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Background: Despite the nearly ubiquitous reported use of peer review among reputable medical journals, there is limited evidence to support the use of peer review to improve the quality of biomedical research and in particular, imaging diagnostic test accuracy (DTA) research. Purpose: To evaluate whether peer review of DTA studies published by imaging journals is associated with changes in completeness of reporting, transparency for risk of bias assessment, and spin. Study Type: Retrospective cross-sectional study. Study Sample: Cross-sectional study of articles published in Journal of Magnetic Resonance Imaging (JMRI), Canadian Association of Radiologists Journal (CARJ), and European Radiology (EuRad) before March 31, 2020. Assessment: Initial submitted and final versions of manuscripts were evaluated for completeness of reporting using the Standards for Reporting Diagnostic Accuracy Studies (STARD) 2015 and STARD for Abstracts guidelines, transparency of reporting for risk of bias assessment based on Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2), and actual and potential spin using modified published criteria. Statistical Tests: Two-tailed paired t-tests and paired Wilcoxon signed-rank tests were used for comparisons. A P value

The aim of this study was to evaluate a deep learning method designed to increase the contrast-to-noise ratio in contrast-enhanced gradient echo T1-weighted brain magnetic resonance imaging (MRI) acquisitions. The processed images are quantitatively evaluated in terms of lesion detection performance.A total of 250 multiparametric brain MRIs, acquired between November 2019 and March 2021 at Gustave Roussy Cancer Campus (Villejuif, France), were considered for inclusion in this retrospective monocentric study. Independent training (107 cases; age, 55 ± 14 years; 58 women) and test (79 cases; age, 59 ± 14 years; 41 women) samples were defined. Patients had glioma, brain metastasis, meningioma, or no enhancing lesion. Gradient echo and turbo spin echo with variable flip angles postcontrast T1 sequences were acquired in all cases. For the cases that formed the training sample, "low-dose" postcontrast gradient echo T1 images using 0.025 mmol/kg injections of contrast agent were also acquired. A deep neural network was trained to synthetically enhance the low-dose T1 acquisitions, taking standard-dose T1 MRI as reference. Once trained, the contrast enhancement network was used to process the test gradient echo T1 images. A read was then performed by 2 experienced neuroradiologists to evaluate the original and processed T1 MRI sequences in terms of contrast enhancement and lesion detection performance, taking the turbo spin echo sequences as reference.The processed images were superior to the original gradient echo and reference turbo spin echo T1 sequences in terms of contrast-to-noise ratio (44.5 vs 9.1 and 16.8; P0.001), lesion-to-brain ratio (1.66 vs 1.31 and 1.44; P0.001), and contrast enhancement percentage (112.4% vs 85.6% and 92.2%; P0.001) for cases with enhancing lesions. The overall image quality of processed T1 was preferred by both readers (graded 3.4/4 on average vs 2.7/4; P0.001). Finally, the proposed processing improved the average sensitivity of gradient echo T1 MRI from 88% to 96% for lesions larger than 10 mm ( P = 0.008), whereas no difference was found in terms of the false detection rate (0.02 per case in both cases; P0.99). The same effect was observed when considering all lesions larger than 5 mm: sensitivity increased from 70% to 85% ( P0.001), whereas false detection rates remained similar (0.04 vs 0.06 per case; P = 0.48). With all lesions included regardless of their size, sensitivities were 59% and 75% for original and processed T1 images, respectively ( P0.001), and the corresponding false detection rates were 0.05 and 0.14 per case, respectively ( P = 0.06).The proposed deep learning method successfully amplified the beneficial effects of contrast agent injection on gradient echo T1 image quality, contrast level, and lesion detection performance. In particular, the sensitivity of the MRI sequence was improved by up to 16%, whereas the false detection rate remained similar.

To compare the diagnostic performance of two different sets of magnetic resonance imaging (MRI) for the detection of subchondral erosions in the sacroiliac joints regarding the application of fat-water separation techniques when acquiring T1-weighted (T1w) images, using multi-detector computed tomography (MDCT) as the reference standard. We retrospectively included 31 consecutive patients having or being suspected for axial spondyloarthritis (SpA) assessed using both MRI and MDCT. Three sets of images were independently assessed for the presence of erosions by two musculoskeletal radiologists (R1, R2): (1) MRI with standard T1w without fat suppression, (2) MRI with both T1w with and without fat suppression, and (3) MDCT. The diagnostic performance of both sets of MRIs was assessed using MDCT as the referent. The assessment of T1w images with fat suppression substantially increased sensitivity (76% vs. 63% R1; 70% vs. 60% R2), specificity (97% vs. 84% R1; 96% vs. 81% R2), positive predictive value (85% vs. 45% R1; 81% vs. 40% R2), and overall accuracy (94% vs. 80% R1; 92% vs. 77% R2) in the detection of erosions when compared to the assessment using T1w images without fat suppression. The assessment of T1w images with fat suppression substantially improves the diagnostic performance of MRI in the detection of erosions in the sacroiliac joints. • The presence of erosions in the sacroiliac joints may influence the decision on the diagnosis of axial spondyloarthritis. • T1w fat-suppressed MR imaging relatively increases the contrast between the joint space (high signal) and the adjacent subchondral bone (low signal), potentially improving the detection of erosions in the sacroiliac joints. • T1w fat-suppressed images improve the diagnostic performance of MRI in the detection of erosions in the sacroiliac joints compared to T1w without fat suppression, using MDCT as the reference.

Nonalcoholic fatty liver disease (NAFLD) is a growing concern in the aging population with human immunodeficiency virus (HIV). Screening for NAFLD is recommended in patients with metabolic risk factors or unexplained transaminitis. This study aimed to prospectively assess the prevalence and associated factors of liver steatosis and advanced fibrosis (AF) in HIV-monoinfected patients at risk of NAFLD.We conducted a multicenter study in HIV-monoinfected patients, nonexcessive drinkers with metabolic syndrome, and/or persistently elevated liver enzymes, and/or clinical lipodystrophy. All participants had magnetic resonance imaging proton density fat fraction (MRI-PDFF), Fibroscan/controlled attenuation parameter (CAP), and cytokine and genetic analysis.From March 2014 to November 2015, we enrolled 442 participants and analyzed 402: male (85%); median age, 55 years (interquartile range [IQR], 50-61 years); body mass index, 27.0 kg/mIn a large cohort of HIV-moninfected patients at risk of NAFLD, steatosis is present in two-thirds of cases, and around 10% have AF. The CAP technique is accurate for screening steatosis in this population.

This study proposes and evaluates a deep learning method that predicts surrogate images for contrast-enhanced T1 from multiparametric magnetic resonance imaging (MRI) acquired using only a quarter of the standard 0.1 mmol/kg dose of gadolinium-based contrast agent. In particular, the predicted images are quantitatively evaluated in terms of lesion detection performance. Materials and methods This monocentric retrospective study leveraged 200 multiparametric brain MRIs acquired between November 2019 and February 2020 at Gustave Roussy Cancer Campus (Villejuif, France). A total of 145 patients were included: 107 formed the training sample (55 ± 14 years, 58 women) and 38 the separate test sample (62 ± 12 years, 22 women). Patients had glioma, brain metastases, meningioma, or no enhancing lesion. T1, T2-FLAIR, diffusion-weighted imaging, low-dose, and standard-dose postcontrast T1 sequences were acquired. A deep network was trained to process the precontrast and low-dose sequences to predict "virtual" surrogate images for contrast-enhanced T1. Once trained, the deep learning method was evaluated on the test sample. The discrepancies between the predicted virtual images and the standard-dose MRIs were qualitatively and quantitatively evaluated using both automated voxel-wise metrics and a reader study, where 2 radiologists graded image qualities and marked all visible enhancing lesions. Results The automated analysis of the test brain MRIs computed a structural similarity index of 87.1% ± 4.8% between the predicted virtual sequences and the reference contrast-enhanced T1 MRIs, a peak signal-to-noise ratio of 31.6 ± 2.0 dB, and an area under the curve of 96.4% ± 3.1%. At Youden's operating point, the voxel-wise sensitivity (SE) and specificity were 96.4% and 94.8%, respectively. The reader study found that virtual images were preferred to standard-dose MRI in terms of image quality (P = 0.008). A total of 91 reference lesions were identified in the 38 test T1 sequences enhanced with full dose of contrast agent. On average across readers, the brain lesion SE of the virtual images was 83% for lesions larger than 10 mm (n = 42), and the associated false detection rate was 0.08 lesion/patient. The corresponding positive predictive value of detected lesions was 92%, and the F1 score was 88%. Lesion detection performance, however, dropped when smaller lesions were included: average SE was 67% for lesions larger than 5 mm (n = 74), and 56% with all lesions included regardless of their size. The false detection rate remained below 0.50 lesion/patient in all cases, and the positive predictive value remained above 73%. The composite F1 score was 63% at worst. Conclusions The proposed deep learning method for virtual contrast-enhanced T1 brain MRI prediction showed very high quantitative performance when evaluated with standard voxel-wise metrics. The reader study demonstrated that, for lesions larger than 10 mm, good detection performance could be maintained despite a 4-fold division in contrast agent usage, unveiling a promising avenue for reducing the gadolinium exposure of returning patients. Small lesions proved, however, difficult to handle for the deep network, showing that full-dose injections remain essential for accurate first-line diagnosis in neuro-oncology.

In their article, Fucà et al highlight that early tumor shrinkage and depth of response predict the prognosis of patients with metastatic colorectal cancer (mCRC) microsatellite instability (MSI-H)/deficient mismatch repair (dMMR) treated by immune checkpoint inhibitors (ICI). We are surprised that no cases of pseudoprogression (PSPD) were reported in their study. PSPDs were described under ICI in patients treated for MSI/dMMR mCRC. In a cohort of 123 patients treated with anti-PD1±antiCTL-4 for MSI/dMMR mCRC, we reported 12 patients with PSPD, representing 10% of the cohort. Of 12 patients with PSPD, 8 secondary achieved an objective response and were alive and free of progression at the data lock. Conversely, in Fucà’s article, no PSDP was observed and the patients with primary radiological progression (21.7%) had a poor overall survival. These differences between the two series could be probably explained by the following points. First, Fucà et al use RECIST 1.1 criteria for radiological evaluation. Second, the first imaging was done after 8–9 weeks of treatment in Fucà’s article, which may be late to detect PSPD. In conclusion, if the first evaluation is made during the first 3 months of treatment, using iRECIST criteria seems mandatory to avoid stopping treatment prematurely, especially in patients receiving anti-PD1 alone.

Background The AcSé-crizotinib program provides extensive screening of crizotinib-targeted genomic alteration in several malignancies. We here report the results in patients with esogastric MET-amplified adenocarcinomas. Objective The objective of the study was to evaluate the efficacy and tolerability of crizotinib in patients with pretreated esogastric MET-amplified adenocarcinoma who have no alternative treatment options. Patients and Methods MET expression was evaluated by fluorescence in situ hybridization in tumor samples with immunohistochemistry scores ≥ 2+. Patients with chemo-refractory tumors showing ≥ 6 MET copies were eligible for crizotinib 250 mg twice daily. The primary efficacy outcome was the objective response rate after two cycles of crizotinib. Results MET was prospectively analyzed in 570 esogastric adenocarcinomas. Amplifications were found in 35/570 adenocarcinomas (29/523 gastric and 6/47 esophageal). Nine patients were treated with crizotinib. The objective response rate after two cycles was 33.3% (95% CI 7.5–70), the best overall response rate was 55.6% (95% CI 21.2–86.3), with median progression-free survival of 3.2 months (95% CI 1.0–5.4), and overall survival of 8.1 months (95% CI 1.7–24.6). Safety was consistent with that previously reported for crizotinib. Conclusions Large-scale screening for MET-amplified esogastric adenocarcinomas is feasible. MET amplification was observed in 5.5% of gastric and 12.8% of esophageal adenocarcinomas. Crizotinib shows encouraging results in selected patients. Thus, c-MET inhibition for MET-amplified tumors deserves further evaluation. Trial Registration Number NCT02034981. Date of Registration 14 January 2014.

Background The efficacy of immune checkpoint inhibitors (ICIs) in microsatellite instability-high/DNA mismatch repair (MSI/dMMR) metastatic colorectal cancer (mCRC) is well established. ICIs are responsible for pseudoprogression (PSPD) that complicates clinical decisions. We evaluated the PSPD frequency in patients with MSI/dMMR mCRC treated with ICIs. Patients and methods Consecutive patients with MSI/dMMR mCRC treated with ICIs from February 2015 to December 2019 at Saint-Antoine Hospital were included. Imaging was retrospectively and centrally reviewed according to Response Evaluation Criteria in Solid Tumours, version 1.1 (RECIST 1.1) and immune RECIST (iRECIST). PSPD was defined as an unconfirmed disease progression by iRECIST. Results One hundred twenty-three patients with MSI/dMMR mCRC were included. Thirty-six patients (29%) had radiological PD according to RECIST 1.1 during the median follow-up of 22.3 months (95% confidence interval [CI], 1.5–62.2), including 22 in the first 3 months (the primary radiological PD). Twenty-nine patients continued ICIs beyond PD. Twelve patients experienced PSPD, representing 10% of the population and 52% of the primary radiological PD. The median time to PSPD was 5.7 weeks (95% CI, 4.1–11.4). No PSPD was observed after 3 months. The PSPD incidence was 14.8% in patients treated with anti-PD1 alone (n = 9/61) and 4.8% in case of anti-PD1 plus anti-CTLA-4 (n = 3/62). Eight patients with PSPD experienced an objective response. The 2-year progression-free survival and overall survival rates for patients with PSPD were 70.0% (95% CI, 32.9–89.2) and 75.0% (95% CI, 29.8–93.4), respectively. Conclusion Patients with MSI/dMMR mCRC treated with ICIs experienced PSPDs. PSPD occurred within the first 3 months and represented most of the primary radiological PDs. The use of iRECIST criteria should be questioned after 3 months.

Abstract This review explains in simple terms, accessible to the non-statistician, general principles regarding the correct research methods to develop and then evaluate imaging biomarkers in a clinical setting, including radiomic biomarkers. The distinction between diagnostic and prognostic biomarkers is made and emphasis placed on the need to assess clinical utility within the context of a multivariable model. Such models should not be restricted to imaging biomarkers and must include relevant disease and patient characteristics likely to be clinically useful. Biomarker utility is based on whether its addition to the basic clinical model improves diagnosis or prediction. Approaches to both model development and evaluation are explained and the need for adequate amounts of representative data stressed so as to avoid underpowering and overfitting. Advice is provided regarding how to report the research correctly. Key Points • Imaging biomarker research is common but methodological errors are encountered frequently that may mean the research is not clinically useful. • The clinical utility of imaging biomarkers is best assessed by their additive effect on multivariable models based on clinical factors known to be important. • The data used to develop such models should be sufficient for the number of variables investigated and the model should be evaluated, preferably using data unrelated to development.

To compare the diagnostic performance of two different sets of magnetic resonance imaging (MRI) for the detection of subchondral erosions in the sacroiliac joints regarding the application of fat-water separation techniques when acquiring T1-weighted (T1w) images, using multi-detector computed tomography (MDCT) as the reference standard.We retrospectively included 31 consecutive patients having or being suspected for axial spondyloarthritis (SpA) assessed using both MRI and MDCT. Three sets of images were independently assessed for the presence of erosions by two musculoskeletal radiologists (R1, R2): (1) MRI with standard T1w without fat suppression, (2) MRI with both T1w with and without fat suppression, and (3) MDCT. The diagnostic performance of both sets of MRIs was assessed using MDCT as the referent.The assessment of T1w images with fat suppression substantially increased sensitivity (76% vs. 63% R1; 70% vs. 60% R2), specificity (97% vs. 84% R1; 96% vs. 81% R2), positive predictive value (85% vs. 45% R1; 81% vs. 40% R2), and overall accuracy (94% vs. 80% R1; 92% vs. 77% R2) in the detection of erosions when compared to the assessment using T1w images without fat suppression.The assessment of T1w images with fat suppression substantially improves the diagnostic performance of MRI in the detection of erosions in the sacroiliac joints.• The presence of erosions in the sacroiliac joints may influence the decision on the diagnosis of axial spondyloarthritis. • T1w fat-suppressed MR imaging relatively increases the contrast between the joint space (high signal) and the adjacent subchondral bone (low signal), potentially improving the detection of erosions in the sacroiliac joints. • T1w fat-suppressed images improve the diagnostic performance of MRI in the detection of erosions in the sacroiliac joints compared to T1w without fat suppression, using MDCT as the reference.

BackgroundImmune checkpoint inhibitors (ICIs) are highly effective in patients with microsatellite instability/mismatch repair-deficient (MSI/dMMR) metastatic colorectal cancer (mCRC). Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria may underestimate response to ICIs due to the pseudoprogression phenomenon. The GERCOR NIPICOL phase II study aimed to evaluate the frequency of pseudoprogressions in patients with MSI/dMMR mCRC treated with nivolumab and ipilimumab.MethodsPatients with MSI/dMMR mCRC previously treated with fluoropyrimidines, oxaliplatin, and irinotecan with/without targeted therapies received nivolumab 3 mg/kg plus ipilimumab 1 mg/kg every 3 weeks for four cycles then nivolumab 3 mg/kg every 2 weeks until progression or a maximum of 20 cycles. Computed tomography scan tumor assessments were done every 6 weeks for 24 weeks and then every 12 weeks. The primary endpoint was disease control rate at 12 weeks according to RECIST 1.1 and iRECIST by central review.ResultsOf 57 patients included between December 2017 and November 2018, 48.0% received ≥3 prior lines of chemotherapy, 18.0% had BRAFV600E mutation, and 56.0% had Lynch syndrome-related cancer. Seven patients (12.0%) discontinued treatment due to adverse events; one died due to a treatment-related adverse event. The disease control rate (DCR) at 12 weeks was 86.0% with RECIST 1.1% and 87.7% with iRECIST. Two pseudoprogressions (3.5%) were observed, at week 6 and at week 36, representing 18% of patients with disease progression per RECIST 1.1 criteria. With a median follow-up of 18.4 months, median progression-free survival (PFS) and overall survival (OS) were not reached. The 12-month PFS rate was 72.9% with RECIST 1.1% and 76.5% with iRECIST. The 12-month OS rate was 84%. Overall response rate was 59.7% with both criteria. RAS/BRAF status, sidedness, Lynch syndrome, and other baseline parameters were not associated with PFS.ConclusionPseudoprogression is rare in patients with MSI/dMMR mCRC treated with nivolumab and ipilimumab. This combined ICI therapy confirms impressive DCR and survival outcomes in these patients.Trial registration numberNCT03350126.

13 Background: Optimal treatment duration with immune checkpoint inhibitors (ICI) for MSI/dMMR mCRC pts remains to be determined. Different durations are used, usually a fixed duration of 2 years or treatment until progression or toxicity. The GERCOR NIPICOL phase II study evaluated 1 year of therapy with nivolumab plus ipilimumab for MSI/dMMR mCRC pts. Here, we present the efficacy data with 16 months of additional follow-up since the primary analysis. Methods: MSI/dMMR mCRC pts previously treated with fluoropyrimidine, oxaliplatin, and irinotecan ± targeted therapies received nivolumab 3 mg/kg plus ipilimumab 1 mg/kg Q3W for 4 cycles, then nivolumab 3 mg/kg Q2W until progression or a maximum of 20 cycles. Second course of nivolumab was permitted for pts who completed the predefined year of treatment and had later progressive disease (PD). Objectives were to evaluate response rates, progression-free survival (PFS) per iRECIST, and overall survival (OS). A landmark analysis was performed for PFS in pts who remained alive and progression-free at 1 year (theoretical end of treatment). Results: Of 57 pts included between Dec 2017 and Nov 2018, 36 (63%) completed the predefined 1-year duration of treatment. Reasons of premature treatment discontinuation were PD or death (n = 13), adverse event (n = 7), and the pt wish (n = 1). Overall median follow-up was 34.5 months. One, 2, and 3-year PFS rates were respectively 75.4% (95% CI 62.0-84.6), 70.0% (95% CI 56.2-80.1), and 70.0% (95% CI 56.2-80.1). One, 2, and 3-year OS rates were 84.1 (95% CI 71.7-91.4), 78.4% (95% CI 65.1-87.1), and 73.1% (95% CI 58.4-83.4), respectively. 42/57 pts were progression-free and alive at 1 year. Among them, median follow-up was 35.0 months and the 24-month PFS rate was 92.9% (95% CI 79.5-97.6%). PD was observed in three pts whose 12-month status was stable disease (SD). These three pts received a second course of nivolumab: two achieved PR and one had PD. Conclusions: Nivolumab plus ipilimumab with a fixed duration of 1 year continued to show durable activity in pts with chemoresistant MSI/dMMR mCRC after 3 years of follow-up. Reexposure to nivolumab seems to provide additional antitumor activity for pts experiencing late resistance after discontinuation of immunotherapy. Clinical trial information: NCT033501260.

This Editorial Comment refers to the article by Bernard C. et al, Gender gap in articles published in European Radiology and CardioVascular and Interventional Radiology: evolution between 2002 and 2016, European Radiology, doi: 10.1007/s00330-019-06390-7.

Our primary aim was to evaluate the distribution and severity of cartilage damage in a sample of patients with scaphoid nonunion advanced collapse (SNAC), assessed on MDCT arthrography, with regard to two well-known SNAC staging systems. Secondarily, we wanted to see if the degree of cartilage damage varied with the location of the nonunion. We retrospectively included 35 patients with a history of SNAC who had undergone MDCT arthrography. The location of the fracture was defined as the proximal, middle, or distal third of the scaphoid. Cartilage damage was assessed in 14 distinct regions of the wrist using a modified Whole-Organ Magnetic Resonance Imaging Score (WORMS) system. Staging of SNAC for each patient was based on the distribution of cartilage damage seen on MDCT arthrography. The one-way ANOVA test was used to evaluate whether global cartilage damage scores differed between patients with proximal vs middle and distal nonunion. The radial styloid-scaphoid (85.7%), the scaphoid-trapezium-trapezoid (60%), the scapho-capitate (57.1%), and the proximal radio-scaphoid joints (42.9%) were most commonly affected by degenerative cartilage damage. A substantial number of patients could not be classified according to the two SNAC staging systems. Patients with proximal nonunion exhibited a higher mean score of global cartilage damage than patients with middle or distal nonunion: 14.3 ± 9.5 (95% CI 9.8, 18.7) vs 8.6 ± 6.9 (95% CI 4.7, 12.4); p

Purpose To evaluate the distribution and severity of cartilage damage and scapholunate dissociation assessed on multi-detector computer tomography (MDCT) arthrography in a sample of patients with scapholunate interosseous ligament (SLIL) injury, in regard to component-specific tears. Methods We retrospectively included 37 patients with SLIL tears and 34 patients without SLIL tears who served as controls, all patients had undergone MDCT arthrography. Morphology of SLIL dorsal and volar components was graded as: normal, partial, or complete tear. Cartilage damage was assessed in 14 distinct regions of the wrist using a semiquantitative modified scoring system. Staging of scapholunate advanced collapse (SLAC) for each patient was based on the distribution of cartilage damage seen on MDCT arthrography. Scapholunate dissociation was measured for each patient at the tenth of a millimeter. The Student's t-test (p) and the Wilcoxon Rank-Sum test (P) were used to compare the different groups. Results The cartilage damage scores obtained were greater in patients with complete SLIL dorsal component tear than in other patients (p = 0.0019 and P = 0.0018). Scapholunate dissociation was greater in these patients (p = 0.0003 and P = 0.0013). Scapholunate dissociation was also greater in patients with SLAC wrist (p = 0.0004 and P = 0.0012), with a cut-off value of 3.7 mm for diagnosing SLAC (sensitivity 83.3 % and specificity 89.5 %). Conclusion MDCT arthrography assessment shows that the severity of cartilage damage and scapholunate dissociation is greater when the dorsal component of the SLIL is completely ruptured.

International audience; Anne Bertrand passed away on March 2nd 2018. She was in a touring-skiers group led by a guide and swept by an avalanche in the French Alps. This paper is a tribute to Anne and an attempt, by some of her closest colleagues, to provide an overview of her major contributions. Anne Bertrand was a rising star of the neuroimaging community who traced innovative paths at the interface of basic science and clinical neuroradiology. From the very beginning of her career, she had been interested in the cross-fertilization between research and medical practice. After an MD and a specialization in neuroradiology, she prepared a PhD in preclinical imaging at the French Atomic Energy Commission (CEA) and at New York University. She was then appointed as Senior Neuroradiologist (at the Pitié-Salpêtrière and then Saint-Antoine Hospital in Paris) and Associate Professor (Sorbonne University). Simultaneously, she continued to develop her research activities in the ARAMIS Laboratory at the Brain and Spinal Cord Institute (ICM). Her main field of interest was neuroimaging of dementias. In a short time, she made important and exceptionally diverse contributions to the understanding, detection, diagnosis and tracking of these disorders (including Alzheimer's disease and fronto-temporal lobar degeneration) using advanced multimodal neuroimaging techniques. They will be a source of inspiration for all of us. Anne was not only an outstandingly bright scientist but also enlightening by her personal qualities: joy, openness, kindness and generosity.

3580 Background: Immune checkpoint inhibitors (ICI) have demonstrated efficacy in patients (pts) with MSI/dMMR mCRC. We aimed to evaluate clinical, pathological and molecular factors associated with progression-free survival (PFS) and overall survival (OS) in ICI-treated pretreated mCRC patients (pts). Methods: Pts are drawn from a prospective cohort of all patients treated with ICI for MSI/dMMR mCRC at Saint-Antoine Hospital, Paris, France. All MSI/dMMR mCRC pts with disease progression after ≥ 1 prior systemic treatment (fluoropyrimidine and oxaliplatin or irinotecan ± targeted therapy) were included. MSI/dMMR status was centrally reviewed. Lynch syndrome or sporadic status was determined according to MMR gene germline mutational testing, MLH1 methylation status and BRAFV600E mutation. PFS and objective response rate (ORR) were assessed using iRECIST criteria. The impact of Lynch syndrome on PFS was analyzed apart from the multivariate analysis due to the interaction with the BRAFV600E mutation status. Results: Of 130 included pts, 66 received anti-PD1 alone, 1 anti-PDL1 alone and 63 anti-PD1 plus anti-CTLA4. 71% have had at least 2 prior lines of treatment. 33 patients (25%) have BRAFV600Emutation (mt) and 49 (38%) RASmt. The ORR for the whole population was 62.8 % IC95% [53.8; 71.1]. Median follow-up was 21.0 months, median PFS and OS were not reached. Results of PFS unadjusted and adjusted analysis are displayed in the table. BRAFV600E and RAS mutation were not associated with PFS and OS in multivariate analyses. After adjustment for the treatment type, Hazard Ratio (HR) for PFS between patients with proven Lynch syndrome (N=44) and patients with proven sporadic tumors (n= 44) was 0.57 (95%IC 0.26 -1.26). Conclusions: In this cohort, main known clinical, pathological and molecular factors do not influence the efficacy of ICI in pre-treated MSI/dMMR mCRC.[Table: see text]

To assess liver steatosis, the controlled attenuation parameter (CAP; giving an estimate of ultrasound attenuation ∼3.5 MHz) is available with the M probe of the FibroScan. We report on the adaptation of the CAP for the FibroScan XL probe (center frequency 2.5 MHz) without modifying the range of values (100-400 dB/m). CAP validation was successfully performed on Field II simulations and on tissue-mimicking phantoms. In vivo performance was assessed in a cohort of 59 patients spanning the range of steatosis. In vivo reproducibility was good and similar with both probes. The area under receiver operative characteristic curve was equal to 0.83/0.84 and 0.92/0.91 for the M/XL probes to detect >2% and >16% liver fat, respectively, as assessed by magnetic resonance imaging. Patients can now be assessed simultaneously for steatosis and fibrosis using the FibroScan, regardless of their morphology.

101 Background: Immune checkpoint inhibitors (ICKi) are highly effective for MSI/dMMR mCRC pts. RECIST1.1 criteria are reported to underestimate response to ICKi. The GERCOR NIPICOL phase II study aimed to evaluate disease control rate (DCR) using RECIST1.1 and iRECIST for MSI/dMMR mCRC pts treated with nivolumab (NIVO) and ipilimumab (IPI). Methods: MSI/dMMR mCRC pts previously treated with fluoropyrimidines (FP), oxaliplatin (OX) and irinotecan (IRI) ± targeted therapies received NIVO 3 mg/kg + IPI 1 mg/kg Q3W for 4 cycles then NIVO 3 mg/kg Q2W until progression or a maximum of 20 cycles. CT-scan tumor assessments were done every 6 weeks during 24 weeks and then every 12 weeks. Primary objective was DCR at 12 weeks (12wDCR) according to RECIST1.1 and iRECIST by central review. Response rates and progression-free survival (PFS) by central review were secondary objectives. A one-stage Fleming design was used with a targeted improvement of 12wDCR from 70% to 85%. Results: Of 57 pts included between Dec 2017 and Nov 2018, 43.9% had received ≥ 3 prior lines including FP (100%), OX (100%), IRI (95.5%), antiangiogenics (57.9%) and anti-EGFRs (45.6%). 17.5% of pts had BRAF mutation and 27.5% Lynch syndrome. Grade 3-4 treatment-related adverse events were reported in 49.1% of pts, mainly hepatitis (12.3%). 12wDCR was 86.0% and 87.7% using RECIST1.1 and iRECIST respectively, with only 1 pseudo-progression (1.8%) observed during the first 12 weeks, and one later. Kappa coefficient between RECIST and iRECIST 12wDCR was 0.92 (95%CI 0.77-1.0). Best observed responses with RECIST1.1/iRECIST were: 2/2 complete responses (3.5/3.5%), 19/19 partial responses (33.3/33.3%), 30/31 stable diseases (52.6/54.4%) and 3/2 disease progressions (5.3/3.5%), with 3 pts not evaluable (cancer-related deaths before first evaluation). Conclusions: Combination of NIVO and IPI in MSI/dMMR mCRC is associated with a low frequency of pseudo-progression and high DCR rate. PFS will be evaluated in Dec 2019, with all pts having completed the predefined 1-year of ICKi therapy. Clinical trial information: NCT033501260.

A very large range of disorders, from benign, self-limited conditions, to processes requiring emergency surgery, can present with acute abdominal and pelvic pain. The radiologist plays a substantial role in the routine diagnosis and management of patients with these disorders. Similarly, the radiologist plays a major role in the routine evaluation of patients with abdominal and pelvic trauma, whether blunt or penetrating. Computed tomography (CT) remains the mainstay of the evaluation of such patients, although protocols have evolved along with technological advancements. Ultrasound (US) has a continued important role, particularly for evaluation of right upper quadrant pain, for evaluation of suspected gynecologic disorders, and for evaluation of pediatric and pregnant patients with an acute abdomen. Magnetic resonance imaging (MRI) has a growing role for initial evaluation as well as follow-up of selected patients with a variety of acute abdominal and pelvic conditions (usually non-traumatic). Although it is not possible to cover every aspect of imaging of acute non-traumatic and traumatic conditions of the abdomen and pelvis in a single chapter, an overview is presented, with key concepts and teaching points.

Background Different imaging techniques have been used for the investigation of the lymphatic channels and lymph glands. Noncontrast magnetic resonance (MR) lymphography has significant advantages in comparison with other imaging modalities. Methods Noncontrast MR lymphography uses very heavily T2-weighted fast spin echo sequences which obtain a nearly complete signal loss in tissue background and specific display of lymphatic vessels with a long T2 relaxation time. The raw data can be processed with different algorithms such as maximum intensity projection algorithm to obtain an anatomic representation. Results Standard T2-weighted MR images easily demonstrate the location of edema. It appears as subcutaneous infiltration of soft tissue with a classical honeycomb pattern. True collection around the muscular area may be demonstrated in case of severe lymphedema. Lymph nodes may be normal in size, number, and signal intensity; in other cases, lymph nodes may be smaller in size or number of lymph nodes may be restricted. MR lymphography allows a classification of lymphedema in aplasia (no collecting vessels demonstrated); hypoplasia (a small number of lymphatic vessels), and numerical hyperplasia or hyperplasia (with an increased number of lymphatic vessels of greater and abnormal diameter). Conclusion Noncontrast MR lymphography is a unique noninvasive imaging modality for the diagnosis of lymphedema. It can be used for positive diagnosis, differential diagnosis, and specific evaluation of lymphedema severity. It may also be used for follow-up evaluation after treatment.

The purpose of the present study was to analyse the performance of non-contrast MR lymphography for the classification of primary lower limb lymphoedema in 121 consecutive patients with 187 primary lower limb lymphoedemas. 121 consecutive patients with clinically diagnosed primary lower limb lymphoedema underwent non-contrast MR lymphography with a free-breathing 3D fast spin-echo sequence with a very long TR/TE (4000/884 ms). MR examinations were retrospectively reviewed for severity of lymphoedema (absent, mild, moderate, severe) and characteristics of inguinal lymph nodes and iliac and inguinal lymphatic trunks graded as aplasic (no lymph nodes or lymphatic trunks), hypoplasic (less lymph nodes or lymphatic trunks), normal and hyperplasic (more lymph nodes or more and/or dilated trunks). There was an excellent correlation between clinical stage and severity of lymphoedema (Cramer’s V of 0,73 (p

Resume Objectif L’objectif etait d’evaluer la qualite des comptes rendus radiologiques des examens tomodensitometriques realises pour bilan d’evaluation oncologique avant et apres intervention correctrice. Materiels et methodes Notre objectif etait d’evaluer la presence de differents items au sein des comptes rendus radiologiques realises pour evaluation tumorale de facon formelle c’est-a-dire sans verifier l’exactitude des items releves. Dix items simples ont ete evalues avant et apres une intervention correctrice correspondant a une information orale puis ecrite relative a la technique d’evaluation tumorale en tomodensitometrie. Resultats Les resultats etaient variables en fonction des items mesures. La plupart des criteres ont ete ameliores apres intervention correctrice. Mais pour certains items le resultat restait mediocre voire tres mediocre comme le choix adequat de l’examen de comparaison (baseline ou nadir). Conclusion En l’absence d’utilisation de compte rendu type, l’evaluation de la qualite des comptes rendus radiologiques des examens tomodensitometriques pour evaluation tumorale montre que la qualite des comptes rendus radiologiques reste largement sous optimale meme apres intervention correctrice.

Objective Our objective was to demonstrate the characteristic features of retroperitoneal lymphatic aneurysmal dilatation with three-dimensional (3D) magnetic resonance (MR) lymphography. Conclusion Three-dimensional MR lymphography demonstrates that retroperitoneal lymphatic aneurysmal dilatation exhibits a continuous spectrum of change from normal variants to lymphatic aneurysmal dilatation and so-called cystic lymphangioma. Main Message Non-contrast MR lymphography with very heavily T2-weighted fast spin echo sequences is a useful non-invasive technique without the need of contrast medium injection to obtain a unique evaluation of the lymphatic system To prove the lymphatic origin of a cystic formation, it is essential to demonstrate the communication with retroperitoneal lymphatic vessels 3D MR lymphography demonstrates that retroperitoneal lymphatic aneurysmal dilatation exhibits a continuous spectrum of change from normal variants to lymphatic aneurysmal dilatation and so-called cystic lymphangioma

Background ABCB4/MDR3 gene variants are mostly associated with a peculiar form of cholelithiasis in European adults, currently referred to as low phospholipid-associated cholelithiasis (LPAC) syndrome. Methods LPAC syndrome is a rare genetic disorder, characterised by the following clinical features: biliary symptoms before the age of 40, recurrence of the symptoms after cholecystectomy, and intrahepatic microlithiasis or intrahepatic hyperechogenic foci. Results Imaging features associated with ABCB4/MDR3 mutations are not specific and correspond to a wide spectrum of biliary abnormalities. The main feature is the presence of intrahepatic lithiasis. Other uncommon presentations have been described, such as uni- or multifocal spindle-shaped dilatations of the intrahepatic bile ducts filled with gallstones, secondary sclerosing cholangitis, biliary cirrhosis, and intrahepatic cholangiocarcinoma. Conclusion This review focuses on MR features related to ABCB4/MDR3 mutations. Main Messages • LPAC syndrome is characterised by intrahepatic microlithiasis or intrahepatic hyperechogenic foci. • Ultrasound examination is very accurate in detecting intrahepatic stones. • At MR imaging, LPAC syndrome is associated with various presentations.

International audience; We read with great interest the article by Ronot and colleagues in the recent issue of European Radiology about the transient mosaic pattern observed on computed tomography (CT) and magnetic resonance (MR) imaging in acute extrahepatic infection or inflammatory disease [1]. They demonstrated nicely that acute diseases of extrahepatic organs are associated with a reversible hepatic sinusoidal dilatation resulting in a mosaic enhancement pattern on contrast-enhanced CT or MR imaging. However, we were surprised that other hepatic imaging features such as periportal halo or gallbladder wall thickening were not mentioned. Basically, it is difficult to estimate the frequency of such hepatic abnormalities in patients with acute extrahepatic infections.

MRCP is a non-invasive cholangiographic technique used in detection and characterization of bile ducts abnormalities. MRCP features of primary sclerosing cholangitis are randomly distributed annular strictures alternating with slightly dilated bile ducts. Secondary sclerosing processes including ascending, ischemic, caustic, AIDS-related, eosinophilic and autoimmune cholangitis can mimic PSC at MRCP.

The purpose of our study is to use MDCT and MR imaging to describe the normal ileal pouch and to identify features of Crohn’s disease (CD) relapse in patients after ileal pouch-anal anastomosis (IPAA). After total colectomy followed by IPAA, features, optimally evaluated with pelvic MRI, such as fistulas, abscesses, pouch inflammation, and stenoses, indicate CD relapse. Although uncommon, radiologists should be aware that these imaging features strongly favor this diagnosis.

To determine the total Apparent Diffusion Coefficient (ADC), the pure Diffusion coefficient (D) and the perfusion fraction (f) in advanced hepatocellular carcinoma (HCC) under sorafenib treatment. Two target tumors were prospectively analyzed in 12 patients at baseline, 2-weeks and 2-months treatment using b values of 0, 200, 400, 800 s/mm. Repeatability error was estimated on a healthy volunteer. Lesion sizes, ADC and D values did not significantly change during treatment (overall mean values, respectively, 47.8 ± 31.0 mm, 1.34 ± 0.14 × 10−3 mm2/s and 1.18 ± 0.22 × 10−3 mm2/s). However, f values significantly increased in seven responder patients (+38.39% at 2-weeks, +50.94% at 2-months, P = 0.005) while they decreased in five non responder patients (−41.93% at 2-weeks, P = 0.006). Furthermore, f was inversely correlated with αFP levels (P = 0.032) and responder patients had a higher mean overall survival (OS) than non responder patients (12.29 ± 4.46 vs. 7.80 ± 4.97 months). The % variation of f relative to baseline at 2-months was correlated with OS (P = 0.038) and symptomatic time to progression (P = 0.022). Contrary to ADC and D, the perfusion fraction f is a valuable marker of sorafenib treatment in advanced HCC.

4054Background: Crizotinib (czb) is only registered for treating ALK and ROS1-translocated lung cancer. However, Czb is also a MET inhibitor. Several malignancies are characterized by MET amplifica...

Diffusion-weighted MR imaging of liver pathology: principles and clinical applications Due to ongoing technological advances, the range of clinical applications for diffusion-weighted MR imaging has expanded to now include abdominal pathology. Current applications for liver pathology include two main directions. First, oncologic imaging with detection, characterization and follow-up of lesions. Second, evaluation of diffuse liver diseases, including hepatic fibrosis. The diagnostic impact and role of diffusion-weighted MR imaging remain under investigation, but appear promising. Because of its short acquisition time, sensitivity, and additional information it provides, diffusion-weighted MR imaging should be included in routine liver imaging protocols.

International audience; Magnetic resonance cholangiography (MRC) has become the standard of reference for imaging of the biliary ducts. The use of three-dimensional (3D) sequences has resulted in improved spatial resolution with virtually isotropic voxel and improved signal/noise ratio. In addition to MRC images, 3D fat suppressed T1-weighted MR images should be systematically obtained to search for intrahepatic calculi. MRC plays a major role in the diagnosis of cholangiocarcinoma and assessment of its resectability. With modern MR systems the performance of MR is basically the same that of CT for evaluation of arterial and portal vein extent. MRC is a key imaging modality for the diagnosis of primary sclerosing cholangitis. Different imaging patterns may be observed including multifocal intra- and extrahepatic strictures alternating with slightly dilated ducts. Focal signal abnormality of the liver parenchyma and focal parenchymal atrophy represent the consequences of biliary duct obstruction on liver parenchyma. Diagnosis of biliary lithiasis is performed by combination of MRC and T1-weighted MR imaging. MRC can be performed for the diagnosis of secondary cholangitis including ascending cholangitis, ischemic cholangitis and IgG4-related sclerosing cholangitis. Hepatobiliary contrast agents could be used for demonstrating the site of biliary duct leakage after surgery and for functional imaging. MR imaging can also be used to determine the prognosis of PSC. The inherent limitations of MRC of bile ducts are still the suboptimal spatial resolution for evaluation of distal intrahepatic biliary ducts.

Resume Les micronodules sont frequemment rencontres en pathologie thoracique et plus souvent detectes depuis l’avenement des scanners multi-detecteurs, des possibilites de reconstructions tridimensionnelles et de l’utilisation des techniques MIP. On classe les micronodules en trois groupes, en fonction de leur topographie au sein du lobule pulmonaire secondaire : centro-lobulaires (bronchiolaires), peri-lymphatiques et de distribution hematogene (dite « au hasard »). Chaque groupe correspond a des pathologies bien particulieres. La comprehension de leur classification topographique permet, avec la confrontation aux donnees cliniques, d’orienter au mieux le diagnostic etiologique.

Resume Les auteurs rapportent un cas de carcinome renal chromophobe sous la forme d’une correlation anatomo-pathologique. Le carcinome chromophobe est le troisieme carcinome renal (5 %) apres le carcinome a cellules claires et le carcinome tubulo-papillaire. La lesion illustree ici presente un aspect polylobe, compose de masses confluentes dont certaines ont un caractere stellaire ou en rayon de roue.

Resume Correlation radiologique et pathologique chez un homme porteur d’une echinococcose alveolaire hepatique. Le diagnostic est evoque en imagerie devant une masse infiltrante, multikystique souvent responsable d’une dilatation des voies biliaires. La mise en evidence du parasite au decours permet d’affirmer le diagnostic.

PURPOSE To evaluate the feasibility, efficacy, and tolerance of self-expanding metallic stent insertion under fluoroscopic guidance for palliation of symptoms related to malignant gastroduodenal obstruction. MATERIALS AND METHODS Seventy-two patients (38 men, 34 women) aged 25–98 years (mean, 62 years) with duodenal ( n = 43), antropyloric ( n = 13), surgical gastrojejunostomy ( n = 10), or pyloroduodenal ( n = 6) malignant obstruction were referred for insertion of self-expanding metallic stents over a 6-year period. Stent insertion was performed with use of a peroral or transgastric approach when necessary ( n = 11). RESULTS Stents were successfully inserted in 70 of the 72 patients (97%) and provided symptom relief in 65 patients (90%). Inserted stents were mainly uncovered vascular ( n = 55) or enteral ( n = 10) Wallstents. One hundred eight stents were initially inserted: one, two, three, or four stents were indicated in 43, 17, nine, and one patient, respectively. Mean follow-up was 119 days (range, 4–513 days). Mean stent patency was 113 days (range, 4–513 days). Mean survival of patients was 120 days. During follow-up, stent obstruction occurred in seven patients as a result of tumoral overgrowth ( n = 5) or ingrowth ( n = 2). Complications occurred in 12 of the 72 patients (17%), including stent migration ( n = 8), stent fracture ( n = 1), duodenal perforation ( n = 1), and death related to general anesthesia ( n = 1). CONCLUSION Despite a significant complication rate, self-expanding metallic stent insertion under fluoroscopic guidance appears to be a feasible and useful technique in the palliative management of malignant gastroduodenal obstruction.

Resume La rupture de carcinome hepatocellulaire represente une complication relativement frequente et potentiellement fatale. Les situations cliniques sont differentes depuis l’hemorragie compensee jusqu’a la rupture peritoneale massive. Ceci pose souvent plusieurs problemes en pratique : retard au diagnostic, meconnaissance des differentes possibilites therapeutiques et de leur efficacite respective. Le diagnostic repose sur la scanographie. Le traitement initial est habituellement l’hemostase par embolisation, ce qui ne prejuge pas d’une autre prise en charge ulterieure en cas d’evolution favorable.