Faculty Bibliography

Breast MRI is more sensitive than mammography in detecting breast cancer. However, MRI as a screening tool is limited to high-risk patients due to cost, low specificity and insufficient evidence for its use in intermediate-risk populations. Nonetheless, in the past decade, there has been a dramatic increase in the use of breast-screening MRI in the community setting. In this review, we set to describe the current literature on the use of screening MRI in high- and intermediate-risk populations. We will also describe novel applications of breast MRI including abbreviated breast MRI protocols, background parenchymal enhancement and diffusion-weighted imaging.

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.

OBJECTIVE. Background parenchymal enhancement (BPE) refers to enhancing fibroglandular tissue on initial contrast-enhanced MR images. BPE appears to impact the rate of abnormal MRI interpretation and may correlate with breast cancer risk. There are now minimal data as to the uniformity of radiologists' BPE assessments and no data as to whether training improves agreement. Therefore, for this study, we sought to assess interreader agreement for BPE at baseline and after dedicated training. MATERIALS AND METHODS. This study included 119 breast MRI examinations performed in 119 patients (mean age, 47 years; age range, 25-79 years) in 2008. One week before training, four fellowship-trained breast imagers with 2-12 years' experience independently recorded BPE on a 4-point scale as follows: 1 (minimal, 75%). The same 119 cases were reread in a new random order within 1 week and at least 3 weeks after training. Interreader agreement and intrareader agreement were assessed using kappa coefficients. RESULTS. With training, interreader agreement increased from fair (kappa = 0.36) to moderate (kappa = 0.48). Improvement was sustained at 3 weeks after training (kappa = 0.45). Intrareader agreement between time points 2 and 3 (kappa: mean, 0.79; range, 0.56-0.98) was greater than between time points 1 and 2 (kappa: mean, 0.62; range, 0.45-0.84), indicating readers learned and retained. CONCLUSION. Initial interreader agreement for BPE was fair among breast radiologists but achieved sustained improvement with training, highlighting the importance of education and inclusion of standardized BPE categories in a reference atlas.

OBJECTIVE: To determine the utility of short-interval follow-up after benign concordant MRI-guided breast biopsy. MATERIALS AND METHODS: Institutional review board approved, retrospective review of consecutive biopsies performed over 3 years (2007-10) yielded 170 women with 188 lesions that were considered benign concordant. Indication for original study, biopsy results, follow-up recommendations, compliance and outcomes of subsequent MRI and mammography examinations were reviewed. RESULTS: The most common indication for breast MRI was high-risk screening 119/170 (70 %). Overall, 59 % of lesions (113/188) had follow-up MRI. Of those lesions (n = 113), 43 % (49/113) presented within 7 months, 26 % (29/113) presented within 8-13 months, 11.5 % (13/113) presented within 14-22 months, and 19 % (22/113) presented after 23 months. At initial follow-up, 37 % of lesions were stable and 61 % were decreased in size. Three lesions were recommended for excision based on follow-up imaging with one malignancy diagnosed 2 years following biopsy. One additional patient had MRI-detected bilateral cancers remote from the biopsy site 3 years after biopsy. CONCLUSION: Overall cancer yield of lesions with follow-up MRI was 0.9 % (1/113); no cancers were detected at 6 months. Our data suggests that 6-month follow-up may not be required and that annual screening MRI would be acceptable to maintain a reasonable cancer detection rate. KEY POINTS: * Follow-up recommendations after benign concordant MRI-guided breast biopsy remain controversial. * Cancer detection rate was 0.9 % overall with no cancers detected at 6 months. * Short-interval follow-up after benign concordant MRI-guided breast biopsy may not be necessary.

With the increasing use of breast magnetic resonance (MR) imaging comes the expectation that the breast radiologist is as fluent in its interpretation as in that of mammography and breast ultrasonography. Knowledge of who should be included for imaging and how to perform the imaging are as essential as interpreting the images. When reading the examination, the radiologist should approach the images from both a global and focused perspective, synthesizing findings into a report that includes a management plan. This article reviews a systematic and organized approach to breast MR imaging interpretation.

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. (c)RSNA, 2014.

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 2013. (c) 2013 Wiley Periodicals, Inc.

OBJECTIVE. The purposes of this study were to determine the frequency of underestimation of high-risk lesions at MRI-guided 9-gauge vacuum-assisted breast biopsy and to determine the imaging and demographic characteristics predictive of lesion upgrade after surgery. MATERIALS AND METHODS. We retrospectively reviewed consecutively detected lesions that were found only at MRI and biopsied under MRI guidance from May 2007 to April 2012. Imaging indications, imaging features, and histologic findings were reviewed. The Fisher exact test was used to assess the association between characteristics and lesion upgrade. Patients lost to follow-up or who underwent mastectomy were excluded, making the final study cohort 140 women with 151 high-risk lesions, 147 of which were excised. RESULTS. A database search yielded the records of 1145 lesions in 1003 women. Biopsy yielded 252 (22.0%) malignant tumors, 184 (16.1%) high-risk lesions, and 709 (61.9%) benign lesions. Thirty of the 147 (20.4%) excised high-risk lesions were upgraded to malignancy. The upgrade rate was highest for atypical ductal hyperplasia, lobular carcinoma in situ, and radial scar. No imaging features were predictive of upgrade. However, there was a significantly higher risk that a high-risk lesion would be upgraded to malignancy if the current MRI-detected high-risk lesion was in the same breast as a malignant tumor previously identified in the remote history, a recently diagnosed malignant tumor, or a high-risk lesion previously identified in the remote history (p = 0.0001). The upgrade rate was significantly higher for women with a personal cancer history than for other indications combined (p = 0.0114). CONCLUSION. The rate of underestimation of malignancy in our series was 20%. No specific imaging features were seen in upgraded cases. Surgical excision is recommended for high-risk lesions found at MRI biopsy and may be particularly warranted for women with a personal history of breast cancer.