Adverse effects of screening mammography

Attributes, Performance, and Gaps in Current & Emerging Breast Cancer Screening Technologies

Background:

Early detection of breast cancer, combined with effective treatment, can reduce mortality. Millions of women are diagnosed with breast cancer and many die every year globally. Numerous early detection screening tests have been employed. A wide range of current breast cancer screening methods are reviewed based on a series of searchers focused on clinical testing and performance. </P><P> Discussion: The key factors evaluated centre around the trade-offs between accuracy (sensitivity and specificity), operator dependence of results, invasiveness, comfort, time required, and cost. All of these factors affect the quality of the screen, access/eligibility, and/or compliance to screening programs by eligible women. This survey article provides an overview of the working principles, benefits, limitations, performance, and cost of current breast cancer detection techniques. It is based on an extensive literature review focusing on published works reporting the main performance, cost, and comfort/compliance metrics considered.

Conclusion:

Due to limitations and drawbacks of existing breast cancer screening methods there is a need for better screening methods. Emerging, non-invasive methods offer promise to mitigate the issues particularly around comfort/pain and radiation dose, which would improve compliance and enable all ages to be screened regularly. However, these methods must still undergo significant validation testing to prove they can provide realistic screening alternatives to the current accepted standards.

Review of breast screening: Toward clinical realization of microwave imaging

Microwave imaging (MI) technology has come a long way to introduce a noninvasive, inexpensive, fast, convenient, and safe screening tool for clinical breast monitoring. However, there is a niche between the existing understanding of MI by engineers versus clinicians. Our manuscript targets that niche and highlights the state of the art in MI technology compared to the existing breast cancer detection modalities (mammography, ultrasound, molecular imaging, and magnetic resonance). The significance of our review article is in consolidation of up-to-date breast clinician views with the practical needs and engineering challenges of a novel breast screening modality. We summarize breast tissue abnormalities and highlight the benefits as well as potential drawbacks of the MI as a cancer detection methodology. Our goal is to present an article that MI researchers as well as practitioners in the field can use to assess the viability of the MI technology as a competing or complementary modality to the existing means of breast cancer screening.

Time Spent by Breast Imaging Radiologists to Perform Value-Added Activities at an Academic Cancer Center

BACKGROUND

Health care reform in the United States has generated a paradigm shift in the practice of radiology aimed at increasing the degree of patient-centered care. We conducted a study to quantify the amount of time breast imaging radiologists spend on value-added activities at an academic comprehensive cancer center located in Miami, Florida, and accredited by the American College of Radiology as a Breast Imaging Center of Excellence.

METHODS

A prospective, observational study was conducted during a period of 20 consecutive workdays. Three participating breast imaging radiologists maintained a real-time log of each activity performed. A generalized linear model was used to perform a 1-way analysis of variance. An alpha level of .05 was used to determine statistical significance.

RESULTS

The average daily time dedicated to these activities was 92.1 minutes (range, 56.4-132.2). The amount of time significantly differed among breast imaging radiologists and correlated with their assigned daily role (P < .001 for both) but was independent of their years of experience. The daily role that required the most time was the interpretation of diagnostic imaging studies, which is when most interactions with patients, their relatives, and referring physicians occurred. The specific activity that required the most time was preparing for and participating in tumor boards.

CONCLUSIONS

Our findings suggest that the breast imaging radiologists who participated in this study dedicated a significant amount of their time to value-added activities to help improve patients' experience across the continuity of their care. We propose that similar studies be conducted at other institutions to better assess the magnitude of this finding across different breast imaging care settings.

Implications of Overdiagnosis: Impact on Screening Mammography Practices

This review article explores the issue of overdiagnosis in screening mammography. Overdiagnosis is the screen detection of a breast cancer, histologically confirmed, that might not otherwise become clinically apparent during the lifetime of the patient. While screening mammography is an imperfect tool, it remains the best tool we have to diagnose breast cancer early, before a patient is symptomatic and at a time when chances of survival and options for treatment are most favorable. In 2015, an estimated 231,840 new cases of breast cancer (excluding ductal carcinoma in situ) will be diagnosed in the United States, and some 40,290 women will die. Despite these data, screening mammography for women ages 40-69 has contributed to a substantial reduction in breast cancer mortality, and organized screening programs have led to a shift from late-stage diagnosis to early-stage detection. Current estimates of overdiagnosis in screening mammography vary widely, from 0% to upwards of 30% of diagnosed cancers. This range reflects the fact that measuring overdiagnosis is not a straightforward calculation, but usually one based on different sets of assumptions and often biased by methodological flaws. The recent development of tomosynthesis, which creates high-resolution, three-dimensional images, has increased breast cancer detection while reducing false recalls. Because the greatest harm of overdiagnosis is overtreatment, the key goal should not be less diagnosis but better treatment decision tools. (Population Health Management 2015;18:S3-S11).

Automated breast volume scanning versus conventional ultrasound in breast cancer screening

RATIONALE AND OBJECTIVES

To assess the diagnostic value of automated breast volume scanning (ABVS) versus conventional ultrasound (US) in breast cancer screening.

MATERIALS AND METHODS

This study retrospectively analyzed the ABVS and US images from 200 women who underwent breast examination and were recommended for biopsy in our health management centers between July 22, 2011, and October 20, 2013. We retrospectively assessed whether breast lesions from 200 women, which were detected and classified by US, could be detected and classified by an independent examiner using only ABVS findings. The sensitivity and specificity of ABVS versus US in determining lesion malignancy were calculated using biopsy as the gold standard.

RESULTS

In the 200 cases, 273 and 194 individual lesions were detected by ABVS and US, respectively. All 194 US-detected lesions were detected by ABVS. Pathologic examination determined that, of the 273 total lesions, 251 lesions were benign and 22 lesions were malignant. US detected 21 of the 22 malignant lesions and ABVS detected all 22 malignant lesions. The sensitivity and specificity of ABVS relative to biopsy (gold standard) were 28.95% and 100%, whereas the sensitivity and specificity of US relative to biopsy were 43.06% and 98.36%.

CONCLUSIONS

US displays superior sensitivity to ABVS across all Breast Imaging Reporting and Data System (BI-RADS) density categories while displaying equivalent specificity with the exception of BI-RADS density category 1, in which ABVS displayed a slightly superior specificity. As ABVS possesses several advantages and limitations with respect to US, ABVS may serve as an effective, adjunct, screening tool to mammography and conventional sonography.

Screening mammography benefit controversies: sorting the evidence

Numerous clinical studies have confirmed that screening women age 40 years and older reduces breast cancer mortality by 30% to 50%. Several factors including faster breast cancer growth rates and lower breast cancer incidence among younger women, as well as shorter life expectancy and more comorbid conditions among older women, should also be considered in screening guidelines. Annual screening beginning at age 40 years and continuing with no upper age limit, as long as a woman has a life expectancy of at least 5 years and no significant comorbid conditions, is currently recommended.

Is confidence of mammographic assessment a good predictor of accuracy?

OBJECTIVE

Interpretive accuracy varies among radiologists, especially in mammography. This study examines the relationship between radiologists' confidence in their assessments and their accuracy in interpreting mammograms.

MATERIALS AND METHODS

In this study, 119 community radiologists interpreted 109 expert-defined screening mammography examinations in test sets and rated their confidence in their assessment for each case. They also provided a global assessment of their ability to interpret mammograms. Positive predictive value (PPV) and negative predictive value (NPV) were modeled as functions of self-rated confidence on each examination using log-linear regression estimated with generalized estimating equations. Reference measures were cancer status and expert-defined need for recall. Effect modification by weekly mammography volume was examined.

RESULTS

Radiologists who self-reported higher global interpretive ability tended to interpret more mammograms per week (p = 0.08), were more likely to specialize (p = 0.02) and to have completed a fellowship in breast or women's imaging (p = 0.05), and had a higher PPV for cancer detection (p = 0.01). Examinations for which low-volume radiologists were "very confident" had a PPV of 2.93 times (95% CI, 2.01-4.27) higher than examinations they rated with neutral confidence. Trends of increasing NPVs with increasing confidence were significant for low-volume radiologists relative to noncancers (p = 0.01) and expert nonrecalls (p < 0.001). A trend of significantly increasing NPVs existed for high-volume radiologists relative to expert nonrecall (p = 0.02) but not relative to noncancer status (p = 0.32).

CONCLUSION

Confidence in mammography assessments was associated with better accuracy, especially for low-volume readers. Asking for a second opinion when confidence in an assessment is low may increase accuracy.

An abnormal screening mammogram causes more anxiety than a palpable lump in benign breast disease

Being recalled for further diagnostic procedures after an abnormal screening mammogram (ASM) can evoke a high state anxiety with lowered quality of life (QoL). We examined whether these adverse psychological consequences are found in all women with benign breast disease (BBD) or are particular to women referred after ASM. In addition, the influence of the anxiety as a personality characteristic (trait anxiety) was studied. Between September 2002 and February 2010 we performed a prospective longitudinal study in six Dutch hospitals. Women referred after ASM or with a palpable lump in the breast (PL), who were subsequently diagnosed with BBD, were included. Before diagnosis (at referral) and during follow-up, questionnaires were completed examining trait anxiety (at referral), state anxiety, depressive symptoms (at referral, one, three and 6 months after diagnosis), and QoL (at referral and 12 months). Women referred after ASM (N=363) were compared with women with PL (N=401). A similar state anxiety score was found in both groups, but a lower psychological QoL score at 12 months was seen in the ASM group. In women with not-high trait anxiety those in the ASM group were more anxious with more depressive symptoms at referral, and reported impaired psychological QoL at referral and at 12 months compared with the PL group. No differences were found between ASM and PL in women with high trait anxiety, but this group scored unfavorably on anxiety, depressive symptoms and QoL compared with women with not-high trait anxiety. ASM evokes more anxiety and depressive symptoms and lowered QoL compared with women referred with PL, especially in women who are not prone to anxiety. Women should be fully informed properly about the risks and benefits of breast cancer screening programs. We recommend identifying women at risk of reduced QoL using a psychometric test.

Anxiety after an abnormal screening mammogram is a serious problem

PURPOSE

The aim of this study was to analyze the possible negative psychological consequences of a false positive screening mammogram (FPSM). We compared anxiety evoked by first (FSM) versus repeat screening mammogram (RSM). Questionnaires were completed prior to the diagnosis and during follow up.

RESULTS

No differences in anxiety, depressive symptoms, and Quality of Life (QoL) were found between FSM (N = 186) or RSM (N = 296) groups. All women experienced high anxiety before diagnosis was known. High trait anxiety was predictive for more anxiety, depressive symptoms, and lower QoL. Women with low score on trait anxiety were more momentary anxious in FSM group compared with RSM group (p = 0.048).

CONCLUSION

Negative psychological consequences after an FPSM are seen in all women. These effects are strengthened by personality and timing of the screening mammogram. All women should receive correct information concerning the negative psychological effects and should be offered psychosocial support if needed.

Impact of a CAD system in a screen-film mammography screening program: a prospective study

OBJECTIVE

The purpose of our study was to perform a prospective assessment of the impact of a CAD system in a screen-film mammography screening program during a period of 3 years.

MATERIALS AND METHODS

Our study was carried out on a population of 21,855 asymptomatic women (45-65 years). Mammograms were processed in a CAD system and independently interpreted by one of six radiologists. We analyzed the following parameters: sensitivity of radiologist's interpretation (without and with CAD), detection increase, recall rate and positive predictive value of biopsy, CAD's marks, radiologist's false negatives and comparative analysis of carcinomas detected and non-detected by CAD.

RESULTS

Detection rate was 4.3‰. CAD supposed an increase of 0.1‰ in detection rate and 1% in the total number of cases (p<0.005). The impact on recall rate was not significant (0.4%) and PPV of percutaneous biopsy was unchanged by CAD (20.23%). CAD's marks were 2.7 per case and 0.7 per view. Radiologist's false negatives were 13 lesions which were initially considered as CAD's false positives.

CONCLUSIONS

CAD supposed a significant increase in detection, without modifications in recall rates and PPV of biopsy. However, better results could have been achieved if radiologists had considered actionable those cases marked by CAD but initially misinterpreted.

Auditing and benchmarks in screening and diagnostic mammography

Radiologists can use outcome data such as cancer size and stage to determine how well their own practice provides benefit to their patients and can use measures such as screening recall rates and positive predictive values to assess how well adverse consequences are being contained. New data on national benchmarks for screening and diagnostic mammography in the United States allow radiologists to evaluate their own performance with respect to their peers. This article discusses recommended outcome values in the United States and Europe, current Mammography Quality Standards Act audit requirements, and Institute of Medicine proposals for future requirements.

Medical directors of breast imaging centers: beyond films

Over the past decade, breast radiologists have been increasingly asked to fulfill a new dynamic role as medical directors of breast imaging centers. To our knowledge, there are no standardized job descriptions nor defined roles and responsibilities for this position. Job descriptions are usually crafted to fit unique institutional and individual situations. To be an effective medical director of a breast imaging center, breast imagers must be more than just film readers. In this article, the authors describe the diverse roles of contemporary medical directors of breast imaging centers.

United States radiological health activities: inspection results of mammography facilities

Purpose:

The Mammography Quality Standards Act (MQSA) was enacted in 1992 to set national standards for high-quality mammography, including standards for mammographic X-ray equipment, patient dose, clinical image quality, and related technical parameters. The MQSA also requires minimum qualifications for radiologic technologists, interpreting physicians and medical physicists, mandates acceptable practices for quality-control, quality-assurance, and requires processes to audit medical outcomes. This paper presents the findings of MQSA inspections of facilities, which characterize significant factors affecting mammography quality in the United States.

Materials and Methods:

Trained inspectors collected data regarding X-ray technical factors, made exposure measurements for the determination of mean glandular dose (MGD), evaluated image quality, and inspected the quality of the film-processing environment. The average annual facility and total U.S. screening exam workloads were computed using workload data reported by facilities.

Results:

Mammography facilities have made technical improvements as evidenced by a narrower distribution of doses, higher phantom-film background optical densities associated with higher phantom image-quality scores, and better film processing. It is estimated that approximately 36 million screening mammography exams were conducted in 2006, a rate that is almost triple the exam volume estimated for 1997. Digital mammography (DM) is now in use at approximately 14% (1,191 of 8,834) of MQSA-certified mammography facilities. The results indicate that DM can offer lower dose to the patient while providing comparable or better image quality.

Analysis of a mammography teaching program based on an affordance design model

RATIONALE AND OBJECTIVES

The wide use of computer technology in education, particularly in mammogram reading, asks for e-learning evaluation. The existing media comparative studies, learner attitude evaluations, and performance tests are problematic. Based on an affordance design model, this study examined an existing e-learning program on mammogram reading.

MATERIALS AND METHODS

The selection criteria include content relatedness, representativeness, e-learning orientation, image quality, program completeness, and accessibility. A case study was conducted to examine the affordance features, functions, and presentations of the selected software. Data collection and analysis methods include interviews, protocol-based document analysis, and usability tests and inspection. Also some statistics were calculated.

RESULTS

The examination of PBE identified that this educational software designed and programmed some tools. The learner can use these tools in the process of optimizing displays, scanning images, comparing different projections, marking the region of interests, constructing a descriptive report, assessing one's learning outcomes, and comparing one's decisions with the experts' decisions. Further, PBE provides some resources for the learner to construct one's knowledge and skills, including a categorized image library, a term-searching function, and some teaching links. Besides, users found it easy to navigate and carry out tasks. The users also reacted positively toward PBE's navigation system, instructional aids, layout, pace and flow of information, graphics, and other presentation design.

CONCLUSION

The software provides learners with some cognitive tools, supporting their perceptual problem-solving processes and extending their capabilities. Learners can internalize the mental models in mammogram reading through multiple perceptual triangulations, sensitization of related features, semantic description of mammogram findings, and expert-guided semantic report construction. The design of these cognitive tools and the software interface matches the findings and principles in human learning and instructional design. Working with PBE's case-based simulations and categorized gallery, learners can enrich and transfer their experience to their jobs.

Polymorphisms in DNA repair genes, medical exposure to ionizing radiation, and breast cancer risk

An epidemiologic study was conducted to determine whether polymorphisms in DNA repair genes modify the association between breast cancer risk and exposure to ionizing radiation. Self-reported exposure to ionizing radiation from medical sources was evaluated as part of a population-based, case-control study of breast cancer in African-American (894 cases and 788 controls) and White (1,417 cases and 1,234 controls) women. Genotyping was conducted for polymorphisms in four genes involved in repair of radiation-induced DNA damage, the double-strand break repair pathway: X-ray cross-complementing group 3 (XRCC3) codon 241 Thr/Met, Nijmegen breakage syndrome 1 (NBS1) codon 185 Glu/Gln, X-ray cross-complementing group 2 (XRCC2) codon 188 Arg/His, and breast cancer susceptibility gene 2 (BRCH2) codon 372 Asn/His. Allele and genotype frequencies were not significantly different in cases compared with controls for all four genetic polymorphisms, and odds ratios for breast cancer were close to the null. Combining women with two, three, and four variant genotypes, a positive association was observed between breast cancer and number of lifetime mammograms (P(trend) < 0.0001). No association was observed among women with zero or one variant genotype (P = 0.86). Odds ratios for radiation treatments to the chest and number of lifetime chest X-rays were slightly elevated but not statistically significant among women with two to four variant genotypes. The study has several limitations, including inability to distinguish between diagnostic and screening mammograms or reliably classify prediagnostic mammograms and chest X-rays in cases. Prospective studies are needed to address whether common polymorphisms in DNA repair genes modify the effects of low-dose radiation exposure from medical sources.

CAD-aided mammogram training

RATIONALE AND OBJECTIVES

Although computer-aided detection (CAD) improves the diagnosis rate of early breast cancer, it has not been well integrated into radiology residency and technician training program. Moreover, CAD performance studies ignore the reader's training and experience with CAD. The purpose of this study was to investigate whether CAD training via a cognitive-perceptual based hypermedia program has effects on the performance studies of mammogram reading.

MATERIALS AND METHODS

Three observers read a pretest set of 80 breast cancer cases (43 negative, 23 benign, and 14 malignant cancer cases). During 4 weeks' training, the observers used a hypermedia instructional program in CAD-aided mammography interpretation. The program includes modules of CAD attention-focusing schemes, CAD procedural knowledge, and case-based simulations in mammography interpretation in consensus with CAD. By the end of the fourth week of the training, they reviewed a posttest set of cases. Data were analyzed with multireader, multicase receiver operating characteristic methods.

RESULTS

Three readers performed better in mammogram reading after training in CAD knowledge than they did before CAD training. CAD training and experience improved the performance of CAD-aided mammography interpretation.

CONCLUSION

A statistically significant difference was found in each observer's performance in CAD-aided mammogram reading before and after the training. CAD training will influence the perception, recognition, and interpretation of early breast cancer and CAD performance studies. Furthermore, the young generation of radiologic professionals can have more training in various attention-focusing features, declarative knowledge, procedural knowledge, and conditional knowledge of CAD and incorporate them into their knowledge base and strategic processing for the purpose of improving the accuracy of mammography interpretation performance.

Screening Mammography Controversies: Resolved, Partly Resolved, and Unresolved

Since the 1960s, multiple randomized clinical trials have measured differences in breast cancer mortality between women 40 and 70 years of age who were offered screening mammography and control group women. This article describes briefly these trials, which nearly universally documented statistically significant reductions in breast cancer deaths. These trials also underestimated the benefit, regardless of age, due to screening parameters that were not optimized. In recent years, published articles analyzing studies of Swedish women have claimed that there is no reduction in overall mortality from breast cancer and other causes among women offered screening. Critical assessment of these articles noted that breast cancer deaths were less than 5% of all deaths and that no statistically significant reduction in overall mortality rates should be expected within the population that had been analyzed. The latest screening mammography controversies involve potential adverse consequences and risks, such as X-ray exposure, detection of ductal carcinoma in situ (DCIS), and "excessive" callback rates for additional imaging studies. Despite these controversies, the preponderance of scientific evidence continues to strongly support annual screening mammography for women 40 years of age and older.