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Purpose To develop a bilateral coil and fat suppressed T1-weighted sequence for 7 Tesla (T) breast MRI. Materials and Methods A dual-solenoid coil and three-dimensional (3D) T1w gradient echo sequence with B1+ insensitive fat suppression (FS) were developed. T1w FS image quality was characterized through image uniformity and fat–water contrast measurements in 11 subjects. Signal-to-noise ratio (SNR) and flip angle maps were acquired to assess the coil performance. Bilateral contrast-enhanced and unilateral high resolution (0.6 mm isotropic, 6.5 min acquisition time) imaging highlighted the 7T SNR advantage. Results Reliable and effective FS and high image quality was observed in all subjects at 7T, indicating that the custom coil and pulse sequence were insensitive to high-field obstacles such as variable tissue loading. 7T and 3T image uniformity was similar (P = 0.24), indicating adequate 7T B1+ uniformity. High 7T SNR and fat–water contrast enabled 0.6 mm isotropic imaging and visualization of a high level of fibroglandular tissue detail. Conclusion 7T T1w FS bilateral breast imaging is feasible with a custom radiofrequency (RF) coil and pulse sequence. Similar image uniformity was achieved at 7T and 3T, despite different RF field behavior and variable coil–tissue interaction due to anatomic differences that might be expected to alter magnetic field patterns. J. Magn. Reson. Imaging 2014;39:540–549. © 2013 Wiley Periodicals, Inc.

The incidence of ductal carcinoma in situ (DCIS) has increased over the past few decades and now accounts for over 20% of newly diagnosed cases of breast cancer. Although the detection of DCIS has increased with the advent of widespread mammography screening, it is essential to have a more accurate assessment of the extent of DCIS for successful breast conservation therapy. Recent studies evaluating the detection of DCIS with magnetic resonance (MR) imaging have used high spatial resolution techniques and have increasingly been performed to screen a high-risk population as well as to evaluate the extent of disease. This work has shown that MR imaging is the most sensitive modality currently available for identifying DCIS and is more accurate than mammography in evaluating the extent of DCIS. MR imaging is particularly sensitive for identifying high-grade and intermediate-grade DCIS. DCIS may have variable morphologic features on MR images, with non-mass enhancement morphology being the most common manifestation. Less commonly, DCIS may also manifest as a mass on MR images, in which case it is most likely to be irregular. The kinetics of DCIS are also variable, with fast uptake and a plateau curve reported as the most common kinetic pattern. Additional MR imaging tools such as diffusion-weighted imaging and quantitative kinetic analysis combined with the benefit of high field strength, such as 3 T, may increase the sensitivity and specificity of breast MR imaging in the detection of DCIS.

Breast magnetic resonance (MR) imaging is increasingly performed for a variety of indications, most commonly with the goal of detecting breast cancer. Percutaneous biopsy (usually under MR guidance or ultrasound if there is a correlating finding) is commonly used to evaluate suspicious imaging findings detected on MR imaging with the goal of identifying malignancy. It is important to be familiar with the characteristics and management of high-risk lesions detected or biopsied under MR guidance. This review focuses on the appearance of a variety of breast lesions detected on MR imaging that require excision with focus on pathologic correlation.

To evaluate the image quality of T1-weighted fat-suppressed breast MRI at 7 T and to compare 7-T and 3-T images.Seventeen subjects were imaged using a 7-T bilateral transmit-receive coil and 3D gradient echo sequence with adiabatic inversion-based fat suppression (FS). Images were graded on a five-point scale and quantitatively assessed through signal-to-noise ratio (SNR), fibroglandular/fat contrast and signal uniformity measurements.Image scores at 7 and 3 T were similar on standard-resolution images (1.1 × 1.1 × 1.1-1.6 mm(3)), indicating that high-quality breast imaging with clinical parameters can be performed at 7 T. The 7-T SNR advantage was underscored on 0.6-mm isotropic images, where image quality was significantly greater than at 3 T (4.2 versus 3.1, P ≤ 0.0001). Fibroglandular/fat contrast was more than two times higher at 7 T than at 3 T, owing to effective adiabatic inversion-based FS and the inherent 7-T signal advantage. Signal uniformity was comparable at 7 and 3 T (P 0.05). Similar 7-T image quality was observed in all subjects, indicating robustness against anatomical variation.The 7-T bilateral transmit-receive coil and adiabatic inversion-based FS technique produce image quality that is as good as or better than at 3 T.• High image quality bilateral breast MRI is achievable with clinical parameters at 7 T. • 7-T high-resolution imaging improves delineation of subtle soft tissue structures. • Adiabatic-based fat suppression provides excellent fibroglandular/fat contrast at 7 T. • 7- and 3-T 3D T1-weighted gradient-echo images have similar signal uniformity. • The 7-T dual solenoid coil enables bilateral imaging without compromising uniformity.

Purpose To assess two methods of fat and fibroglandular tissue (FGT) segmentation for measuring breast MRI FGT volume and FGT%, the volume percentage of FGT in the breast, in longitudinal studies. Materials and Methods Nine premenopausal women provided one MRI per week for 4 weeks during a natural menstrual cycle for a total of 36 datasets. We compared a fuzzy c-means (FC) and a 3-point Dixon segmentation method for estimation of changes in FGT volume and FGT% across the menstrual cycle. We also assessed whether differences due to changes in positioning each week could be minimized by coregistration, i.e., the application of the breast boundary selected at one visit to images obtained at other visits. Results FC and Dixon FGT volume were highly correlated (r = 0.93, P < 0.001), as was FC and Dixon FGT% (r = 0.86, P = 0.01), although Dixon measurements were on average 10–20% higher. Although FGT measured by both methods showed the expected pattern of increase during the menstrual cycle, the magnitude, and for one woman the direction, of change varied according to the method used. Measurements of FGT for coregistered images were in close agreement with those for which the boundaries were determined independently. Conclusion The method of segmentation of fat and FGT tissue may have an impact on the results of longitudinal studies of changes in breast MRI FGT. J. Magn. Reson. Imaging 2013;38:474–481. © 2012 Wiley Periodicals, Inc.

To evaluate uptake, patterns of use, and perception of digital breast tomosynthesis (DBT) among practicing breast radiologists.Institutional Review Board exemption was obtained for this Health Insurance Portability and Accountability Act-compliant electronic survey, sent to 7023 breast radiologists identified via the Radiological Society of North America database. Respondents were asked of their geographic location and practice type. DBT users reported length of use, selection criteria, interpretive sequences, recall rate, and reading time. Radiologist satisfaction with DBT as a diagnostic tool was assessed (1-5 scale).There were 1156 (16.5%) responders, 65.8% from the United States and 34.2% from abroad. Of these, 749 (68.6%) use DBT; 22.6% in academia, 56.5% private, and 21% other. Participants are equally likely to report use of DBT if they worked in academics versus in private practice (78.2% [169 of 216] vs 71% [423 of 596]) (odds ratio, 1.10; 95% confidence interval: 0.87-1.40; P = 1.000). Of nonusers, 43% (147 of 343) plan to adopt DBT. No US regional differences in uptake were observed (P = 1.000). Although 59.3% (416 of 702) of DBT users include synthetic 2D (s2D) for interpretation, only 24.2% (170 of 702) use s2D alone. Majority (66%; 441 of 672) do not perform DBT-guided procedures. Radiologist (76.6%) (544 of 710) satisfaction with DBT as a diagnostic tool is high (score ≥ 4/5).DBT is being adopted worldwide across all practice types, yet variations in examination indication, patient selection, utilization of s2D images, and access to DBT-guided procedures persist, highlighting the need for consensus and standardization.

MRI-guided needle localization allows access to MRI-detected mammographically occult breast lesions that are not amenable to MRI-guided biopsy. The purpose of this study was to examine the safety and outcomes of MRI-guided needle localization.Ninety-nine consecutive breast lesions that underwent preoperative MRI-guided needle localization were identified. Clinical indications for breast MRI, reasons for performing MRI-guided needle localization, and surgical pathology results were recorded. Lesion characteristics, procedure time, and complications were assessed.Of 99 lesions, 60 (60.6%) were in a location inaccessible for MRI biopsy, necessitating MRI-guided needle localization. Histologic evaluation revealed 38 (38.4%) carcinomas, 31 (31.3%) high-risk lesions, and 30 (30.3%) benign lesions. Carcinoma was more likely to be found in women with known cancer (31/61 [50.8%]; p = 0.003) than in women undergoing imaging for high-risk screening (2/18 [11.1%]) or problem solving (6/20 [30%]). Masses (p = 0.013) and foci (p0.001) were more likely to be malignant than were lesions with nonmass enhancement. Foci were significantly more often malignant compared with all other lesion types (9/10 [90%]; p0.001). The mean (± SD) procedure time was 32.9 ± 9.39 minutes. All lesions were occult on specimen radiographs. There were no procedure-related complications.The positive predictive value of MRI-guided needle localization (38.4%) is comparable to that of mammography- and tomosynthesis-guided localizations and is highest in women with a known diagnosis of cancer. It is highly accurate in targeting small enhancing lesions, thereby improving surgical management. MRI-guided needle localization is a safe, accurate, and time-efficient procedure.

Diffusion-weighted imaging (DWI) andIn this Health Insurance Portability and Accountability Act-compliant prospective study, with written informed consent and approval of the institutional review board and using simultaneously acquired FDG-PET and DWI, tissue diffusion (DSUV||DSimultaneously acquired and registered FDG-PET/DWI allowed quantifiable descriptions of breast cancer microenvironments that may provide a framework for monitoring and predicting response to treatment. Magn Reson Med 78:1147-1156, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

To compare background parenchymal enhancement (BPE) over time in patients with and without breast cancer.This retrospective Institutional Review Board (IRB)-approved, Health Insurance Portability and Accountability Act (HIPAA)-compliant study included 116 women (25-84 years, mean 54 years) with breast cancer who underwent breast magnetic resonance imaging at 3T between 1/2/2009 and 12/29/2009 and 116 age and date-of-exam-matched women without breast cancer (23-84 years, mean 51 years). Two independent, blinded readers (R1, R2) recorded BPE (minimal, mild, moderate, marked) at three times (100, 210, and 320 seconds postcontrast). Subsequent cancers were diagnosed in 9/96 control patients with follow up (12.6-93.0 months, mean 63.6 months). Exact Mann-Whitney, Fisher's exact, and McNemar tests were performed.Mean BPE was not found to be different between patients with and without breast cancer at any time (P = 0.36-0.64). At time 2 as compared with time 1, there were significantly more patients, both with and without breast cancer, with BPEminimal (R1: 90 vs. 41 [P0.001] and 81 vs. 36 [P0.001]; R2: 84 vs. 52 [P0.001] and 79 vs. 43 [P0.001]) and BPEmild (R1: 59 vs. 10 [P0.001] and 47 vs. 13 [P0.001]; R2: 49 vs. 12 [P0.001] and 41 vs. 18 [P0.001]). BPE changes between times 2 and 3 were not significant (P = 0.083-1.0). Odds ratios for control patients developing breast cancer were significant only for R2 and ranged up to 7.67 (1.49, 39.5; P0.01) for BPEmild at time 2.BPE changes between the first and second postcontrast scans and stabilizes thereafter in most patients. Further investigation into the most clinically relevant timepoint for BPE assessment is warranted.3 J. Magn. Reson. Imaging 2017;45:74-83.

To explore the application of diffusion tensor imaging (DTI) for breast tissue and breast pathologies using a stimulated-echo acquisition mode (STEAM) with variable diffusion times.In this Health Insurance Portability and Accountability Act-compliant study, approved by the local institutional review board, eight patients and six healthy volunteers underwent an MRI examination at 3 Tesla including STEAM-DTI with several diffusion times ranging from 68.5 to 902.5 ms. A DTI model was fitted to the data for each diffusion time, and parametric maps of mean diffusivity, fractional anisotropy, axial diffusivity, and radial diffusivity were computed for healthy fibroglandular tissue (FGT) and lesions. The median value of radial diffusivity for FGT was fitted to a linear decay to obtain an estimation of the surface-to-volume ratio, from which the radial diameter was calculated.For healthy FGT, radial diffusivity presented a linear decay with the square root of the diffusion time resulting in a range of estimated radial diameters from 202 to 496 µm, while axial diffusivity presented a nearly time-independent diffusion. Residual fat signal was reduced at longer diffusion times due to the shorter T1 of fat. Residual fat signal to the overall signal in the healthy volunteers' FGT was found to range from 2.39% to 2.55% (shortest mixing time), and from 0.40% to 0.51% (longest mixing time) for the b500 images.The use of variable diffusion times may provide an in vivo noninvasive tool to probe diffusion lengths in breast tissue and breast pathology, and might aid by improving fat suppression at longer diffusion times.2 J. Magn. Reson. Imaging 2017;45:84-93.

This study was performed to determine the frequency, predictors, and outcomes of ultrasound (US) correlates for non-mass enhancement.From January 2005 to December 2011, a retrospective review of 5837 consecutive breast magnetic resonance imaging examinations at our institution identified 918 non-mass enhancing lesions for which follow-up or biopsy was recommended. Retrospective review of the images identified 879 of 918 lesions (96%) meeting criteria for non-mass enhancement. Patient demographics, pathologic results, and the presence of an adjacent landmark were recorded. Targeted US examinations were recommended for 331 of 879 cases (38%), and 284 of 331 women (86%) underwent US evaluations.The US correlate rate for non-mass enhancement was 23% (64 of 284). An adjacent landmark was significantly associated with a US correlate (P .001). Biopsy was recommended for 43 of 64 correlates (67%). Ultrasound-guided biopsy was performed on 39 of 43 (91%); 7 of 39 (18%) were malignant. No correlate was seen for 220 of 284 lesions (77%). At magnetic resonance imaging-guided biopsy, 14 of 117 (12%) were malignancies. For all biopsied non-mass enhancements, the malignancy rate was 18% (55 of 308) and was significantly more prevalent in the setting of a known index cancer (P .001), older age (P .001), the presence of a landmark (P = .002), and larger lesion size (P = .019).Non-mass enhancement with an adjacent landmark is more likely to have a US correlate compared to non-mass enhancement without an adjacent landmark. Non-mass enhancement in the setting of a known index cancer, older age, a landmark, and larger lesion size is more likely to be malignant. However, no statistical difference was detected in the rate of malignancy between non-mass enhancement with (18%) or without (12%) a correlate. Absence of a correlate does not obviate the need to biopsy suspicious non-mass enhancement.

Rationale and Objectives To investigate whether quantitative kinetic analysis of lesions and background parenchyma in breast magnetic resonance imaging can elucidate differences between BRCA carriers and sporadic controls with high risk for breast cancer. Materials and Methods Fifty-nine BRCA and 59 control cases (49 benign, 10 malignant) were examined in this study. Principal component analysis was applied for quantitative analysis of dynamic signal in background parenchyma (B) and lesion (L) in terms of initial enhancement ratio (IER) and delayed enhancement ratio (DER). Results Control B-IER, B-DER, L-IER, and L-DER were higher than BRCA cases in all women and in women with benign lesions; statistically significant differences in B-IER and B-DER (all women: P = 0.02 and P = 0.02, respectively; benign only: P = 0.005 and P = 0.005, respectively). In the control cohort, B-IER and B-DER were higher in the premenopausal women than in the postmenopausal women ( P = 0.013 and 0.003, respectively), but not in the BRCA cohort; this led to significant differences in B-IER and B-DER between the control and the BRCA groups in the premenopausal women ( P = 0.01 and 0.01, respectively) but not in the postmenopausal women. Conclusion Results suggest possible differences in the vascular properties of background parenchyma between BRCA carriers and noncarriers and its association with menopausal status.

Women at high risk for breast cancer and women with newly diagnosed breast cancer often undergo breast MRI. With the increasing availability of MRI-guided biopsy, high-risk lesions are not infrequently encountered. These high-risk lesions include atypical ductal hyperplasia, lobular carcinoma in situ, atypical lobular hyperplasia, papilloma, radial scar, and flat epithelial cell atypia. The management of these lesions is controversial and is often extended to high-risk lesions detected on mammography and ultrasound, with surgical excision usually recommended. The increasing use of MRI for suspicious lesions necessitates review of the imaging characteristics, frequency, and surgical outcome of high-risk lesions identified at MRI. This article addresses the frequency of high-risk lesions detected on breast MRI according to the current literature and discusses MRI features of high-risk lesions, including morphologic and enhancement kinetic characteristics. The surgical outcome for high-risk lesions identified at MRI-guided biopsy will be discussed. Finally, appropriate management guidelines for high-risk lesions identified on MRI-guided biopsy will be determined.To our knowledge, no studies to date show definitive and specific characteristics for high-risk lesions. Underestimation of malignancy on MRI-guided biopsy currently warrants surgical management for all high-risk lesions. There is a need for prospective larger power studies.

The effective delivery of a therapeutic drug to the core of a tumor is often impeded by physiological barriers, such as the interstitial fluid pressure (IFP). There are a number of therapies that can decrease IFP and induce tumor vascular normalization. However, a lack of a noninvasive means to measure IFP hinders the utilization of such a window of opportunity for the maximization of the treatment response. Thus, the purpose of this study was to investigate the feasibility of using intravoxel incoherent motion (IVIM) diffusion parameters as noninvasive imaging biomarkers for IFP. Mice bearing the 4T1 mammary carcinoma model were studied using diffusion-weighted imaging (DWI), immediately followed by wick-in-needle IFP measurement. Voxelwise analysis was conducted with a conventional monoexponential diffusion model, as well as a biexponential model taking IVIM into account. There was no significant correlation of IFP with either the median apparent diffusion coefficient from the monoexponential model (r = 0.11, p = 0.78) or the median tissue diffusivity from the biexponential model (r = 0.30, p = 0.44). However, IFP was correlated with the median pseudo-diffusivity (D(p)) of apparent vascular voxels (r = 0.76, p = 0.02) and with the median product of the perfusion fraction and pseudo-diffusivity (f(p)D(p)) of apparent vascular voxels (r = 0.77, p = 0.02). Although the effect of IVIM in tumors has been reported previously, to our knowledge, this study represents the first direct comparison of IVIM metrics with IFP, with the results supporting the feasibility of the use of IVIM DWI metrics as noninvasive biomarkers for tumor IFP.

Diffusion-weighted imaging plays important roles in cancer diagnosis, monitoring, and treatment. Although most applications measure restricted diffusion by tumor cellularity, diffusion-weighted imaging is also sensitive to vascularity through the intravoxel incoherent motion effect. Hypervascularity can confound apparent diffusion coefficient measurements in breast cancer. We acquired multiple b-value diffusion-weighted imaging at 3 T in a cohort of breast cancer patients and performed biexponential intravoxel incoherent motion analysis to extract tissue diffusivity (Dt), perfusion fraction (fp), and pseudodiffusivity (Dp). Results indicated significant differences between normal fibroglandular tissue and malignant lesions in apparent diffusion coefficient mean (±standard deviation) values (2.44 ± 0.30 vs. 1.34 ± 0.39 μm2/msec, P < 0.01) and Dt (2.36 ± 0.38 vs. 1.15 ± 0.35 μm2/msec, P < 0.01). Lesion diffusion-weighted imaging signals demonstrated biexponential character in comparison to monoexponential normal tissue. There is some differentiation of lesion subtypes (invasive ductal carcinoma vs. other malignant lesions) with fp (10.5 ± 5.0% vs. 6.9 ± 2.9%, P = 0.06), but less so with Dt (1.14 ± 0.32 μm2/msec vs. 1.18 ± 0.52 μm2/msec, P = 0.88) and Dp (14.9 ± 11.4 μm2/msec vs. 16.1 ± 5.7 μm2/msec, P = 0.75). Comparison of intravoxel incoherent motion biomarkers with contrast enhancement suggests moderate correlations. These results suggest the potential of intravoxel incoherent motion vascular and cellular biomarkers for initial grading, progression monitoring, or treatment assessment of breast tumors. Magn Reson Med, 2011. © 2011 Wiley-Liss, Inc.

e12611Background: Accurate assessment of response to neoadjuvant chemotherapy (NAC) is important for surgical planning, particularly in management of the axilla. We evaluated the correlation betwee...

OBJECTIVE. This review article explores recent advancements in PET/MRI for clinical oncologic imaging. CONCLUSION. Radiologists should understand the technical considerations that have made PET/MRI feasible within clinical workflows, the role of PET tracers for imaging various molecular targets in oncology, and advantages of hybrid PET/MRI compared with PET/CT. To facilitate this understanding, we discuss clinical examples (including gliomas, breast cancer, bone metastases, prostate cancer, bladder cancer, gynecologic malignancy, and lymphoma) as well as future directions, challenges, and areas for continued technical optimization for PET/MRI.

Purpose To evaluate the relationship between mammographic breast density (MBD), background parenchymal enhancement (BPE), and fibroglandular tissue (FGT) in women with breast cancer (BC) and at high risk for developing BC. Methods Our institutional database was queried for patients who underwent mammography and MRI. Results Four hundred three (85%) had BC and 72 (15%) were at high risk. MBD ( P =.0005), BPE ( P P =.02) were all higher in high-risk women compared to the BC group. Conclusions Higher levels of MBD, BPE and FGT are seen in women at higher risk for developing BC when compared to women with BC.

Large cell neuroendocrine carcinoma of the breast (NECB) is an extremely rare type of breast cancer; little is known about effective chemotherapies, and data on pathologic response to treatment are unavailable. We report the case of a 34-years-old woman with large cell NECB with initial clinical and pathologic evidence of treatment response to anthracycline-containing neo-adjuvant therapy. Histologic reassessment early during anthracycline chemotherapy revealed cell death with necrosis of 50% of the tumor cells seen in the biopsy specimen. After completing neo-adjuvant chemotherapy, the patient underwent breast-conserving surgery. Pathologic evaluation of the surgical specimen showed a partial response but margins were positive for residual carcinoma. Despite repeated neo-adjuvant chemotherapy, radiotherapy, and surgical resection, the tumor grew rapidly between surgeries and recurred systemically. Therefore, we review the literature on large cell NECB and its treatment options.

Objective To measure background parenchymal enhancement (BPE) and compare with other contrast enhancement values and diffusion-weighted MRI parameters in healthy and cancerous breast tissue at the clinical level. Materials and methods This HIPAA-compliant, IRB approved retrospective study enrolled 77 patients (38 patients with breast cancer – mean age 51.8 ± 10.0 years; 39 high-risk patients for screening evaluation – mean age 46.3 ± 11.7 years), who underwent contrast-enhanced 3T breast MRI. Contrast enhanced MRI and diffusion-weighted imaging were performed to quantify BPE, lesion contrast enhancement, and apparent diffusion coefficient (ADC) metrics in fibroglandular tissue (FGT) and lesions. Results BPE did not correlate with ADC values. Mean BPE for the lesion-bearing patients was higher (43.9%) compared to that of the high-risk screening patients (28.3%, p = 0.004). Significant correlation (r = 0.37, p Conclusion No significant association was observed between parenchymal or lesion enhancement with conventional apparent diffusion metrics, suggesting that proliferative processes are not co-regulated in cancerous and parenchymal tissue.

To evaluate the influence of temporal sparsity regularization and radial undersampling on compressed sensing reconstruction of dynamic contrast-enhanced (DCE) MRI, using the iterative Golden-angle RAdial Sparse Parallel (iGRASP) MRI technique in the setting of breast cancer evaluation.DCE-MRI examinations of the breast (n = 7) were conducted using iGRASP at 3 Tesla. Images were reconstructed with five different radial undersampling schemes corresponding to temporal resolutions between 2 and 13.4 s/frame and with four different weights for temporal sparsity regularization (λ = 0.1, 0.5, 2, and 6 times of noise level). Image similarity to time-averaged reference images was assessed by two breast radiologists and using quantitative metrics. Temporal similarity was measured in terms of wash-in slope and contrast kinetic model parameters.iGRASP images reconstructed with λ = 2 and 5.1 s/frame had significantly (P 0.05) higher similarity to time-averaged reference images than the images with other reconstruction parameters (mutual information (MI)5%), in agreement with the assessment of two breast radiologists. Higher undersampling (temporal resolution 5.1 s/frame) required stronger temporal sparsity regularization (λ ≥ 2) to remove streaking aliasing artifacts (MI 23% between λ = 2 and 0.5). The difference between the kinetic-model transfer rates of benign and malignant groups decreased as temporal resolution decreased (82% between 2 and 13.4 s/frame).This study demonstrates objective spatial and temporal similarity measures can be used to assess the influence of sparsity constraint and undersampling in compressed sensing DCE-MRI and also shows that the iGRASP method provides the flexibility of optimizing these reconstruction parameters in the postprocessing stage using the same acquired data.

Plants have evolved adaptation mechanisms to sense oxygen deficiency in their environments and make coordinated physiological and structural adjustments to enhance their hypoxic tolerance. To gain insight into how plants respond to low-oxygen stress, gene expression profiling using whole-genome DNA amplicon microarrays was carried out at seven time points over 24 h, in wild-type and transgenic PSAG12:ipt Arabidopsis (Arabidopsis thaliana) plants under normoxic and hypoxic conditions. Transcript levels of genes involved in glycolysis and fermentation pathways, ethylene synthesis and perception, calcium signaling, nitrogen utilization, trehalose metabolism, and alkaloid synthesis were significantly altered in response to oxygen limitation. Analysis based on gene ontology assignments suggested a significant down-regulation of genes whose functions are associated with cell walls, nucleosome structures, water channels, and ion transporters and a significant up-regulation of genes involved in transcriptional regulation, protein kinase activity, and auxin responses under conditions of oxygen shortage. Promoter analysis on a cluster of up-regulated genes revealed a significant overrepresentation of the AtMYB2-binding motif (GT motif), a sugar response element-like motif, and a G-box-related sequence, and also identified several putative anaerobic response elements. Finally, quantitative real-time polymerase chain reactions using 29 selected genes independently verified the microarray results. This study represents one of the most comprehensive analyses conducted to date investigating hypoxia-responsive transcriptional networks in plants.

Previous studies have indicated that Arabidopsis thaliana experienced a genome-wide duplication event shortly before its divergence from Brassica followed by extensive chromosomal rearrangements and deletions. While a large number of the duplicated genes have significantly diverged or lost their sister genes, we found 4222 pairs that are still highly conserved, and as a result had similar functional assignments during the annotation of the genome sequence. Using whole-genome DNA microarrays, we identified 906 duplicated gene pairs in which at least one member exhibited a significant response to oxidative stress. Among these, only 117 pairs were up- or down-regulated in both pairs and many of these exhibited dissimilar patterns of expression. Examination of the expression patterns of PAL1 and PAL2, ACD1 and ACD2, genes coding for two Hsp20s, various P450s, and electron transfer flavoproteins suggests Arabidopsis evolved a number of distinct oxidative stress response mechanisms using similar gene sets following the duplication of its genome.

DCIS is a non-obligate precursor in which epithelial cells with features of cancer reside in and expand otherwise normal appearing mammary ducts and lobules. DCIS increases the relative risk of developing invasive breast cancer (IBC) by up to 10 fold. Treatment of DCIS includes breast conserving surgery (BCS), tumor margins permitting, followed by radiation, or mastectomy. Recently we found that pasireotide, a somatostatin analog inhibitor of IGF-I, was effective in reducing cell proliferation and increasing apoptosis in patients with atypical hyperplasia (AH) and or proliferative disease of the breast. At present there are no recognized medical treatments for DCIS. Here we raise the possibility that pasireotide might also be an effective therapy for some DCIS. To make this determination, 8 patients previously diagnosed with DCIS were treated with pasireotide, 600µg twice daily subcutaneously for a period of 20 days. Lesion size was assessed on DCE-MRIs in 3 planes before and after treatment. Of the eight, two had lesions characterized as low grade DCIS on core biopsy, 4 had intermediate or intermediate to high grade lesions, and two had high grade lesions. After treatment they all had surgical excision biopsies. We also measured proliferation and apoptosis to assess effects of pasireotide by expression of Ki67 and caspase 3. To confirm that the effect of pasireotide was mediated via the IGF-I pathway, p-AKT and p-ERK 1/2 were evaluated. Core and excision samples from 14 untreated patients where used as control. Overall, treatment with pasireotide reduced DCIS lesion size by ≥30% according the RECIST criteria in 4 of 8 patients, as measured by DCE-MRI. Of those, pathology of the surgical excision confirmed that there was no remaining DCIS tissue in the two patients with low grade disease. The two additional lesions that were reduced in size one was intermediate to high grade and the other a high grade DCIS. The remaining 4 patients had tumors that were stable in size. Pasireotide reduced cell proliferation and significantly increased apoptosis in the DCIS lesions. While DCIS is less responsive to pasireotide than AH and proliferative disease, it may nevertheless provide a window of opportunity for treatment and possibly eradication of some low grade or higher grade DCIS as well. The main side effect included hyperglycemia, intestinal discomfort and rash or redness at the injection area. Our data show that hyperglycemia disappears relatively fast after ending treatment with pasireotide. In conclusion, treatment with pasireotide eliminated 2 low grade DCIS lesions, shrunk two higher grade ones and also decreased proliferation and increased apoptosis. Additional evidence in a larger number of patients will be necessary. Citation Format: Irineu Illa-Bochaca, Linda Moy, Julia Smith, Debora Axelrod, Baljit Singh, David L. Kleinberg. Treatment of ductal carcinoma in situ (DCIS) with pasireotide, an IGF-I inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT086. doi:10.1158/1538-7445.AM2017-CT086

Purpose To explore the application of diffusion tensor imaging (DTI) for breast tissue and breast pathologies using a stimulated-echo acquisition mode (STEAM) with variable diffusion times. Materials and Methods In this Health Insurance Portability and Accountability Act-compliant study, approved by the local institutional review board, eight patients and six healthy volunteers underwent an MRI examination at 3 Tesla including STEAM-DTI with several diffusion times ranging from 68.5 to 902.5 ms. A DTI model was fitted to the data for each diffusion time, and parametric maps of mean diffusivity, fractional anisotropy, axial diffusivity, and radial diffusivity were computed for healthy fibroglandular tissue (FGT) and lesions. The median value of radial diffusivity for FGT was fitted to a linear decay to obtain an estimation of the surface-to-volume ratio, from which the radial diameter was calculated. Results For healthy FGT, radial diffusivity presented a linear decay with the square root of the diffusion time resulting in a range of estimated radial diameters from 202 to 496 µm, while axial diffusivity presented a nearly time-independent diffusion. Residual fat signal was reduced at longer diffusion times due to the shorter T1 of fat. Residual fat signal to the overall signal in the healthy volunteers' FGT was found to range from 2.39% to 2.55% (shortest mixing time), and from 0.40% to 0.51% (longest mixing time) for the b500 images. Conclusion The use of variable diffusion times may provide an in vivo noninvasive tool to probe diffusion lengths in breast tissue and breast pathology, and might aid by improving fat suppression at longer diffusion times. Level of Evidence: 2 J. Magn. Reson. Imaging 2017;45:84–93.

Studies suggest that conventional cancer therapies given after immunotherapy (IT) can boost antitumor immunity and possibly improve response rates and progression-free survival. We report two cases of metastatic breast cancer with durable complete responses (CRs) after sequential IT and endocrine therapy. Immune analyses of these long-term disease-free breast cancer patients previously treated with imiquimod (IMQ) suggest in-situ vaccination is achieved by topical application of the TLR-7 agonist directly onto tumors. Furthermore, IT-induced antigen-specific T cells were expanded by subsequent endocrine therapy and correlated with response, persisting > 2 years. Our findings therefore suggest that the induction/boosting of polyfunctional tumor antigen-specific T in response to sequential immune endocrine therapy and detected directly ex-vivo can serve as a peripheral blood biomarker for true clinical benefit. Electronic supplementary material The online version of this article (doi:10.1186/s40425-014-0032-2) contains supplementary material, which is available to authorized users.

Oncologic, reconstructive, and cosmetic breast surgery has evolved in the last 20 years. Familiarity with cutting-edge surgical techniques and their imaging characteristics is essential for radiologic interpretation and may help avert false-positive imaging findings. Novel surgical techniques include skin- and nipple-sparing mastectomies, autologous free flaps, autologous fat grafting, and nipple-areola-complex breast reconstruction. These techniques are illustrated and compared with conventional surgical techniques, including modified radical mastectomy and autologous pedicled flaps. The role of magnetic resonance (MR) imaging in surgical planning, evaluation for complications, and postsurgical cancer detection is described. Breast reconstruction and augmentation using silicone gel-filled implants is discussed in light of the Food and Drug Administration's recommendation for MR imaging screening for "silent" implant rupture 3 years after implantation and every 2 years thereafter. Recent developments in skin incision techniques for reduction mammoplasty are presented. The effects of postsurgical changes on the detection of breast cancer are discussed by type of surgery.

To compare fitting methods and sampling strategies, including the implementation of an optimized b-value selection for improved estimation of intravoxel incoherent motion (IVIM) parameters in breast cancer.Fourteen patients (age, 48.4 ± 14.27 years) with cancerous lesions underwent 3 Tesla breast MRI examination for a HIPAA-compliant, institutional review board approved diffusion MR study. IVIM biomarkers were calculated using "free" versus "segmented" fitting for conventional or optimized (repetitions of key b-values) b-value selection. Monte Carlo simulations were performed over a range of IVIM parameters to evaluate methods of analysis. Relative bias values, relative error, and coefficients of variation (CV) were obtained for assessment of methods. Statistical paired t-tests were used for comparison of experimental mean values and errors from each fitting and sampling method.Comparison of the different analysis/sampling methods in simulations and experiments showed that the "segmented" analysis and the optimized method have higher precision and accuracy, in general, compared with "free" fitting of conventional sampling when considering all parameters. Regarding relative bias, IVIM parameters fp and Dt differed significantly between "segmented" and "free" fitting methods.IVIM analysis may improve using optimized selection and "segmented" analysis, potentially enabling better differentiation of breast cancer subtypes and monitoring of treatment.

Water in its various forms affects passive microwave measurements of the Earth. Current and future satellite based microwave radiometer observing systems collect data during times when dew may be present. In this article, a review of studies dealing with or related to the effect of dew on microwave radiometer observations is conducted. The basic principles involved in dew formation are described, and its magnitude is quantified. Results indicate that dew is unlikely to have a significant effect on passive microwave observations at frequencies of interest for soil moisture remote sensing.

Objective. To define and compare early lesions associated with slipped capital femoral epiphysis (SCFE) on magnetic resonance imaging (MRI), computed tomography (CT) and radiography. Design and patients. Thirteen patients with 15 symptomatic hips due to SCFE underwent radiography and MRI; CT was performed in 12 patients. SCFE was graded on radiographs, head/neck angles and qualitative changes were evaluated on CT, and morphologic/signal abnormalities were determined on MRI. Results. Physeal widening, apparent on T1-weighted MRI, was evident in every case of SCFE, including one presumed “pre-slip.” T2-weighted images demonstrated synovitis and marrow edema but obscured physeal abnormalities. CT head/neck angles ranged from 4–57° for symptomatic to 0–14° for asymptomatic hips. Physeal and metaphyseal changes were variably identified on both radiographs and CT in all cases of SCFE, but not in the pre-slip. Conclusion. MRI clearly delineates physeal changes of both pre-slip and SCFE, and demonstrates very early changes at a time when radiographs and CT may appear normal.

This research examined the parent role as perceived by a large number of parents of school-age children in New Hampshire. The results reveal that these parents readily describe a parent role using the same characteristics that emerge from the research literature. More importantly, the subjects consider each of the six parent role characteristics as differentially important at different stages in children's development. The implications of this research for school psychologists are many, including, for instance, assessment, consultation, and intervention.

A 2.91-billion base pair (bp) consensus sequence of the euchromatic portion of the human genome was generated by the whole-genome shotgun sequencing method. The 14.8-billion bp DNA sequence was generated over 9 months from 27,271,853 high-quality sequence reads (5.11-fold coverage of the genome) from both ends of plasmid clones made from the DNA of five individuals. Two assembly strategies—a whole-genome assembly and a regional chromosome assembly—were used, each combining sequence data from Celera and the publicly funded genome effort. The public data were shredded into 550-bp segments to create a 2.9-fold coverage of those genome regions that had been sequenced, without including biases inherent in the cloning and assembly procedure used by the publicly funded group. This brought the effective coverage in the assemblies to eightfold, reducing the number and size of gaps in the final assembly over what would be obtained with 5.11-fold coverage. The two assembly strategies yielded very similar results that largely agree with independent mapping data. The assemblies effectively cover the euchromatic regions of the human chromosomes. More than 90% of the genome is in scaffold assemblies of 100,000 bp or more, and 25% of the genome is in scaffolds of 10 million bp or larger. Analysis of the genome sequence revealed 26,588 protein-encoding transcripts for which there was strong corroborating evidence and an additional ∼12,000 computationally derived genes with mouse matches or other weak supporting evidence. Although gene-dense clusters are obvious, almost half the genes are dispersed in low G+C sequence separated by large tracts of apparently noncoding sequence. Only 1.1% of the genome is spanned by exons, whereas 24% is in introns, with 75% of the genome being intergenic DNA. Duplications of segmental blocks, ranging in size up to chromosomal lengths, are abundant throughout the genome and reveal a complex evolutionary history. Comparative genomic analysis indicates vertebrate expansions of genes associated with neuronal function, with tissue-specific developmental regulation, and with the hemostasis and immune systems. DNA sequence comparisons between the consensus sequence and publicly funded genome data provided locations of 2.1 million single-nucleotide polymorphisms (SNPs). A random pair of human haploid genomes differed at a rate of 1 bp per 1250 on average, but there was marked heterogeneity in the level of polymorphism across the genome. Less than 1% of all SNPs resulted in variation in proteins, but the task of determining which SNPs have functional consequences remains an open challenge.

To develop a bilateral coil and fat suppressed T1-weighted sequence for 7 Tesla (T) breast MRI.A dual-solenoid coil and three-dimensional (3D) T1w gradient echo sequence with B1+ insensitive fat suppression (FS) were developed. T1w FS image quality was characterized through image uniformity and fat-water contrast measurements in 11 subjects. Signal-to-noise ratio (SNR) and flip angle maps were acquired to assess the coil performance. Bilateral contrast-enhanced and unilateral high resolution (0.6 mm isotropic, 6.5 min acquisition time) imaging highlighted the 7T SNR advantage.Reliable and effective FS and high image quality was observed in all subjects at 7T, indicating that the custom coil and pulse sequence were insensitive to high-field obstacles such as variable tissue loading. 7T and 3T image uniformity was similar (P=0.24), indicating adequate 7T B1+ uniformity. High 7T SNR and fat-water contrast enabled 0.6 mm isotropic imaging and visualization of a high level of fibroglandular tissue detail.7T T1w FS bilateral breast imaging is feasible with a custom radiofrequency (RF) coil and pulse sequence. Similar image uniformity was achieved at 7T and 3T, despite different RF field behavior and variable coil-tissue interaction due to anatomic differences that might be expected to alter magnetic field patterns.

To assess two methods of fat and fibroglandular tissue (FGT) segmentation for measuring breast MRI FGT volume and FGT%, the volume percentage of FGT in the breast, in longitudinal studies.Nine premenopausal women provided one MRI per week for 4 weeks during a natural menstrual cycle for a total of 36 datasets. We compared a fuzzy c-means (FC) and a 3-point Dixon segmentation method for estimation of changes in FGT volume and FGT% across the menstrual cycle. We also assessed whether differences due to changes in positioning each week could be minimized by coregistration, i.e., the application of the breast boundary selected at one visit to images obtained at other visits.FC and Dixon FGT volume were highly correlated (r = 0.93, P0.001), as was FC and Dixon FGT% (r = 0.86, P = 0.01), although Dixon measurements were on average 10-20% higher. Although FGT measured by both methods showed the expected pattern of increase during the menstrual cycle, the magnitude, and for one woman the direction, of change varied according to the method used. Measurements of FGT for coregistered images were in close agreement with those for which the boundaries were determined independently.The method of segmentation of fat and FGT tissue may have an impact on the results of longitudinal studies of changes in breast MRI FGT.

Objectives We conducted a pilot study to identify whether MRI parameters are sensitive to hormone-induced changes in the breast during the natural menstrual cycle and whether changes could also be observed during an oral contraceptive (OC) cycle. Materials and Methods The New York University Langone Medical Center Institutional Review Board approved this HIPAA-compliant prospective study. All participants provided written informed consent. Participants were aged 24-31 years.We measured several non-contrast breast MRI parameters during each week of a single menstrual cycle (among 9 women) and OC cycle (among 8 women). Hormones were measured to confirm ovulation and classify menstrual cycle phase among naturally cycling women and to monitor OC compliance among OC users. We investigated how the non-contrast MRI parameters of breast fibroglandular tissue (FGT), apparent diffusion coefficient (ADC), magnetization transfer ratio (MTR), and transverse relaxation time (T2) varied over the natural and the OC cycles. Results We observed significant increases in MRI FGT% and ADC in FGT, and longer T2 in FGT in the luteal vs. follicular phase of the menstrual cycle. We did not observe any consistent pattern of change for any of the MRI parameters among women using OCs. Conclusions MRI is sensitive to hormone-induced breast tissue changes during the menstrual cycle. Larger studies are needed to assess whether MRI is also sensitive to the effects of exogenous hormones, such as various OC formulations, on the breast tissue of young premenopausal women.

The effective delivery of a therapeutic drug to the core of a tumor is often impeded by physiological barriers, such as the interstitial fluid pressure (IFP). There are a number of therapies that can decrease IFP and induce tumor vascular normalization. However, a lack of a noninvasive means to measure IFP hinders the utilization of such a window of opportunity for the maximization of the treatment response. Thus, the purpose of this study was to investigate the feasibility of using intravoxel incoherent motion (IVIM) diffusion parameters as noninvasive imaging biomarkers for IFP. Mice bearing the 4T1 mammary carcinoma model were studied using diffusion-weighted imaging (DWI), immediately followed by wick-in-needle IFP measurement. Voxelwise analysis was conducted with a conventional monoexponential diffusion model, as well as a biexponential model taking IVIM into account. There was no significant correlation of IFP with either the median apparent diffusion coefficient from the monoexponential model (r = 0.11, p = 0.78) or the median tissue diffusivity from the biexponential model (r = 0.30, p = 0.44). However, IFP was correlated with the median pseudo-diffusivity (D(p)) of apparent vascular voxels (r = 0.76, p = 0.02) and with the median product of the perfusion fraction and pseudo-diffusivity (f(p)D(p)) of apparent vascular voxels (r = 0.77, p = 0.02). Although the effect of IVIM in tumors has been reported previously, to our knowledge, this study represents the first direct comparison of IVIM metrics with IFP, with the results supporting the feasibility of the use of IVIM DWI metrics as noninvasive biomarkers for tumor IFP.

The technical requirements for magnetic resonance imaging (MRI) of the breasts are challenging because high temporal and high spatial resolution are necessary. This article describes the necessary equipment and pulse sequences for performing a high-quality study. Although imaging at 3-Tesla (T) has a higher signal-to-noise ratio, the protocol needs to be modified from the 1.5-T system to provide optimal imaging. The article presents the requirements for performing breast MRI and discusses techniques to ensure high-quality examinations on 1.5-T and 3-T systems.

The purpose of this study is to report further about the statistically significant results from a prospective study, which suggests that fusion of prone F-18 Fluoro-deoxy-glucose (FDG) positron emission tomography (PET) and magnetic resonance (MR) breast scans increases the positive predictive value (PPV) and specificity for patients in whom the MR outcome alone would be nonspecific. Thirty-six women (mean age, 43 years; range, 24-65 years) with 90 lesions detected on MR consented to undergo a FDG-PET scan. Two blinded readers evaluated the MR and the computer tomography (CT) attenuation-corrected prone FDG-PET scans side-by-side, then after the volumes were superimposed (fused). A semiautomatic, landmark-based program was used to perform nonrigid fusion. Pathology and radiologic follow-up were used as the reference standard. The sensitivity, specificity, PPV, negative predictive value (NPV), and accuracy (with 95% confidence intervals) for MR alone, FDG-PET alone, and fused MR and FDG-PET were calculated. The median lesion size measured from the MR was 2.5 cm (range, 0.5-10 cm). Histologically, 56 lesions were malignant, and 15 were benign. Nineteen lesions were benign after 20-47 months of clinical and radiologic surveillance. The sensitivity of MR alone was 95%, FDG-PET alone was 57%, and fusion was 83%. The increase in PPV from 77% in MR alone to 98% when fused and the increase in specificity from 53% to 97% were statistically significant (p0.05). The false-negative rate on FDG-PET alone was 26.7%, and after fusion this number was reduced to 9%. FDG-PET and MR fusions were helpful in selecting which lesion to biopsy, especially in women with multiple suspicious MR breast lesions.

The purpose of this study was to evaluate the usefulness of MRI of the breast in cases in which mammographic or sonographic findings are inconclusive.We retrospectively reviewed images from 115 MRI examinations of the breast performed from 1999 to 2005 for the indication of problem-solving for inconclusive findings on a mammogram. Forty-eight of the 115 women (41.8%) were at high risk. We discerned whether sonography or MRI was used as an adjunctive tool and correlated the findings with those in the pathology database.The equivocal findings most frequently leading to MRI were asymmetry and architectural distortion. No suspicious MRI correlate was found in 100 of 115 cases (87%). These cases were found stable at follow-up mammography or MRI after a mean of 34 months. Fifteen enhancing masses (13%) that corresponded to the mammographic abnormality were seen on MR images. All masses identified at MRI were accurately localized for biopsy, and six malignant lesions were identified. Four of six malignant tumors were seen in one mammographic view only; two were seen on second-look ultrasound images. MRI had a sensitivity of 100% and compared with mammography had significantly higher specificity (91.7% vs 80.7%, p = 0.029), positive predictive value (40% vs 8.7%, p = 0.032), and overall accuracy (92.2% vs 78.3%, p = 0.0052). Eighteen incidental lesions (15.7%) were detected at MRI, and all were subsequently found benign.We found breast MRI to be a useful adjunctive tool when findings at conventional imaging were equivocal. Strict patient selection criteria should be used because of the high frequency of incidental lesions seen on MR images.

We describe a probabilistic approach for supervised learning when we have multiple experts/annotators providing (possibly noisy) labels but no absolute gold standard. The proposed algorithm evaluates the different experts and also gives an estimate of the actual hidden labels. Experimental results indicate that the proposed method is superior to the commonly used majority voting baseline.

The educational objectives for this self-assessment module on the interpretation and clinical applications of breast MRI are for the participant to exercise, self-assess, and improve his or her understanding of the imaging and clinical features of cancer and other breast masses on MRI.

We evaluated the benefit of placing a marker under sonographic guidance at the time of localization to aid in identifying mammographically occult lesions within the specimen at the time of surgical excision and to evaluate margin status.We reviewed 135 sonographically guided needle localizations performed on mammographically occult lesions. Imaging during the localization procedure, marker placement, and specimen radiographs were reviewed, and the findings were correlated with the histopathologic findings.Of the 135 mammographically occult lesions, 77 were localized without marker placement and 58 with marker placement. The 58 localizations with marker placement were for masses with a mean lesion size of 9 mm. Specimen radiography of these lesions showed a marker within the specimen in 56 cases (97%) and visualization of the lesion in only seven cases (12%). Specimen radiography of localizations without marker placement showed visualization of the lesion in 18 cases (23%). Of the 11 malignant lesions (19%) localized with marker placement, none had a positive inked margin, but five (46%) had close margins necessitating reexcision. Of the 26 malignant lesions (34%) localized without marker placement, two (8%) had a positive inked margin, and eight (31%) had close margins necessitating reexcision.At needle localization of breast lesions, marker placement under sonographic guidance is beneficial because it enables immediate confirmation of accurate surgical removal of the localized lesion at surgical excision. Use of marker placement, however, does not reduce the percentage of cases with close margins necessitating reexcision.

Objective The purpose of our study was to describe the clinical features, imaging characteristics, pathologic findings and outcome of microinvasive ductal carcinoma in situ (DCISM). Materials and methods The records of 21 women diagnosed with microinvasive ductal carcinoma in situ (DCISM) from November 1993 to September 2006 were retrospectively reviewed. The clinical presentation, imaging and histopathologic features, and clinical follow-up were reviewed. Results The 21 lesions all occurred in women with a mean age of 56 years (range, 27–79 years). Clinical findings were present in ten (48%): 10 with palpable masses, four with associated nipple discharge. Mean lesion size was 21mm (range, 9–65mm). The lesion size in 62% was 15mm or smaller. Mammographic findings were calcifications only in nine (43%) and an associated or other finding in nine (43%) [mass ( n =7), asymmetry ( n =1), architectural distortion ( n =1)]. Three lesions were mammographically occult. Sonographic findings available in 11 lesions showed a solid hypoechoic mass in 10 cases (eight irregular in shape, one round, one oval). One lesion was not seen on sonography. On histopathologic examination, all lesions were diagnosed as DCISM, with a focus of invasive carcinoma less than or equal to 1mm in diameter within an area of DCIS. Sixteen (76%) lesions were high nuclear grade, four (19%) were intermediate and one was low grade (5%). Sixteen (76%) had the presence of necrosis. Positivity for ER and PR was noted in 75% and 38%. Nodal metastasis was present in one case with axillary lymph node dissection. Mean follow-up time for 16 women was 36 months without evidence of local or systemic recurrence. One patient developed a second primary in the contralateral breast 3 years later. Conclusion The clinical presentation and radiologic appearance of a mass are commonly encountered in DCISM lesions (48% and 57%, respectively), irrespective of lesion size, mimicking findings seen in invasive carcinoma. Despite its potential for nodal metastasis (5% in our series), mean follow-up at 36 months was good with no evidence of local or systemic recurrence at follow-up. Knowledge of these clinical and imaging findings in DCISM lesions may alert the clinician to the possibility of microinvasion and guide appropriate management.

MRI is a sensitive method for detecting invasive breast cancer, but it lacks specificity. To examine the effect of combining PET with MRI on breast lesion characterization, a prototype positioning device was fabricated to allow PET scans to be acquired in the same position as MRI scans—that is, prone. Methods: To test the hypothesis that fusion of 18F-FDG PET and MRI scans improves detection of breast cancer, 23 patients with suspected recurrent or new breast cancer underwent a routine whole-body PET scan, a prone PET scan of the chest, and a routine breast MRI scan. The attenuation-corrected prone PET and MRI datasets were registered twice by different operators. The fusion results were judged for quality by visual inspection and statistical analysis. A joint reading of the MRI and PET scans side by side and integrated images was performed by a nuclear medicine physician and a radiologist. Sensitivity and specificity of MRI and combined MRI and PET scans were calculated on the basis of pathology reports or at least 1 y of clinical and radiologic follow-up. Results: All fusions were verified to be well matched using specific anatomic criteria. A total of 45 lesions was assessed. Lesion size range was 0.6 to 10.0 cm. Of the 44 breasts examined, 29 were suspicious for cancer, of which 15 were found to be positive on surgical excision. In lesion-by-lesion analysis, sensitivity and specificity of MRI alone were 92% and 52%, respectively; after MRI and PET fusion, they were 63% and 95%, respectively. The positive predictive value and the negative predictive value for MRI alone were 69% and 85%, respectively; after MRI and PET fusion, they were 94% and 69%, respectively. Conclusion: Acquisition of prone PET scans using the new positioning device permitted acquisition of prone scans suitable for fusion with breast MRI scans. Fused PET and MRI scans increased the specificity of MRI but decreased the sensitivity in this small group of patients. Additional data are needed to confirm the statistical significance of these preliminary findings.

Purpose: This study compared prone acquisition of PET scans with traditional supine acquisition to improve fusion of PET scans with MRI scans and improve evaluation of enhancing breast lesions detected on MRI. Materials and Methods: MRI breast scans are acquired in the prone position using a breast coil to allow the breasts to hang pendant. An apparatus was fabricated to allow prone acquisition of PET scans. Fused scans from 2 patients acquired both prone and supine were contrasted with those from 3 patients acquired supine only. All 5 MRI scans were acquired on standard scanners. The PET scans were acquired with a PET/CT unit using a low-dose CT scan for attenuation correction. The PET and MRI volumes were matched twice (using a semiautomated registration method) by different operators. The additional value of fusion was judged using reports from the original (nonfused) MRI and PET, joint rereading of the volumes side by side, and examination of fused images. Results: Of 12 enhancing lesions on breast MRI, 7 demonstrated uptake on PET/CT. In the 3 supine-only cases, the fused images were not interpretable because of the marked distortion of the breasts. In the 2 prone cases, the fused images increased our confidence in characterizing a lesion as benign or malignant. Interpretations were confirmed by clinical follow up in 2 or histologic results in 3 patients. Conclusions: PET MRI fusion is feasible and may assist in localizing lesions detected on either study. A more extensive study is under-way to confirm the value of this fusion technique.