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ABSTRACT: To achieve high-quality unilateral supine breast magnetic resonance imaging (MRI) as a step to facilitate image aiding of clinical applications, which are often performed in the supine position. Contrast-enhanced breast MRI is a powerful tool for the diagnosis of cancer. However, prone patient positioning typically used for breast MRI hinders its use for image aiding.
A fixture and a flexible four-element receive coil were designed for patient-specific shaping and placement of the coil in close conformity to the supine breast. A 3D spoiled gradient sequence was modified to incorporate compensation of respiratory motion. The entire setup was tested in volunteer experiments and in a pilot patient study.
The flexible coil design and the motion compensation produced supine breast MR images of high diagnostic value. Variations in breast shape and in tissue morphology within the breast were observed between a supine and a diagnostic prone MRI of a patient.
The presented supine breast MRI achieved an image quality comparable to diagnostic breast MRI. Since supine positioning is common in many clinical applications such as ultrasound-guided breast biopsy or breast-conserving surgery, the registration of the supine images will aid these applications.
Journal of Magnetic Resonance Imaging 09/2011; 34(5):1212-7. · 2.70 Impact Factor
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Ellen Warner,
Kimberley Hill, Petrina Causer,
Donald Plewes,
Roberta Jong,
Martin Yaffe,
William D Foulkes,
Parviz Ghadirian,
Henry Lynch,
Fergus Couch,
John Wong,
Frances Wright,
Ping Sun,
Steven A Narod
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ABSTRACT: The sensitivity of magnetic resonance imaging (MRI) for breast cancer screening exceeds that of mammography. If MRI screening reduces mortality in women with a BRCA1 or BRCA2 mutation, it is expected that the incidence of advanced-stage breast cancers should be reduced in women undergoing MRI screening compared with those undergoing conventional screening.
We followed 1,275 women with a BRCA1 or BRCA2 mutation for a mean of 3.2 years. In total, 445 women were enrolled in an MRI screening trial in Toronto, Ontario, Canada, and 830 were in the comparison group. The cumulative incidences of ductal carcinoma in situ (DCIS), early-stage, and late-stage breast cancers were estimated at 6 years in the cohorts.
There were 41 cases of breast cancer in the MRI-screened cohort (9.2%) and 76 cases in the comparison group (9.2%). The cumulative incidence of DCIS or stage I breast cancer at 6 years was 13.8% (95% CI, 9.1% to 18.5%) in the MRI-screened cohort and 7.2% (95% CI, 4.5% to 9.9%) in the comparison group (P = .01). The cumulative incidence of stages II to IV breast cancers was 1.9% (95% CI, 0.2% to 3.7%) in the MRI-screened cohort and 6.6% (95% CI, 3.8% to 9.3%) in the comparison group (P = .02). The adjusted hazard ratio for the development of stages II to IV breast cancer associated with MRI screening was 0.30 (95% CI, 0.12 to 0.72; P = .008).
Annual surveillance with MRI is associated with a significant reduction in the incidence of advanced-stage breast cancer in BRCA1 and BRCA2 carriers.
Journal of Clinical Oncology 03/2011; 29(13):1664-9. · 18.37 Impact Factor
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ABSTRACT: Breast MRI is often used for surveillance of breast cancer (BC) survivors despite the lack of evidence in this population. We surveyed younger BC survivors to evaluate their willingness to participate in a randomized controlled trial (RCT) of annual digital mammography with or without MRI. Median age of the 348 participants was 51 years; 45% had undergone diagnostic MRI. 22% continued to have surveillance MRI. 58% agreed to consider participating in the proposed RCT; 16% remained neutral. An RCT of MRI surveillance for BC survivors <age 60 is still feasible at centres where annual MRI is not yet routinely recommended.
Breast (Edinburgh, Scotland) 02/2011; 20(1):96-8. · 2.09 Impact Factor
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ABSTRACT: To evaluate the effect that variations in the enhancement threshold have on the diagnostic accuracy of two computer-aided detection (CAD) systems for magnetic resonance based breast cancer screening.
Informed consent was obtained from all patients participating in cancer screening and this study was approved by the participating institution's review board. This retrospective study was nested in a prospective, single-institution, high-risk, breast screening study involving dynamic contrast-enhanced magnetic resonance imaging. Only those screening examinations (n = 223) for which a histopathological diagnosis was available were included. Two CAD methods were performed: the signal enhancement ratio (SER) and support vector machines (SVMs). Statistical analysis was performed by tracking changes in each CAD test's diagnostic accuracy (eg, receiver-operating characteristic [ROC] curve area, maximum possible sensitivity) with changes in the enhancement threshold.
The enhancement threshold plays a significant role in affecting a CAD test's potential sensitivity, ROC curve area, and number of assumed true and false-positive predictions per cancerous examination. A high threshold can also limit the CAD-based detection of the full size of a lesion.
Enhancement thresholds can limit a CAD test's ability to diagnose a lesion's full size and as such should not be raised above 60%. The clinically used SER method exhibits a high rate of false positives at low enhancement thresholds and as such the threshold should not be set lower than 50%. The SVM method yielded better results in our study than the SER method at clinically realistic enhancement thresholds.
Academic radiology 07/2009; 16(9):1064-9. · 2.09 Impact Factor
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ABSTRACT: Breast magnetic resonance imaging (MRI) may provide a more accurate assessment of synchronous contralateral breast cancer in select cohorts of patients. The utility of this imaging technique for detecting synchronous contralateral breast cancers in patients with locally advanced breast cancer (LABC) has not previously been described. We report our experience in assessing contralateral disease in a cohort of women with LABC who had clinical assessment, mammography, ultrasound, and MRI prior to neo-adjuvant therapy. Patients, who presented with LABC, stage IIB (T3N0), stage III A/B, were identified from a prospectively kept data base at a single tertiary care centre between November 2001 and August 2005. Charts were retrospectively reviewed and demographic, imaging and pathologic variables were abstracted. One hundred and one female patients with LABC were identified (median age 49). One hundred of 101 patients presented with a clinically obvious LABC. Three patients had LABC that was not visualized mammographically but was detected on ultrasound and MRI. Seventeen of 101 patients (17%) had contralateral imaging findings that required biopsy for diagnosis. Of the contralateral biopsies, 41% (7/17) were malignant. These malignant lesions were identified clinically in 4/7 patients, on 7/7 ultrasounds, 7/7 mammograms, and 5/5 MRI. Overall, 7% (7/101) patients had malignant synchronous contralateral disease. In our LABC patient cohort, 7% of patients presented with malignant contralateral disease. The incidence of contralateral disease in women with LABC is comparable with patients who present with early stage breast cancer. No single screening technique, ultrasound, mammogram or MRI, appeared to be superior for identifying contralateral synchronous malignancy.
The Breast Journal 11/2008; 14(6):556-61. · 1.64 Impact Factor
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ABSTRACT: A sensitive and acceptable screening regimen for women at high risk for breast cancer is essential. Contrast-enhanced magnetic resonance imaging (MRI) of the breast is highly sensitive for diagnosis of breast cancer but has variable specificity.
To summarize the sensitivity, specificity, likelihood ratios, and posttest probability associated with adding MRI to annual mammography screening of women at very high risk for breast cancer.
English-language literature search of the MEDLINE, EMBASE, and Cochrane databases from January 1995 to September 2007, supplemented by hand searches of pertinent articles.
Prospective studies published after 1994 in which MRI and mammography (with or without additional tests) were used to screen women at very high risk for breast cancer.
Methods and potential biases of studies were assessed by 2 reviewers, and data were extracted and entered into 2 x 2 tables that compared American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) scores of MRI plus mammography, mammography alone, or MRI alone with results of breast tissue biopsies.
Eleven relevant, prospective, nonrandomized studies that ranged from small single-center studies with only 1 round of patient screening to large multicenter studies with repeated rounds of annual screening were identified. Characteristics of women that varied across study samples included age range, history of breast cancer, and BRCA1 or BRCA2 mutation status. Studies used dynamic contrast-enhanced MRI with axial or coronal plane images (European studies) or sagittal images (North American studies) that were usually interpreted without knowledge of mammography results. The summary negative likelihood ratio and the probability of a BI-RADS-suspicious lesion (given negative test findings and assuming a 2% pretest probability of disease) were 0.70 (95% CI, 0.59 to 0.82) and 1.4% (CI, 1.2% to 1.6%) for mammography alone and 0.14 (CI, 0.05 to 0.42) and 0.3% (CI, 0.1% to 0.8%) for the combination of MRI plus mammography, using a BI-RADS score of 4 or higher as the definition of positive.
Differences in patient population, center experience, and criteria for positive screening results led to between-study heterogeneity. Data on patients with nonfamilial high risk were limited, and no data were available on recurrence or survival.
Screening with both MRI and mammography might rule out cancerous lesions better than mammography alone in women who are known or likely to have an inherited predisposition to breast cancer.
Annals of internal medicine 06/2008; 148(9):671-9. · 16.73 Impact Factor
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IEEE Trans. Med. Imaging. 01/2008; 27:688-696.
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Mitchell D Schnall,
Jeffrey Blume,
David A Bluemke,
Gia A DeAngelis,
Nanette DeBruhl,
Steven Harms,
Sylvia H Heywang-Köbrunner,
Nola Hylton,
Christiane K Kuhl,
Etta D Pisano, Petrina Causer,
Stuart J Schnitt,
David Thickman,
Carol B Stelling,
Paul T Weatherall,
Constance Lehman,
Constantine A Gatsonis
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ABSTRACT: To prospectively determine the prevalence and predictive value of three-dimensional (3D) and dynamic breast magnetic resonance (MR) imaging and contrast material kinetic features alone and as part of predictive diagnostic models.
The study protocol was approved by the institutional review board or ethics committees of all participating institutions, and informed consent was obtained from all participants. Although study data collection was performed before HIPAA went into effect, standards that would be compliant with HIPAA were adhered to. Data from the International Breast MR Consortium trial 6883 were used in the analysis. Women underwent 3D (minimum spatial resolution, 0.7 x 1.4 x 3 mm; minimal temporal resolution, 4 minutes) and dynamic two-dimensional (temporal resolution, 15 seconds) MR imaging examinations. Readers rated enhancement shape, enhancement distribution, border architecture, enhancement intensity, presence of rim enhancement or internal septations, and the shape of the contrast material kinetic curve. Regression was performed for each feature individually and after adjustment for associated mammographic findings. Multivariate models were also constructed from multiple architectural and dynamic features. Areas under the receiver operating characteristic curve (Az values) were estimated for all models.
There were 995 lesions in 854 women (mean age, 53 years +/- 12 [standard deviation]; range, 18-80 years) for whom pathology data were available. The absence of enhancement was associated with an 88% negative predictive value for cancer. Qualitative characterization of the dynamic enhancement pattern was associated with an Az value of 0.66 across all lesion architectures. Focal mass margins (Az = 0.76) and signal intensity (Az = 0.70) were highly predictive imaging features. Multivariate models were constructed with an Az value of 0.880.
Architectural and dynamic features are important in breast MR imaging interpretation. Multivariate models involving feature assessment have a diagnostic accuracy superior to that of qualitative characterization of the dynamic enhancement pattern.
Radiology 02/2006; 238(1):42-53. · 5.73 Impact Factor
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Mitchell D Schnall,
Jeffery Blume,
David A Bluemke,
Gia A Deangelis,
Nanette Debruhl,
Steven Harms,
Sylvia H Heywang-Köbrunner,
Nola Hylton,
Christiane K Kuhl,
Etta D Pisano, Petrina Causer,
Stuart J Schnitt,
Stanley F Smazal,
Carol B Stelling,
Constance Lehman,
Paul T Weatherall,
Constantine A Gatsonis
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ABSTRACT: Prior single institution studies suggest MRI may improve the assessment of the extent of cancer within the breast, and thus reduce the risk of leaving macroscopic disease in the breast following breast conservation therapy. We report on the rate of MRI and mammography detection of foci of distinct incidental cancer in a prospective, multi center trial involving 426 women with confirmed breast cancer at 15 institutions in the US, Canada, and Germany.
Women underwent mammography and MRI prior to biopsy of the suspicious index lesion. Additional incidental lesions (IL) greater than 2 cm from the index lesion that were detected by mammography and MRI were noted and characterized. Biopsy recommendations were associated with ILs given an assessment of suspicious or highly suspicous (BiRads 4 and 5). These assessments were considered a positive test.
MRI had a significantly higher yield of confirmed cancer ILs than mammography (0.18 (95%CI: 0.142-0.214) for MRI versus 0.072 (95%CI: 0.050-0.100) for mammography). The cancer ILs detected by MRI alone appeared to be similar to those detected by mammography with respect to size and histology. The percentage of biopsies of ILs that resulted in a cancer diagnosis was similar between the modalities (MRI 0.72(95%CI: 0.6-0.81); Mammography 0.85 (95%CI: 0.62-0.96)).
These results suggest that consideration needs to be given regarding the integration of breast MRI into the pretreatment evaluation of women seeking breast conservation therapy.
Journal of Surgical Oncology 11/2005; 92(1):32-8. · 2.10 Impact Factor
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David A Bluemke,
Constantine A Gatsonis,
Mei Hsiu Chen,
Gia A DeAngelis,
Nanette DeBruhl,
Steven Harms,
Sylvia H Heywang-Köbrunner,
Nola Hylton,
Christiane K Kuhl,
Constance Lehman,
Etta D Pisano, Petrina Causer,
Stuart J Schnitt,
Stanley F Smazal,
Carol B Stelling,
Paul T Weatherall,
Mitchell D Schnall
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ABSTRACT: Breast magnetic resonance imaging (MRI) has been shown to have high sensitivity for cancer detection and is increasingly used following mammography to evaluate suspicious breast lesions.
To determine the accuracy of breast MRI in conjunction with mammography for the detection of breast cancer in patients with suspicious mammographic or clinical findings.
Prospective multicenter investigation of the International Breast MR Consortium conducted at 14 university hospitals in North America and Europe from June 2, 1998, through October 31, 2001, of 821 patients referred for breast biopsy for American College of Radiology category 4 or 5 mammographic assessment or suspicious clinical or ultrasound finding.
MRI examinations performed prior to breast biopsy; MRI results were interpreted at each site, which were blinded to pathological results.
Area under the receiver operating characteristic curve (AUC), sensitivity, and specificity of breast MRI.
Among the 821 patients, there were 404 malignant index lesions, of which 63 were ductal carcinoma in situ (DCIS) and 341 were invasive carcinoma. Of the 417 nonmalignant index lesions, 366 were benign, 47 showed atypical histology, and 4 were lobular carcinoma in situ. The AUC pooled over all institutions was 0.88 (95% confidence interval [CI], 0.86-0.91). MRI correctly detected cancer in 356 of 404 cancer cases (DCIS or invasive cancer), resulting in a sensitivity of 88.1% (95% CI, 84.6%-91.1%), and correctly identified as negative for cancer 281 of 417 cases without cancer, resulting in a specificity of 67.7% (95% CI, 62.7%-71.9%). MRI performance was not significantly affected by mammographic breast density, tumor histology, or menopausal status. The positive predictive values for 356 of 492 patients was 72.4% (95% CI, 68.2%-76.3%) and of mammography for 367 of 695 patients was 52.8% (95% CI, 49.0%-56.6%) (P<.005). Dynamic MRI did not improve the AUC compared with 3-dimensional MRI alone, but the specificity of a washout pattern for 123 of 136 patients without cancer was 90.4% (95% CI, 84%-95%).
Breast MRI has high sensitivity but only moderate specificity independent of breast density, tumor type, and menopausal status. Although the positive predictive value of MRI is greater than mammography, MRI does not obviate the need for subsequent tissue sampling in this setting.
JAMA The Journal of the American Medical Association 01/2005; 292(22):2735-42. · 30.03 Impact Factor
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IEEE Trans. Med. Imaging. 01/2003; 22:1100-1110.
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ABSTRACT: Tamoxifen citrate therapy increases the prevalence of benign and malignant uterine lesions. At transvaginal ultrasonography (US), the finding of a thickened central endometrial complex, with or without cystic changes, is often nonspecific and may be caused by an endometrial polyp, submucosal leiomyoma (fibroid), endometrial hyperplasia, carcinoma, or cystic atrophy. In addition, because of an increased prevalence of adenomyosis or adenomyosis-like changes in women receiving tamoxifen, proper transvaginal US assessment of endometrial thickness and abnormalities is difficult in some women. Hysterosonography, as an adjunct to transvaginal US, allows identification of intracavitary lesions and focal and diffuse endometrial abnormalities and helps determine whether an abnormality is endometrial or subendometrial. Endometrial polyps may be seen at transvaginal US as nonspecific thickening of the endometrial complex, with or without cystic changes. At hysterosonography, they appear as an echogenic mass with smooth margins. Submucosal leiomyomas may protrude into the endometrial cavity, causing false endometrial thickening at transvaginal US. Hysterosonography shows a round structure arising from the myometrium with a thin, overlying endometrium. At transvaginal US, when the endometrium cannot be accurately measured or when there is a nonspecific thickened central endometrial complex, hysterosonography can provide additional information and can help in the triage for hysteroscopic versus nondirected endometrial biopsy. Correlation of transvaginal US and hysterosonographic findings with hysteroscopic and pathologic findings enhances understanding of these changes, as well as the limitations and potential pitfalls of both imaging techniques.
Radiographics 23(1):137-50; discussion 151-5. · 2.85 Impact Factor
