Routine Breast Magnetic Resonance Imaging Research Articles

Quantification of breast biopsy clip marker artifact on routine breast MRI sequences: a phantom study

BackgroundTo investigate the artifact sizes of four common breast clip-markers on a standard breast magnetic resonance imaging (MRI) protocol in an in vitro phantom model.MethodsUsing 1.5-T and 3-T whole-body scanners with an 18-channel breast coil, artifact dimensions of four breast biopsy markers in an agarose-gel phantom were measured by two readers on images obtained with the following sequences: T2-weighted fast spin-echo short inversion time fat-suppressed inversion-recovery with magnitude reconstruction (T2-TIRM); T1-weighted spoiled gradient-echo with fat suppression (T1_FL3D), routinely used for dynamic contrast-enhanced imaging; diffusion-weighted imaging (DWI), including a readout segmented echo-planar imaging (RESOLVE-DWI) and echo-planar imaging sequence (EPI-DWI). After outlining the artifacts by freehand regions of interest, sagittal and lateral diameters in axial images were measured.ResultsInterreader agreement for artifact size quantification was high, depending on the sequence (80.4–94.8%). Overall, the size, shape, and appearance of artifacts depended on clip type and MRI sequence. The artifact size ranged from 5.7 × 8.5 mm2 to 13.4 × 17.7 mm2 at 1.5 T and from 6.6 × 8.2 mm2 to 17.7 × 20.7 mm2 at 3 T. Clip artifacts were largest on EPI-DWI and RESOLVE-DWI (p ≤ 0.016). In three out of four clips, T2-TIRM showed the smallest artifact (p ≤ 0.002), while in one clip the artifact was smallest on T1_FL3D (p = 0.026). With the exception of one clip in the RESOLVE sequence, all clips showed a decrease in the artifact area from DWI to ADC images (p ≤ 0.037).ConclusionBreast clip-marker MRI artifact appearances depend on clip type, field strength, and sequence and may reach a significant size, potentially obscuring smaller lesions and hindering accurate assessment of breast tumors.Relevance statementConsiderable variations in artifact size and characteristics across different breast clips, MRI sequences, and field strengths exist. Awareness of these artifacts and their characteristics is essential to ensure accurate interpretation of scans and appropriate treatment planning.Key PointsAwareness of breast clip artifacts is essential for accurate interpretation of MRI.The appearance of artifacts depends on breast clip type, field strength, and sequence.Clip-related artifacts might hinder the visibility of small lesions.Graphical

Papillary Lesions of the Breast: Addition of DWI and TIRM Sequences to Routine Breast MRI Could Help in Differentiation Benign from Malignant.

We aimed to investigate the magnetic resonance imaging (MRI) features of benign, atypical, or malignant papillary breast lesions and to assess the additional value of diffusion-weighted imaging (DWI) and turbo inversion recovery magnitude (TIRM) sequences to routine breast MRI. Differentiation between benign and malignant papillary breast lesions is essential for patient management. However, morphologic features and enhancement patterns of malignant papillary lesions may overlap with those of benign papilloma. Seventy-two papillary breast lesions (50 benign, 22 atypical or malignant) were included in the current study, retrospectively. We divided the patients into two groups: benign papillary breast lesions and atypical or malignant papillary breast lesions. Morphologic, dynamic, turbo inversion recovery magnitude (TIRM) values and diffusion features of the papillary lesions were compared between two groups. Benign papillary lesions were smaller in size (p=0.006 and p=0.005, for radiologists 1 and 2 respectively), closer to the areola (p=0.045 and 0.049 for radiologist 1 and 2 respectively), and had higher ADC values (p=0.001 for two radiologists) than the atypical or malignant group. ROC curves showed diagnostic accuracy for ADC (AUC=0.770 and 0.762, p = 0.0001 for two radiologists), and showed a cut-off value of ≤ 957 x 10-6 mm2/s (radiologist 1) and ≤ 910 x 10-6 mm2/s (radiologist 2). MRI is a useful method for differentiation between benign and malignant papillary breast lesions. Centrally located, lesser in size, and higher ADC values should be considered benign, whereas peripherally located, larger in size, and lower ADC values should be considered malignant.

Non-Invasive Assessment of Hypoxia and Neovascularization with MRI for Identification of Aggressive Breast Cancer.

The aim of this study was to investigate the potential of magnetic resonance imaging (MRI) for a non-invasive synergistic assessment of tumor microenvironment (TME) hypoxia and induced neovascularization for the identification of aggressive breast cancer. Fifty-three female patients with breast cancer underwent multiparametric breast MRI including quantitative blood-oxygen-level-dependent (qBOLD) imaging for hypoxia and vascular architecture mapping for neovascularization. Quantitative MRI biomarker maps of oxygen extraction fraction (OEF), metabolic rate of oxygen (MRO2), mitochondrial oxygen tension (mitoPO2), microvessel radius (VSI), microvessel density (MVD), and microvessel type indicator (MTI) were calculated. Histopathology was the standard of reference. Histopathological markers (vascular endothelial growth factor receptor 1 (FLT1), podoplanin, hypoxia-inducible factor 1-alpha (HIF-1alpha), carbonic anhydrase 9 (CA IX), vascular endothelial growth factor C (VEGF-C)) were used to confirm imaging biomarker findings. Univariate and multivariate regression analyses were performed to differentiate less aggressive luminal from aggressive non-luminal (HER2-positive, triple negative) malignancies and assess the interplay between hypoxia and neoangiogenesis markers. Aggressive non-luminal cancers (n = 40) presented with significantly higher MRO2 (i.e., oxygen consumption), lower mitoPO2 values (i.e., hypoxia), lower MTI, and higher MVD than less aggressive cancers (n = 13). Data suggest that a model derived from OEF, mitoPO2, and MVD can predict tumor proliferation rate. This novel MRI approach, which can be easily implemented in routine breast MRI exams, aids in the non-invasive identification of aggressive breast cancer.

Value of Apparent Diffusion Coefficient Values in Differentiating Malignant and Benign Breast Lesions.

Magnetic resonance imaging (MRI) has become a diagnostic and problem solving method for the breast examinations in addition to conventional breast examination methods. Diffusion-weighted imaging (DWI) adds valuable information to conventional MRI. Our aim was to show the impact of apparent diffusion coefficient (ADC) values acquired with DWI to differentiate benign and malignant breast lesions. Diagnostic accuracy study. Forty-six women with 58 breast masses (35 malignant, 23 benign) were examined on a 1.5 T clinical MRI scanner. The morphologic characteristics of the lesions on conventional MRI sequences and contrast uptake pattern were assessed. ADC values of both lesions and normal breast parenchyma were measured. The ADC values obtained were statistically compared with the histopathologic results using Paired Samples t-Test. Multiple lesions were detected in 12 (26%) of the patients, while only one lesion was detected in 34 (74%). Overall, 35 lesions out of 58 were histopathologically proven to be malignant. In the dynamic contrast-enhanced series, 5 of the malignant lesions were type 1, while 8 benign lesions revealed either type 2 or 3 time signal intensity curves (85% sensitivity, 56% spesifity). Mean ADC values were significantly different in malignant vs. benign lesions. (1.04±0.29×10(-3) cm(2)/sec vs. 1.61±0.50×10(-3) cm(2)/sec for the malignant and benign lesions, respectively, p=0.03). A cut-off value of 1.30×10(-3) mm(2)/sec for ADC detected with receiver operating characteristic analysis yielded 89.1% sensitivity and 100% specificity for the differentiation between benign and malignant lesions. ADC values improve the diagnostic accuracy of solid breast lesions when evaluated with the conventional MRI sequences. Therefore, DWI should be incorporated to routine breast MRI protocol.

Quantitative 3D breast magnetic resonance imaging fibroglandular tissue analysis and correlation with qualitative assessments: a feasibility study.

The amount of fibroglandular tissue (FGT) has been linked to breast cancer risk based on mammographic density studies. Currently, the qualitative assessment of FGT on mammogram (MG) and magnetic resonance imaging (MRI) is prone to intra and inter-observer variability. The purpose of this study is to develop an objective quantitative FGT measurement tool for breast MRI that could provide significant clinical value. An IRB approved study was performed. Sixty breast MRI cases with qualitative assessment of mammographic breast density and MRI FGT were randomly selected for quantitative analysis from routine breast MRIs performed at our institution from 1/2013 to 12/2014. Blinded to the qualitative data, whole breast and FGT contours were delineated on T1-weighted pre contrast sagittal images using an in-house, proprietary segmentation algorithm which combines the region-based active contours and a level set approach. FGT (%) was calculated by: [segmented volume of FGT (mm(3))/(segmented volume of whole breast (mm(3))] ×100. Statistical correlation analysis was performed between quantified FGT (%) on MRI and qualitative assessments of mammographic breast density and MRI FGT. There was a significant positive correlation between quantitative MRI FGT assessment and qualitative MRI FGT (r=0.809, n=60, P<0.001) and mammographic density assessment (r=0.805, n=60, P<0.001). There was a significant correlation between qualitative MRI FGT assessment and mammographic density assessment (r=0.725, n=60, P<0.001). The four qualitative assessment categories of FGT correlated with the calculated mean quantitative FGT (%) of 4.61% (95% CI, 0-12.3%), 8.74% (7.3-10.2%), 18.1% (15.1-21.1%), 37.4% (29.5-45.3%). Quantitative measures of FGT (%) were computed with data derived from breast MRI and correlated significantly with conventional qualitative assessments. This quantitative technique may prove to be a valuable tool in clinical use by providing computer generated standardized measurements with limited intra or inter-observer variability.

Automatic Classification of Breast Tumors Using Features Extracted from Magnetic Resonance Images

Breast cancer is considered as the second leading cause of cancer deaths among women in the United States. Early detection of cancer is crucial in order to reduce its negative effects. Recently, magnetic resonance imaging (MRI) has become an important modality in the detection of breast cancer in daily practice. However, routine breast MRI has a moderate specificity that may increase its false positive rates. Therefore, automated detection techniques of malignancy can provide an important tool for clinicians. In this study, different data classification methods were examined to classify breast tumors screened using contrast enhanced MRI. The used data set included 20 subjects categorized clinically into two groups; benign and malignant tumors. MRI scans were first preprocessed to extract imaging features. Then two classification methods were exploited to differentiate between the two tumor's categories using the extracted features. The used classification methods were K-Nearest Neighbor (KNN), and Linear Discriminant Analysis (LDA). The results show a relatively significant classification accuracy compared with pathological analysis, and also the calculated resubstitution error. In summary, the proposed automatic classification techniques can be used as noninvasive diagnostic tools for breast cancer, with the capability of decreasing false positive errors associated with regular MRI diagnosis.

Abstract P5-01-09: Improving specificity and refining diagnostic accuracy of MRI in breast cancer with dedicated breast PET (dbPET)

Abstract BACKGROUND. Continued progress in the control of breast cancer will require sustained efforts to provide high-quality screening, diagnosis, and treatment to all segments of the population. MRI has the advantages of providing a 3D view of the breast with high sensitivity, using non-ionizing radiation. However, MRI has significant limitations including its moderate specificity that, in combination with high sensitivity, often leads to unnecessary biopsies. Recently, the MAMmography with Molecular Imaging (MAMMI) dedicated breast PET (dbPET) has emerged as an additional imaging tool for breast cancer diagnosis, clarification of complex lesions and therapy follow-up. It is well known that 18F-FDG-PET has high specificity by assessing metabolic activity, potentially reducing the number of false positive findings. To compare FDG-dbPET with the conventional magnetic resonance imaging (MRI) on breast lesion characterization, we analyzed sensitivity, specificity, Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of 37 cases of patients with BC using both dbPET and MRI. METHODS. Thirty-seven women with known or suspected breast carcinoma (41 lesions: 36 invasive carcinomas, 2 noninvasive carcinomas, 1 case of ductal hyperplasia, and 2 benign lesions) were enrolled in this study. Both a prone dbPET Mammi scan, and routine breast MRI scans were performed. A joint reading of MRI and PET scans side-by-side by a nuclear medicine physician and a radiologist was performed. Sensitivity and specificity of MRI and dbPET scans were calculated on the basis of post-surgical pathology reports. Breast MRI examinations were performed in a 1.5-T or 3-T commercial imager (Siemens Medical Solutions) with the use of a dedicated breast coil. The imaging sequence included a sagittal T1-weighted localizing sequence followed by a sagittal T2- weighted sequence. A T1-weighted 3D, fat-suppressed fast spoiled-gradient-echo sequence was then performed with an injection of 0.1 mmol per kilogram body weight of gadolinium dimeglumine (Magnevist; Schering). A prone position high-resolution dedicated breast PET was performed 60 min after administration of 90-120 MBq of 18F-FDG. RESULTS. A total of 41 lesions were assessed. Lesion size range was 0.2 to 7.6 cm. In lesion-by-lesion analysis, sensitivity and specificity of MRI alone were 91% and 54%, respectively; while lesion-based sensitivity of dbPET was 93% and breast-based specificity was 100%. The positive predictive value and the negative predictive value for MRI alone were 69% and 85%, respectively; and for dbPET were 100% and 89%, respectively. In a significant number of cases, dbPET helped to clarify or disprove positive findings by MRI, and in four cases helped to define new positives that had gone unnoticed at MRI, CONCLUSION: Dedicated breast PET scans increase the specificity of MRI. False positives, one of the most challenging aspects of MRI in breast lesions, are reduced. The results of the current study show that FDG-dbPET is more effective than MRI in detecting true breast cancer positives. Its functional information may improve the likelihood of a successful excision, reduce costs from additional procedures, and minimize discomfort and anxiety for the patient. Citation Format: Ines Dominguez, Michel Herranz, Sze Yiun Teo, Elena Brozos, Carmela Rodriguez, Jasper Chaal, Juan Cueva, Jose Ramon Antúnez, Gabriel Gonzalez Pavón, Marielle Fortier, Rafael López, Alvaro Ruibal. Improving specificity and refining diagnostic accuracy of MRI in breast cancer with dedicated breast PET (dbPET) [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P5-01-09.

Diffusionsgewichtete Brustbildgebung

Diffusion-weighted imaging (DWI) of the breast provides additional contrast information in breast magnetic resonance imaging (MRI). The DWI procedure can easily be implemented in the routine breast MRI protocol with little time expenditure regarding image acquisition and evaluation. Evaluation of the DW images can be performed with or without the routine breast MRI sequences (T2w and T1w with contrast material) but evaluation in combination with the routine program is highly recommended. Objective analysis of the tissue diffusion can be achieved by calculating the apparent diffusion coefficient (ADC) value with the scanner software. The choice of the DW sequence, evaluation and determination of the ADC threshold to differentiate between benign and malignant lesions should be scanner adapted. The use of DW imaging qualifies for routine use regarding the differentiation between malignant and benign breast lesions. Non-mass-like lesions and monitoring neoadjuvant chemotherapy can also be evaluated with DW sequences. The benefit of the additional information from DW-MR mammography to characterize non-mass-like lesions and in the course of neoadjuvant chemotherapy remains unclear to date.

Patterns of Breast Magnetic Resonance Imaging Use

Both theAmericanCancerSociety1and theNationalComprehensiveCancerNetwork2havepublishedguidelinesonthe recommended use of breast magnetic resonance imaging (MRI). In both sets of guidelines, lifetime breast cancer risk greater than 20%has been established as an acceptable threshold for annualMRI screeningwhenused togetherwith annualmammography screening. Routine breast MRI screening is not recommended for a new cancer diagnosis or for cancer surveillance. Nevertheless,MRI remains frequentlyused for theseother indications. A systematic review of the accuracy of MRI and its impact on surgical treatment of breast cancer showed that the use of MRI for treatment planning is widespread, although its benefit remains difficult todemonstrate.3 For evaluation of the contralateral breast in patients with a new diagnosis of breast cancer, the American College of Radiology Imaging Network (ACRIN) 6667 trial found that the contralateral breast cancer detection rate with breast MRI was 3.1%, indicating possible utility in this setting.4Recent studieshavealso indicatedvalue forbreastMRI inneoadjuvant treatmentwherebreastMRImay have clinical utility both in treatment planning and as a prognosticmarker.5 As yet, however, the impact ofMRI on clinical management has not been linked to improvements in breast cancer outcomes.

Arterial spin labelling perfusion MRI of breast cancer using FAIR TrueFISP: Initial results

To assess the feasibility of an unenhanced, flow-sensitive, alternating inversion recovery-balanced steady-state free precession (FAIR TrueFISP) arterial spin labelling (ASL) magnetic resonance imaging (MRI) technique for quantification of breast cancer perfusion. Eighteen untreated breast tumour patients (mean age 53 ± 17 years, range 30-68 years) and four healthy controls (mean age 51 ± 14 years, range 33-68 years) were enrolled in this study and were imaged using a clinical 1.5 T MRI machine. Perfusion measurements were performed using a coronal single-section ASL FAIR TrueFISP technique in addition to a routine breast MRI examination. T1 relaxation time of normal breast parenchyma was determined in four healthy volunteers using the variable flip angle approach. The definitive diagnosis was obtained at histology after biopsy or surgery and was available for all patients. ASL perfusion was successfully acquired in 13 of 18 tumour patients and in all healthy controls. The mean ASL perfusion of invasive ductal carcinoma tissue was significantly higher (88.2 ± 39.5 ml/100 g/min) compared to ASL perfusion of normal breast parenchyma (24.9 ± 12.7 ml/100 g/min; p < 0.05) and invasive lobular carcinoma (30.5 ± 4.3 ml/100 g/min; p < 0.05). No significant difference was found between the mean ASL perfusion of normal breast parenchyma and invasive lobular carcinoma tissue (p = 0.97). ASL MRI enables quantification of breast cancer perfusion without the use of contrast material. However, its impact on diagnosis and therapy management of breast tumours has to be evaluated in larger patient studies.

Preoperative breast MRI in early-stage breast cancer

Rapid uptake of new imaging technology is a major contributor to rising healthcare costs. Preoperative breast magnetic resonance imaging (MRI) for patients with early-stage breast cancer has dramatically increased in use without the evidence of improved outcomes compared to standard assessment and is associated with higher rates of mastectomy. A decision analytic model was developed to evaluate the impact of adding breast MRI to the preoperative evaluation of women with early-stage breast cancer who were candidates for breast-conserving therapy on patient outcomes measured in quality-adjusted life years (QALYs). Model inputs, including survival, recurrence rates, and health utilities, were obtained from a comprehensive literature review. One-way sensitivity analyses were performed to estimate threshold values for key parameters at which adding MRI would become the optimal imaging strategy over standard assessment. Preoperative MRI resulted in 17.77 QALYs compared to 17.86 QALYs with standard assessment, a decrease of 0.09 QALYs or 34 days. In sensitivity analyses, standard assessment was associated with better patient outcomes than preoperative breast MRI across all plausible probabilities for mastectomy, local recurrence, and health utilities. For routine preoperative breast MRI to become the optimal strategy, the conversion rate to mastectomy after preoperative MRI would need to be <1 % (versus the range of 3.6-33 % reported in the literature). Routine preoperative breast MRI appears to confer no advantage over the standard diagnostic evaluations for early-stage breast cancer and may lead to worse patient outcomes.

P2-08-13: Does Routine Use of Preoperative Magnetic Resonance Imaging (MRI) in Breast Cancer Influence the Outcome?

Abstract Introduction: The role of routine preoperative breast MRI in patients diagnosed with breast cancer is still under discussion. In a milestone review, Houssami et al. (CA Cancer J Clin 2009;59;290) did not demonstrate an advantage with regard to DFS or OS. We reviewed our case series (n=793) in order to add evidence to the current discussion of whether or not preoperative MRI would influence the outcome. Material and Methods: In our database we identified four years of diagnosis (2004-07) in which a high percentage (72%) of patients (349 of 483) with histologically confirmed invasive breast cancer received preoperative MRI. In the following years (2008/09), MRI was still done in 31% of the cases (97 of 309). All pts were treated according to national guidelines; however, patients with additional lesions in MRI were subjected to an additional MRI-guided needle biopsy or additional wire-guided excision. The median follow-up time was 31.5 months (0-81). The patients were followed clinically. In most cases local surveillance was done by mammography. Results: In the total cohort, 20% of the patients had additional needle biopsies and/or wire-localisation due to MRI-findings. By MRI, lesions that subsequently led to an additional preoperative needle biopsy were found in 82 pts. Interestingly, only ten contralateral second cancers were found. In 357 pts, MRI was used as guidance during the operation with (n=118) or without MRI-supported wire localization (n=238). The percentage of additional MRI-needle biopsy or MRI-supported localisation did not differ between invasive ductal (n=655) and lobular cancer (n=91): 10% versus 13% needle biopsies and 15% versus 20% wire localisations. The number of surgical procedures to achieve tumor-free margins did not differ between patients with or without preoperative MRI. In this series, 69 of 100 patients who received neoadjuvant chemotherapy, also had MRI-imaging. Considering the patient cohort with follow-up available (n=737), no significant difference of DFS probability was observed between pts with and without preoperative MRI. Discussion: This retrospective analysis did not demonstrate any advantage for routine preoperative MRI with regard to local treatment and DFS probability. The observed rate of 20% additional operative procedures corresponds to similar published data (16% additional multicentric or multifocal lesions found by MRI, Solin, Breast. 2010;19:7). Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-08-13.

Preoperative breast MRI in early-stage breast cancer: A decision analysis.

6035 Background: Rapid uptake of new imaging technology is a major contributor to rising health care costs. Preoperative breast magnetic resonance imaging (MRI) for patients with early-stage breast cancer has dramatically increased in use without evidence of improved outcomes compared to standard triple assessment (clinical examination, imaging with mammography and/or ultrasonography, and needle biopsy) and is associated with higher rates of mastectomy. Methods: A decision analytic model was developed to evaluate the impact of adding breast MRI to the preoperative evaluation of women with early-stage breast cancer who were candidates for breast-conserving therapy (BCT) on patient outcome measures in quality-adjusted-life-years (QALYs). Model inputs including survival, recurrence rates, and health utilities were obtained from a comprehensive literature review. One-way sensitivity analyses were performed to estimate threshold values for key parameters at which adding MRI would become the optimal imaging strategy over standard triple assessment. Results: Preoperative breast MRI was associated with a decrease of 0.094 QALYs compared with no MRI, based on a 20-year life expectancy after diagnosis of early-stage breast cancer. In order for routine preoperative breast MRI to become the optimal strategy, the conversion rate to mastectomy after preoperative MRI would need to be <1% (vs. range of 3.6-54% reported in the literature) Across a wide range of local recurrence rates following BCT, MRI remained inferior to no MRI. Conclusions: Routine preoperative breast MRI appears to confer no advantage over standard diagnostic evaluations for early-stage breast cancer and may lead to worse outcomes.

Is there a role for BLADE acquisition in T2-weighted breast MRI?

standard T2-weighted (T2W) magnetic resonance imaging (MRI) is a necessary component of routine breast MRI. However, breast MRI suffers from minor subject movements, which degrade the image quality. BLADE acquisition MRI is a promising motion degradation method currently used in brain imaging. to compare T2W BLADE acquisition breast MR images with routine T2W images in the evaluation of motion artifacts and overall image quality. MRI was performed with a 1.5 T system on 25 volunteers and 25 consecutive patients with identical imaging parameters for both MRI sequences (TR 5240 ms, TE 112-108 ms, acquisition 1, spatial resolution 0.9×0.9× 4 mm). Motion and flow artifacts and pectoral muscle and lesion contour delineations were assessed. Signal to noise ratios (SNRs) of images and contrast to noise ratios (CNRs) of the incidental lesions were calculated. The results were evaluated with the Wilcoxon signed-ranks test. of the 50 patients, 44 were included in the analysis (mean age 42.1 years). Motion artifacts were prominent in 48% cases on routine T2W and in only 2% of BLADE cases. The SNR values of BLADE images were significantly higher than routine T2W (P<0.05). Pectoral muscle contours were better assessed on BLADE in all cases. Sequence performances were similar in flow artifacts, CNR values, and contour delineation of incidental lesions. The readers chose BLADE sequence MRI in 25 cases and found the overall performance of sequences equal in 19 cases. None of the readers preferred routine T2W to BLADE. the performance of BLADE is superior to routine T2W images in eliminating motion artifacts, provides better SNRs, shows detailed pectoral muscle contours, and may be the sequence of choice.