Suspicious Enhancement Research Articles

Benign pericholecystic regeneration mimicking hepatocellular carcinoma: a potential pitfall in imaging of cirrhosis.

Several pseudolesions mimicking malignancy have been reported in cirrhotic and non-cirrhotic livers. Pericholecystic regeneration is among those pseudolesions and can occasionally mimic malignancy. Herein we present a case series comprised of 10 cirrhotic patients (majority due to alcoholic liver disease [ALD] or metabolic dysfunction associated steatotic liver disease [MASLD]) with pericholecystic observations initially categorized as highly suspicious for HCC (LR-4 and LR-5) due to their suspicious enhancement pattern which were later proven to be benign based on biopsy, transplantation or imaging criteria (stability of size and morphology on serial CT or MRI for > 2 years). These observations ranged 2-6.3cm in size, were multiple in most patients and universally resulted in indentations of gallbladder. Arterial phase hyperenhancement and washout, features usually attributed to hepatocellular carcinoma (HCC), were seen in most patients. However, ancillary features of malignancy such as diffusion restriction, increased T2 signal, and hypointensity on hepatobiliary phase MRI were not present. Pericholecystic observations, in particular in the setting of ALD and MASLD, should be carefully assessed and possibility of pseudolesion should be considered especially when the observations are multiple, cause indentation of gallbladder, and lack ancillary features of malignancy.

Abstract PO3-07-06: Correlation between residual microcalcification and in-breast pathologic response in relation to MRI response and the subtypes after neoadjuvant chemotherapy

Abstract Background The significance of residual microcalcifications after neoadjuvant chemotherapy (NAC) in determining the extent of surgical intervention in breast cancer remains unclear. This study aimed to assess whether residual microcalcifications after NAC correlate with the residual disease in patients with breast cancer stratified by subtypes, particularly in excellent radiologic responders. Methods We conducted a retrospective study of patients with breast cancer who underwent NAC followed by curative surgery between January 2007 and December 2022. We evaluated the presence of suspicious microcalcifications on pre-NAC mammography and residual microcalcifications on post-NAC mammography. In the patients who had residual microcalcifications on post-NAC mammography, the rates of breast pathologic complete response (pCR), defined as the absence of invasive cancer (ypT0/is) or complete breast pCR defined as the absence of invasive cancer and in-situ cancer in the breast (ypT0), was assessed according to the MRI response and subtypes. We defined complete MRI response as the resolution of suspicious enhancement in the breast and axilla after NAC. Results Of the 1078 patients, 554 (51.4%) had suspicious microcalcifications at baseline, of which 518 (93.5%) had residual microcalcifications after NAC. Among the 518 patients with residual microcalcifications, 93 (18.0%) achieved a complete MRI response. We observed a difference in breast pCR rates depending on MRI response and hormone-receptor (HR) status. In the patients without complete MRI response, about one-third of patients (139 of 425 [32.7%]) achieved a breast pCR, irrespective of HR status (19.3% [47 of 244] in HR-positive breast cancer and 50.8% [92 of 181] in HR- negative breast cancer). Of the 93 patients who achieved a complete MRI response, the breast pCR rates were 64.3% (27 of 42) in HR-positive breast cancer and 96.1% (49 of 51) in HR-negative breast cancer, respectively. Moreover, the breast complete pCR rate was 54.8% (23 of 51) in HR-positive breast cancer and 88.2% (45 of 51) in HR-negative breast cancer, including 87.2% (34 of 39) in HR-HER2+ breast cancer and 91.7% (11 of 12) in triple-negative breast cancer. Conclusion Our results suggest that the clinical relevance of the residual microcalcifications differs according to the breast cancer subtypes. For patients with HR-positive breast cancer, removal of the residual microcalcifications should be considered to ensure complete cancer removal, regardless of MRI response. In contrast, de-escalating surgery may be considered in patients with HR-negative breast cancer who achieve complete MRI response after NAC. Citation Format: Soong June Bae, Seung Ho Baek, Seung Eun Lee, Min Ji Kim, Sohyun Moon, Junghyun Kim, Yoonwon Kook, Joon Jeong, Sung Gwe Ahn. Correlation between residual microcalcification and in-breast pathologic response in relation to MRI response and the subtypes after neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-07-06.

Radiologic-Pathologic Correlation of Nonmass Enhancement Contiguous with Malignant Index Breast Cancer Masses at Preoperative Breast MRI.

Purpose To determine the pathologic features of nonmass enhancement (NME) directly adjacent to biopsy-proven malignant masses (index masses) at preoperative MRI and determine imaging characteristics that are associated with a malignant pathologic condition. Materials and Methods This retrospective study involved the review of breast MRI and mammography examinations performed for evaluating disease extent in patients newly diagnosed with breast cancer from July 1, 2016, to September 30, 2019. Inclusion criteria were limited to patients with an index mass and the presence of NME extending directly from the mass margins. Wilcoxon rank sum test, Fisher exact test, and χ2 test were used to analyze cancer, patient, and imaging characteristics associated with the NME diagnosis. Results Fifty-eight patients (mean age, 58 years ± 12 [SD]; all women) were included. Malignant pathologic findings for mass-associated NME occurred in 64% (37 of 58) of patients, 43% (16 of 37) with ductal carcinoma in situ and 57% (21 of 37) with invasive carcinoma. NME was more likely to be malignant when associated with an index cancer that had a low Ki-67 index (<20%) (P = .04). The presence of calcifications at mammography correlating with mass-associated NME was not significantly associated with malignant pathologic conditions (P = .19). The span of suspicious enhancement measured at MRI overestimated the true span of disease at histologic evaluation (P < .001), while there was no evidence of a difference between span of calcifications at mammography and true span of disease at histologic evaluation (P = .27). Conclusion Mass-associated NME at preoperative MRI was malignant in most patients with newly diagnosed breast cancer. The span of suspicious enhancement measured at MRI overestimated the true span of disease found at histologic evaluation. Keywords: Breast, Mammography © RSNA, 2024 See also the commentary by Newell in this issue.

Breast MRI in patients with implantable loop recorder: initial experience.

To investigate the feasibility of breast MRI exams and guided biopsies in patients with an implantable loop recorder (ILR) as well as the impact ILRs may have on image interpretation. This retrospective study examined breast MRIs of patients with ILR, from April 2008 to September 2022. Radiological reports and electronic medical records were reviewed for demographic characteristics, safety concerns, and imaging findings. MR images were analyzed and compared statistically for artifact quantification on the various pulse sequences. Overall, 40/82,778 (0.049%) MRIs during the study period included ILR. All MRIs were completed without early termination. No patient-related or device-related adverse events occurred. ILRs were most commonly located in the left lower-inner quadrant (64.6%). The main artifact was a signal intensity (SI) void in a dipole formation in the ILR bed with or without areas of peripheral high SI. Artifacts appeared greatest in the cranio-caudal axis (p < 0.001), followed by the anterior-posterior axis (p < 0.001), and then the right-left axis. High peripheral rim-like SI artifacts appeared on the post-contrast and subtracted T1-weighted images, mimicking suspicious enhancement. Artifacts were most prominent on diffusion-weighted (p < 0.001), followed by T2-weighted and T1-weighted images. In eight patients, suspicious findings were found on MRI, resulting in four additional malignant lesions. Of six patients with left breast cancer, the tumor was completely visible in five cases and partially obscured in one. Breast MRI is feasible and safe among patients with ILR and may provide a significant diagnostic value, albeit with localized, characteristic artifacts. Indicated breast MRI exams and guided biopsies can be safely performed in patients with implantable loop recorder. Nevertheless, radiologists should be aware of associated limitations including limited assessment of the inner left breast and pseudo-enhancement artifacts. • Breast MRI in patients with an implantable loop recorder is an infrequent, feasible, and safe procedure. • Despite limited breast visualization of the implantable loop recorder bed and characteristic artifacts, MRI depicted additional lesions in 8/40 (20%) of cases, half of which were malignant. • Breast MRI in patients with an implantable loop recorder should be performed when indicated, taking into consideration typical associated artifacts.

Challenging Contrast-Enhanced Mammography-Guided Biopsies: Practical Approach Using Real-Time Multimodality Imaging and a Proposed Procedural Algorithm.

Contrast-enhanced mammography (CEM) is an emerging functional breast imaging technique that entails the acquisition of dual-energy digital mammographic images after IV administration of iodine-based contrast material. CEM-guided biopsy technology was introduced in 2019 and approved by the U.S. FDA in 2020. This technology's availability enables direct sampling of suspicious enhancement seen only on or predominantly on recombined CEM images and addresses a major obstacle to the clinical implementation of CEM technology. The literature describing clinical indications and procedural techniques of CEM-guided biopsy is scarce. This article describes our initial experience in performing challenging CEM-guided biopsies and proposes a step-by-step procedural algorithm designed to proactively address anticipated technical difficulties and thereby increase the likelihood of achieving successful targeting.

Implementation of abbreviated breast MRI in diagnostic and screening settings.

Abbreviated magnetic resonance imaging (MRI) includes fewer sequences than standard MRI, which could be utilized for breast cancer detection. To evaluate the diagnostic accuracy of abbreviated MRI protocol in screening and diagnostic settings. All women with screening and diagnostic (problem-solving and preoperative staging) MRI examination were recruited from 2017 to 2020. Two expert radiologists assessed designed abbreviated protocol (fat-saturated T1-weighted [T1W] pre-contrast and two first fat-saturated T1W post-contrast series with reconstruction of their subtraction) including maximum intensity projection (MIP) and then evaluated standard protocol of breast MRI. Associated findings, including axillary lymphadenopathy and invasion to nipple, skin, or pectoralis muscle were also evaluated. The concordance rate of abbreviated with standard protocol in screening and diagnostic settings were also compared, based on BI-RADS classification. Diagnostic accuracy, sensitivity, specificity, and positive and negative predictive value were calculated. A total of 108 (26.5%) of 408 patients (mean age = 43 ± 9 years) were classified as BI-RADS 4-5 and considered positive findings based on suspicious enhancement (mass or non-mass enhancement). Compared to standard protocol, abbreviated protocol revealed >98% accuracy in the diagnostic setting as well as 100% accuracy in the screening setting. Concordance rates in screening and diagnostic settings were 99.6% and 98.1%, respectively. There was no discordance between abbreviated and standard protocol in the evaluation of associated findings. Abbreviated MRI protocol possesses substantial diagnostic accuracy in both screening and diagnostic settings. Additional information provided by standard protocol might not require for cancer detection.

Contrast-enhanced mammography-guided biopsy: technical feasibility and first outcomes

ObjectivesTo evaluate the feasibility of contrast-enhanced mammography (CEM)-guided biopsy at Hospital del Mar, a Spanish university hospital.MethodsWe retrospectively reviewed all consecutive women with a suspicious enhancing finding eligible for CEM-guided biopsy, who were prospectively enrolled in a pre-marketing clinical validation and feasibility study (October 2019 to September 2021). CEM-guided biopsy is a stereotactic-based procedure that, by using intravenous iodinated contrast media administration and dual-energy acquisition, provides localisation of enhancing lesions. All the biopsies were performed using a vacuum-assisted device. We collected procedural characteristics (patient position and type of approach), and histopathological results. Feasibility endpoints included success (visualisation of the enhancing lesion, post-procedural biopsy changes and clip placement), procedural time, number of scout acquisitions and complications.ResultsA total of 66 suspicious enhancing lesions (18.0% foci, 44.0% mass, 38.0% non-mass enhancement; median size 8.5 mm) in 64 patients (median age 59 years, mostly minimal [48.4%] or mild [32.8%] background parenchymal enhancement) were referred for CEM-guided biopsy in the study period. The success rate was 63/66 (95.4%). Amongst successful procedures, patients were most frequently seated (52/63, 82.5%) and the preferred approach was horizontal (48/63, 76.2%). Median total time per procedure was 15 min. Median number of acquisitions needed before targeting was 2 (range 1–4). Complications consisted of hematoma (17/63, 27%) and vasovagal reaction (2/63, 3.2%). At histology, the malignancy rate was 25/63 (39.7%).ConclusionIn this first patient series, CEM-guided breast biopsy was feasible, with success and complication rates similar to those previously reported for magnetic resonance guidance.Key points• CEM may be used to guide biopsy of enhancing lesions through a stereotactic-based procedure combined with intravenous iodinated contrast media administration and dual-energy acquisition.• In this first patient series (n = 64), the success rate of CEM-guided biopsy was above 95%, the only complications were hematoma (22.2%) and vasovagal reaction (3.2%), and median total time per procedure was 15 min.• CEM-guided biopsy is feasible and could potentially be a widely available biopsy technique for enhancing-only lesions.

CEUS Versus MRI in Evaluation of the Effect of Microwave Ablation of Breast Cancer.

Percutaneous microwave ablation (MWA) is a new minimally invasive technique for breast cancer treatment. The aim of this research was to compare the differences in performance between contrast-enhanced ultrasound (CEUS) and magnetic resonance imaging (MRI) with respect to the curative effect of MWA in the treatment of breast cancer. Between 2015 and 2019, 26 patients with breast cancer underwent ultrasound-guided MWA. All patients underwent both CEUS and MRI within 3 d after ablation. If either of the two imaging modalities revealed suspicious enhancement of the ablation zone and the ultrasound-guided biopsy confirmed residual tumor in the suspicious area, supplementary MWA was applied. The diagnostic efficacy of CEUS and MRI within 3 d after ablation was evaluated based on a >6-mo follow-up of 26 patients. Two cases were diagnosed with residual tumors by ultrasound that were missed by MRI. Three cases were diagnosed with residual tumors by MRI that were missed by CEUS. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of CEUS in the diagnosis of complete ablation were 100%, 40%, 87.5%, 100% and 88.5%, respectively. The sensitivity, specificity, PPV, NPV and accuracy of MRI in the diagnosis of complete ablation were 100%, 60%, 91.3%, 100% and 92.3%, respectively. Within 3 d, both CEUS and MRI can efficiently assess the efficacy of MWA of breast cancer.

Steady-state ferumoxytol-enhanced MRI: early observations in benign abdominal organ masses and clinical implications

IntroductionThe off-label use of ferumoxytol as a vascular MR imaging agent is growing rapidly. However, the properties of ferumoxytol suggest that it may play an important role in the detection and characterization of abdominal mass lesions.MethodsThirty-six patients with benign abdominal mass lesions who underwent MR angiography with ferumoxytol also had T2-weighted HASTE imaging and fat-suppressed 3D T1-weighted imaging. The T1 and T2 enhancement characteristics of the lesions were analyzed and correlated with other imaging modalities and/or surgical findings and/or clinical follow-up.ResultsIn all patients with benign masses in the liver (n = 22 patients), spleen (n = 6 patients), kidneys (n = 33 patients), adrenal (n = 2 patients) and pancreas (n = 4 patients), based on the enhancement characteristics with ferumoxytol, readers were confident of the benign nature of the lesions and their conclusions were consistent with correlative imaging, tissue sampling and follow-up. One patient with a suspicious enhancing 2F Bosniak renal cyst had renal cell carcinoma confirmed on biopsy.ConclusionFerumoxytol-enhanced MRI can increase diagnostic confidence for benign abdominal masses and can increase the conspicuity of mass lesions, relative to unenhanced MRI.Graphic

Utility of Targeted Ultrasound to Predict Malignancy Among Lesions Detected on Contrast-Enhanced Digital Mammography.

BACKGROUND. Targeted ultrasound (US) can be performed to characterize and potentially biopsy areas of enhancement detected on contrast-enhanced mammography (CEM). OBJECTIVE. The purpose of this study was to assess the utility of targeted US in predicting malignancy of lesions with indeterminate or suspicious enhancement on CEM. METHODS. One thousand consecutive CEM examinations with same-day targeted breast US at one institution between October 2013 and May 2018 were retrospectively reviewed. All patients with indeterminate or suspicious enhancement detected on CEM that underwent US evaluation were included. Patients with palpable or symptomatic lesions, those with suspicious findings on low-energy mammograms or images obtained with another modality, and those with less than 1 year of follow-up were excluded. Medical records, imaging, and pathology data were reviewed. Histopathologic analysis was used as the reference standard for biopsied lesions, and follow-up imaging was used for unbiopsied lesions. Associations between pathologic diagnosis, presence of a US correlate, and lesion characteristics were assessed by Fisher exact, chi-square, and Wilcox-on rank sum tests. RESULTS. Among 153 enhancing lesions detected on CEM in 144 patients, 47 (31%) had a US correlate. The frequency of a correlate between CEM and US was significantly higher among enhancing masses (28/43 [65%]) than among lesions exhibiting nonmass enhancement (19/110 [17%]) (p < .001). The likelihood of malignancy was significantly greater among lesions with a US correlate (12/47 [26%]) than among those without a US correlate (11/106 [10%]) (p = .03), and among mass lesions (11/43 [26%]) than among nonmass lesions (12/110 [11%]) (p = .04). The PPV of US-guided biopsy after CEM-directed US was 32%. CONCLUSION. Enhancing CEM-detected lesions that have a US correlate are more likely to be malignant and can be evaluated with US-guided biopsy to obviate additional breast MRI. CLINICAL IMPACT. CEM-directed US of enhancing lesions is useful given that lesions with a US correlate are more likely to be malignant and can be used as targets for US-guided biopsy until a CEM biopsy system becomes commercially available.

An unusual cause of a toddler with a big belly, abdominal lymphatic malformation case report

: Abdominal pain is one of the most common complaints seen in the pediatric emergency department (PED). Because of the broad range of potential diagnoses, it can pose challenges in the diagnostic evaluation and treatment in the young child. A 3-year-old previously healthy girl presented to our PED with abdominal pain, abdominal distention, poor appetite, and recent weight gain. Physical examination was notable for a significantly distended taut abdomen in an otherwise well appearing child with normal vital signs. Initial evaluation yielded anemia, elevated inflammatory markers, and an abdominal ultrasound (US) showing a large amount of complex intra-abdominal ascites without definite intra-peritoneal mass. Pediatric surgery, pediatric gastroenterology, and pediatric oncology were consulted. A magnetic resonance imaging (MRI) of the abdomen was performed and revealed a large amount of intraperitoneal fluid with a component of internal complexity and no suspicious enhancement to suggest overt malignant process. She was ultimately diagnosed with a large congenital omental cyst that required resection and omentectomy. Pathology was consistent with a macrocystic lymphatic malformation. Lymphatic malformations are uncommon pediatric lesions, accounting for only 5% of benign tumors in childhood. Common locations include the neck, axillae, and rarely involve the gastrointestinal tract. Clinical presentation varies depending on the size and location of the tumor. Many present later in life due to their diagnostic challenges.

Diagnostic accuracy of breast MRI for patients with suspicious nipple discharge and negative mammography and ultrasound: a prospective study.

To evaluate the diagnostic accuracy of breast MRI in identifying lesions requiring excision for patients with suspicious nipple discharge but normal mammograms and ultrasounds. Between September 2013 and May 2019, 106 female participants (mean age 57.9 years) were consecutively included in this prospective multicenter study; 102 were retained for analysis. MRI was considered negative in the absence of suspicious enhancement and positive in cases of ipsilateral abnormal enhancement (BI-RADS 3 to 5). Final diagnoses were based on histological findings of surgical or percutaneous biopsies or at 1-year follow-up. We considered all lesions requiring excision found on pathology (papilloma, atypia, nipple adenomatosis, or cancer) as positive results. We considered spontaneous resolution of the discharge at 1 year as a negative result. MRI showed ipsilateral abnormal enhancement in 54 patients (53%) revealing 46 lesions requiring excision (31 benign papillomas, 5 papillomas with atypia, 2 nipple adenomatosis, and 8 cancers) and 8 benign lesions not requiring excision. No suspicious enhancement was found in the remaining 48 participants (47%). Forty-two were followed up at 1 year with spontaneous resolution of the discharge and six underwent surgery (revealing 2 benign papillomas). MRI diagnostic accuracy for the detection of a lesion requiring excision was as follows: sensitivity 96%, specificity 85%, positive predictive value 85%, and negative predictive value 96%. In patients with suspicious nipple discharge and normal mammogram and ultrasound, MRI demonstrates excellent performance to identify lesions for which excision is required. Normal MRI indicates it is safe to propose follow-up only management, thus avoiding unnecessary duct excision. ClinicalTrials.gov NCT02819362 KEY POINTS: • Breast MRI can be useful for the management of patients with suspicious nipple discharge and negative mammogram and ultrasound. • MRI detected a lesion requiring excision in 46 participants (45%) with unexplained discharge. • If breast MRI is negative, follow-up is a safe alternative for these patients.

Atypical ductal hyperplasia: breast DCE-MRI can be used to reduce unnecessary open surgical excision.

To evaluate the diagnostic performance of dynamic contrast-enhanced (DCE)-MRI in predicting malignancy after percutaneous biopsy diagnosis of atypical ductal hyperplasia (ADH). In this retrospective study, 68 lesions (66 women) with percutaneous biopsy diagnosis of ADH and pre-operative breast DCE-MRI performed between January 2016 and December 2017 were included. Two radiologists reviewed in consensus mammography, ultrasound, and MR images. The final diagnosis after surgical excision was used as standard of reference. Clinical and imaging features were compared in patients with and without upgrade to malignancy after surgery. The diagnostic performance of DCE-MRI in predicting malignant upgrade was evaluated. A 9-gauge vacuum-assisted biopsy was performed in 40 (58.8%) cases and a 14-gauge core needle biopsy in 28 (41.2%) cases. Upgrade to malignancy was observed in 17/68 (25%) lesions, including 4/17 (23.5%) cases of invasive cancer and 13/17 (76.5%) cases of ductal carcinoma in situ (DCIS). In 16/17 (94.1%) malignant and 20/51 (39.2%) benign lesions, a suspicious enhancement could be recognized in DCE-MRI. The malignant lesion without suspicious enhancement was a low-grade DCIS (4mm size). Sensitivity, specificity, positive predictive value, and negative predictive value of DCE-MRI on predicting malignancy were respectively 94.1%, 60.7%, 44.4%, and 96.8%. No other clinical or imaging features were significantly different in patients with and without upgrade to malignancy. After a percutaneous biopsy diagnosis of ADH, malignancy can be ruled out in most of the cases, if no suspicious enhancement is present in the biopsy area at DCE-MRI. Breast DCE-MRI may be used to avoid surgery in more than half of the patients with final benign diagnosis. • Breast DCE-MRI can safely rule out malignancy if no suspicious enhancement is present in the biopsy area after a percutaneous biopsy diagnosis of ADH. • All cases of upgrade to high-grade DCIS and invasive cancers can be identified at breast DCE-MRI after a percutaneous biopsy diagnosis of ADH. • Breast DCE-MRI may be used to avoid surgery in more than half of the patients with final benign diagnosis.

Surgical margin follow-up after nephron-sparing surgery: the possible role of CEUS

To evaluate the possible role of CEUS in the management of patients who underwent nephron-sparing surgery (NSS) and presented questionable findings on the surgical margins at the CECT follow-up exam. In our retro-prospective study, we included 952 patients with small renal masses (SRMs) treated with NSS between 2012 and 2015 and followed with CECT for at least 3years at Careggi University Hospital. Twenty-two of them presented solid masses on the site of surgery with questionable enhancement at CECT and were further studied with CEUS. This examination was followed by a quantitative analysis of the enhancement pattern. Out of the 22 masses, 18 were considered possible granulomas, presenting slow wash-in and low enhancement peaks compared to the surrounding parenchyma and persistent delayed wash-out at CEUS. Four lesions presented a suspicious malignant enhancement pattern, with rapid wash-in, high peak and rapid wash-out. In accordance with instructions from the urologist, the first group of 18 patients was strictly monitored, revealing that the mass dimensions and enhancement pattern were stable for at least 3years of follow-up, while the other 4 patients underwent a second intervention and their masses were confirmed as tumor recurrence at the histopathological evaluation. CEUS can play a key role in the surgical margin follow-up after NSS when a suspicious enhancing mass is detected by CECT, giving an accurate depiction of the enhancement pattern and thus helping the clinician in the management of the patient.

Imaging finding in diabetic mastopathy: A case report

Diabetic mastopathy is an uncommon immunologic breast disease occurring usually in patients under long-term insulin treatment. It can pose a question of differential diagnosis with breast cancer especially in case of family history of breast cancer. We report the radiological diagnostic approach of a case of diabetic mastopathy with family history of breast cancer. The mammogram was nonspecific. Ultrasound showed two suspicious masses of right breast without suspicious enhancement on MRI. Diabetic mastopathy was confirmed on histology without cancer cells. Diabetic mastopathy is a diagnostic challenge and needs to be suspected in all patients with type I diabetes. Image-guided biopsy confirmation remains mandatory. The literature is briefly reviewed.

Management of high-risk breast lesions found on mammogram or ultrasound: the value of contrast-enhanced MRI to exclude malignancy

PurposeTo evaluate the performance of magnetic resonance imaging (MRI) to exclude malignancy in biopsy-proven high-risk breast lesions prior to surgical excision. Material and methodsBreast MRIs performed after a core needle biopsy (CNB) yielding high-risk pathology were evaluated for the presence of suspicious enhancement. The diagnostic performance of MRI to exclude malignancy was calculated. ResultsThe average reader sensitivity, specificity, negative predictive value, positive predictive value and accuracy of MRI were 92%, 51%, 98%, 22% and 56%, respectively. ConclusionLack of enhancement on MRI at the site of a high-risk lesion was useful for excluding malignancy.

Mediastinal and Pleural MR Imaging: Practical Approach for Daily Practice.

Radiologists in any practice setting should be prepared to use thoracic magnetic resonance (MR) imaging for noncardiac and nonangiographic applications. This begins with understanding the sequence building blocks that can be used to design effective thoracic MR imaging protocols. In most instances, the sequences used in thoracic MR imaging are adapted from protocols used elsewhere in the body. Some modifications, including the addition of electrocardiographic gating or respiratory triggering, may be necessary for certain applications. Once protocols are in place, recognition of clinical scenarios in which thoracic MR imaging can provide value beyond other imaging modalities is essential. MR imaging is particularly beneficial in evaluating for benign features in indeterminate lesions. In lesions that are suspected to be composed of fluid, including mediastinal cysts and lesions composed of dilated lymphatics, MR imaging can confirm the presence of fluid and absence of suspicious enhancement. It can also be used to evaluate for intravoxel lipid, a finding seen in benign residual thymic tissue and thymic hyperplasia. Because of its excellent contrast resolution and potential for subtraction images, MR imaging can interrogate local treatment sites for the development of recurrent tumor on a background of post-treatment changes. In addition to characterization of lesions, thoracic MR imaging can be useful in surgical and treatment planning. By identifying nodular sites of enhancement or areas of diffusion restriction within cystic or necrotic lesions, MR imaging can be used to direct sites for biopsy. MR imaging can help evaluate for local tumor invasion with the application of "real-time" cine sequences to determine whether a lesion is adherent to an adjacent structure or surface. Finally, MR imaging is the modality of choice for imaging potential tumor thrombus. By understanding the role of MR imaging in these clinical scenarios, radiologists can increase the use of thoracic MR imaging for the benefit of improved decision making in the care of patients. ©RSNA, 2018.

Pathologic Findings of Breast Lesions Detected on Magnetic Resonance Imaging.

- Breast magnetic resonance imaging (MRI) is now used routinely for high-risk screening and in the evaluation of the extent of disease in newly diagnosed breast cancer patients. Morphologic characteristics and the kinetic pattern largely determine how suspicious a breast lesion is on MRI. Because of its high sensitivity, MRI identifies a large number of suspicious lesions. However, the low to moderate specificity and the additional cost have raised questions regarding its frequent use. - To identify the pathologic entities that frequently present as suspicious enhancing lesions and to identify specific MRI characteristics that may be predictive of malignancy. - One hundred seventy-seven MRI-guided biopsies from 152 patients were included in the study. The indication for MRI, MRI features, pathologic findings, and patient demographics were recorded. The MRI findings and the pathology slides were reviewed by a dedicated breast radiologist and breast pathologists. - Seventy-one percent (126 of 177) of MRI-guided breast biopsies were benign, 11% (20 of 177) showed epithelial atypia, and 18% (31 of 177) showed malignancy. The vast majority (84%; 62 of 74) of MRI lesions with persistent kinetics were benign. However, 57% (17 of 30) of lesions with washout kinetics and 65% (62 of 95) of mass lesions were also benign. - Magnetic resonance imaging detects malignancies undetected by other imaging modalities but also detects a wide variety of benign lesions. Benign and malignant lesions identified by MRI share similar morphologic and kinetic features, necessitating biopsy for histologic confirmation.

A new method to reduce false positive results in breast MRI by evaluation of multiple spectral regions in proton MR-spectroscopy

ObjectivesTo investigate whether the evaluation of multiple spectral regions can increase the diagnostic performance of 1H-MRS of the breast and reduce false positive findings. Methods93 patients (mean age 56 years, range 23–79) undergoing breast MRI for routine clinical indications on a 1.5T scanner were eligible for this IRB-approved prospective study. Suspicious enhancing lesions ≥8mm underwent single-voxel point-resolved 1H-MRS (PRESS, TR=2000ms, TE=272ms). Histology showed 69 malignant and 24 benign lesions. The Signal-to-Noise ratio of choline, olefinic acids and the water-to-methylene ratio were measured. The area under the ROC-curve (AUC) was used to evaluate single measurements. Combined diagnostic accuracy was explored using a 10-fold cross-validated Chi-squared automatic interaction detection (CHAID) analysis. Inter-reader agreement was evaluated in a subset of patients. ResultsA significant AUC for differentiation between benign and malignant lesions was identified for choline (0.733, P=0.001), olefinic acids (0.769, P=0.0001) and water-to-methylene ratio (0.704, P=0.003). All three variables were included in a classification algorithm using CHAID methodology. Using this classification, 70.8% (17/24) false positive diagnoses in benign lesions would have been avoided. Inter-reader agreement was almost perfect. ConclusionsThe combined evaluation of multiple spectral regions can increase the diagnostic performance of 1H-MRS and potentially reduce false positive findings.

Value of breast MRI for patients with a biopsy showing atypical ductal hyperplasia (ADH).

To evaluate the diagnostic value of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) for patients with atypical ductal hyperplasia (ADH) in predicting malignant upgrade. 3T DCE-MRI was performed for 17 patients with ADH (median age 52, range 42-76) proven by stereotactic biopsy (n = 15), and ultrasound-guided biopsy (n = 2) from January 2011 to April 2015. All patients underwent surgical excision after the MRI. Two radiologists prospectively reviewed the MRI to determine the presence or absence of suspicious findings at the site of biopsy, and evaluated the MR features of any lesion present according to the Breast Imaging Reporting and Data System (BI-RADS) lexicon. MRI findings and clinical information were correlated with the final surgical pathology by multivariate analysis. Nine of 17 lesions were upgraded to malignancy. MRI demonstrated suspicious nonmass enhancement (NME) at the site of biopsy in all upgraded patients. The median size was 19.5 mm (range, 9-44 mm). In the eight patients without upgrade, no enhancement (n = 2), linear enhancement along the biopsy track (n = 4), thin rim enhancement around hematoma (n = 1), and a focal NME (n = 1) were seen. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MRI findings were 100, 87.5, 90, and 100%, respectively. Multivariate analysis revealed that the presence of suspicious enhancement on MRI was the most significant predictor of upgrade to malignancy (P = 0.0006) CONCLUSION: Our study revealed a high NPV of DCE-MRI for patients with ADH in terms of malignant upgrade at subsequent surgery. This suggests that patients with ADH without suspicious enhancement on DCE-MRI might be followed with DCE-MRI rather than undergoing surgical excision. 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1738-1747.