. Respondents with a family history of BC were 9.7% of the total. Categories for age, college, region, residency, and BSE intention showed significant differences in their average knowledge scores. The survey revealed that 72.4% were aware of abnormal breast changes. Three constructs of the health belief model (perceived benefit, perceived barriers, and self-efficacy) are good predictors of BSE intention. Theory-based behavioral change interventions are urgently required for students to improve their prevention practices. Furthermore, these interventions will be effective if they are designed to remove barriers to BSE intention, improve female students' self-efficacy, and enlighten them on the benefits of self-examination.

Breast surgery: a narrative review

Breast cancer is the commonest human cancer globally and one in seven Australian women will develop it in their lifetime.

Surgery is the mainstay of management both for women who are at high risk of breast cancer and for those who have been diagnosed.

Increased understanding of how to predict who is most at risk of breast cancer is leading to the possibility of risk‐based screening, allowing better and more targeted early detection for women at high risk, and contrast imaging techniques are proving more accurate in diagnosing and staging cancer.

The evolution of surgical practice includes the widespread use of oncoplastic surgery, allowing better cosmetic and oncological outcomes; reconstructive surgical advances, using free flap techniques; and sequencing of systemic and local therapies to better tailor treatments to the patient’s cancer and improve outcomes.

Recognition of side effects of breast cancer treatment have led to improvement in the management of conditions such as chronic pain and lymphoedema, as well as addressing the psychosocial, body image and sexual complications caused by the cancer and its treatment.

Breast Cancer in Asia: Incidence, Mortality, Early Detection, Mammography Programs, and Risk-Based Screening Initiatives

Simple Summary

Nearly all breast cancer patients survive for more than five years when the tumor is found early and in the localized stage. Regular clinical breast examinations, mammograms, and monthly self-exams of the breasts all contribute to early detection. However, late-stage breast cancers are common in many Asian countries. Low-income countries suffer from a lack of resources for breast cancer screening. High-income countries, on the other hand, are not benefiting fully from national breast screening programs due to an underutilization of the preventive healthcare services available. Existing reviews on Asian breast cancers are heavily focused on risk factors. The question of whether we should adopt or adapt the knowledge generated from non-Asian breast cancers would benefit from an extension into screening guidelines. In addition, several Asian countries are piloting studies that move away from the age-based screening paradigm.

Abstract

Close to half (45.4%) of the 2.3 million breast cancers (BC) diagnosed in 2020 were from Asia. While the burden of breast cancer has been examined at the level of broad geographic regions, literature on more in-depth coverage of the individual countries and subregions of the Asian continent is lacking. This narrative review examines the breast cancer burden in 47 Asian countries. Breast cancer screening guidelines and risk-based screening initiatives are discussed.

Global Increase in Breast Cancer Incidence: Risk Factors and Preventive Measures

Breast cancer is a global cause for concern owing to its high incidence around the world. The alarming increase in breast cancer cases emphasizes the management of disease at multiple levels. The management should start from the beginning that includes stringent cancer screening or cancer registry to effective diagnostic and treatment strategies. Breast cancer is highly heterogeneous at morphology as well as molecular levels and needs different therapeutic regimens based on the molecular subtype. Breast cancer patients with respective subtype have different clinical outcome prognoses. Breast cancer heterogeneity emphasizes the advanced molecular testing that will help on-time diagnosis and improved survival. Emerging fields such as liquid biopsy and artificial intelligence would help to under the complexity of breast cancer disease and decide the therapeutic regimen that helps in breast cancer management. In this review, we have discussed various risk factors and advanced technology available for breast cancer diagnosis to combat the worst breast cancer status and areas that need to be focused for the better management of breast cancer.

Microwave 3D Imaging System Featuring the Phase Coherence Factor for Improved Beamforming

BACKGROUND

This paper presents an improved radar-based imaging system for breast cancer detection that features p-slot ultrawideband antennae in a 32-array set-up. The improved reconstruction algorithm incorporates the phase coherence factor (PCF) into the conventional delay and sum (DAS) beamforming algorithm, thus effectively suppressing noise arising from side- and grating-lobe interferences.

METHODS

The system is tested by using several breast models fabricated from chemical mixtures formulated on the basis of realistic human tissues. Each model is placed in a hemispherical breast radome that was fabricated from polylactide material and surrounded by 32 p-slot antennae mounted in four concentric layers. These antennae are connected to an 8.5 GHz vector network analyser through two 16-channel multiplexers that automatically switch different combinations of transmitter and receiver pairs in a sequential manner.

RESULTS

The system can accurately detect 5 mm tumours in a complex and homogeneously dense 3D breast model with an average signal-to-clutter ratio and full-width half-maximum of 7.0 dB and 2.3 mm, respectively. These values are more competitive than the values of other beamforming algorithms even with contrasts of as low as 1:2.

CONCLUSION

The proposed PCF-weighted DAS is the best-performing algorithm amongst the tested beamforming techniques. This research paves the way for a clinical trial involving human subjects. Our laboratory is planning such a trial as part of future work.

Classification of Breast Cancer in Mammograms with Deep Learning Adding a Fifth Class

Breast cancer is one of the diseases of most profound concern, with the most prevalence worldwide, where early detections and diagnoses play the leading role against this disease achieved through imaging techniques such as mammography. Radiologists tend to have a high false positive rate for mammography diagnoses and an accuracy of around 82%. Currently, deep learning (DL) techniques have shown promising results in the early detection of breast cancer by generating computer-aided diagnosis (CAD) systems implementing convolutional neural networks (CNNs). This work focuses on applying, evaluating, and comparing the architectures: AlexNet, GoogLeNet, Resnet50, and Vgg19 to classify breast lesions after using transfer learning with fine-tuning and training the CNN with regions extracted from the MIAS and INbreast databases. We analyzed 14 classifiers, involving 4 classes as several researches have done it before, corresponding to benign and malignant microcalcifications and masses, and as our main contribution, we also added a 5th class for the normal tissue of the mammary parenchyma increasing the correct detection; in order to evaluate the architectures with a statistical analysis based on the received operational characteristics (ROC), the area under the curve (AUC), F1 Score, accuracy, precision, sensitivity, and specificity. We generate the best results with the CNN GoogLeNet trained with five classes on a balanced database with an AUC of 99.29%, F1 Score of 91.92%, the accuracy of 91.92%, precision of 92.15%, sensitivity of 91.70%, and specificity of 97.66%, concluding that GoogLeNet is optimal as a classifier in a CAD system to deal with breast cancer.

Multi-Omic Approaches to Breast Cancer Metabolic Phenotyping: Applications in Diagnosis, Prognosis, and the Development of Novel Treatments

Breast cancer (BC) is characterized by high disease heterogeneity and represents the most frequently diagnosed cancer among women worldwide. Complex and subtype-specific gene expression alterations participate in disease development and progression, with BC cells known to rewire their cellular metabolism to survive, proliferate, and invade. Hence, as an emerging cancer hallmark, metabolic reprogramming holds great promise for cancer diagnosis, prognosis, and treatment. Multi-omics approaches (the combined analysis of various types of omics data) offer opportunities to advance our understanding of the molecular changes underlying metabolic rewiring in complex diseases such as BC. Recent studies focusing on the combined analysis of genomics, epigenomics, transcriptomics, proteomics, and/or metabolomics in different BC subtypes have provided novel insights into the specificities of metabolic rewiring and the vulnerabilities that may guide therapeutic development and improve patient outcomes. This review summarizes the findings of multi-omics studies focused on the characterization of the specific metabolic phenotypes of BC and discusses how they may improve clinical BC diagnosis, subtyping, and treatment.

Tumor-associated lymphocytes and macrophages are related to stromal elastosis and vascular invasion in breast cancer

The tumor microenvironment plays a critical role in breast cancer progression. Here, we investigated tumor-infiltrating lymphocytes (TILs) and associations with macrophage numbers, tumor stromal elastosis, vascular invasion, and tumor detection mode. We performed a population-based retrospective study using data from The Norwegian Breast Cancer Screening Program in Vestfold County (2004-2009), including 200 screen-detected and 82 interval cancers. The number of TILs (CD45+, CD3+, CD4+, CD8+, and FOXP3+) and tumor-associated macrophages (CD163+) was counted using immunohistochemistry on tissue microarray slides. Lymphatic and blood vessel invasion (LVI and BVI) were recorded using D2-40 and CD31 staining, and the amount of elastosis (high/low) was determined on regular HE-stained slides. High numbers of all TIL subsets were associated with LVI (p ≤ 0.04 for all), and high counts of several TIL subgroups (CD8+, CD45+, and FOXP3+) were associated with BVI (p ≤ 0.04 for all). Increased levels of all TIL subsets, except CD4+, were associated with estrogen receptor-negative tumors (p < 0.001) and high tumor cell proliferation by Ki67 (p < 0.001). Furthermore, high levels of all TIL subsets were associated with high macrophage counts (p < 0.001) and low-grade stromal elastosis (p ≤ 0.02). High counts of CD3+, CD8+, and FOXP3+ TILs were associated with interval detected tumors (p ≤ 0.04 for all). Finally, in the luminal A subgroup, high levels of CD3+ and FOXP3+ TILs were associated with shorter recurrence-free survival, and high counts of FOXP3+ were linked to reduced breast cancer-specific survival. In conclusion, higher levels of different TIL subsets were associated with stromal features such as high macrophage counts (CD163+), presence of vascular invasion, absence of stromal elastosis, as well as increased tumor cell proliferation and interval detection mode. Our findings support a link between immune cells and vascular invasion in more aggressive breast cancer. Notably, presence of TIL subsets showed prognostic value within the luminal A category.

Healthcare professionals' behaviour regarding the implementation of shared decision-making in screening programmes: A systematic review

OBJECTIVE

To explore the barriers to and facilitators of healthcare professionals' implementation of SDM regarding screening programmes.

METHOD

A systematic review was conducted in PubMed, Cochrane Library, CINHAL, and PsyscInfo. The barriers and facilitators identified were classified into three factors based on their origin: patients, healthcare system performance, and healthcare professionals themselves.

RESULTS

Eight studies were selected: seven related to cancer screening. The most significant facilitators were literacy and interest in active participation, both of which have their origins in patients. The most significant barriers identified for the first time in a systematic review were legal conflict, lack of remuneration and lack of flexibility in clinical guidelines in screening programmes.

CONCLUSION

The results of this study show that there are differences between barriers and facilitators for SDM when it is applied in the context of healthy people who perform preventive activities, particularly screening, in contrast to general medical consultation contexts.

PRACTICAL IMPLICATIONS

The authors suggest that to advance in the practice of SDM, we need to develop and disseminate training documents. Further, SDM should be incorporated into clinical guidelines. There should be more studies focusing on healthcare professionals' behaviour within the context of the uncertainty of screening programmes.

Assessment of surveillance versus etiologic factors in the reciprocal association between papillary thyroid cancer and breast cancer

BACKGROUND

Mutually increased risks for thyroid and breast cancer have been reported, but the contribution of etiologic factors versus increased medical surveillance to these associations is unknown.

METHODS

Leveraging large-scale US population-based cancer registry data, we used standardized incidence ratios (SIRs) to investigate the reciprocal risks of thyroid and breast cancers among adult females diagnosed with a first primary invasive, non-metastatic breast cancer (N = 652,627) or papillary thyroid cancer (PTC) (N = 92,318) during 2000-2017 who survived ≥1-year.

RESULTS

PTC risk was increased 1.3-fold [N = 1434; SIR = 1.32; 95 % confidence interval (CI) = 1.25-1.39] after breast cancer compared to the general population. PTC risk declined significantly with time since breast cancer (Poisson regression = P_trend <0.001) and was evident only for tumors ≤2 cm in size. The SIRs for PTC were higher after hormone-receptor (HR)+ (versus HR-) and stage II or III (versus stage 0-I) breast tumors. Breast cancer risk was increased 1.2-fold (N = 2038; SIR = 1.21; CI = 1.16-1.26) after PTC and was constant over time since PTC but was only increased for stage 0-II and HR + breast cancers.

CONCLUSION

Although some of the patterns by latency, stage and size are consistent with heightened surveillance contributing to the breast-thyroid association, we cannot exclude a role of shared etiology or treatment effects.

Cost-effectiveness evaluation of mammography screening program in Taiwan: Adjusting different distributions of age and calendar year for real world data

BACKGROUND/PURPOSE

We estimated loss-of-life expectancy (LE) and lifetime medical expenditures (LME) stratified by stages to evaluate the cost-effectiveness of breast cancer (BC) screening in Taiwan.

METHODS

We interlinked four national databases- Cancer Registry, Mortality Registry, National Health Insurance Claim, and Mammography Screening. A cohort of 123,221 BC was identified during 2002-2015 and followed until December 31, 2017. We estimated LE and loss-of-LE by rolling extrapolation algorithm using age-, sex-, and calendar-year-matched referents simulated from vital statistics. LME was estimated by multiplying monthly cost with survival probability and adjusted for annual discount rate. We calculated incremental cost-effectiveness ratio (ICER) by comparing the loss-of-LE of those detected by screening versus non-screening after accounting for administration fees and radiation-related excess BC.

RESULTS

The LEs of stages I, II, III, and IV were 31.4, 27.2, 20.0, and 5.2 years, respectively, while the loss-of-LEs were 1.2, 4.9, 11.7, and 25.0 years with corresponding LMEs of US$ 73,791, 79,496, 89,962, and 66,981, respectively. The difference in LE between stages I and IV was 26.2 years while that of loss-of-LE was 23.8 years, which implies that a potential lead time bias may exist if diagnosis at younger ages for earlier stages were not adjusted for. The ICER of mammography seemed cost-saving after the coverage exceeded half a million.

CONCLUSION

Mammography could detect BC early and be cost-saving after adjustment for different distributions of age and calendar year of diagnosis. Future studies exploring healthcare expenditure and impaired quality of life for false-positive cases are warranted.

Impact of Full-Field Digital Mammography Versus Film-Screen Mammography in Population Screening: A Meta-Analysis

BACKGROUND

Breast screening programs replaced film mammography with digital mammography, and the effects of this practice shift in population screening on health outcomes can be measured through examination of cancer detection and interval cancer rates.

METHODS

A systematic review and random effects meta-analysis were undertaken. Seven databases were searched for publications that compared film with digital mammography within the same population of asymptomatic women and reported cancer detection and/or interval cancer rates.

RESULTS

The analysis included 24 studies with 16 583 743 screening examinations (10 968 843 film and 5 614 900 digital). The pooled difference in the cancer detection rate showed an increase of 0.51 per 1000 screens (95% confidence interval [CI] = 0.19 to 0.83), greater relative increase for ductal carcinoma in situ (25.2%, 95% CI = 17.4% to 33.5%) than invasive (4%, 95% CI = -3% to 13%), and a recall rate increase of 6.95 (95% CI = 3.47 to 10.42) per 1000 screens after the transition from film to digital mammography. Seven studies (80.8% of screens) reported interval cancers: the pooled difference showed no change in the interval cancer rate with -0.02 per 1000 screens (95% CI = -0.06 to 0.03). Restricting analysis to studies at low risk of bias resulted in findings consistent with the overall pooled results for all outcomes.

CONCLUSIONS

The increase in cancer detection following the practice shift to digital mammography did not translate into a reduction in the interval cancer rate. Recall rates were increased. These results suggest the transition from film to digital mammography did not result in health benefits for screened women. This analysis reinforces the need to carefully evaluate effects of future changes in technology, such as tomosynthesis, to ensure new technology leads to improved health outcomes and beyond technical gains.

A Review of Breast Imaging for Timely Diagnosis of Disease

Breast cancer (BC) is the cancer with the highest incidence in women in the world. In this last period, the COVID-19 pandemic has caused in many cases a drastic reduction of routine breast imaging activity due to the combination of various factors. The survival of BC is directly proportional to the earliness of diagnosis, and especially during this period, it is at least fundamental to remember that a diagnostic delay of even just three months could affect BC outcomes. In this article we will review the state of the art of breast imaging, starting from morphological imaging, i.e., mammography, tomosynthesis, ultrasound and magnetic resonance imaging and contrast-enhanced mammography, and their most recent evolutions; and ending with functional images, i.e., magnetic resonance imaging and contrast enhanced mammography.

The politicians' perspectives on participation in mammographic screening: an interview-based study from a region in Sweden

Background

Breast cancer is the most common cancer type among women globally. To facilitate early detection, all 40–74-year-old female residents of Sweden are invited to participate in a population-based mammographic screening programme. Approximately 20% of all invited women decline the offer, and if this is due to systematic differences that can be adjusted, it can indicate inequity in healthcare. Assessment of and being updated about the health and healthcare of the residents are largely the responsibilities of the self-governed regions in Sweden. The understanding of the residents’ health serves as a basis for decision making and priority setting. This study aims to describe how politicians representing a region in Sweden perceive women’s participation in mammographic screening and the politicians’ own possibility to promote such participation.

Methods

Qualitative thematic analysis was conducted on the data obtained from individual semi-structured interviews held in 2019. The interviewees comprised ten politicians (six women and four men, 38–71 years old) representing a sub-committee focusing on public health and healthcare issues.

Results

Two main themes have been identified: 1) expected actions and 2) expected conditions for acting, including a total of four sub-themes. According to the politicians, the expected actions, such as obtaining information and being updated about matters regarding mammographic screening, concern both the women invited to the screening and the politicians themselves. Additionally, for both the individual and the healthcare organisation, here represented by the politicians, expected actions entail a shared commitment to maintain health. The expected conditions for acting refer to the politician’s awareness of the factors influencing the women’s decision to undergo or refuse the screening and having the resources to enable taking actions to facilitate participation.

Conclusions

Expected actions and expected conditions for acting are tightly connected and entail some form of prioritisation by the politicians. Setting the priorities can be based on information about the purpose of the screening and an understanding of social determinants’ impacts on women’s decision to refrain from mammographic screening, as well as available resources.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13690-021-00576-6.

Identifying normal mammograms in a large screening population using artificial intelligence

OBJECTIVES

To evaluate the potential of artificial intelligence (AI) to identify normal mammograms in a screening population.

METHODS

In this retrospective study, 9581 double-read mammography screening exams including 68 screen-detected cancers and 187 false positives, a subcohort of the prospective population-based Malmö Breast Tomosynthesis Screening Trial, were analysed with a deep learning-based AI system. The AI system categorises mammograms with a cancer risk score increasing from 1 to 10. The effect on cancer detection and false positives of excluding mammograms below different AI risk thresholds from reading by radiologists was investigated. A panel of three breast radiologists assessed the radiographic appearance, type, and visibility of screen-detected cancers assigned low-risk scores (≤ 5). The reduction of normal exams, cancers, and false positives for the different thresholds was presented with 95% confidence intervals (CI).

RESULTS

If mammograms scored 1 and 2 were excluded from screen-reading, 1829 (19.1%; 95% CI 18.3-19.9) exams could be removed, including 10 (5.3%; 95% CI 2.1-8.6) false positives but no cancers. In total, 5082 (53.0%; 95% CI 52.0-54.0) exams, including 7 (10.3%; 95% CI 3.1-17.5) cancers and 52 (27.8%; 95% CI 21.4-34.2) false positives, had low-risk scores. All, except one, of the seven screen-detected cancers with low-risk scores were judged to be clearly visible.

CONCLUSIONS

The evaluated AI system can correctly identify a proportion of a screening population as cancer-free and also reduce false positives. Thus, AI has the potential to improve mammography screening efficiency.

KEY POINTS

• Retrospective study showed that AI can identify a proportion of mammograms as normal in a screening population. • Excluding normal exams from screening using AI can reduce false positives.

What can be done to encourage women from Black, Asian and minority ethnic backgrounds to attend breast screening? A qualitative synthesis of barriers and facilitators

OBJECTIVE

The objective of the study is to identify the barriers to UK Black, Asian and Minority Ethnic (BAME) women attending breast screening and subsequently, support the growing evidence base providing solutions to the public health problem of ethnic variation within screening attendance.

STUDY DESIGN

A systematic review and thematic analysis of UK-based, qualitative studies concerning BAME women.

METHODS

The methodology of this review is based on Cochrane guidelines. A search strategy was applied to Embase, PubMed and Medline. Predefined inclusion and exclusion criteria yielded 8 final articles which were appraised and thematically analysed.

RESULTS

The main findings of the review revealed three overarching themes: knowledge-related, access-related and cultural-related factors. The emphasis of the importance of knowledge was highlighted by all studies identifying a lack of knowledge as a key barrier to screening attendance.

CONCLUSIONS

BAME women have disproportionally lower breast screening attendance and a lack of knowledge is an essential barrier to overcome when addressing this health inequality.

Magnetic Resonance Imaging in Screening of Breast Cancer

Magnetic Resonance (MR) imaging is the most sensitive modality for breast cancer detection but is currently limited to screening women at high risk due to limited specificity and test accessibility. However, specificity of MR imaging improves with successive rounds of screening, and abbreviated approaches have the potential to increase access and decrease cost. There is growing evidence to support supplemental MR imaging in moderate-risk women, and current guidelines continue to evolve. Functional imaging has the potential to maximize survival benefit of screening. Leveraging MR imaging as a possible primary screening tool is therefore also being investigated in average-risk women.

A pragmatic approach to tackle the rising burden of breast cancer through prevention & early detection in countries 'in transition'

Among the emerging economies Brazil, Russia, India, China and South Africa (together known as the BRICS countries) share collectively approximately 40 per cent of the global population and contribute to 25 per cent of the world gross domestic products. All these countries are facing the formidable challenge of rising incidence of breast cancer and significant number of premature deaths from the disease. A multidimensional approach involving prevention, early detection and improved treatment is required to counteract the growing burden of breast cancer. A growing trend in the prevalence of major preventable risk factors of breast cancer such as obesity, western dietary habits, lack of physical activity, consumption of alcohol and smoking is contributing significantly to the rising burden of the disease in BRICS nations. Specific interventions are needed at the individual and population levels to mitigate these risk factors, preferably within the broader framework of non-communicable disease control programme. Population-based quality assured mammography-based screening of the 50-69 yr old women can reduce breast cancer mortality at least by 20 per cent. However, none of the BRICS countries have been able to implement population-based organized screening programme. Large scale opportunistic screening with mammography targeting predominantly the younger women is causing harms to the women and wasting precious healthcare resources. There are recent national recommendations to screen women with mammography in Brazil and Russia and with clinical breast examination in China (along with ultrasound) and India. Given the challenges of implementing systematic screening of the population, the BRICS countries should prioritize the early diagnosis approach and invest in educating the women about the breast cancer symptoms, training the frontline health providers to clinically detect breast cancers and appropriately refer for diagnostic confirmation, and creating improved access to good quality diagnostic and treatment facilities for breast cancer. The early diagnosis approach has been proved to achieve downstaging and improve survival at a fraction of the resources needed for population screening. The countries also need to focus on improving the services and capacity for multidisciplinary treatment of breast cancer, histopathology and immunohistochemistry, safe administration of chemotherapy and palliative care.

Overview of Breast Cancer and Implications of Overtreatment of Early-Stage Breast Cancer: An Indian Perspective

The prevalence and mortality of breast cancer is increasing in Asian countries, including India. With advances in medical technology leading to better detection and characterization of the disease, it has been possible to classify breast cancer into various subtypes using markers, which helps predict the risk of distant recurrence, response to therapy, and prognosis using a combination of molecular and clinical parameters. Breast cancer and its therapy, mainly surgery, systemic therapy (anticancer chemotherapy, hormonal therapy, targeted therapy, and immunotherapy), and radiation therapy, are associated with significant adverse influences on physical and mental health, quality of life, and the economic status of the patient and her family. The fear of recurrence and its devastating effects often leads to overtreatment, with a toxic cost to the patient financially and physically in cases in which this is not required. This article discusses some aspects of a breast cancer diagnosis and its impact on the various facets of the life of the patient and her family. It further elucidates the role of prognostic factors, the currently available biomarkers and prognostic signatures, and the importance of ethnically validating biomarkers and prognostic signatures.

[Preoperative breast imaging review: Interests and limits of specialized validation in oncology]

OBJECTIVES

To evaluate the impact of systematic radiological review by breast specialist radiologist of malignant breast lesion imaging on the therapeutic management of patients.

MATERIALS AND METHODS

Data collection was performed for patients with histopathologically proved breast cancer or suspicious breast lesion on imaging realized out of our institution. Patients underwent systematic mammary and axillary ultrasound, imaging review and if necessary complementary mammographic images. We analyzed the number of additional breast biopsies and axillary lymph node fine needle aspiration (FNA) with their histopathological results. We assessed their impact by comparing the final surgical treatment to the one planned before review.

RESULTS

Two hundred and seventeen patients were included, with a total of 230 BIRADS 0, 4, 5 or 6 breast lesions. Seventy-six additional breast core biopsies were realized, leading to diagnose 43 additional BIRADS 6 lesions (24 infiltrative carcinomas, 9 DCIS and 10 atypical lesions) in 30 patients (13.82%). Thirty-five additional lymph node FNA were realized with 12 metastatic nodes and 3 false negative samples. Imaging review lead to change surgical treatment in 59 patients (27.19%, P<0.01) with modification in breast surgery in 37 patients, axillary surgery in 8 patients and both sites surgery in 12 patients.

CONCLUSION

This study shows an impact of systematic radiological review by breast specialist radiologist in therapeutic management of patients treated for malignant breast lesion.

DNA methylation landscape of triple-negative ductal carcinoma in situ (DCIS) progressing to the invasive stage in canine breast cancer

Triple-negative breast cancer (TNBC) is a subtype of breast cancer unresponsive to traditional receptor-targeted treatments, leading to a disproportionate number of deaths. Invasive breast cancer is believed to evolve from non-invasive ductal carcinoma in situ (DCIS). Detection of triple-negative DCIS (TN-DCIS) is challenging, therefore strategies to study molecular events governing progression of pre-invasive TN-DCIS to invasive TNBC are needed. Here, we study a canine TN-DCIS progression and investigate the DNA methylation landscape of normal breast tissue, atypical ductal hyperplasia (ADH), DCIS and invasive breast cancer. We report hypo- and hypermethylation of genes within functional categories related to cancer such as transcriptional regulation, apoptosis, signal transduction, and cell migration. DNA methylation changes associated with cancer-related genes become more pronounced at invasive breast cancer stage. Importantly, we identify invasive-only and DCIS-specific DNA methylation alterations that could potentially determine which lesions progress to invasive cancer and which could remain as pre-invasive DCIS. Changes in DNA methylation during TN-DCIS progression in this canine model correspond with gene expression patterns in human breast tissues. This study provides evidence for utilizing methylation status of gene candidates to define late-stage (DCIS and invasive), invasive stage only or DCIS stage only of TN-DCIS progression.

Perspectives on the Overdiagnosis of Breast Cancer Associated with Mammographic Screening

Overdiagnosis of breast cancer refers to the screen detection and diagnosis of breast cancer that would not have progressed to symptomatic cancer during a woman's lifetime. Screening mammography, like all screening tests, will result in some overdiagnosis that is attributable to competing causes of death occurring during the lead time (the time period between asymptomatic screen detection and clinical detection) and detection of very indolent cancer. The primary harm of overdiagnosis relates to subsequent (unnecessary) treatment. Importantly, overdiagnosis concerns must be balanced with the lifesaving and morbidity benefits of screening mammography and the prevention of some invasive cancer by detection and treatment of ductal carcinoma in situ. Reasonable estimates of overdiagnosis of women aged 40-80 years are in the order of 1%-10%, with lower values when overdiagnosis is restricted to invasive cancer and among younger women. Prospective identification of an overdiagnosed invasive cancer is not currently possible. Delaying screening until age 50 years or screening biennially rather than annually will not substantially reduce the amount of overdiagnosis of invasive cancer. The clinical significance of overdiagnosis will continue to be minimized as advances in personalized medicine further reduce treatment-associated morbidity.

The ethical, legal and social implications of using artificial intelligence systems in breast cancer care

Breast cancer care is a leading area for development of artificial intelligence (AI), with applications including screening and diagnosis, risk calculation, prognostication and clinical decision-support, management planning, and precision medicine. We review the ethical, legal and social implications of these developments. We consider the values encoded in algorithms, the need to evaluate outcomes, and issues of bias and transferability, data ownership, confidentiality and consent, and legal, moral and professional responsibility. We consider potential effects for patients, including on trust in healthcare, and provide some social science explanations for the apparent rush to implement AI solutions. We conclude by anticipating future directions for AI in breast cancer care. Stakeholders in healthcare AI should acknowledge that their enterprise is an ethical, legal and social challenge, not just a technical challenge. Taking these challenges seriously will require broad engagement, imposition of conditions on implementation, and pre-emptive systems of oversight to ensure that development does not run ahead of evaluation and deliberation. Once artificial intelligence becomes institutionalised, it may be difficult to reverse: a proactive role for government, regulators and professional groups will help ensure introduction in robust research contexts, and the development of a sound evidence base regarding real-world effectiveness. Detailed public discussion is required to consider what kind of AI is acceptable rather than simply accepting what is offered, thus optimising outcomes for health systems, professionals, society and those receiving care.

Breast cancer

Breast cancer is the most frequent malignancy in women worldwide and is curable in ~70-80% of patients with early-stage, non-metastatic disease. Advanced breast cancer with distant organ metastases is considered incurable with currently available therapies. On the molecular level, breast cancer is a heterogeneous disease; molecular features include activation of human epidermal growth factor receptor 2 (HER2, encoded by ERBB2), activation of hormone receptors (oestrogen receptor and progesterone receptor) and/or BRCA mutations. Treatment strategies differ according to molecular subtype. Management of breast cancer is multidisciplinary; it includes locoregional (surgery and radiation therapy) and systemic therapy approaches. Systemic therapies include endocrine therapy for hormone receptor-positive disease, chemotherapy, anti-HER2 therapy for HER2-positive disease, bone stabilizing agents, poly(ADP-ribose) polymerase inhibitors for BRCA mutation carriers and, quite recently, immunotherapy. Future therapeutic concepts in breast cancer aim at individualization of therapy as well as at treatment de-escalation and escalation based on tumour biology and early therapy response. Next to further treatment innovations, equal worldwide access to therapeutic advances remains the global challenge in breast cancer care for the future.

Proteomic profiling of extracellular vesicles allows for human breast cancer subtyping

Extracellular vesicles (EVs) are a potential source of disease-associated biomarkers for diagnosis. In breast cancer, comprehensive analyses of EVs could yield robust and reliable subtype-specific biomarkers that are still critically needed to improve diagnostic routines and clinical outcome. Here, we show that proteome profiles of EVs secreted by different breast cancer cell lines are highly indicative of their respective molecular subtypes, even more so than the proteome changes within the cancer cells. Moreover, we detected molecular evidence for subtype-specific biological processes and molecular pathways, hyperphosphorylated receptors and kinases in connection with the disease, and compiled a set of protein signatures that closely reflect the associated clinical pathophysiology. These unique features revealed in our work, replicated in clinical material, collectively demonstrate the potential of secreted EVs to differentiate between breast cancer subtypes and show the prospect of their use as non-invasive liquid biopsies for diagnosis and management of breast cancer patients.

Digital Breast Tomosynthesis: Concepts and Clinical Practice

Digital breast tomosynthesis (DBT) is emerging as the standard of care for breast imaging based on improvements in both screening and diagnostic imaging outcomes. The additional information obtained from the tomosynthesis acquisition decreases the confounding effect of overlapping tissue, allowing for improved lesion detection, characterization, and localization. In addition, the quasi three-dimensional information obtained from the reconstructed DBT data set allows a more efficient imaging work-up than imaging with two-dimensional full-field digital mammography alone. Herein, the authors review the benefits of DBT imaging in screening and diagnostic breast imaging.

Life and death of circulating cell-free DNA

Tumor-specific, circulating cell-free DNA in liquid biopsies is a promising source of biomarkers for minimally invasive serial monitoring of treatment responses in cancer management. We will review the current understanding of the origin of circulating cell-free DNA and different forms of DNA release (including various types of cell death and active secretion processes) and clearance routes. The dynamics of extracellular DNA in blood during therapy and the role of circulating DNA in pathophysiological processes (tumor-associated inflammation, NETosis, and pre-metastatic niche development) provide insights into the mechanisms that contribute to tumor development and metastases formation. Better knowledge of circulating tumor-specific cell-free DNA could facilitate the development of new therapeutic and diagnostic options for cancer management.

Barriers to Breast Cancer Screening among Diverse Cultural Groups in Melbourne, Australia

This study explored the association between health literacy, barriers to breast cancer screening, and breast screening participation for women from culturally and linguistically diverse (CALD) backgrounds. English-, Arabic- and Italian-speaking women (n = 317) between the ages of 50 to 74 in North West Melbourne, Australia were recruited to complete a survey exploring health literacy, barriers to breast cancer screening, and self-reported screening participation. A total of 219 women (69%) reported having a breast screen within the past two years. Results revealed that health literacy was not associated with screening participation. Instead, emotional barriers were a significant factor in the self-reported uptake of screening. Three health literacy domains were related to lower emotional breast screening barriers, feeling understood and supported by healthcare providers, social support for health and understanding health information well enough to know what to do. Compared with English- and Italian-speaking women, Arabic-speaking women reported more emotional barriers to screening and greater challenges in understanding health information well enough to know what to do. Interventions that can improve breast screening participation rates should aim to reduce emotional barriers to breast screening, particularly for Arabic-speaking women.

Online information about risks and benefits of screening mammography in 10 European countries: An observational Web sites analysis

Most publications about breast cancer do not provide accurate and comprehensive information, giving few or no data about risk/benefit ratios. We conducted a comparative study among 10 European countries about health information on breast cancer screening, assessing the first 10 Web sites addressing the general public that appeared following an Internet search.With the help of medical residents involved in the EuroNet MRPH Association, we analyzed the first 30 results of an Internet search in 10 European countries to determine the first 10 sites that offered screening mammography. We searched for the following information: source of information, general information on mammography and breast cancer screening, potential harms and risks (false positives, false positives after biopsy, false negatives, interval cancer, overdiagnosis, lead-time bias, and radiation exposure), and potential benefits (reduced mortality and increased survival).The United Kingdom provided the most information: 39 of all 70 possible identified risks (56%) were reported on its sites. Five nations presented over 35% of the possible information (United Kingdom, Spain, France, Ireland, and Italy); the others were under 30% (Portugal, Poland, Slovenia, Netherlands, and Croatia). Regarding the benefits, sites offering the most complete information were those in France (95%) and Poland (90%).Our results suggest that, despite consensus in the scientific community about providing better information to citizens, further efforts are needed to improve information about breast cancer screening. That conclusion also applies to countries showing better results. We believe that there should be greater coordination in this regard throughout Europe.

Artificial intelligence for breast cancer screening: Opportunity or hype?

Interpretation of mammography for breast cancer (BC) screening can confer a mortality benefit through early BC detection, can miss a cancer that is present or fast growing, or can result in false-positives. Efforts to improve screening outcomes have mostly focused on intensifying imaging practices (double instead of single-reading, more frequent screens, or supplemental imaging) that may add substantial resource expenditures and harms associated with population screening. Less attention has been given to making mammography screening practice 'smarter' or more efficient. Artificial intelligence (AI) is capable of advanced learning using large complex datasets and has the potential to perform tasks such as image interpretation. With both highly-specific capabilities, and also possible un-intended (and poorly understood) consequences, this viewpoint considers the promise and current reality of AI in BC detection.