Screen-film Mammography Research Articles

Breast Cancer: Missed Interval and Screening-detected Cancer at Full-Field Digital Mammography and Screen-Film Mammography— Results from a Retrospective Review

To compare the percentages and mammographic features of cancers missed at full-field digital mammography (FFDM) and screen-film mammography (SFM) in women who participated in the Norwegian Breast Cancer Screening Program in 2002-2008. Social Science Data Services approval was obtained; the requirement for informed consent was waived. Cases were all the interval and screening-detected cancers from 35 127 FFDM and 52 444 SFM examinations in two Norwegian counties. Prior and diagnostic FFDM examinations of 49 interval and 86 screening-detected breast cancers were reviewed by four breast radiologists and compared with a review of SFM examinations of 81 interval and 123 screening-detected cancers. Cancers were classified as missed or true, mammographic features were described, percentages were compared by using the χ(2) or Fisher exact test, and 95% confidence intervals (CIs) were calculated. The percentages of interval and screening-detected cancers missed at FFDM and SFM did not differ significantly. (interval cancers missed: 33% [16 of 49] at FFDM vs 30% [24 of 81] at SFM [P = .868]; screening-detected cancers missed: 20% [17 of 86] at FFDM vs 21% [26 of 123] at SFM [P = .946]). Asymmetry was present in 27% (95% CI: 13.3%, 45.5%) of prior mammograms of cancers missed at FFDM and 10% (95% CI: 3.3%, 21.8%) of those missed at SFM (P = .070). Calcifications were observed in 18% (95% CI: 7.0%, 35.5%) of the cancers missed at FFDM and 34% (95% CI: 21.2%, 48.8%) of those missed at SFM (P = .185). Average mammographic tumor size of missed cancers manifesting as masses was 10.4 mm at FFDM and 13.6 mm at SFM (P = .036). The use of FFDM has not reduced the challenge of missed cancers. Cancers missed at FFDM tend to have different mammographic features than those missed at SFM.

A comparison of the accuracy of film-screen mammography, full-field digital mammography, and digital breast tomosynthesis

To measure the change in diagnostic accuracy of conventional film-screen mammography and full-field digital mammography (FFDM) with the addition of digital breast tomosynthesis (DBT) in women recalled for assessment following routine screening. Ethics approval for the study was granted. Women recalled for assessment following routine screening with screen-film mammography were invited to participate. Participants underwent bilateral, two-view FFDM and two-view DBT. Readers scored each lesion separately for probability of malignancy on screen-film mammography, FFDM, and then DBT. The scores were compared with the presence or absence of malignancy based on the final histopathology outcome. Seven hundred and thirty-eight women participated (93.2% recruitment rate). Following assessment 204 (26.8%) were diagnosed as malignant (147 invasive and 57 in-situ tumours), 286 (37.68%) as benign, and 269 (35.4%) as normal. The diagnostic accuracy was evaluated by using receiving operating characteristic (ROC) and measurement of area under the curve (AUC). The AUC values demonstrated a significant (p=0.0001) improvement in the diagnostic accuracy with the addition of DBT combined with FFDM and film-screen mammography (AUC=0.9671) when compared to FFDM plus film-screen mammography (AUC=0.8949) and film-screen mammography alone (AUC=0.7882). The effect was significantly greater for soft-tissue lesions [AUC was 0.9905 with the addition of DBT and AUC was 0.9201 for FFDM with film-screen mammography combined (p=0.0001)] compared to microcalcification [with the addition of DBT (AUC=0.7920) and for FFDM with film-screen mammography combined (AUC=0.7843; p=0.3182)]. The addition of DBT increases the accuracy of mammography compared to FFDM and film-screen mammography combined and film-screen mammography alone in the assessment of screen-detected soft-tissue mammographic abnormalities.

Mammography screening using independent double reading with consensus: Is there a potential benefit for computer-aided detection?

Double reading improves the cancer detection rate in mammography screening. Single reading with computer-aided detection (CAD) has been considered to be an alternative to double reading. Little is known about the potential benefit of CAD in breast cancer screening with double reading. To compare prospective independent double reading of screen-film (SFM) and full-field digital (FFDM) mammography in population-based screening with retrospective standalone CAD performance on the baseline mammograms of the screen-detected cancers and subsequent cancers diagnosed during the follow-up period. The study had ethics committee approval. A 5-point rating scale for probability of cancer was used for 23,923 (SFM = 16,983; FFDM = 6940) screening mammograms. Of 208 evaluable cancers, 104 were screen-detected and 104 were subsequent (44 interval and 60 next screening round) cancers. Baseline mammograms of subsequent cancers were retrospectively classified in consensus without information about cancer location, histology, or CAD prompting as normal, non-specific minimal signs, significant minimal signs, and false-negatives. The baseline mammograms of the screen-detected cancers and subsequent cancers were evaluated by CAD. Significant minimal signs and false-negatives were considered 'actionable' and potentially diagnosable if correctly prompted by CAD. CAD correctly marked 94% (98/104) of the baseline mammograms of the screen-detected cancers (SFM = 95% [61/64]; FFDM = 93% [37/40]), including 96% (23/24) of those with discordant interpretations. Considering only those baseline examinations of subsequent cancers prospectively interpreted as normal and retrospectively categorized as 'actionable', CAD input at baseline screening had the potential to increase the cancer detection rate from 0.43% to 0.51% (P = 0.13); and to increase cancer detection by 16% ([104 + 17]/104) and decrease interval cancers by 20% (from 44 to 35). CAD may have the potential to increase cancer detection by up to 16%, and to reduce the number of interval cancers by up to 20% in SFM and FFDM screening programs using independent double reading with consensus review. The influence of true- and false-positive CAD marks on decision-making can, however, only be evaluated in a prospective clinical study.

Situación de la investigación en el cribado de cáncer de mama en España: implicaciones para la prevención

ObjectiveThe consolidation of breast cancer screening programs, with full coverage of the target population in all Spanish regions, has encouraged the beginning of a joint research strategy. This strategy aims to improve the effectiveness of breast cancer screening by gathering information from distinct screening programs. MethodsA retrospective cohort with information on over 1.5 million screened women was constructed to evaluate risk factors for a false-positive result. The impact of the change from digital mammography to screen-film mammography was evaluated, while results for interval cancers and false negatives are currently being studied. ResultsThe results are highly useful from the perspective of public health, as they can be used to identify and improve the information provided to women with a higher risk of experiencing an adverse effect. These results will also be helpful to identify screening program-related characteristics and women's personal characteristics, which will allow better prevention strategies to be developed. ConclusionsThe results obtained will be included in mathematical models currently under development to evaluate the efficiency of breast cancer screening. These models could be highly useful to provide information and guide clinical and health policy decisions on cancer prevention and control.

유방암 환자의 Digital Mammography에 관한 연구

본 연구는 유방영상검사의 최고의 관심영역인 DR 방식의 유방영상에서 유방암 진단의 정확도를 평가하고, 유방암 환자들의 특성을 알아보고자 DR 방식으로 유방영상검사를 실시한 유방암 환자 57명을 대상으로 2010년 5월부터 2011년 6월까지 조사되었다. 유방암 환자들의 평균 나이는 50.8세이었고, 유방암의 발생 부위는 상외측(UOQ)이 전체의 33.3%로 가장 많은 것으로 조사되었다. 연령에 따른 유방암 발생은 40-49세에서 42.1%로 모든 연령대에서 가장 높게 나타났다. 유방암 환자들의 유방조직 밀도는 지방형 유방이 31.6%(18/57), 치밀유방이 68.4%(39/57)로 나타나, 70%에 가까운 유방암 환자들이 치밀유방의 형태를 띠고 있었다. 유방영상에서 방사선학적 병변 중 종괴와 미세석회화가 함께 동반된 경우 (45.3%)가 유방암 발견율이 가장 높은 것으로 조사되었고, 치밀유방에서 미세석회화를 동반하지 않는 종괴의 경우 지방형 유방에서보다 유방암의 발견율이 더 낮은 것으로 조사되었으며, 이러한 종괴는 치밀유방에서 위음성율을 높이는 원인이 되고 있다. Digital mammography의 위음성률은 7.0%이었고, 민감도는 93.0%인 것으로 조사되었다. 치밀유방의 위음성율은 12.8%, 민감도는 87.2%로 조사되었는데 이는 이전에 보고된 screen film mammography의 치밀유방에서 보다 유방암에 대한 민감도가 더 높은 것으로 조사되었다. This study aimed to evaluate the accuracy of breast cancer diagnosis of digital mammography which is in the highest interest of breast imaging test, and to investigate the characteristics of breast cancer patients. For this purpose, 57 breast cancer patients who underwent breast imaging test were examined between May 2010 and June 2011. The average age of the breast cancer patients was 50.8 years old, and the most frequently occurring location was the upper outer quadrant (UOQ), accounting for 33.3%. By age, the highest occurrence rate of breast cancer was the age group of 40~49, accounting for 42.1%. As for the breast composition of the breast cancer patients, fatty breast accounted for 31.6% (18/57) and dense breast for 68.4% (39/57), indicating that nearly 70% of the breast cancer patients have dense breast. It was found that the detection rate of breast cancer was the highest (45.3%) when both microcalcification and mass are simultaneously present in the radiographic lesion of the breast imaging. In dense breast, the mass without microcalcification was lower in detection rate than fatty breast. Accordingly, the mass is the cause of raising the false negative rate in dense breast. The findings show that the false negative rate of digital mammography was 7.0% and the sensitivity 93.0%. Also, the false negative rate of dense breast was 12.8%, and the sensitivity 87.2%, indicating that the sensitivity to breast cancer in this study was higher than the dense breast of previously reported screen film mammography.

Comparative Effectiveness of Digital Versus Film-Screen Mammography

Letters7 February 2012Comparative Effectiveness of Digital Versus Film-Screen MammographyKarla Kerlikowske, MD and Rebecca Hubbard, PhDKarla Kerlikowske, MDFrom San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, and Group Health Research Institute, Seattle, WA 98101-1448.Search for more papers by this author and Rebecca Hubbard, PhDFrom San Francisco Veterans Affairs Medical Center, San Francisco, CA 94121, and Group Health Research Institute, Seattle, WA 98101-1448.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-156-3-201202070-00024 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail IN RESPONSE:We compared the interpretative performance of digital versus film-screen mammography in community practice and were reassured to find that no subgroups of women have substantially worse performance with either modality. In fact, digital mammography tended to perform as well or slightly better in most subgroups. Dr. Keen suggests that if we had taken use of computer-aided detection into account, we would have found less favorable performance results for digital compared with film-screen mammography because computer-aided detection is widely used to interpret digital mammograms. Computer-aided detection was more commonly used for digital than for film-screen mammography (56% vs. 23%) ...

Comparative Effectiveness of Digital Versus Film-Screen Mammography

Letters7 February 2012Comparative Effectiveness of Digital Versus Film-Screen MammographyStephan Imfeld, MDStephan Imfeld, MDFrom University Hospital, 4054 Basel, Switzerland.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-156-3-201202070-00022 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail TO THE EDITOR:I read with interest the recent study by Kerlikowske and colleagues (1), who compared the accuracy of digital mammography with that of film-screen mammography in a large, population-based cohort of community-based imaging facilities.The overall statistics of the main results show a small but statistically significant difference in specificity (0.6%; P < 0.001) and no statistical difference in sensitivity (P = 0.21). Nevertheless, the main focus, as described in the abstract, is a subgroup analysis of the latter, comparing sensitivity for different estrogen-receptor status and age strata without any statistical adjustment for multiple testing.Subgroup analyses of variables with ...

Comparative Effectiveness of Digital Versus Film-Screen Mammography

Comparative Effectiveness of Digital Versus Film-Screen Mammography

Comparative Effectiveness of Digital Versus Film-Screen Mammography

Comparative Effectiveness of Digital Versus Film-Screen Mammography

Computerized Analysis of Mammographic Parenchymal Patterns on a Large Clinical Dataset of Full-Field Digital Mammograms: Robustness Study with Two High-Risk Datasets

The purpose of this study was to demonstrate the robustness of our prior computerized texture analysis method for breast cancer risk assessment, which was developed initially on a limited dataset of screen-film mammograms. This current study investigated the robustness by (1) evaluating on a large clinical dataset, (2) using full-field digital mammograms (FFDM) as opposed to screen-film mammography, and (3) incorporating analyses over two types of high-risk patient sets, as well as patients at low risk for breast cancer. The evaluation included the analyses on the parenchymal patterns of women at high risk of developing of breast cancer, including both BRCA1/2 gene mutation carriers and unilateral cancer patients, and of women at low risk of developing breast cancer. A total of 456 cases, including 53 women with BRCA1/2 gene mutations, 75 women with unilateral cancer, and 328 low-risk women, were retrospectively collected under an institutional review board approved protocol. Regions-of-interest (ROIs), were manually selected from the central breast region immediately behind the nipple. These ROIs were subsequently used in computerized feature extraction to characterize the mammographic parenchymal patterns in the images. Receiver operating characteristic analysis was used to assess the performance of the computerized texture features in the task of distinguishing between high-risk and low-risk subjects. In a round robin evaluation on the FFDM dataset with Bayesian artificial neural network analysis, AUC values of 0.82 (95% confidence interval [0.75, 0.88]) and 0.73 (95% confidence interval [0.67, 0.78]) were obtained between BRCA1/2 gene mutation carriers and low-risk women, and between unilateral cancer and low-risk women, respectively. These results from computerized texture analysis on digital mammograms demonstrated that high-risk and low-risk women have different mammographic parenchymal patterns. On this large clinical dataset, we validated our methods for quantitative analyses of mammographic patterns on FFDM, statistically demonstrating again that women at high risk tend to have dense breasts with coarse and low-contrast texture patterns.

The readout thickness versus the measured thickness for a range of screen film mammography and full-field digital mammography units

To establish a simple method to determine breast readout accuracy on mammography units. A thickness measuring device (TMD) was used in conjunction with a breast phantom. This phantom had compression characteristics similar to human female breast tissue. The phantom was compressed, and the thickness was measured using TMD and mammography unit readout. Measurements were performed on a range of screen film mammography (SFM) and full-field digital mammography (FFDM) units (8 units in total; 6 different models/manufacturers) for two different sized paddles and two different compression forces (60 and 100 N). The difference between machine readout and TMD for the breast area, when applying 100 N compression force, for nonflexible paddles was largest for GE Senographe DMR+ (24 cm × 30 cm paddle: +14.3%). For flexible paddles the largest difference occurred for Hologic Lorad Selenia (18 cm × 24 cm paddle: +26.0%). None of the units assessed were found to have perfect correlation between measured and readout thickness. TMD measures and thickness readouts were different for the duplicate units from two different models/manufacturers.

Diagnostic quality of 50 and 100 µm computed radiography compared with screen–film mammography in operative breast specimens

To compare reader ratings of the clinical diagnostic quality of 50 and 100 μm computed radiography (CR) systems with screen-film mammography (SFM) in operative specimens. Mammograms of 57 fresh operative breast specimens were analysed by 10 readers. Exposures were made with identical position and compression with three mammographic systems (Fuji 100CR, 50CR and SFM). Images were anonymised and readers blinded to the CR system used. A five-point comparative scoring system (-2 to +2) was used to assess seven quality criteria and overall diagnostic value. Statistical analysis was subsequently performed of reader ratings (n = 16,925). For most quality criteria, both CR systems were rated as equivalent to or better than SFM. The CR systems were significantly better at demonstrating skin edge and background tissue (p < 1 × 10(-5)). Microcalcification was best demonstrated on the CR50 system (p < 1 × 10(-5)). The overall diagnostic value of both CR systems was rated as being as good as or better than SFM (p < 1 × 10(-5)). In this clinical setting, the overall diagnostic performance of both CR systems was as good as or better than SFM, with the CR50 system performing better than the CR100.

Enriched designs for assessing discriminatory performance — analysis of bias and variance

In evaluating discriminatory performance of a new modality in a screening setting, a logistical constraint is that the prevalence of the disease of interest is typically very low. This implies that under a standard study design large numbers of subjects have to be evaluated using the new modality. However, if a predicate modality exists in clinical practice, one can base inclusion into the study of the new modality on the clinical results from the predicate to 'enrich' the population of diseased subjects in the study. If this enrichment is not accounted for when estimating sensitivity, specificity, and area under the ROC curve, these 'naive' estimates may be substantially biased compared with expected performance in the intended use population. We derive expressions for the magnitude of this bias in terms of correlations of modality scores. When such estimates are 'corrected' for the sampling weights using inverse probability weighting, the variances of the estimates of the above quantities are affected. We derive here analytic expressions for these variances. For a fixed number of diseased subjects, differential sampling increases the variance of the (corrected) estimates, all other things being equal. However, differential sampling also increases the number with disease for fixed total study size, which decreases the variance of the sensitivity and area under the ROC curve estimates, all other things being equal. The balance of these two effects determines the gain in efficiency when using enrichment and corrected estimates. These principles are illustrated with a simulation study motivated by the Digital Mammographic Imaging Screening Trial study, a trial of digital versus screen film mammography.

Comparative Effectiveness of Digital Versus Film-Screen Mammography in Community Practice in the United States

Few studies have examined the comparative effectiveness of digital versus film-screen mammography in U.S. community practice. To determine whether the interpretive performance of digital and film-screen mammography differs. Prospective cohort study. Mammography facilities in the Breast Cancer Surveillance Consortium. 329,261 women aged 40 to 79 years underwent 869 286 mammograms (231 034 digital; 638 252 film-screen). Invasive cancer or ductal carcinoma in situ diagnosed within 12 months of a digital or film-screen examination and calculation of mammography sensitivity, specificity, cancer detection rates, and tumor outcomes. Overall, cancer detection rates and tumor characteristics were similar for digital and film-screen mammography, but the sensitivity and specificity of each modality varied by age, tumor characteristics, breast density, and menopausal status. Compared with film-screen mammography, the sensitivity of digital mammography was significantly higher for women aged 60 to 69 years (89.9% vs. 83.0%; P = 0.014) and those with estrogen receptor-negative cancer (78.5% vs. 65.8%; P = 0.016); borderline significantly higher for women aged 40 to 49 years (82.4% vs. 75.6%; P = 0.071), those with extremely dense breasts (83.6% vs. 68.1%; P = 0.051), and pre- or perimenopausal women (87.1% vs. 81.7%; P = 0.057); and borderline significantly lower for women aged 50 to 59 years (80.5% vs. 85.1%; P = 0.097). The specificity of digital and film-screen mammography was similar by decade of age, except for women aged 40 to 49 years (88.0% vs. 89.7%; P < 0.001). Statistical power for subgroup analyses was limited. Overall, cancer detection with digital or film-screen mammography is similar in U.S. women aged 50 to 79 years undergoing screening mammography. Women aged 40 to 49 years are more likely to have extremely dense breasts and estrogen receptor-negative tumors; if they are offered mammography screening, they may choose to undergo digital mammography to optimize cancer detection. National Cancer Institute.

Screening for Breast Cancer with Sonography

Mammography is the standard screening modality for breast cancer; however, sensitivity reduces with increasing breast density, resulting in the potential for masking of cancer. Ultrasound is a potential supplemental screening tool, but its routine use is controversial.A database search was performed with keywords “ultrasound” and “breast density and screening”, including variations. Articles were included if they assessed the use of hand-held ultrasound as a supplemental screening modality in women with dense breasts.Twelve articles were identified. No high-level evidence articles were identified. Cancer detection rates increased with the addition of ultrasound-to-mammography screening protocols. However, this was associated with increased costs per cancer detected, an increased biopsy rate, and a low positive predictive value. The survival benefit, cost versus benefit, and psychological impact of the addition of ultrasound is unknown.The addition of ultrasound to a screening program in an asymptomatic population of women with dense breast tissue detects additional cancers compared with mammography alone. Knowledge regarding a survival or cost benefit associated with increased cancer detection, and the psychological impact of the addition of ultrasound is unknown. Further research is needed to assess whether the addition of ultrasound is cost-effective with respect to clinical outcome and survival.La mammographie est la modalité de dépistage standard pour le cancer du sein; cependant, la sensibilité diminue avec l’augmentation de la densité du tissu mammaire, entraînant une possibilité de masquage du cancer. L’échographie est un outil de dépistage supplémentaire potentiel, mais son utilisation de routine suscite une certaine controverse.Une recherche documentaire a été faire à l’aide des mots-clés « ultrasound », « breast density » et « screening », avec leurs variations. Les articles ont été retenus s’ils évaluaient l’utilisation des appareils d’échographie à baguette comme modalité de dépistage supplémentaire pour les femmes présentant une densité élevée du tissu mammaire.Douze articles ont été recensés, mais aucun présentant des données probantes de haut niveau. Les taux de détection du cancer ont augmenté avec l’ajout de l’échographie aux protocoles de dépistage par mammographie. Cette augmentation était cependant associée à une augmentation du coût par cancer détecté, une augmentation du nombre de biopsies et une faible valeur de prédiction positive. L’avantage au plan du taux de survie, le rapport coût-avantage et l’incidence psychologique de l’ajout de l’échographie sont inconnus.L’ajout de l’échographie à un programme de dépistage au sein d’une population asymptomatique de femmes présentant une densité élevée du tissu mammaire permet de détecter des cancers additionnels par rapport à la mammographie utilisée seule. L’avantage sur le plan du taux de survie ou des coûts associé à un taux de détection plus élevé est inconnu, tout comme l’incidence psychologique de l’ajout de l’échographie. Des recherches plus poussées sont nécessaires afin d’évaluer si l’ajout de l’échographie présente un rapport coût-avantage positif en matière de résultat clinique et de survie.

First report of introducing population-based breast cancer screening in Poland: Experience of the 3-million population region of Lower Silesia

Background: To achieve a reduction in breast cancer mortality in Poland a nation-wide population-based screening was introduced in 2007. Aim: To assess the quality of breast cancer screening programme during the first round of operation in Lower Silesia—a region of over 3 million inhabitants. Methods: Women aged 50–69 are invited for screening, with the exception of those undergoing treatment or being followed up after treatment for breast cancer. Biennial two-view screen-film mammography is used as the standard screening test. Quality evaluation was carried out via early performance indicators. These parameters were calculated according to European Guidelines and compared with recommended levels. Results: Only 40% of women from the eligible population were screened. Among programme attendees the technical recall rate (a repeat mammogram because of technical inadequacy of the screening mammogram) was 0.27%. Further assessment rate (additional diagnostic techniques, either non-invasive or invasive, performed for medical reasons in order to clarify the nature of a perceived abnormality detected at the screening mammography) was 6.2%, while the short-term recall rate (early re-screen mammography at an interval less than the routine round length of the programme) was 2.4%. Cancer detection rate was 6.6/1000 while cancer detection rate expressed as a multiple of the expected breast cancer incidence rate was 3.8. Positive predictive values of the screening test and the further assessment were 11% and 77%, respectively. Conclusion: The general assessment using early indicators reveals that diagnostic service conforms to the European standards on an acceptable or even desirable level. The only exception among these parameters is a too high short-term recall rate, which should be drastically decreased during the next rounds to improve the cost-effectiveness. The main disadvantage of the screening programme at its start is a dramatically poor coverage of the eligible population. If the invitation policy is not significantly intensified the breast cancer mortality rate will not be reduced, despite the good quality of diagnostic service.

P1-309 Differences in radiological patterns, tumour characteristics and diagnostic precision between digital mammography and screen-film mammography in four breast cancer screening programs in Spain

IntroductionSince 2000 Digital Mammography (DM) has been commercially available and implemented in many breast cancer screening programs. Although available information suggests that differences, if exist, are low, complete evaluation of...

Digital mammography screening: Weighing reduced mortality against increased overdiagnosis

Objective Digital mammography has been shown to increase the detection of ductal carcinoma in situ (DCIS) compared to screen-film mammography. The benefits and risks of such an increase were assessed. Methods Breast cancer detection rates were compared between 502,574 screen-film and 83,976 digital mammograms performed between 2004 and 2006 among Dutch screening participants. The detection rates were then modeled using a baseline model and two extreme models that respectively assumed a high rate of progression and no progression of preclinical DCIS to invasive cancer. With these models, breast cancer mortality and overdiagnosis were predicted. Results The DCIS detection rate was significantly higher at digital mammography (1.2 per 1000 mammograms (95% C.I. 1.0–1.5)) than at screen-film mammography (0.7 per 1000 mammograms (95% C.I. 0.6–0.7)). Consequently, 287 (range progressive- non progressive model: 1–598) extra breast cancer deaths per 1,000,000 women (a 4.4% increase) were predicted to be prevented. An extra 401 (range: 165–2271) cancers would be overdiagnosed (a 21% increase). Conclusion Modeling predicted that digital mammography screening would further reduce breast cancer mortality by 4.4%, at a 21% increased overdiagnosis rate. The consequences of digital screening, however, are sensitive to underlying assumptions on the natural history of DCIS.

Differences in radiological patterns, tumour characteristics and diagnostic precision between digital mammography and screen-film mammography in four breast cancer screening programmes in Spain

To compare tumour characteristics between cancers detected with screen-film mammography (SFM) and digital mammography (DM) and to evaluate changes in positive predictive values (PPVs) for further assessments, for invasive procedures and for distinct radiological patterns in recalled women. 242,838 screening mammograms (171,191 SFM and 71,647 DM) from 103,613 women aged 45-69 years, performed in four population-based breast cancer screening programmes in Spain, were included. The tumour characteristics and PPVs of each group were compared. Radiological patterns (masses, calcifications, distortions and asymmetries) among recalled women were described and PPVs were evaluated. The percentages of ductal carcinoma in situ (DCIS) were higher in DM than in SFM both in the first [18.5% vs. 15.8%(p = 0.580)] and in successive screenings [23.2% vs. 15.7%(p = 0.115)]. PPVs for masses, asymmetries and calcifications were higher in DM, being statistically significant in masses (5.3% vs. 3.9%; proportion ratio: 1.37 95%CI: 1.08-1.72). Among cancers detected by calcifications, the percentage of DCIS was higher in DM (60.3% vs. 46.4%, p = 0.060). PPVs were higher when DM was used, both for further assessments and for invasive procedures, with similar cancer detection rates and no statistically significant differences in tumour characteristics. The greatest improvements in PPVs were found for masses.

Use of BI-RADS 3–Probably Benign Category in the American College of Radiology Imaging Network Digital Mammographic Imaging Screening Trial

To determine (a) how often the Breast Imaging Reporting and Data System (BI-RADS) category 3 was used in the American College of Radiology Imaging Network (ACRIN) Digital Mammographic Imaging Screening Trial (DMIST), either at the time of screening mammography or after work-up, (b) how often subjects actually returned for the recommended follow-up examination, and (c) the rate and stages of any malignancies subsequently found in subjects for whom short-term interval follow-up was recommended. This study was approved by the Institutional Review Board at all institutions where subjects were enrolled. All subjects participating in DMIST gave informed consent and the study was HIPAA-compliant. A total of 47,599 DMIST-eligible and evaluable subjects, all of whom consented to undergo both digital and screen-film mammography, were included in this analysis. Cases referred for short-term interval follow-up based on digital, screen-film, or both imaging examinations were determined. Compliance with the recommendations and the final outcome (malignancy diagnosis at biopsy or no malignancy confirmed through follow-up) of each evaluable case were determined. A total of 1114 of the 47,599 (2.34%) subjects had tumors assigned a BI-RADS 3 category and were recommended to undergo short-interval follow-up. In this study, 791 of 1114 (71%) of the subjects were compliant with the recommendation and returned for short-interval follow-up. Of the women who did not return for short-interval follow-up, 70% (226 of 323) did return for their next annual mammography. Among all subjects whose tumors were assigned a BI-RADS 3 category either at screening mammography or after additional work-up, nine of 1114 (0.81%) were found to have cancer. Of the nine biopsy-proved cancers, six were invasive cancers and three were ductal carcinoma in situ stage Tis-T1c. The invasive cancers were all less than 2 cm in size. In DMIST, radiologists used the BI-RADS 3 classification infrequently (2.3% of patients). Tumors assigned a BI-RADS 3 category had a low rate of malignancy. The relatively high rate of noncompliance with short-interval follow-up recommendations (323 of 1114, or 29%) supports prior recommendations that radiologists thoroughly evaluate lesions before placing them in this category.