Performance comparison of single-view digital breast tomosynthesis plus single-view digital mammography with two-view digital mammography

Objective

To determine the performance of combined single-view mediolateral oblique (MLO) digital breast tomosynthesis (DBT) plus single-view cranio-caudal (CC) mammography (MX) compared with that of standard two-view digital mammography.

Methods

A multi-reader multi-case (MRMC) receiver-operating characteristic (ROC) study was conducted, involving six breast radiologists. Two hundred fifty patients underwent bilateral MX and DBT imaging. MX and DBT images with the adjunct of the CC-MX view from 469 breasts were evaluated and rated independently by six readers. Differences in mean areas under the ROC curves (AUCs), mean sensitivity and mean specificity were analysed by analysis of variance (ANOVA) to assess clinical performance.

Results

The combined technique was found to be non-inferior to standard two-view mammography (MX_(CC+MLO)) in mean AUC (difference: +0.021;95 % LCL = ?0.011), but was not statistically significant for superiority (P?=?0.197). The combined technique had equivalent sensitivity to standard mammography (76.2 % vs. 72.8 %, P?=?0.269) and equivalent specificity (84.9 % vs. 83.0 %, P?=?0.130). Specificity for benign lesions was significantly higher with the combination of techniques versus mammography (45.6 % vs. 36.8 %, P?=?0.002).

Conclusion

In this enriched study population, the combination of single-view MLO tomosynthesis plus single-view CC mammography was non-inferior to that of standard two-view digital mammography in terms of ROC curve area, sensitivity and specificity.

Key Points

? Breast tomosynthesis (DBT) has emerged as a valuable adjunct to mammography (MX). ? Combination DBT/MX demonstrated non-inferior clinical performance to standard two-view MX. ? Combination DBT/MX was superior to two-view MX in recognising benign lesions. ? Combination DBT/MX reduced variability compared with two-view MX.     

全视野数字乳腺摄影结合乳腺数字体层合成摄影的辐射剂量与压迫厚度及乳房密度的相关性研究

目的 对比分析乳腺数字体层摄影及全数字乳腺摄影（DBT/FFDM）模式平均腺体剂量（AGD）与乳房密度、压迫厚度的关系,探讨不同类型（厚度和密度）乳房在具体情况下摄影方式的优化选择与应用。方法 回顾性分析229例乳房Combo （DBT+FFDM）临床资料,分别收集记录双乳正位（CC）及内外斜位（MLO）压迫厚度、AGD、kVp和乳房量化密度（Q_abd）类型,分析DBT/FFDM模式下压迫厚度、密度与AGD之间的关系。结果 DBT/FFDM模式AGD与压迫厚度（CC位：r=0.55、0.53,P<0.001;MLO位：r=0.62、0.48,P<0.001）、乳房密度（CC位：r=0.36、0.39,P<0.001;MLO位：r=0.16、0.30,P<0.001）正相关;DBT模式AGD组间差异小,FFDM模式AGD组间差异大（厚度分组CC位：F=35.29、31.32,P<0.005;MLO位：F=44.83、27.02,P<0.005;Q_abd分类CC位：F=18.68、19.76,P<0.005;MLO位：F=4.58、10.52,P<0.005）;Q_abd分类高的乳房平均压迫厚度较低（CC位：F=16.28,P<0.005;MLO位：F=17.81,P<0.005）;同时考虑压迫厚度与乳房密度交互作用影响,仅在MLO位DM模式对AGD有交互作用（F=3.16,P=0.005）。结论 DBT/FFDM两种模式剂量累积可能增加辐射风险;乳腺摄影优先采用单视图CC/MLO-DBT或CC/MLO-（DBT+FFDM）+单视图MLO/CC-FFDM模式,在减低辐射剂量风险方面有积极作用。     

Combination of one-view digital breast tomosynthesis with one-view digital mammography versus standard two-view digital mammography: per lesion analysis

Objective

To evaluate the clinical value of combining one-view mammography (cranio-caudal, CC) with the complementary view tomosynthesis (mediolateral-oblique, MLO) in comparison to standard two-view mammography (MX) in terms of both lesion detection and characterization.

Methods

A free-response receiver operating characteristic (FROC) experiment was conducted independently by six breast radiologists, obtaining data from 463 breasts of 250 patients. Differences in mean lesion detection fraction (LDF) and mean lesion characterization fraction (LCF) were analysed by analysis of variance (ANOVA) to compare clinical performance of the combination of techniques to standard two-view digital mammography.

Results

The 463 cases (breasts) reviewed included 258 with one to three lesions each, and 205 with no lesions. The 258 cases with lesions included 77 cancers in 68 breasts and 271 benign lesions to give a total of 348 proven lesions. The combination, DBT_(MLO)+MX_(CC), was superior to MX (CC+MLO) in both lesion detection (LDF) and lesion characterization (LCF) overall and for benign lesions. DBT_(MLO)+MX_(CC) was non-inferior to two-view MX for malignant lesions.

Conclusions

This study shows that readers’ capabilities in detecting and characterizing breast lesions are improved by combining single-view digital breast tomosynthesis and single-view mammography compared to two-view digital mammography.

Key Points

? Digital breast tomosynthesis is becoming adopted as an adjunct to mammography (MX) ? DBT _(MLO) +MX _(CC) is superior to MX _(CC+MLO) in lesion detection (overall and benign lesions) ? DBT _(MLO) +MX _(CC) is non-inferior to MX _(CC+MLO) in cancer detection ? DBT _(MLO) +MX _(CC) is superior to MX _(CC+MLO) in lesion characterization (overall and benign lesions) ? DBT _(MLO) +MX _(CC) is non-inferior to MX _(CC+MLO) in characterization of malignant lesions     

DBT联合FFDM、FFDM对乳腺疾病诊断效能比较

浸润性导管癌(invasive ductal carcinoma,IDC)为最常见的乳腺癌之一,浸润性生长,具有明显转移倾向.与乳腺超声、乳腺CT及MR相比,乳腺X线摄影在对乳腺内病灶的钙化数量、形态、大小及密度的显示方面具有明显优势;数字化乳腺摄影的出现使乳腺癌的早期检出率大大提高[1].而一些乳腺疾病诸如腺病、炎症等在X线摄影上常与恶性病变难以分辨.     

Radiation dose with digital breast tomosynthesis compared to digital mammography: per-view analysis

Objectives

To compare radiation dose delivered by digital mammography (FFDM) and breast tomosynthesis (DBT) for a single view.

Methods

4,780 FFDM and 4,798 DBT images from 1,208 women enrolled in a screening trial were used to ground dose comparison. Raw images were processed by an automatic software to determine volumetric breast density (VBD) and were used together with exposure data to compute the mean glandular dose (MGD) according to Dance’s model. DBT and FFDM were compared in terms of operation of the automatic exposure control (AEC) and MGD level.

Results

Statistically significant differences were found between FFDM and DBT MGDs for all views (CC: MGD_FFDM=1.366 mGy, MGD_DBT=1.858 mGy; p<0.0001; MLO: MGD_FFDM=1.374 mGy, MGD_DBT=1.877 mGy; p<0.0001). Considering the 4,768 paired views, Bland-Altman analysis showed that the average increase of DBT dose compared to FFDM is 38 %, and a range between 0 % and 75 %.

Conclusions

Our findings show a modest increase of radiation dose to the breast by tomosynthesis compared to FFDM. Given the emerging role of DBT, its use in conjunction with synthetic 2D images should not be deterred by concerns regarding radiation burden, and should draw on evidence of potential clinical benefit.

Key Points

? Most studies compared tomosynthesis in combination with mammography vs. mammography alone. ? There is some concern about the dose increase with tomosynthesis. ? Clinical data show a small increase in radiation dose with tomosynthesis. ? Synthetic 2D images from tomosynthesis at zero dose reduce potential harm. ? The small dose increase should not be a barrier to use of tomosynthesis.

     

Comparative study between breast tomosynthesis and classic digital mammography in the evaluation of different breast lesions

Objective

To evaluate the impact of adding 3D Tomosynthesis to Full Field Digital Mammography (FFDM) in the detection and diagnosis of breast lesions.

Subjects and methods

The study included 166 mammograms with indeterminate findings selected from 1600 mammograms. They were classified into two groups: group 1 ‘Diagnostic mammograms’ of symptomatic women and group 2 ‘Screening mammograms’. Dense breasts assigned as ACR3 and ACR4 presented 69% (n = 114/166) of the studied cases. FFDM and 3D tomosynthesis examination was done and imaging findings were evaluated before and after the use of 3D tomosynthesis images.

Results

Both modalities were compared regarding detection and diagnosis, each individually assessed, using the Pearson Chi Square tests. Detection (P value: 0.006) and diagnosis (P value: 0.048) of breast lesions dramatically improved when 3D tomosynthesis images were considered in the evaluation. The sensitivity, specificity, and accuracy of digital mammography was 60%, 20.7% and 48% have significantly enhanced on applying tomosynthesis to be 94.5%, 74% and 89.7%.

Conclusion

Three-dimensional tomosynthesis significantly enhanced the detection and characterization of breast lesions on digital mammography especially in the context of dense breast parenchyma (ACR 3&4).     

Comparison between two-dimensional synthetic mammography reconstructed from digital breast tomosynthesis and full-field digital mammography for the detection of T1 breast cancer

Objective

To evaluate the interpretative performance of two-dimensional (2D) synthetic mammography (SM) reconstructed from digital breast tomosynthesis (DBT) in the detection of T1-stage invasive breast cancers, compared to 2D full-field digital mammography (FFDM).

Methods

This retrospective study enrolled 214 patients. For each patient, FFDM and DBT were performed between January and June 2013, and SM was reconstructed from DBT data. Three radiologists interpreted images and recorded visibility scores and morphologies of cancers. Diagnostic performances of SM and FFDM were compared. Percentages of detected cancers and visibility scores were compared for tumour size, and presence of calcifications for each observer.

Results

Observer sensitivity showed no difference for detection with SM and FFDM (P?>?0.05). One observer showed a higher specificity (P?=?0.02) and higher positive predictive value with SM (95 % CI 0.6–16.4), but the differences in the corresponding values between SM and FFDM for the other observers were not statistically significant. In subgroup analyses according to tumour size and presence of calcifications, percentages of detected cancers and visibility scores were not significantly different.

Conclusions

Diagnostic performances of SM and FFDM are comparable for detecting T1-stage breast cancers. Therefore, our results indicate that SM may eliminate the need for additional FFDM during DBT-based imaging.

Key Points

? DBT plus FFDM increases radiation dose compared to FFDM alone.? Detecting T1-stage cancers with only SM is comparable to detection with FFDM.? Two-dimensional SM may replace dose-requiring FFDM in DBT-based imaging.

     

Estimation of percentage breast tissue density: comparison between digital mammography (2D full field digital mammography) and digital breast tomosynthesis according to different BI-RADS categories

Objective:

To compare breast density estimated from two-dimensional full-field digital mammography (2D FFDM) and from digital breast tomosynthesis (DBT) according to different Breast Imaging–Reporting and Data System (BI-RADS) categories, using automated software.

Methods:

Institutional review board approval and written informed patient consent were obtained. DBT and 2D FFDM were performed in the same patients to allow within-patient comparison. A total of 160 consecutive patients (mean age: 50±14 years; mean body mass index: 22±3) were included to create paired data sets of 40 patients for each BI-RADS category. Automatic software (MedDensity^©, developed by Giulio Tagliafico) was used to compare the percentage breast density between DBT and 2D FFDM. The estimated breast percentage density obtained using DBT and 2D FFDM was examined for correlation with the radiologists'' visual BI-RADS density classification.

Results:

The 2D FFDM differed from DBT by 16.0% in BI-RADS Category 1, by 11.9% in Category 2, by 3.5% in Category 3 and by 18.1% in Category 4. These differences were highly significant (p<0.0001). There was a good correlation between the BI-RADS categories and the density evaluated using 2D FFDM and DBT (r=0.56, p<0.01 and r=0.48, p<0.01, respectively).

Conclusion:

Using DBT, breast density values were lower than those obtained using 2D FFDM, with a non-linear relationship across the BI-RADS categories. These data are relevant for clinical practice and research studies using density in determining the risk.

Advances in knowledge:

On DBT, breast density values were lower than with 2D FFDM, with a non-linear relationship across the classical BI-RADS categories.To tailor screening and diagnosis protocols, it is important to identify females with an increased risk of breast cancer [1–3]. It has been estimated that females with dense breasts (breast densities of >75%) have 4–6 times higher risk of breast cancer than females with low breast densities [4] and that breast density is increasingly recognised as an independent determinant of breast cancer risk and possibly in prognosis [5]. Assessment of breast density is becoming crucial in epidemiological studies, including the estimation of breast cancer risk and assessing breast density-related risk over time, radiation dose monitoring and monitoring drug-related response [6,7].Different methods and classifications have been reported to assess breast density: the Tabar classification [8], Wolfe''s parenchymal patterns [9], and both semi-quantitative and quantitative computer-aided techniques [10–16]. The Breast Imaging–Reporting and Data System (BI-RADS) classification, considered as the additional quantitative scheme, is routinely used in the USA and was introduced to standardise reporting. Initially, it was based on four qualitative categories but an additional quantitative scheme was added in 2003, based on the extent of fibroglandular tissue [17]. Mammographic breast density estimation may be limited by the two-dimensional (2D) nature of the imaging technique, whereas a three-dimensional (3D) imaging modality, such as digital breast tomosynthesis (DBT), reduces the appearance of the overlapping parenchymal tissue and may therefore influence or alter density assessments [13,14]. In DBT, high-spatial-resolution tomographic images of the breast are reconstructed from multiple low-dose projection images acquired within a limited range of X-ray tube angles [15]. It has been demonstrated in a few studies that the automated estimation of breast density eliminates subjectivity between comparisons of full-field digital mammography (2D FFDM) and DBT and is more reproducible than a quantitative BI-RADS evaluation [14,16]. However, previous research mainly considered patients with relatively high breast density, with the possibility of the results not being applicable across all density categories and showing whether published percentage breast density differences between 2D FFDM and DBT apply to less dense or non-dense breasts. The purpose of our study was to compare the breast tissue density estimated using 2D FFDM and DBT among patients in a balanced data set of the four BI-RADS categories, using fully automated software.     

Mammographic density estimation: one-to-one comparison of digital mammography and digital breast tomosynthesis using fully automated software

Objective

To compare breast density on digital mammography and digital breast tomosynthesis using fully automated software.

Methods

Following institutional approval and written informed consent from all participating women, both digital breast tomosynthesis (DBT) and full-field digital mammography (FFDM) were obtained. Breast percentage density was calculated with software on DBT and FFDM.

Results

Fifty consecutive patients (mean age, 51?years; range, 35–83?years) underwent both FFDM and DBT. Using a method based on the integral curve, breast density showed higher results on FFDM (68.1?±?12.1 for FFDM and 51.9?±?6.5 for DBT). FFDM overestimated breast density in 16.2% (P?P?r?=?0.54, P?r?=?0.44, P?Conclusion Breast density appeared to be significantly underestimated on digital breast tomosynthesis.

Key Points

• Breast density is considered to be an independent risk factor for cancer
• Density can be assessed on full-field digital mammography and digital breast tomosynthesis
• Objective automated estimation of breast density eliminates subjectivity
• Automated estimation is more accurate than BI-RADS quantitative evaluation
• Breast density may be significantly underestimated on digital breast tomosynthesis

     

乳腺数字化断层摄影分析乳腺实质结构评估罹患乳腺癌风险:与乳腺数字化摄影比较

目的乳腺密度百分比(PD)是已被确认的罹患乳腺癌的风险因子,本研究目的是在筛查人群中评估数字化乳腺断层摄影(DBT)与数字化乳腺摄影显示的乳腺实质结构特征与PD的相关性。材料与方法本研究经专业委员会核准,受试者均签署书面知情同意书。回顾性分析2007年7月—2008年3月进行的一项经专业委员会批准的DBT筛查     

Effects on short-term quality of life of vacuum-assisted breast biopsy: comparison between digital breast tomosynthesis and digital mammography

Objective:

To compare the effects of digital breast tomosynthesis (DBT)-guided and digital mammography (MMx)-guided vacuum-assisted breast biopsy (VABB) on short-term quality of life (QoL).

Methods:

From November 2014 through March 2015, females undergoing VABB in an academic medical centre participated in a survey after biopsy. VABB was performed under DBT (Group 1) or MMx guidance (Group 2). Biopsy experience was assessed with a modified testing morbidities index (TMI). 10 attributes were assessed: six related to the procedures (pain or discomfort before and during testing, fear or anxiety before and during testing, physical and mental function after testing) and four not related to the procedures (familiarity for cancer and clinical history, embarrassment during testing and overall satisfaction). Non-parametric standard statistics were used to compare data of Group 1 and data of Group 2.

Results:

A total of 90 females (mean age, 55.8 years; range, 40–87 years) were enrolled: 45 underwent DBT-VABB and 45 MMx-VABB. The sum of the 6 of 10 items related to the procedures was significantly worse for DBT (p < 0.02), but no differences were observed for the single items. The median value for DBT-VABB and MMx-VABB was 95.2 and 90.1, respectively (p < 0.02). The 4 of 10 TMI items not related to the procedures did not differ significantly between the two groups. Four females fainted during DBT-VABB and three females during MMx-VABB; all of these patients underwent VABB procedures in sitting position.

Conclusion:

Females in the DBT-VABB study group have a decreased short-term QoL compared with the MMx-VABB group. DBT-VABBs were less tolerated than MMx-VABBs.

Advances in knowledge:

DBT-VABB was less tolerated than MMx-VABB. Females in the DBT-VABB study group had a decreased short-term QoL compared with the MMx-VABB group. Overall satisfaction was similar for both procedures.     

Conspicuity of breast cancer according to histopathological type and breast density when imaged by full-field digital mammography compared with screen-film mammography

Objectives  

To compare the conspicuity of different histopathological types of breast cancer according to breast density and mammographic imaging in patients with screen-detected breast cancers undergoing both full-field digital mammography (FFDM) and screen-film mammography (SFM) in the United Kingdom National Health Service Breast Screening Programme (NHSBSP).     

不同乳腺密度全野数字化乳腺X线摄影与屏-片乳腺摄影对不同组织病理学乳腺癌显示清晰度的对照研究

目的英国国家健康服务乳腺普查项目(NHSBSP)中,对普查探查到的乳腺癌病人行全野数字化乳腺X线摄影(FFDM)和屏-片乳腺摄影(SFM),比较两种方法在不同乳腺     

Breast tomosynthesis and digital mammography: a comparison of breast cancer visibility and BIRADS classification in a population of cancers with subtle mammographic findings

The main purpose was to compare breast cancer visibility in one-view breast tomosynthesis (BT) to cancer visibility in one- or two-view digital mammography (DM). Thirty-six patients were selected on the basis of subtle signs of breast cancer on DM. One-view BT was performed with the same compression angle as the DM image in which the finding was least/not visible. On BT, 25 projections images were acquired over an angular range of 50 degrees, with double the dose of one-view DM. Two expert breast imagers classified one- and two-view DM, and BT findings for cancer visibility and BIRADS cancer probability in a non-blinded consensus study. Forty breast cancers were found in 37 breasts. The cancers were rated more visible on BT compared to one-view and two-view DM in 22 and 11 cases, respectively, (p < 0.01 for both comparisons). Comparing one-view DM to one-view BT, 21 patients were upgraded on BIRADS classification (p < 0.01). Comparing two-view DM to one-view BT, 12 patients were upgraded on BIRADS classification (p < 0.01). The results indicate that the cancer visibility on BT is superior to DM, which suggests that BT may have a higher sensitivity for breast cancer detection.     

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.