Effect of implementing digital breast tomosynthesis (DBT) instead of mammography on population screening outcomes including interval cancer rates: Results of the Trento DBT pilot evaluation.

BACKGROUND/AIM: The Trento screening program transitioned to digital breast tomosynthesis (DBT) screening based on evidence that DBT improves breast cancer (BC) detection compared to mammography; an evaluation of the transition to DBT is reported in this pilot study. METHODS: Prospective implementation of DBT screening included women aged ≥50 years who attended the Trento program for biennial screening. DBT screening included DBT acquisitions with synthesized 2D-images. A historical cohort of women who attended the program (January 2013-October 2014) and received digital mammography (DM) provided a comparison group. Independent double-reading (with a third arbitrating read for discordance) was used for DBT and DM screening. Screening outcomes included cancer detection rate (CDR/1000 screens), percentage of screens recalled to assessment (recall%), interval cancer rate (ICR/1000 screens) at 2-year follow-up, and screening sensitivity. Rate ratios (RR) and 95% confidence interval (95%CI) examined outcomes for DBT versus DM screening. RESULTS: From women aged 50-69 years who accepted an invitation to screening (October 2014-October 2016) 46,343 comprised the DBT-screened group: amongst these 402 BCs (includes 50 ductal carcinoma in-situ (DCIS)) were detected (CDR 8.67/1000), whereas 205 BCs (includes 33 DCIS) were detected amongst 37,436 DM screens (CDR 5.48/1000) [RR for CDR:1.58 (1.34-1.87)]. Recall% was lower for DBT (2.55%) than DM (3.21%) [RR:0.79 (0.73-0.86)]. Compared to DM, DBT screening increased CDR for stage I-II BC, for all tumour size and grade categories, and for node-negative BC, but did not increase CDR for DCIS. Estimated ICR for DBT was 1.1/1000 whereas ICR for DM was 1.36/1000 [RR:0.81 (0.55-1.19)]. Screening sensitivity was 88.74% for DBT versus 80.08% for DM [RR:1.11 (0.94-1.31)]. CONCLUSION: DBT significantly improved early-detection measures but did not significantly reduce ICR (relative to DM screening), suggesting that it could add benefit as well as adding over-detection in population BC screening.

Diagnostic Performance of MRI Versus Galactography in Women With Pathologic Nipple Discharge: A Systematic Review and Meta-Analysis.

OBJECTIVE: The objective of our study was to perform a systematic review of the literature of the diagnostic accuracy of MRI compared with galactography in women with pathologic nipple discharge. MATERIALS AND METHODS: A systematic literature search was performed (MEDLINE, Embase, Web of Science) for articles evaluating the diagnostic performance of MRI and galactography in patients with pathologic nipple discharge and with histologic verification or clinical follow-up. Distinction between any abnormality and cancer was made. Two independent readers selected eligible articles published until December 2015. The quality of the studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Data analyses were performed using the bivariate model. RESULTS: Ten articles were analyzed for a total of 921 patients. The study quality was high, with a low risk of bias and low concerns regarding applicability. The pooled sensitivity for any abnormality was significantly higher for MRI, with 92% (95% CI, 85-96%), than for galactography, with 69% (95% CI, 59-78%) (p < 0.001). The pooled specificity was 76% (95% CI, 49-92%) for MRI versus 39% (95% CI, 16-69%) for galactography (p < 0.001). The pooled sensitivity and specificity for cancer detection were calculated for MRI only and were 92% (95% CI, 74-98%) and 97% (95% CI, 80-100%), respectively. CONCLUSION: This meta-analysis shows a higher diagnostic performance of MRI compared with that of galactography in the detection of any kind of lesion in patients with pathologic nipple discharge. Moreover, high sensitivity and very high specificity for cancer by MRI could be confirmed in this clinical setting. If mammography and ultrasound are negative, MRI should be preferred over galactography for further evaluation.

Breast cancer detection using single-reading of breast tomosynthesis (3D-mammography) compared to double-reading of 2D-mammography: Evidence from a population-based trial.

BACKGROUND: Most population breast cancer (BC) screening programs use double-reading of 2D-mammography. We recently reported the screening with tomosynthesis or standard mammography-2 (STORM-2) trial, showing that double-read tomosynthesis (pseudo-3D-mammography) detected more BC than double-read 2D-mammography. In this study, we compare screen-detection measures for single-reading of 3D-mammography with those for double-reading of 2D-mammography, to inform screening practice. METHODS: This is a secondary analysis based on STORM-2 which prospectively compared 3D-mammography and 2D-mammography in sequential screen-readings. Asymptomatic women ≥49 years who attended population-based screening (Trento, 2013-2015) were recruited. Participants recalled at any screen-read from parallel double-reading arms underwent further testing and/or biopsy. Single-reading of 3D-mammography, integrated with acquired or synthetized 2D-mammograms, was compared to double-reading of 2D-mammograhy alone for screen-detection measures: number of detected BCs, cancer detection rate (CDR), number and percentage of false-positive recall (FPR). Paired binary data were compared using McNemar's test. RESULTS: Screening detected 90, including 74 invasive, BCs in 85 of 9672 participants. CDRs for single-reading using integrated 2D/3D-mammography (8.2 per 1000 screens; 95% CI 6.5-10.2) or 2D synthetic/3D-mammography (8.4 per 1000 screens; 95% CI: 6.7-10.4) were significantly higher than CDR for double-reading of 2D-mammography (6.3 per 1000 screens; 95% CI: 4.8-8.1), P<0.001 both comparisons. FPR% for single-read 2D/3D-mammography (2.60%; 95% CI: 2.29-2.94), or single-read 2D synthetic/3D-mammography (2.76%; 95% CI: 2.45-3.11), were significantly lower than FPR% for double-read 2D-mammography (3.42%; 95% CI: 3.07-3.80), P<0.001 and P=0.002 respectively. CONCLUSIONS: Single-reading of 3D-mammography (integrated 2D/3D or 2Dsynthetic/3D) detected more BC, and had lower FPR, compared to current practice of double-reading 2D-mammography alone - these findings have implications for population BC screening programs.

Breast cancer screening with tomosynthesis (3D mammography) with acquired or synthetic 2D mammography compared with 2D mammography alone (STORM-2): a population-based prospective study.

BACKGROUND: Breast tomosynthesis (pseudo-3D mammography) improves breast cancer detection when added to 2D mammography. In this study, we examined whether integrating 3D mammography with either standard 2D mammography acquisitions or with synthetic 2D images (reconstructed from 3D mammography) would detect more cases of breast cancer than 2D mammography alone, to potentially reduce the radiation burden from the combination of 2D plus 3D acquisitions. METHODS: The Screening with Tomosynthesis Or standard Mammography-2 (STORM-2) study was a prospective population-based screening study comparing integrated 3D mammography (dual-acquisition 2D-3D mammography or 2D synthetic-3D mammography) with 2D mammography alone. Asymptomatic women aged 49 years or older who attended population-based screening in Trento, Italy were recruited for the study. All participants underwent digital mammography with 2D and 3D mammography acquisitions, with the use of software that allowed synthetic 2D mammographic images to be reconstructed from 3D acquisitions. Mammography screen-reading was done in two parallel double-readings conducted sequentially for 2D acquisitions followed by integrated acquisitions. Recall based on a positive mammography result was defined as recall at any screen read. Primary outcome measures were a comparison between integrated (2D-3D or 2D synthetic-3D) mammography and 2D mammography alone of the number of cases of screen-detected breast cancer, the cancer detection rate per 1000 screens, the incremental cancer detection rate, and the number and percentage of false-positive recalls. FINDINGS: Between May 31, 2013, and May 29, 2015, 10 255 women were invited to participate, of whom 9672 agreed to participate and were screened. In these 9672 participants (median age 58 years [IQR 53-63]), screening detected 90 cases of breast cancer, including 74 invasive breast cancers, in 85 women (five women had bilateral breast cancer). To account for these bilateral cancers in cancer detection rate estimates, the number of screens used for analysis was 9677. Both 2D-3D mammography (cancer detection rate 8·5 per 1000 screens [82 cancers detected in 9677 screens]; 95% CI 6·7-10·5) and 2D synthetic-3D mammography (8·8 per 1000 [85 in 9677]; 7·0-10·8) had significantly higher rates of breast cancer detection than 2D mammography alone (6·3 per 1000 [61 in 9677], 4·8-8·1; p<0·0001 for both comparisons). The cancer detection rate did not differ significantly between 2D-3D mammography and 2D synthetic-3D mammography (p=0·58). Compared with 2D mammography alone, the incremental cancer detection rate from 2D-3D mammography was 2·2 per 1000 screens (95% CI 1·2-3·3) and that from 2D synthetic-3D mammography was 2·5 per 1000 (1·4-3·8). Compared with the proportion of false-positive recalls from 2D mammography alone (328 of 9587 participants not found to have cancer at assessment) [3·42%; 95% CI 3·07-3·80]), false-positive recall was significantly higher for 2D-3D mammography (381 of 9587 [3·97%; 3·59-4·38], p=0·00063) and for 2D synthetic-3D mammography (427 of 9587 [4·45%; 4·05-4·89], p<0·0001). INTERPRETATION: Integration of 3D mammography (2D-3D or 2D synthetic-3D) detected more cases of breast cancer than 2D mammography alone, but increased the percentage of false-positive recalls in sequential screen-reading. These results should be considered in the context of the trade-off between benefits and harms inherent in population breast cancer screening, including that significantly increased breast cancer detection from integrating 3D mammography into screening has the potential to augment screening benefit and also possibly contribute to overdiagnosis. FUNDING: None.

Accuracy of mammography, digital breast tomosynthesis, ultrasound and MR imaging in preoperative assessment of breast cancer.

AIM: To define the accuracy of digital breast tomosynthesis (DBT) and magnetic resonance imaging (MRI) added to digital mammography (DM) and ultrasound (US) in the preoperative assessment of breast cancer. PATIENTS AND METHODS: We performed a prospective study of 200 consecutive women with histologically-proven breast cancer using the above imaging techniques. Accuracy measurements were estimated using a lesion-by-lesion analysis for unifocal, multifocal/multicentric, bilateral and all carcinomas. We also calculated sensitivity according to breast density. RESULTS: DBT had higher sensitivity than DM (90.7% vs. 85.2%). Combined DM and DBT with US yielded a 97.7% sensitivity; despite high sensitivity of MRI (98.8%), the addition of MRI to combined DM with DBT and US did not significantly improve sensitivity. Overall accuracy did not significantly differ between MRI and DM with DBT and US (92.3% vs. 93.7%). Breast density affected sensitivity of DM and DBT (statistically significant difference for DM), not MRI. CONCLUSION: There is little gain in sensitivity and no gain in overall accuracy, by performing MRI for patients who have been evaluated with DM with DBT and US.

Radiological assessment of breast density by visual classification (BI-RADS) compared to automated volumetric digital software (Quantra): implications for clinical practice.

OBJECTIVE: This study was done to assess breast density on digital mammography and digital breast tomosynthesis according to the visual Breast Imaging Reporting and Data System (BI-RADS) classification, to compare visual assessment with Quantra software for automated density measurement, and to establish the role of the software in clinical practice. MATERIALS AND METHODS: We analysed 200 digital mammograms performed in 2D and 3D modality, 100 of which positive for breast cancer and 100 negative. Radiological density was assessed with the BI-RADS classification; a Quantra density cut-off value was sought on the 2D images only to discriminate between BI-RADS categories 1-2 and BI-RADS 3-4. Breast density was correlated with age, use of hormone therapy, and increased risk of disease. RESULTS: The agreement between the 2D and 3D assessments of BI-RADS density was high (K 0.96). A cut-off value of 21% is that which allows us to best discriminate between BI-RADS categories 1-2 and 3-4. Breast density was negatively correlated to age (r = -0.44) and positively to use of hormone therapy (p = 0.0004). Quantra density was higher in breasts with cancer than in healthy breasts. CONCLUSIONS: There is no clear difference between the visual assessments of density on 2D and 3D images. Use of the automated system requires the adoption of a cut-off value (set at 21%) to effectively discriminate BI-RADS 1-2 and 3-4, and could be useful in clinical practice.

Accuracy of tumour size assessment in the preoperative staging of breast cancer: comparison of digital mammography, tomosynthesis, ultrasound and MRI.

PURPOSE: Accurate measurement of breast tumour size is fundamental for treatment planning. We compared the accuracy of digital mammography (DM), digital breast tomosynthesis (DBT), ultrasound (US) and magnetic resonance imaging (MRI) for the preoperative evaluation of breast cancer size. MATERIALS AND METHODS: We retrospectively reviewed 149 breast cancers in 110 patients who underwent DM, DBT, US and MRI between January 2010 and December 2011, before definitive surgery. The lesions were measured by two radiologists, without knowledge of the final histological examination, considered the gold standard. For each imaging modality, the maximum tumour size was measured to the nearest millimetre; the measurements were considered concordant if they were within ± 5 mm. Pearson's correlation coefficient was calculated for each imaging modality. RESULTS: The median pathological tumour size was 22.3 mm. MRI and DBT had a level of concordance with pathology of 70% and 66%, respectively, which was higher than that of DM (54%). DBT and MRI measurements had a better correlation with pathological tumour size (R:0.89 and R:0.92, respectively) compared to DM (R:0.83) and US (R:0.77). CONCLUSIONS: DBT and MRI are superior to DM and US in the preoperative assessment of breast tumour size. DBT seems to improve the accuracy of DM, although MRI remains the most accurate imaging modality for breast cancer extension.