[Structured screening for sporadic breast cancer]

BACKGROUND

The aim of secondary prevention of breast cancer is to detect the disease at the earliest curable stage and thus to reduce breast cancer-specific mortality. To this end, the nationwide population-based mammography screening program (MSP) was set up in Germany in 2005 in addition to an interdisciplinary prevention project for high-risk groups.

OBJECTIVE

Overview of the current state of the MSP, the upcoming age expansion, and potential further developments.

MATERIAL AND METHODS

Narrative review article with topic-guided literature and data search.

RESULTS

Approximately 50% of the 70,500 new cases of breast cancer that occur each year are related to the age group of the MSP. 10 years after introduction of the MSP, the incidence of advanced breast cancer stages and breast cancer-related mortality of the screening target group have steadily decreased by about one quarter, while no relevant trends were seen in the neighboring age groups at the population level.

CONCLUSION

The MSP has effectively contributed to a reduction of breast cancer mortality. With the expansion of the age groups to 45-75 years, more women have access to structured, quality assured screening. With the use of advanced stratifications and diagnostics as well as artificial intelligence, the MSP could be further optimized.

Digital Breast Tomosynthesis versus Digital Mammography for Detection of Early-Stage Cancers Stratified by Grade: A TOSYMA Subanalysis

Background Breast cancer screening with digital breast tomosynthesis (DBT) plus synthesized mammography (SM) increases invasive tumor detection compared with digital mammography (DM). However, it is not known how the prognostic characteristics of the cancers detected with the two screening approaches differ. Purpose To compare invasive breast cancers detected with DBT plus SM (test arm) versus DM (control arm) screening with regard to tumor stage, histologic grade, patient age, and breast density. Materials and Methods This exploratory subanalysis of the Tomosynthesis plus Synthesized Mammography (TOSYMA) study, which is a multicenter randomized controlled trial embedded in the German mammography screening program, recruited women aged 50-70 years from July 2018 to December 2020. It compared invasive cancer detection rates (iCDRs), rate differences, and odds ratios (ORs) between the arms stratified by Union for International Cancer Control (UICC) stage (I vs II-IV), histologic grade (1 vs 2 or 3), age group (50-59 vs 60-70 years), and Breast Imaging Reporting and Data System categories of breast density (A or B vs C or D). Results In total, 49 462 (median age, 57 years [IQR, 53-62 years]) and 49 669 (median age, 57 years [IQR, 53-62 years]) participants were allocated to DBT plus SM and DM screening, respectively. The iCDR of stage I tumors with DBT plus SM was 51.6 per 10 000 women (255 of 49 462) and with DM it was 30.0 per 10 000 women (149 of 49 669). DBT plus SM depicted more stage I tumors with grade 2 or 3 (166 of 49 462, 33.7 per 10 000 women) than DM (106 of 49 669, 21.3 per 10 000 women; rate difference, +12.3 per 10 000 women [95% CI: 0.3, 24.9]; OR, 1.6 [95% CI: 0.9, 2.7]). DBT plus SM achieved the highest iCDR of stage I tumors with grade 2 or 3 among women aged 60-70 years with dense breasts (41 of 7364, 55.4 per 10 000 women; rate difference, +21.6 per 10 000 women [95% CI: -21.1, 64.3]; OR, 1.6 [95% CI: 0.6, 4.5]). Conclusion DBT plus SM screening appears to lead to higher detection of early-stage invasive breast cancers of grade 2 or 3 than DM screening, with the highest rate among women aged 60-70 years with dense breasts. Clinical trial registration no. NCT03377036 © RSNA, 2023 See also the editorial by Ha and Chang in this issue.

Preoperative breast MRI positively impacts surgical outcomes of needle biopsy-diagnosed pure DCIS: a patient-matched analysis from the MIPA study

OBJECTIVES

To investigate the influence of preoperative breast MRI on mastectomy and reoperation rates in patients with pure ductal carcinoma in situ (DCIS).

METHODS

The MIPA observational study database (7245 patients) was searched for patients aged 18-80 years with pure unilateral DCIS diagnosed at core needle or vacuum-assisted biopsy (CNB/VAB) and planned for primary surgery. Patients who underwent preoperative MRI (MRI group) were matched (1:1) to those who did not receive MRI (noMRI group) according to 8 confounding covariates that drive referral to MRI (age; hormonal status; familial risk; posterior-to-nipple diameter; BI-RADS category; lesion diameter; lesion presentation; surgical planning at conventional imaging). Surgical outcomes were compared between the matched groups with nonparametric statistics after calculating odds ratios (ORs).

RESULTS

Of 1005 women with pure unilateral DCIS at CNB/VAB (507 MRI group, 498 noMRI group), 309 remained in each group after matching. First-line mastectomy rate in the MRI group was 20.1% (62/309 patients, OR 2.03) compared to 11.0% in the noMRI group (34/309 patients, p = 0.003). The reoperation rate was 10.0% in the MRI group (31/309, OR for reoperation 0.40) and 22.0% in the noMRI group (68/309, p < 0.001), with a 2.53 OR of avoiding reoperation in the MRI group. The overall mastectomy rate was 23.3% in the MRI group (72/309, OR 1.40) and 17.8% in the noMRI group (55/309, p = 0.111).

CONCLUSIONS

Compared to those going directly to surgery, patients with pure DCIS at CNB/VAB who underwent preoperative MRI had a higher OR for first-line mastectomy but a substantially lower OR for reoperation.

CLINICAL RELEVANCE STATEMENT

When confounding factors behind MRI referral are accounted for in the comparison of patients with CNB/VAB-diagnosed pure unilateral DCIS, preoperative MRI yields a reduction of reoperations that is more than twice as high as the increase in overall mastectomies.

KEY POINTS

• Confounding factors cause imbalance when investigating the influence of preoperative MRI on surgical outcomes of pure DCIS. • When patient matching is applied to women with pure unilateral DCIS, reoperation rates are significantly reduced in women who underwent preoperative MRI. • The reduction of reoperations brought about by preoperative MRI is more than double the increase in overall mastectomies.

Screening and diagnostic breast MRI: how do they impact surgical treatment? Insights from the MIPA study

OBJECTIVES

To report mastectomy and reoperation rates in women who had breast MRI for screening (S-MRI subgroup) or diagnostic (D-MRI subgroup) purposes, using multivariable analysis for investigating the role of MRI referral/nonreferral and other covariates in driving surgical outcomes.

METHODS

The MIPA observational study enrolled women aged 18-80 years with newly diagnosed breast cancer destined to have surgery as the primary treatment, in 27 centres worldwide. Mastectomy and reoperation rates were compared using non-parametric tests and multivariable analysis.

RESULTS

A total of 5828 patients entered analysis, 2763 (47.4%) did not undergo MRI (noMRI subgroup) and 3065 underwent MRI (52.6%); of the latter, 2441/3065 (79.7%) underwent MRI with preoperative intent (P-MRI subgroup), 510/3065 (16.6%) D-MRI, and 114/3065 S-MRI (3.7%). The reoperation rate was 10.5% for S-MRI, 8.2% for D-MRI, and 8.5% for P-MRI, while it was 11.7% for noMRI (p ≤ 0.023 for comparisons with D-MRI and P-MRI). The overall mastectomy rate (first-line mastectomy plus conversions from conserving surgery to mastectomy) was 39.5% for S-MRI, 36.2% for P-MRI, 24.1% for D-MRI, and 18.0% for noMRI. At multivariable analysis, using noMRI as reference, the odds ratios for overall mastectomy were 2.4 (p < 0.001) for S-MRI, 1.0 (p = 0.957) for D-MRI, and 1.9 (p < 0.001) for P-MRI.

CONCLUSIONS

Patients from the D-MRI subgroup had the lowest overall mastectomy rate (24.1%) among MRI subgroups and the lowest reoperation rate (8.2%) together with P-MRI (8.5%). This analysis offers an insight into how the initial indication for MRI affects the subsequent surgical treatment of breast cancer.

KEY POINTS

• Of 3065 breast MRI examinations, 79.7% were performed with preoperative intent (P-MRI), 16.6% were diagnostic (D-MRI), and 3.7% were screening (S-MRI) examinations. • The D-MRI subgroup had the lowest mastectomy rate (24.1%) among MRI subgroups and the lowest reoperation rate (8.2%) together with P-MRI (8.5%). • The S-MRI subgroup had the highest mastectomy rate (39.5%) which aligns with higher-than-average risk in this subgroup, with a reoperation rate (10.5%) not significantly different to that of all other subgroups.

Breast Density and Breast Cancer Screening with Digital Breast Tomosynthesis: A TOSYMA Trial Subanalysis

Background Digital breast tomosynthesis (DBT) plus synthesized mammography (SM) reduces the diagnostic pitfalls of tissue superimposition, which is a limitation of digital mammography (DM). Purpose To compare the invasive breast cancer detection rate (iCDR) of DBT plus SM versus DM screening for different breast density categories. Materials and Methods An exploratory subanalysis of the TOmosynthesis plus SYnthesized MAmmography (TOSYMA) study, a randomized, controlled, multicenter, parallel-group trial recruited within the German mammography screening program from July 2018 to December 2020. Women aged 50-69 years were randomly assigned (1:1) to DBT plus SM or DM screening examination. Breast density categories A-D were visually assessed according to the Breast Imaging Reporting and Data System Atlas. Exploratory analyses were performed of the iCDR in both study arms and stratified by breast density, and odds ratios and 95% CIs were determined. Results A total of 49 762 women allocated to DBT plus SM and 49 796 allocated to DM (median age, 57 years [IQR, 53-62 years]) were included. In the DM arm, the iCDR was 3.6 per 1000 screening examinations in category A (almost entirely fatty) (16 of 4475 screenings), 4.3 in category B (102 of 23 534 screenings), 6.1 in category C (116 of 19 051 screenings), and 2.3 in category D (extremely dense breasts) (six of 2629 screenings). The iCDR in the DBT plus SM arm was 2.7 per 1000 screening examinations in category A (12 of 4439 screenings), 6.9 in category B (154 of 22 328 screenings), 8.3 in category C (156 of 18 772 screenings), and 8.1 in category D (32 of 3940 screenings). The odds ratio for DM versus DBT plus SM in category D was 3.8 (95% CI: 1.5, 11.1). The invasive cancers detected with DBT plus SM were most often grade 2 tumors; in category C, it was 58% (91 of 156 invasive cancers), and in category D, it was 47% (15 of 32 invasive cancers). Conclusion The TOmosynthesis plus SYnthesized MAmmography trial revealed higher invasive cancer detection rates with digital breast tomosynthesis plus synthesized mammography than digital mammography in dense breasts, relatively and absolutely most marked among women with extremely dense breasts. ClinicalTrials.gov registration no.: NCT03377036 © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Lee and Moy in this issue.

Artificial Intelligence for Indication of Invasive Assessment of Calcifications in Mammography Screening

PURPOSE

Lesion-related evaluation of the diagnostic performance of an individual artificial intelligence (AI) system to assess mamographically detected and histologically proven calcifications.

MATERIALS AND METHODS

This retrospective study included 634 women of one screening unit (July 2012 - June 2018) who completed the invasive assessment of calcifications. For each leasion, the AI-system calculated a score between 0 and 98. Lesions scored > 0 were classified as AI-positive. The performance of the system was evaluated based on its positive predictive value of invasive assessment (PPV3), the false-negative rate and the true-negative rate.

RESULTS

The PPV3 increased across the categories (readers: 4a: 21.2 %, 4b: 57.7 %, 5: 100 %, overall 30.3 %; AI: 4a: 20.8 %, 4b: 57.8 %, 5: 100 %, overall: 30.7 %). The AI system yielded a false-negative rate of 7.2 % (95 %-CI: 4.3 %: 11.4 %) and a true-negative rate of 9.1 % (95 %-CI: 6.6 %; 11.9 %). These rates were highest in category 4a, 12.5 % and 10.4 % retrospectively. The lowest median AI score was observed for benign lesions (61, interquartile range (IQR): 45-74). Invasive cancers yielded the highest median AI score (81, IQR: 64-86). Median AI scores for ductal carcinoma in situ were: 74 (IQR: 63-84) for low grade, 70 (IQR: 52-79) for intermediate grade and 74 (IQR: 66-83) for high grade.

CONCLUSION

At the lowest threshold, the AI system yielded calcification-related PPV3 values that increased across categories, similar as seen in human evaluation. The strongest loss in AI-based breast cancer detection was observed for invasively assessed calcifications with the lowest suspicion of malignancy, yet with a comparable decrease in the false-positive rate. An AI-score based stratification of malignant lesions could not be determined.

KEY POINTS

· The AI-based PPV3 for calcifications is comparable to human assessment.. · AI showed a lower detection performance of screen-positive and screen-negative lesions in category 4a.. · Histological subgroups could not be discriminated by AI scores..

CITATION FORMAT

· Weigel S, Brehl AK, Heindel W et al. Artificial Intelligence for Indication of Invasive Assessment of Calcifications in Mammography Screening. Fortschr Röntgenstr 2023; 195: 38 - 46.

Magnetic resonance imaging before breast cancer surgery: results of an observational multicenter international prospective analysis (MIPA)

OBJECTIVES

Preoperative breast magnetic resonance imaging (MRI) can inform surgical planning but might cause overtreatment by increasing the mastectomy rate. The Multicenter International Prospective Analysis (MIPA) study investigated this controversial issue.

METHODS

This observational study enrolled women aged 18-80 years with biopsy-proven breast cancer, who underwent MRI in addition to conventional imaging (mammography and/or breast ultrasonography) or conventional imaging alone before surgery as routine practice at 27 centers. Exclusion criteria included planned neoadjuvant therapy, pregnancy, personal history of any cancer, and distant metastases.

RESULTS

Of 5896 analyzed patients, 2763 (46.9%) had conventional imaging only (noMRI group), and 3133 (53.1%) underwent MRI that was performed for diagnosis, screening, or unknown purposes in 692/3133 women (22.1%), with preoperative intent in 2441/3133 women (77.9%, MRI group). Patients in the MRI group were younger, had denser breasts, more cancers ≥ 20 mm, and a higher rate of invasive lobular histology than patients who underwent conventional imaging alone (p < 0.001 for all comparisons). Mastectomy was planned based on conventional imaging in 22.4% (MRI group) versus 14.4% (noMRI group) (p < 0.001). The additional planned mastectomy rate in the MRI group was 11.3%. The overall performed first- plus second-line mastectomy rate was 36.3% (MRI group) versus 18.0% (noMRI group) (p < 0.001). In women receiving conserving surgery, MRI group had a significantly lower reoperation rate (8.5% versus 11.7%, p < 0.001).

CONCLUSIONS

Clinicians requested breast MRI for women with a higher a priori probability of receiving mastectomy. MRI was associated with 11.3% more mastectomies, and with 3.2% fewer reoperations in the breast conservation subgroup.

KEY POINTS

• In 19% of patients of the MIPA study, breast MRI was performed for screening or diagnostic purposes. • The current patient selection to preoperative breast MRI implies an 11% increase in mastectomies, counterbalanced by a 3% reduction of the reoperation rate. • Data from the MIPA study can support discussion in tumor boards when preoperative MRI is under consideration and should be shared with patients to achieve informed decision-making.

Simultaneous FAPI PET/MRI Targeting the Fibroblast-Activation Protein for Breast Cancer

Background Integrated PET/MRI is a promising modality for breast assessment. The most frequently used tracer, fluorine 18 (¹⁸F) fluorodeoxyglucose (FDG), is applied for whole-body staging in advanced breast cancer but has limited accuracy in evaluating primary breast lesions. The fibroblast-activation protein (FAP) is abundantly expressed in invasive breast cancer. FAP-directed PET tracers have recently become available, but results in primary breast tumors remain lacking. Purpose To evaluate the use of FAP inhibitor (FAPI) breast PET/MRI in assessing breast lesions and of FAPI whole-body scanning for lymph node (LN) and distant staging using the ligand gallium 68 (⁶⁸Ga)-FAPI-46. Materials and Methods In women with histologically confirmed invasive breast cancer, all primary ⁶⁸Ga-FAPI-46 breast and whole-body PET/MRI and PET/CT examinations conducted at the authors' center between October 2019 and December 2020 were retrospectively analyzed. MRI lesion characteristics and standardized uptake values (SUVs) were quantified with dedicated software. Mann-Whitney U tests were used to compare tumor SUVs across different tumor types. The Pearson correlation coefficient was calculated between SUV and measures of MRI morphologic characteristics. Results Nineteen women (mean age, 49 years ± 9 [standard deviation]) were evaluated-18 to complement initial staging and one for restaging after therapy for distant metastases. Strong tracer accumulation was observed in all 18 untreated primary breast malignancies (mean maximum SUV [SUV_max] = 13.9 [range, 7.9-29.9]; median lesion diameter = 26 mm [range, 9-155 mm]), resulting in clear tumor delineation across different gradings, receptors, and histologic types. All preoperatively verified LN metastases in 13 women showed strong tracer accumulation (mean SUV_max= 12.2 [range, 3.3-22.4]; mean diameter = 21 mm [range, 14-35 mm]). Tracer uptake established or supported extra-axillary LN involvement in seven women and affected therapy decisions in three women. Conclusion This retrospective analysis indicates use of ⁶⁸Ga fibroblast-activation protein inhibitor tracers for breast cancer diagnosis and staging. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Mankoff and Sellmyer in this issue.

Using deep learning to assist readers during the arbitration process: a lesion-based retrospective evaluation of breast cancer screening performance

Objectives

To evaluate if artificial intelligence (AI) can discriminate recalled benign from recalled malignant mammographic screening abnormalities to improve screening performance.

Methods

A total of 2257 full-field digital mammography screening examinations, obtained 2011–2013, of women aged 50–69 years which were recalled for further assessment of 295 malignant out of 305 truly malignant lesions and 2289 benign lesions after independent double-reading with arbitration, were included in this retrospective study. A deep learning AI system was used to obtain a score (0–95) for each recalled lesion, representing the likelihood of breast cancer. The sensitivity on the lesion level and the proportion of women without false-positive ratings (non-FPR) resulting under AI were estimated as a function of the classification cutoff and compared to that of human readers.

Results

Using a cutoff of 1, AI decreased the proportion of women with false-positives from 89.9 to 62.0%, non-FPR 11.1% vs. 38.0% (difference 26.9%, 95% confidence interval 25.1–28.8%; p < .001), preventing 30.1% of reader-induced false-positive recalls, while reducing sensitivity from 96.7 to 91.1% (5.6%, 3.1–8.0%) as compared to human reading. The positive predictive value of recall (PPV-1) increased from 12.8 to 16.5% (3.7%, 3.5–4.0%). In women with mass-related lesions (n = 900), the non-FPR was 14.2% for humans vs. 36.7% for AI (22.4%, 19.8–25.3%) at a sensitivity of 98.5% vs. 97.1% (1.5%, 0–3.5%).

Conclusion

The application of AI during consensus conference might especially help readers to reduce false-positive recalls of masses at the expense of a small sensitivity reduction. Prospective studies are needed to further evaluate the screening benefit of AI in practice.

Key Points

• Integrating the use of artificial intelligence in the arbitration process reduces benign recalls and increases the positive predictive value of recall at the expense of some sensitivity loss.

• Application of the artificial intelligence system to aid the decision to recall a woman seems particularly beneficial for masses, where the system reaches comparable sensitivity to that of the readers, but with considerably reduced false-positives.

• About one-fourth of all recalled malignant lesions are not automatically marked by the system such that their evaluation (AI score) must be retrieved manually by the reader. A thorough reading of screening mammograms by readers to identify suspicious lesions therefore remains mandatory.

[Systematic and quality-assured early diagnosis of sporadic breast cancer : Update on screening effects and scientific studies]

BACKGROUND

A quality-assured mammography screening programme has been available since 2009, nationwide, to all women in Germany between the ages of 50 and 69. The programme is based on the European Guidelines. In this review article the authors summarize the current status of scientific assessments of this national early detection programme for breast cancer and provide an outlook regarding ongoing studies on effectiveness tests and further development.

RESULTS

We expect a decline in mortality rates relating to breast cancer as a result of successfully bringing diagnoses forward and a decrease in advanced breast cancer after a repeated screening. The extent will be shown in the current ZEBra study on mortality evaluation.

CONCLUSION

Potential for a further increase in the effectiveness of the systematic early detection of breast cancer can be identified in four areas: (1) More women should take advantage of the early detection opportunities offered by the medical insurance funds; so far, on average, only about 50% of the women between 50 and 69 who are entitled to a screening examination actually take part in the programme. (2) Entitlement to take part in the programme should be extended to women over 70. (3) The further development of digital mammography towards digital breast tomosynthesis promises to reduce the number of false positive recalls while at the same time increasing sensitivity. (4) There should be scientific studies relating to an extension of screening strategies for the small number of women in the entitlement range who have extremly dense breasts.

Incidence of advanced-stage breast cancer in regular participants of a mammography screening program: a prospective register-based study

BACKGROUND

The European Guidelines for breast cancer screening suggest that the impact of population-based mammography screening programmes (MSP) may be assessed using the relative reduction in the incidence of advanced breast cancer (ABC, that is, stage UICC II and higher) as a surrogate indicator of screening effectiveness.

METHODS

This prospective, population register-based study contained individual data of 1,200,246 women (aged 50-69 years) who attended the initial prevalence screening between 2005 and 2009. Of them, 498,029 women returned for the regular (i.e., within 24 months) first subsequent, and 208,561 for the regular second subsequent incidence screenings. The incidence rate of ABC was calculated for the 24-months period following, but not including, the initial screening by incorporating all interval ABCs and all ABCs detected at the regular first incidence screening; the ABC rate for the second 24-months period was determined in the same way, including ABCs detected in the interval after the first and, respectively, at the second incidence screening. The relative reduction in the ABC incidence was derived by comparing the age-standardized rates in these two periods with an age-standardized reference incidence rate, observed in the target population before the MSP implementation. The strengths and weaknesses of this particular study design were contrasted with a recently published checklist of main methodological problems affecting studies of the effect of MSP on ABC incidence.

RESULTS

The age-standardized ABC incidence rate was 291.6 per 100,000 women for the 24-months period subsequent to the initial screening, and 275.0/100,000 for the 24-months period following the first subsequent screening. Compared to the 2-year incidence of 349.4/100,000 before the start of the MSP, this amounted to a relative reduction of 16.5 and 21.3%, respectively, in the incidence of ABC among regular MSP participants.

CONCLUSIONS

The design employed in this study avoids some of the substantial methodological limitations that compromised previous observational studies. Nevertheless, specific limitations prevail that demand a cautious interpretation of the results. Therefore, the study findings, indicating a reduction in ABC for regular MSP participants, need to be followed with respect to potential impacts on breast cancer mortality rates.

Stratification of Breast Cancer Risk in Terms of the Influence of Age and Mammographic density

PURPOSE

 Analysis of the influence of the singular risk factors age and breast density on the 2-year incidence of breast cancer among participants in the German mammography screening program.

MATERIALS AND METHODS

 The multicenter study includes 111 456 subsequent round digital mammographic screening examinations from four screening units with prospective visual categorization of breast density. Based on detection in screening and during the 2-year interval after negative screening participation (interval cancers), 2-year breast cancer incidences (2 YBCI) (‰) were calculated in the 5-year age groups (5 YAG) of the target group 50-69 years and in the BI-RADS density categories ACR 1-4. Multivariate statistical evaluations were carried out using logistic regression models.

RESULTS

 With an increase in the 5 YAG, the 2 YBCI increased by 5.0 ‰, 6.7 ‰, 8.5 ‰ to 9.7 ‰, and was significantly different among 55-59, 60-64 and 65-69-year-old women compared to the youngest reference group 50-54 years (odds ratio (OR): 1.34; 1.68; and 1.93; p-value < 0.0001). With an increase in density categories 1-4, the 2 YBCI increased from 2.6 ‰, to 5.8 ‰, 9.6 ‰, and 9.7 ‰. The 2 YBCI differed significantly in breast density categories 2, 3, 4 from reference group 1 (OR: 2.17; 3.65; and 3.76; p-value < 0.0001). Only within the two main breast density groups 2 (frequency 44.3 %) and 3 (44.7 %), a significant increase in the 2 YBCI was observed across the 5 YAG (category 2: 3.7-8.9 ‰; category 3: 5.8-11.7 ‰; p-value < 0.001 each). The 2 YBCI was above the median of 7.5 ‰ in women with breast density category 2 and aged 65-69 years, as well as in women with breast density categories 3 and 4 aged 55-69 years. A 2 YBCI below the median was seen in women between 50-54 years regardless of breast density, as well as women in category 1 in all age groups.

CONCLUSION

 Within the main breast density categories 2 and 3 (almost 90 % of participants), incidences increase with age to double. A consistently low incidence is found regardless of breast density at a young screening age and in women with the lowest breast density.

KEY POINTS

  · The risk of breast cancer is modified by age in density categories.. · Women aged 50-54 years have a low risk in all density categories.. · Women in category ACR 1 of any age group have a low risk..

CITATION FORMAT

· Weigel S, Heindel W, Dietz C et al. Stratifizierung des Brustkrebsrisikos hinsichtlich der Einflüsse von Alter und mammografischer Dichte. Fortschr Röntgenstr 2020; 192: 678 - 685.

Consensus Meeting of Breast Imaging: BI-RADS® and Beyond

Organizers of medical educational courses are often confronted with questions that are clinically relevant yet trespassing the frontiers of scientifically proven, evidence-based medicine at the point of care. Therefore, since 2007 organizers of breast teaching courses in German language met biannually to find a consensus in clinically relevant questions that have not been definitely answered by science. The questions were prepared during the 3 months before the meeting according to a structured process and finally agreed upon the day before the consensus meeting. At the consensus meeting, the open questions concerning 2D/3D mammography, breast ultrasound, MR mammography, interventions as well as risk-based imaging of the breast were presented first for electronic anonymized voting, and then the results of the audience were separately displayed from the expert votes. Thereafter, an introductory statement of the moderator was followed by pros/cons of two experts, and subsequently the final voting was performed. With ≥75% of votes of the expert panel, an answer qualified as a consensus statement. Seventeen consensus statements were gained, addressing for instance the use of 2D/3D mammography, breast ultrasound in screening, MR mammography in women with intermediate breast cancer risk, markers for localization of pathologic axillary lymph nodes, and standards in risk-based imaging of the breast. After the evaluation, comments from the experts on each field were gathered supplementarily. Methodology, transparency, and soundness of statements achieve a unique yield for all course organizers and provide solid pathways for decision making in breast imaging.

Breast cancer risk in BRCA1/2 mutation carriers and noncarriers under prospective intensified surveillance

Comparably little is known about breast cancer (BC) risks in women from families tested negative for BRCA1/2 mutations despite an indicative family history, as opposed to BRCA1/2 mutation carriers. We determined the age-dependent risks of first and contralateral breast cancer (FBC, CBC) both in noncarriers and carriers of BRCA1/2 mutations, who participated in an intensified breast imaging surveillance program. The study was conducted between January 1, 2005, and September 30, 2017, at 12 university centers of the German Consortium for Hereditary Breast and Ovarian Cancer. Two cohorts were prospectively followed up for incident FBC (n = 4,380; 16,398 person-years [PY], median baseline age: 39 years) and CBC (n = 2,993; 10,090 PY, median baseline age: 42 years). Cumulative FBC risk at age 60 was 61.8% (95% CI 52.8-70.9%) for BRCA1 mutation carriers, 43.2% (95% CI 32.1-56.3%) for BRCA2 mutation carriers and 15.7% (95% CI 11.9-20.4%) for noncarriers. FBC risks were significantly higher than in the general population, with incidence rate ratios of 23.9 (95% CI 18.9-29.8) for BRCA1 mutation carriers, 13.5 (95% CI 9.2-19.1) for BRCA2 mutation carriers and 4.9 (95% CI 3.8-6.3) for BRCA1/2 noncarriers. Cumulative CBC risk 10 years after FBC was 25.1% (95% CI 19.6-31.9%) for BRCA1 mutation carriers, 6.6% (95% CI 3.4-12.5%) for BRCA2 mutation carriers and 3.6% (95% CI 2.2-5.7%) for noncarriers. CBC risk in noncarriers was similar to women with unilateral BC from the general population. Further studies are needed to confirm whether less intensified surveillance is justified in women from BRCA1/2 negative families with elevated risk.

Higher Detection Rates of Biologically Aggressive Breast Cancers in Mammography Screening than in the Biennial Interval

PURPOSE

 Assessment of age group-dependent detection rates of invasive breast cancers among participants in mammography screening including the interval, classified into immunohistochemical subtypes indicating the intrinsic tumor aggressiveness.

MATERIALS UND METHODS

 The target population comprises women aged 50 - 69 years. All invasive breast cancers diagnosed in one screening (sc) unit during the implementation phase 1/2006 - 12/2010 or identified by the cancer registry during the biennial interval (iv) were categorized based on hormonal-receptor status (HR) and Her2-expression (Her2) into the following subtypes: a) HR+ Her2-, b) HR+ Her2 +, c) HR- Her2 + or d) HR- Her2- (triple-negative); Her2 + and triple-negative types were defined as aggressive. The calculated detection rates (DR, ‰) were based on 53 375 sc-examinations and for the interval on 52 887 sc-negative examinations.

RESULTS

 The DRs of all subtypes were higher in screening versus the interval: (a) 4.95 ‰ (n = 264) vs. 1.00 ‰ (n = 53); b) 0.92 ‰ (n = 49) vs. 0.25 ‰ (n = 13); c) 0.36 ‰ (n = 19) vs. 0.06 ‰ (n = 3); d) 0.39 ‰ (n = 21) vs. 0.19 ‰ (n = 10). 77.4 ‰ (89/115) of all aggressive breast cancers including the following 2-year interval were diagnosed by screening. The sum of the DR of aggressive cancers was 1.67 ‰ in screening and 0.49 ‰ in the interval; the corresponding DRs for women aged 60 - 69 years [sc: 2.24 ‰ (51/22 814), iv: 0.58 ‰ (13/22 536)] were higher than among women aged 50 - 59 years [sc: 1.24 ‰ (38/30 561), iv: 0.43 ‰ (13/30 351)].

CONCLUSION

 Screening has the potential for earlier diagnosis of aggressive tumor types as its detection rate is about three-fold higher compared to the interval. Within the target group, participants aged 60 - 69 years are at risk based on absolute numbers. They show a nearly two-fold higher detection rate of Her2-positive or triple-negative tumors compared to the age group 50 - 59 years.

KEY POINTS

  · Her2-positive and triple-negative detection rates are higher in screening than in the interval.. · 77 % of aggressive subtypes are diagnosed by screening, 23 % during the 2-year interval.. · The detection rate is highest among women aged 60 - 69 years in screening..

CITATION FORMAT

· Prange A, Bokhof B, Polzer P et al. Higher Detection Rates of Biologically Aggressive Breast Cancers in Mammography Screening than in the Biennial Interval. Fortschr Röntgenstr 2019; 191: 130 - 136.

Digital breast tomosynthesis plus synthesised images versus standard full-field digital mammography in population-based screening (TOSYMA): protocol of a randomised controlled trial

INTRODUCTION

Development of digital breast tomosynthesis (DBT) provides a technology that generates three-dimensional data sets, thus reducing the pitfalls of overlapping breast tissue. Observational studies suggest that the combination of two-dimensional (2D) digital mammography and DBT increases diagnostic accuracy. However, because of duplicate exposure, this comes at the cost of an augmented radiation dose. This undesired adverse impact can be avoided by using synthesised 2D images reconstructed from the DBT data (s2D).We designed a diagnostic superiority trial on a high level of evidence with the aim of providing a comparison of screening efficacy parameters resulting from DBT+s2D versus the current screening standard 2D full-field digital mammography (FFDM) in a multicentre and multivendor setting on the basis of the quality-controlled, population-based, biennial mammography screening programme in Germany.

METHODS AND ANALYSIS

80 000 women in the eligible age 50-69 years attending the routine mammography screening programme and willing to participate in the TOSYMA trial will be assigned by 1:1 randomisation to either the intervention arm (DBT+s2D) or the control arm (FFDM) during a 12-month recruitment period in screening units of North Rhine-Westphalia and Lower Saxony. State cancer registries will provide the follow-up of interval cancers.Primary endpoints are the detection rate of invasive breast cancers at screening examination and the cumulative incidence of interval cancers in the 2 years after a negative examination. Secondary endpoints are the detection rate of ductal carcinoma in situ and of tumour size T1, the recall rate for assessment, the positive predictive value of recall and the cumulative 12-month incidence of interval cancers. An adaptive statistical design with one interim analysis provides the option to modify the design.

ETHICS AND DISSEMINATION

This protocol has been approved by the local medical ethical committee (2016-132-f-S). Results will be submitted to international peer-reviewed journals.

TRIAL REGISTRATION

NCT03377036; Pre-results.

Multi-color polymer pen lithography for oligonucleotide arrays

Multi-color patterning by polymer pen lithography (PPL) was used to fabricate covalently immobilized fluorophore and oligonucleotide arrays with up to five different components. These can easily be translated for presentation of multiple protein types to a single cell.

Digital Mammography Screening: Does Age Influence the Detection Rates of Low-, Intermediate-, and High-Grade Ductal Carcinoma in Situ?

PURPOSE

To investigate the association between age at screening and detection rates for ductal carcinoma in situ (DCIS) separately for different nuclear grades after introduction of a population-based digital mammography screening program.

MATERIALS AND METHODS

The retrospective study was approved by the ethics board and did not require informed consent. In 733 905 women aged 50-69 years who participated in a screening program for the first time in 2005-2008 (baseline examinations were performed with digital mammography), DCIS detection rates were determined for 5-year age groups (detection rates per 1000 women screened) to distinguish high-, intermediate-, and low-grade DCIS. Multivariable logistic regression was used to compare detection rates between age groups by adjusting for screening units (P < .05).

RESULTS

There were 989 graded DCIS diagnoses among 733 905 women (detection rate, 1.35‰): 419 diagnoses of high-grade DCIS (detection rate, 0.57‰), 388 diagnoses of intermediate-grade DCIS (detection rate, 0.53‰), and 182 diagnoses of low-grade DCIS (detection rate, 0.25‰). Detection rate for types of DCIS combined increased significantly across age groups (50-54 years, detection rate of 1.15‰ [254 of 220 985 women]; 55-59 years, detection rate of 1.23‰ [218 of 177 782 women]; 60-64 years, detection rate of 1.34‰ [201 of 150 415 women]; and 65-69 years, detection rate of 1.71‰ [316 of 184 723 women]; P < .001). Of note, the detection rate for high-grade DCIS showed a significant increase with age (odds ratio, 1.18 per 5-year age group; P < .0001). The increase was lower for intermediate-grade DCIS (odds ratio, 1.11; P = .016) and not significant for low-grade DCIS (P = .10).

CONCLUSION

Total DCIS detection rates increase with age, mostly because of an increase in high- and intermediate-grade DCIS, which are precursor lesions that carry a higher risk for transition to more aggressive invasive breast cancer than low-grade DCIS.

Reduction of Advanced Breast Cancer Stages at Subsequent Participation in Mammography Screening

PURPOSE

The decline in advanced breast cancer stages is presumably the most relevant surrogate parameter in mammography screening. It represents the last step in the causal cascade that is expected to affect breast cancer-related mortality. To assess the effectiveness of population-based screening, we analyzed the 2-year incidence rates of advanced breast cancers between women participating in the initial and in the first subsequent round.

MATERIALS AND METHODS

The study included data from 19,563 initial and 18,034 subsequent examinations of one digital screening unit (2008 - 2010). Data on tumor stages, detected by screening or within the following interval of two years (2-year incidence), were provided by the epidemiological cancer registry. Rates of all and combined UICC stages 2, 3 and 4 (advanced stages) were reported for a two-year period. Proportions were tested for significance by using chi-square tests (p < 0.001).

RESULTS

The 2-year incidence rate of all stages was significantly lower in participants in subsequent screening than in initial screening (0.85 vs. 1.29 per 100 women (%); p < 0.0001). A significantly lower 2-year incidence of advanced stages was observed for subsequent screening compared to initial screening (0.26 % vs. 0.48 %; p = 0.0007). Among women aged 50 to 59 years, the incidence of advanced stages was less clearly different (0.21 % vs. 0.35 %; p = 0.07) than in women aged 60 to 69 years (0.31 % vs. 0.70 %; p = 0.0008).

CONCLUSION

During the change from prevalent to incident phase mammography screening, a program impact is seen by a lower 2-year incidence of advanced breast cancers within subsequent compared to initial participants, predominately in women aged 60 to 69 years.

KEY POINTS

• The incidence of advanced tumor stages represents the most relevant surrogate parameter for screening effectiveness. • For the first time the 2-year incidence of advanced breast cancer stages after subsequent mammography screening was analyzed. • We observed a significant effect of screening on the 2-year incidence of advanced stages, predominately in the age group 60 to 69 years.

Validation of methods for the detection and quantification of engineered nanoparticles in food

The potential impact of nanomaterials on the environment and on human health has already triggered legislation requiring labelling of products containing nanoparticles. However, so far, no validated analytical methods for the implementation of this legislation exist. This paper outlines a generic approach for the validation of methods for detection and quantification of nanoparticles in food samples. It proposes validation of identity, selectivity, precision, working range, limit of detection and robustness, bearing in mind that each "result" must include information about the chemical identity, particle size and mass or particle number concentration. This has an impact on testing for selectivity and trueness, which also must take these aspects into consideration. Selectivity must not only be tested against matrix constituents and other nanoparticles, but it shall also be tested whether the methods apply equally well to particles of different suppliers. In trueness testing, information whether the particle size distribution has changed during analysis is required. Results are largely expected to follow normal distributions due to the expected high number of particles. An approach of estimating measurement uncertainties from the validation data is given.