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Introduction Imaging plays a crucial role in the diagnosis, prognosis and follow-up of traumatic brain injury. Whereas computed tomography plays a pivotal role in the acute setting, magnetic resonance imaging is best suited to detect the true extent of traumatic brain injury, and more specifically diffuse axonal injury. Post-traumatic brain atrophy is a well-known complication of traumatic brain injury. Purpose This study investigated the correlation between diffuse axonal injury detected with fluid-attenuated inversion recovery and susceptibility-weighted imaging magnetic resonance imaging, post-traumatic brain atrophy and functional outcome (Glasgow outcome scale – extended). Materials and methods Twenty patients with a closed head injury and diffuse axonal injury detected with fluid-attenuated inversion recovery and susceptibility-weighted imaging were included. The total volumes of the diffuse axonal injury fluid-attenuated inversion recovery lesions were determined for each subject’s initial (Results The volumetric fluid-attenuated inversion recovery diffuse axonal injury lesion load showed a significant inverse correlation with functional outcome (Glasgow outcome scale – extended) ( r = −0.57; P = 0.0094) and white matter volume change ( r = −0.50; P = 0.027). In addition, white matter volume change correlated significantly with the Glasgow outcome scale – extended score ( P = 0.0072; r = 0.58). Moreover, there was a strong inverse correlation between longitudinal fluid-attenuated inversion recovery lesion volume change and whole brain volume change ( r = −0.63; P = 0.0028). No significant correlation existed between the number of diffuse axonal injury susceptibility-weighted imaging lesions, brain atrophy and functional outcome. Conclusions Volumetric analysis of diffuse axonal injury on fluid-attenuated inversion recovery imaging and automated brain atrophy calculation are potentially useful tools in the clinical management and follow-up of traumatic brain injury patients with diffuse axonal injury.

The aim of this study is to compare a qualitative and a quantitative assessment of brain diffusion-weighted imaging (DWI) in predicting outcome of comatose patients after cardiac arrest (CA). Two observers used a scoring template to analyze the DWI of 75 patients. A total of 13 regions were scored from 0 to 3 (0 = normal, 1 = probably normal, 2 = probably abnormal, 3 = definitely abnormal). The total cerebral cortex (TCC), the total deep grey nuclei (TDGN), the total brain stem, the total cerebellum, and the total brain score were calculated. Intra- and inter-observer variability were tested. The mean whole brain apparent diffusion coefficient (ADC) values and percentage of voxels below a specific ADC value cut-off were calculated. The data were correlated with clinical outcome (cerebral performance category score after 180 days, dichotomized in a score 1–2 with favorable outcome and score 3–5 with unfavorable outcome) using ROC analysis. Intra-observer variability was excellent for the TCC score (ICC 0.95 and 0.86) and the TDGN score (ICC 0.89 and 0.75). Inter-observer variability was good to excellent for total cerebral cortex score and total deep grey nuclei score in both the first (ICC 0.78 and 0.69) and third (ICC 0.86 and 0.83) image assessment. TCC and TDGN score show the best correlation with clinical outcome (highest AUC values 0.87 and 0.87). Quantitative parameters did not show good correlation with clinical outcome (AUC values 0.57 and 0.60). A qualitative assessment of brain DWI using a scoring template provides useful data regarding patient outcome while quantitative data appeared less reliable.

Background: Metastatic renal cell carcinoma (mRCC) patients with bone metastases (BM) are at high risk for skeletal related events and have a poorer outcome when treated with vascular endothelial g...

PURPOSE: To evaluate the predictive value of 7-week apparent diffusion coefficient change from baseline (ADCratio(7w)) at whole-body diffusion-weighted MRI (WB-DWI MRI) after one peptide receptor radionuclide therapy (PRRT) cycle to predict outcome in patients with metastatic neuroendocrine tumor (mNET). MATERIALS AND METHODS: From April 2009 to May 2012, participants in a prospective clinical trial investigating yttrium 90–DOTA Phe1-Tyr(3)-octreotide (DOTATOC) treatment for mNET (EudraCT no. 2008–007965–22) underwent WB-DWI MRI and gallium 68 ((68)Ga)–DOTATOC PET/CT before and 7 weeks after one PRRT cycle. ADCratio(7w) response was compared with the 7-week Response Evaluation Criteria in Solid Tumors version 1.1 and (68)Ga-DOTATOC PET/CT quantitative responses to predict overall survival (OS) and progression-free survival (PFS) with Cox regression analysis. RESULTS: Forty participants were analyzed (mean age, 60 years ± 11 [SD]; 21 men). Median PFS and OS were 10.5 months (range, 2–36 months) and 18 months (range, 3–81 months), respectively. Survival analysis showed significantly positive effects on PFS by age (hazard ratio [HR] = 0.96, P = .007), tumor grade (HR = 2.84, P = .006), Ki-67 index (HR = 1.05, P = .01), ADCratio(7w) of the least-responding lesion (ADCratio(7w-least)) (HR = 0.94, P < .001), and baseline mean standardized uptake values (SUV(mean)) (HR = 0.89, P = .02), with ADCratio(7w-least) and SUV(mean) remaining significant in multivariable analysis (P < .001, P = .02, respectively). There were significantly positive effects on OS by pretreatment lesion volume (HR = 1.004, P = .004), tumor grade (HR = 2.14, P = .04), Ki-67 index (HR = 1.05, P = .01), and ADCratio(7w-least) (HR = 0.97, P < .001), with pretreatment volume and ADCratio(7w-least) remaining significant at multivariable analysis (P = .005, P = .002, respectively). CONCLUSION: The ADCratio(7w) after start of PRRT for mNET was an independent predictor of patient outcome. Keywords: MR–Diffusion-Weighted Imaging, Radionuclide Therapy, Whole-Body Imaging, Metastases, Tumor Response, Treatment Effects EudraCT no. 2008-007965-22 © RSNA, 2022

To facilitate the development of new brain metastasis (BM) treatment, an easy-to-use and clinically relevant animal model with imaging platform is needed. Rhabdomyosarcoma BM was induced in WAG/Rij rats. Post-implantation surveillance and characterizations were systematically performed with multiparametric MRI including 3D T1 and T2 weighted imaging, diffusion-weighted imaging (DWI), T1 and T2 mapping, and perfusion-weighted imaging (PWI), which were validated by postmortem digital radiography (DR), µCT angiography and histopathology. The translational potential was exemplified by the application of a vascular disrupting agent (VDA). BM was successfully induced in most rats of both genders (18/20). Multiparametric MRI revealed significantly higher T2 value, pre-contrast-enhanced (preCE) T1 value, DWI-derived apparent diffusion coefficient (ADC) and CE ratio, but a lower post-contrast-enhanced (postCE) T1 value in BM lesions than in adjacent brain (p 0.01). PWI showed the dynamic and higher contrast agent uptake in the BM compared with the adjacent brain. DR, µCT and histopathology characterized the BM as hypervascular tumors. After VDA treatment, the BM showed drug-related perfusion changes and partial necrosis as evidenced by anatomical, functional MRI parameters and postmortem findings. The present BM model and imaging modalities represent a feasible and translational platform for developing BM-targeting therapeutics.

Background: Accurate staging of patients with gastric cancer is necessary for selection of the most appropriate and personalized therapy. Computed Tomography (CT) is currently used as primary staging tool, being widely available with a relatively high accuracy for the detection of parenchymal metastases, but with low sensitivity for the detection of peritoneal metastases. Magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) has a very high spatial and contrast resolution, suggesting a higher diagnostic performance in the detection of small peritoneal lesions. The aim of this study was to retrospectively evaluate the added value of whole-body diffusion-weighted MRI (WB-DWI/MRI) to CT for detection of peritoneal carcinomatosis (PC) and distant metastases in the preoperative staging of gastric cancer.Methods: This retrospective study included thirty-two patients with a suspicion of gastric cancer/recurrence, who underwent WB-DWI/MRI at 1.5 Tesla, in addition to CT of thorax and abdomen. Images were evaluated by two experienced abdominal radiologists in consensus. Histopathology, laparoscopy and/or 1-year follow-up were used as reference standard.Results: For overall tumor detection (n=32), CT sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) was 83.3%, 100%, 100% and 82.4% respectively. For WB-DWI/MRI these values were 100%, 92.9%, 94.7% and 100%, respectively. For staging (n=18) malignant lymph nodes and metastases, CT had a sensitivity, specificity/ PPV/ NPV of 50%/ 100%/ 100%/ 71.4%, and 15.4%/ 100%/ 100%/ 31.3% respectively. For WB-DWI/MRI, all values were 100%, for both malignant lymph nodes and metastases. WB-DWI/MRI was significantly better than CT in detecting tumor infiltration of the mesenteric root, serosal involvement of the small bowel and peritoneal metastases for which WB-DWI/MRI was correct in 100% of these cases, CT 0%.Conclusions: WB-DWI/MRI is highly accurate for diagnosis, staging and follow-up of patients with suspected gastric cancer. These results need to be confirmed in larger studies.

To better inform the next clinical trials of vascular disrupting agent combretastatin-A4-phosphate (CA4P) in patients with hepatic malignancies, this preclinical study aimed at evaluating CA4P therapeutic efficacy in rats with primary hepatocellular carcinomas (HCCs) of a full spectrum of differentiation and vascularity by magnetic resonance imaging (MRI), microangiography and histopathology. Ninety-six HCCs were raised in 25 rats by diethylnitrosamine gavage. Tumor growth was monitored by T2-/T1-weighted-MRI (T2WI, T1WI) using a 3.0 T scanner. Early vascular response and later intratumoral necrosis were detected by dynamic-contrast-enhanced (DCE) MRI and diffusion-weighted-imaging (DWI) before, 1 and 12 hr after CA4P iv-administration. In vivo MRI-findings were validated by postmortem-techniques. Multi-parametric MRI revealed rapid CA4P-induced tumor vascular shutdown within 1 hr, followed by variable intratumoral necrosis at 12 hr. Tumor volumes decreased by 10% at 1 hr (p

Breast cancer gene (BRCA) 1 and 2 mutations are frequently studied gene mutations (GM); the incidence of checkpoint kinase 2 (CHEK2) is increasing. We describe the imaging features of breast cancer (BC) in CHEK2 mutations, compared to BRCA 1 and 2 using mammography, ultrasound (US) and magnetic resonance imaging (MRI).Inclusion criteria were primary BC in GM carriers, treated in the same hospital. Age at diagnosis, histology, hormone receptor and human epidermal growth factor receptor 2 (HER2) status were retrieved. Mammography descriptors were mass, asymmetry and suspicious microcalcifications. The enhancement pattern (MRI), shape and border, architectural distortion, the presence of a hyperechoic rim and cystic complex structure (US) were documented. Analyses were performed using SAS software (version 9.4). Fishers' exact test was used to test associations between two categorical variables.In 191 women, 233 malignant lesions were diagnosed (78 in BRCA1, 109 in BRCA2, 46 in CHEK2). In CHEK2 carriers, mammographically, suspicious microcalcifications (54%) were more prevalent (BRCA2 (48%) and BRCA1 carriers (33%)) (p-value = 0.057) compared to mass lesions (35%). On US, lesions were most frequently ill-defined (86%) (p = 0.579) and irregular (94.5%) (p = 0.098) compared to BRCA2 (77% and 80% resp.) and BRCA1 carriers (71% and 72% resp.). On MRI, mass lesions showed a type 3 curve in CHEK2 (67%) compared to BRCA1 (36%) and BRCA2 (50%) (p = 0.056).Malignant radiological characteristics of breast cancer, more specifically suspicious microcalcifications, were more frequently seen in CHEK2 and BRCA2 compared to BRCA1 mutation carriers (without a significant difference) indicating the importance of mammography in follow-up of CHEK2 carriers.

To describe the added value of novel functional MRI techniques towards detection, staging, characterization, response monitoring and prognostication in gynaecological cancer.Functional MRI including diffusion-weighted imaging (DWI)-MRI and dynamic contrast-enhanced (DCE)-MRI adds structural, hemodynamic and physiological information to anatomical MRI. In endometrial and cervical cancer, the addition of DWI-MRI and DCE-MRI improves tumour detection as well as staging of uterine and extra-uterine pelvic spread. Quantitative assessment of DWI and DCE-MRI reflecting tissue properties of biological aggressiveness or treatment resistance may enable the prediction of risk of extra-uterine or extra-ovarian disease spread, predict risk of recurrence and assess treatment response. DWI shows high accuracy for detecting peritoneal metastases and allows for comprehensive staging of (recurrent) ovarian cancer following the clinical development of whole body DWI-MRI.The added value of DWI/DCE-MRI for characterization and staging of gynaecological malignancy is becoming increasingly established and may improve treatment stratification. Ongoing multicentre studies are expected to further consolidate its use in clinical routine. Quantitative evaluation of functional MRI may help in prognostication and risk stratification.

We sought to investigate anticancer efficacy of a vascular disrupting agent (VDA) combretastatin A-4 phosphate (CA4P) in relation to tumor size among hepatocellular carcinomas (HCCs) in rats using magnetic resonance imaging (MRI) and postmortem techniques. Nineteen rats with 43 chemically-induced HCCs of 2.8-20.9 mm in size on liver cirrhosis received CA4P intravenously at 10 mg/kg. Tumor-diameter was measured by T2-weighted imaging (T2WI) to define microcancers (< 5 mm) versus larger HCCs. Vascular responses and tissue necrosis were detected by diffusion-weighted imaging (DWI), contrast-enhanced T1-weighted imaging (CE-T1WI) and dynamic contrast enhanced (DCE-) MRI, which were validated by microangiography and histopathology. MRI revealed nearly complete necrosis in 5 out of 7 micro-HCCs, but diverse therapeutic necrosis in larger HCCs with a positive correlation with tumor size. Necrosis in micro-HCCs was 36.9% more than that in larger HCCs. While increased diffusion coefficient (ADCdiff) suggested tumor necrosis, perfusion coefficient (ADCperf) indicated sharply decreased blood perfusion in cirrhotic liver together with a reduction in micro-HCCs. DCE revealed lowered tumor blood flow from intravascular into extravascular extracellular space (EES). Microangiography and histopathology revealed hypo- and hypervascularity in 4 and 3 micro-HCCs, massive, partial and minor degrees of tumoral necrosis in 5, 1 and 1 micro-HCCs respectively, and patchy necrotic foci in cirrhotic liver. CD34-PAS staining implicated that poorly vascularized micro-HCCs growing on liver cirrhosis tended to respond better to CA4P treatment. In this study, more complete CA4P-response occurred unexpectedly in micro-HCCs in rats, along with CA4P-induced necrotic foci in cirrhotic liver. These may help to plan clinical applications of VDAs in patients with HCCs and liver cirrhosis. ispartof: Oncotarget vol:8 issue:33 pages:55204-55215 ispartof: location:United States status: published

Age-related brain atrophy is a common finding, but neurodegenerative diseases such as Alzheimer's disease are associated with accelerated atrophy of the medial temporal lobe. In current practice for brain atrophy evaluation, several rating scales are being used such as the medial temporal atrophy (MTA), global cortical atrophy-frontal subscale (GCA-F) and posterior atrophy (PA) scales. Practical cut-offs to differentiate between normal and advanced brain atrophy are needed, because of their possible usefulness as a biomarker. A retrospective study was performed over a 1-year period resulting in a total of 79 subjects [27 patients with Alzheimer's disease (AD), 27 patients with minimal cognitive impairment (MCI) and 25 control subjects]. The MTA, GCA-F and PA scales were applied blinded and independent by two raters. Possible age- and disease-related cut-offs were computed. The MTA scale showed significantly better diagnostic performances and inter-rater agreement than the PA and GCA-F scales. We could not confirm the suggested MTA cut-off for each decade. However, an MTA score of >1 and >1.75 was considered pathological, respectively, in the population under and over 70 years. MTA can be of use in making distinction between age-related atrophy and abnormal increase of atrophy. Systematic assessment of regional brain atrophy through the use of MTA in MRI images could be a useful biomarker in aiding the early diagnosis of Alzheimer's disease.

Despite excellent per-lesion performance for peritoneal staging, the additional clinical value of diffusion-weighted magnetic resonance imaging (DWI/MRI) compared to computed tomography (CT) remains to be established in ovarian cancer. Our purpose was to evaluate whole body (WB)-DWI/MRI for diagnosis, staging and operability assessment of patients suspected for ovarian cancer compared to CT. One hundred and sixty-one patients suspected for ovarian carcinoma underwent 3 T WB-DWI/MRI and contrast-enhanced CT. WB-DWI/MRI and CT were compared for confirmation of the malignant nature and primary origin of the ovarian mass, Fédération Internationale de Gynécologie et d'Obstétrique (FIGO) staging and prediction of incomplete resection using institutional operability criteria. Interobserver agreement between two readers was determined for WB-DWI/MRI and CT. WB-DWI/MRI showed a significantly higher accuracy than CT (93 versus 82%, p = 0.001) to confirm the malignant nature of the ovarian mass and correctly identified 26 of 32 (81%) cancers of non-ovarian origin compared to 10/32 (31%) for CT (p < 0.001). WB-DWI/MRI assigned more ovarian carcinoma patients to the correct FIGO stage (82/94, 87%) compared with CT (33/94, 35%). For prediction of incomplete resection, WB-DWI/MRI showed significantly higher sensitivity (94 versus 66%), specificity (97.7 versus 77.3%) and accuracy (95.7 versus 71.3%) compared to CT (p < 0.001). Interobserver agreement was almost perfect (κ = 0.90) for WB-DWI/MRI and moderate (κ = 0.52) for CT for prediction of incomplete resection. WB-DWI/MRI was superior to CT for primary tumour characterisation, staging and prediction of incomplete resection in patients suspected for ovarian cancer

PURPOSE: To evaluate the prognostic utility of apparent diffusion coefficient (ADC) changes at whole-body diffusion-weighted (WB-DW) MRI after one treatment cycle for aggressive non-Hodgkin lymphoma (NHL) compared with response assessment at interim and end-of-treatment fluorine 18 ((18)F) fluorodeoxyglucose (FDG) PET/CT. MATERIALS AND METHODS: This was a secondary analysis of a prospective study (ClinicalTrials.gov identifier: NCT01231269) in which participants with aggressive NHL were recruited between March 2011 and April 2015 and underwent WB-DW MRI before and after one cycle of immunochemotherapy. Volunteers were recruited for test-retest WB-DW MRI (ClinicalTrials.gov identifier: NCT01231282) to assess ADC measurement repeatability. Response assessment was based on ADC change after one treatment cycle at WB-DW MRI and Deauville criteria at (18)F-FDG PET/CT. To evaluate prognostic factors of disease-free survival (DFS), Kaplan-Meier survival analysis and univariable and multivariable Cox regression were performed; intraclass correlation coefficient (ICC) and mean difference with limits of agreement were calculated to determine inter- and intraobserver repeatability of ADC measurements. RESULTS: Forty-five patients (mean age, 58 years ± 17 [standard deviation]; 31 men) and nine volunteers (mean age, 22 years ± 3; seven men) were enrolled. Median DFS was 48 months (range, 2–48 months). Outcome prediction accuracy was 86.7% (39 of 45), 71.4% (30 of 42), and 73.8% (31 of 42) for WB-DW MRI and interim and end-of-treatment (18)F-FDG PET/CT, respectively. WB-DW MRI (hazard ratio [HR], 17.8; P < .001) and interim (HR, 5; P = .008) and end-of-treatment (HR, 4.3; P = .017) (18)F-FDG PET/CT were prognostic of DFS. After multivariable analysis, WB-DW MRI remained an independent predictor of outcome (HR, 26.8; P = .002). Intra- and interobserver agreement for ADC measurements were excellent (ICC = 0.85–0.99). CONCLUSION: Quantitative WB-DW MRI after only one cycle of immunochemotherapy predicts DFS in aggressive NHL and is noninferior to routinely performed interim and end-of-treatment (18)F-FDG PET/CT. Keywords: MR-Diffusion Weighted Imaging, Lymphoma, Oncology, Tumor Response, Whole-Body Imaging Supplemental material is available for this article. © RSNA, 2021

OBJECTIVE: Targeted magnetic resonance/ultrasound fusion prostate biopsy has been shown to improve the detection of high-grade prostate cancer and to reduce sampling errors. Our objective is to assess MR-TRUS targeted fusion biopsy versus standard biopsy for the detection of clinically significant tumors. MATERIALS AND METHODS: Patients were referred for abnormal digital rectal examination (DRE) or risen prostate-specific antigen (PSA). If an MRI-visible lesion was detected, they were included in the study. In total, 102 men underwent MRI followed by MR-TRUS fusion biopsy between November 2014 and January 2016. Tumor grading was done with the clinical relevance in mind; a cutoff was used at Gleason 7 or higher. Standard biopsy results were collected from clinical practice during 2005 at the same institution to provide baseline values. RESULTS: A comparable rate of prostate cancer is found whether sampling is done at random (42.4%) or with the use of fusion biopsy (44.1%). However, these percentages are histologically different: fewer low-grade tumors are detected with MR-TRUS fusion biopsy (-19.1%), while more high-grade tumors are diagnosed (+26%). If there is an ultrasound-visible lesion in the prostate, the gain of combined MRI and fusion biopsy is less impressive. CONCLUSION: Fusion biopsy can provide more accurate information for optimal patient management, as it detects a higher percentage of high-grade prostate cancers than random sampling. Furthermore, nonrelevant tumors are less commonly detected using fusion biopsy. ispartof: Journal of the Belgian Society of Radiology vol:100 issue:1 pages:1-9 ispartof: location:England status: published

BACKGROUND: Correct staging of patients with colorectal cancer is of utmost importance for the prediction of operability. Although computed tomography (CT) has a good overall performance, estimation of peritoneal cancer spread is a known weakness, a problem that cannot always be overcome by Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT); especially in infiltrative and miliary disease spread. Due to its high spatial and contrast resolution magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) might have a better performance. Our aim was to evaluate the added value of whole-body diffusion-weighted MRI (WB-DWI/MRI) to CT for prediction of peritoneal cancer spread and operability assessment in colorectal cancer patients with clinically suspected peritoneal carcinomatosis (PC). METHODS: This institutional review board approved retrospective study included sixty colorectal cancer patients who underwent WB-DWI/MRI in addition to CT for clinically suspected peritoneal metastases. WB-DWI/MRI and CT were assessed for detecting PC following the peritoneal cancer index (PCI), determination of PCI-score categorized as PC 15, detection of nodal and distant metastases and estimation of overall operability. Histopathology after surgery and biopsy and/or 6 months follow-up were used as reference standard. RESULTS: For detection of PC, CT had 43.2% sensitivity, 95.6% specificity, 84.5% positive predictive value (PPV) and 75.2% negative predictive value (NPV). WB-DWI/MRI had 97.8% sensitivity, 93.2% specificity, 88.9% PPV and 98.7% NPV. WB-DWI/MRI enabled better detection of inoperable distant metastases (all 12 patients) than CT (2/12 patients) and significantly improved prediction of PCI category [WB-DWI/MRI PCI 15: 16/17 patients (94.1%) versus CT PCI 15: 2/17 patients (11.8%); p

Technologic advances enable performance of diffusion-weighted imaging (DWI) at ultrahigh b-values, where standard monoexponential model analysis may not apply. Rather, non-Gaussian water diffusion properties emerge, which in cellular tissues are, in part, influenced by the intracellular environment that is not well evaluated by conventional DWI. The novel technique, diffusion kurtosis imaging (DKI), enables characterization of non-Gaussian water diffusion behavior. More advanced mathematical curve fitting of the signal intensity decay curve using the DKI model provides an additional parameter Kapp that presumably reflects heterogeneity and irregularity of cellular microstructure, as well as the amount of interfaces within cellular tissues. Although largely applied for neural applications over the past decade, a small number of studies have recently explored DKI outside the brain. The most investigated organ is the prostate, with preliminary studies suggesting improved tumor detection and grading using DKI. Although still largely in the research phase, DKI is being explored in wider clinical settings. When assessing extracranial applications of DKI, careful attention to details with which body radiologists may currently be unfamiliar is important to ensure reliable results. Accordingly, a robust understanding of DKI is necessary for radiologists to better understand the meaning of DKI-derived metrics in the context of different tumors and how these metrics vary between tumor types and in response to treatment. In this review, we outline DKI principles, propose biostructural basis for observations, provide a comparison with standard monoexponential fitting and the apparent diffusion coefficient, report on extracranial clinical investigations to date, and recommend technical considerations for implementation in body imaging.

This paper introduces a hybrid method for performing detection studies in projection image based modalities, based on image acquisitions of target objects and patients. The method was used to compare 2D mammography and digital breast tomosynthesis (DBT) in terms of the detection performance of spherical densities and microcalcifications. The method starts with the acquisition of spheres of different glandular equivalent densities and microcalcifications of different sizes immersed in a homogeneous breast tissue simulating medium. These target objects are then segmented and the subsequent templates are fused in projection images of patients and processed or reconstructed. This results in hybrid images with true mammographic anatomy and clinically relevant target objects, ready for use in observer studies. The detection study of spherical densities used 108 normal and 178 hybrid 2D and DBT images; 156 normal and 321 hybrid images were used for the microcalcifications. Seven observers scored the presence/absence of the spheres/microcalcifications in a square region via a 5-point confidence rating scale. Detection performance in 2D and DBT was compared via ROC analysis with sub-analyses for the density of the spheres, microcalcification size, breast thickness and z-position. The study was performed on a Siemens Inspiration tomosynthesis system using patient acquisitions with an average age of 58 years and an average breast thickness of 53 mm providing mean glandular doses of 1.06 mGy (2D) and 2.39 mGy (DBT). Study results showed that breast tomosynthesis (AUC = 0.973) outperformed 2D (AUC = 0.831) for the detection of spheres (p

AIM: To compare therapeutic responses of a vascular-disrupting-agent, combretastatin-A4-phosphate (CA4P), among hepatocellular carcinomas (HCCs) and implanted rhabdomyosarcoma (R1) in the same rats by magnetic-resonance-imaging (MRI), microangiography and histopathology. METHODS: Thirty-six HCCs were created by diethylnitrosamine gavage in 14 rats that were also intrahepatically implanted with one R1 per rat as monitored by T2-/T1-weighted images (T2WI/T1WI) on a 3.0T clinical MRI-scanner. Vascular response and tumoral necrosis were detected by dynamic contrast-enhanced (DCE-) and CE-MRI before, 1 h after and 12 h after CA4P iv at 10 mg/kg (treatment group n = 7) or phosphate-buffered saline at 1.0 mL/kg (control group n = 7). Tumor blood supply was calculated by a semiquantitative DCE parameter of area under the time signal intensity curve (AUC30). In vivo MRI findings were verified by postmortem techniques. RESULTS: On CE-T1WIs, unlike the negative response in all tumors of control animals, in treatment group CA4P caused rapid extensive vascular shutdown in all R1-tumors, but mildly or spottily in HCCs at 1 h. Consequently, tumor necrosis occurred massively in R1-tumors but patchily in HCCs at 12 h. AUC30 revealed vascular closure (66%) in R1-tumors at 1 h (P < 0.05), followed by further perfusion decrease at 12 h (P < 0.01), while less significant vascular clogging occurred in HCCs. Histomorphologically, CA4P induced more extensive necrosis in R1-tumors (92.6%) than in HCCs (50.2%) (P < 0.01); tumor vascularity heterogeneously scored +~+++ in HCCs but homogeneously scored ++ in R1-tumors. CONCLUSION: This study suggests superior performance of CA4P in metastatic over primary liver cancers, which could guide future clinical applications of vascular-disrupting-agents.​. ispartof: World Journal of Gastroenterology vol:24 issue:25 pages:2710-2721 ispartof: location:United States status: published

To evaluate the feasibility of whole-body diffusion-weighted MRI (WB-DWI/MRI) for detecting primary tumour, nodal and distant metastases in pregnant women with cancer. Twenty pregnant patients underwent WB-DWI/MRI in additional to conventional imaging. Reproducibility of WB-DWI/MRI between two readers was evaluated using Cohen’s κ statistics and accuracy was compared to conventional imaging for assessing primary tumour site, nodal and visceral metastases. Both WB-DWI/MRI readers showed good–very good agreement for lesion detection (primary lesions: κ=1; lymph nodes: κ=0.89; distant metastases: κ=0.61). Eight (40 %) patients were upstaged after WB-DWI/MRI. For nodal metastases, WB-DWI/MRI showed 100 % (95 % CI: 83.2–100) sensitivity for both readers with specificity of 99.4 % (96.9–100) and 100 % (80.5–100) for readers 1 and 2, respectively. For distant metastases, WB-DWI/MRI showed 66.7 % (9.4–99.2) and 100 % (29.2–100) sensitivity and specificity of 94.1 % (71.3–99.9) and 100 % (80.5–100) for readers 1 and 2, respectively. Conventional imaging showed sensitivity of 50 % (27.2-72.8) and 33.3 % (0.8–90.6); specificity of 100 % (98–100) and 100 % (80.5–100), for nodal and distant metastases respectively. WB-DWI/MRI is feasible for single-step non-invasive staging of cancer during pregnancy with additional value for conventional imaging procedures. • In our study, WB-DWI/MRI was more accurate than conventional imaging during pregnancy. • WB-DWI/MRI improves diagnostic assessment of patients with cancer during pregnancy. • Accurate imaging and oncologic staging improves treatment and outcome.

Correct staging and treatment initiation in malignant lymphoma depends on accurate lymph node characterization. However, nodal assessment based on conventional and diffusion-weighted (DWI) MRI remains challenging, particularly in smaller nodes.To evaluate first-order apparent diffusion coefficient (ADC) texture parameters compared to mean ADC for lymph node characterization in non-Hodgkin lymphoma (NHL) using whole-body DWI (WB-DWI).Retrospective.Twenty-eight patients with NHL.3T whole-body DWI using two b-values (0-1000 s/mmRegions of interest were drawn on the three most hyperintense lymph nodes on b1000-images, irrespective of size, in all nodal body regions. Diagnostic performance of mean ADC (ADCBenign and malignant nodes were compared using Mann-Whitney U-tests with 18-Fluoro-deoxyglucose positron emission tomography computed tomography and bone marrow biopsy as reference standard. Receiver operating characteristic analyses were performed to determine cutoff values and calculate sensitivity, specificity, accuracy, and positive and negative predictive value (PPV, NPV).ADCFirst-order ADC texture analysis with WB-DWI improved lymph node characterization compared to ADC3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:897-906.

Total kidney volume, measured by magnetic resonance imaging (MRI), is a validated disease progression marker in adults with autosomal dominant polycystic kidney disease (ADPKD). However, in childhood, MRI is burdensome, explaining the need for alternatives. Kidney volume (KV) was evaluated in 30 children with ADPKD, using three-dimensional ultrasound (3DUS), applying the ellipsoid method and manual contouring (KV3DUS-ellipsoid, KV3DUS-contour respectively); manual contouring on MRI (KVMRI), and the ellipsoid method on two-dimensional ultrasound (2DUS, KV2DUS). Correlations and differences were evaluated using Pearson’s r and Wilcoxon signed-rank tests, and variability using Bland–Altman plots. All ultrasound volumetry methods showed significantly lower mean (± SD) KV (mL), compared with MRI—KV2DUS: 159 (±101); K3DUS-ellipsoid: 169 (±105); KV3DUS-contour: 185 (±110); KVMRI: 206 (±130); all p

The purpose of this study was to retrospectively assess the incidence of bowel wall oedema on computed tomography (CT) in patients with renal cell carcinoma (RCC) treated with sunitinib, and to investigate its association with diarrhoea. We conducted a retrospective analysis of all RCC patients treated with sunitinib at our hospital between December 2005 and December 2011. The presence or absence of bowel wall oedema on these CT examinations was scored. The presence of diarrhoea preceding, during, or after sunitinib treatment was identified from the patient files and retrospectively graded. For 54 of 87 patients, bowel wall oedema was present on at least one CT examination. Of these 54 patients, the right-sided colonic segment was affected in 87 %. Diarrhoea was the most common reported adverse event during treatment, with 58 patients (67 %) having grade 1/2 diarrhoea and 9 patients (10 %) having grade 3. There was a statistically significant correlation between the incidence of CT-scored bowel oedema and diarrhoea during sunitinib treatment (P = 0.004). This study shows a very high incidence of bowel wall oedema and a strong correlation between the incidence of bowel wall oedema and diarrhoea in patients treated with sunitinib. • Sunitinib is routinely used in patients with advanced renal cell carcinoma. • Diarrhoea is the most common reported adverse event during sunitinib treatment. • Incidence of bowel oedema and diarrhoea during sunitinib treatment is correlated. • Radiologists should avoid misinterpretation of bowel oedema as infectious colitis.

Introduction In head and neck squamous cell carcinoma (HNSCC) the ability to anticipate an individual patient's outcome is very valuable. With this study we wanted to assess the prognostic value of pretreatment apparent diffusion coefficient (ADC) in a large patient population and integrate it into a multivariable prognostic model. Methods From 2004 to 2010 175 patients with pathology proven HNSCC were included in this study. All patients underwent a pretreatment MRI with diffusion weighted imaging (DWI) using six b -values. For each tumor, three ADC values were calculated using different b -value combinations: ADC low ( b 0–50–100s/mm 2 ), ADC high ( b 500–750–1000s/mm 2 ) and ADC avg (all b -values). The clinical and radiological variables included: tumor and nodal volume, tumor location and age. Disease recurrence was analyzed using competing risk regression. A prognostic model for disease recurrence was developed, and internal validation was performed using bootstrapping and by dividing patients in three equal sized groups based on prognosis. Results One hundred and sixty-one patients were eligible for analysis. Median follow-up was 50months (range 4–86). A total of 67 patients experienced disease recurrence during follow-up (42%). ADC high was a prognostic factor for disease recurrence (adjusted hazard ratio: 1.14 per 10 –4 mm 2 /s, 95% CI 1.04–1.25). Harrell's c-index of the multivariable prognostic model was 0.62 (95% CI 0.56–0.70) after internal validation. The validated 3-year disease recurrence rates for the groups with worst, intermediate, and best prognosis were 56%, 33% and 31% respectively. Conclusion Pretreatment ADC value derived from high b -values is an independent prognostic factor in HNSCC and increases the performance of a multivariable prognostic model in addition to known clinical and radiological variables. Integration of other biomarkers and external validation is necessary to ensure its clinical applicability.

The 1-month apparent diffusion coefficient ratio after initial transcatheter arterial chemoembolization (TACE) was an independent predictor of progression-free survival; the stronger association between response at 1-month diffusion-weighted (DW) imaging and PFS compared with Response Evaluation Criteria in Solid Tumors (RECIST), European Association for the Study of the Liver criteria, and modified RECIST suggests that DW imaging may be a more reliable response marker after a single TACE procedure.

In head and neck cancer, diffusion weighted MRI (DWI) can predict response early during treatment. Treatment-induced changes and DWI-specific artifacts hinder an accurate registration between apparent diffusion coefficient (ADC) maps. The aim of the study was to develop a registration tool which calculates and visualizes regional changes in ADC.Twenty patients with stage IV HNC treated with primary radiotherapy received an MRI including DWI before and early during treatment. Markers were manually placed at anatomical landmarks on the different modalities at both time points. A registration method, consisting of a fully automatic rigid and nonrigid registration and two semi-automatic thin-plate spline (TPS) warps was developed and applied to the image sets. After each registration step the mean registration errors were calculated and ΔADC was compared between good and poor responders.Adding the TPS warps significantly reduced the registration error (in mm, 6.3 ± 6.2 vs 3.2 ± 3.3 mm, p0.001). After the marker based registration the median ΔADC in poor responders was significantly lower than in good responders (7% vs. 21%; p0.001).This registration method allowed for a significant reduction of the mean registration error. Furthermore the voxel-wise calculation of the ΔADC early during radiotherapy allowed for a visualization of the regional differences of ΔADC within the tumor.

We assessed the diagnostic accuracy of diffusion kurtosis imaging (DKI), dynamic susceptibility-weighted contrast-enhanced (DSC) MRI, and short echo time chemical shift imaging (CSI) for grading gliomas. In this prospective study, 35 patients with cerebral gliomas underwent DKI, DSC, and CSI on a 3 T MR scanner. Diffusion parameters were mean diffusivity (MD), fractional anisotropy, and mean kurtosis (MK). Perfusion parameters were mean relative regional cerebral blood volume (rrCBV), mean relative regional cerebral blood flow (rrCBF), mean transit time, and relative decrease ratio (rDR). The diffusion and perfusion parameters along with 12 CSI metabolite ratios were compared among 22 high-grade gliomas and 14 low-grade gliomas (Mann-Whitney U-test, P < .05). Classification accuracy was determined with a linear discriminant analysis for each MR modality independently. Furthermore, the performance of a multimodal analysis is reported, using a decision-tree rule combining the statistically significant DKI, DSC-MRI, and CSI parameters with the lowest P-value. The proposed classifiers were validated on a set of subsequently acquired data from 19 clinical patients. Statistically significant differences among tumor grades were shown for MK, MD, mean rrCBV, mean rrCBF, rDR, lipids over total choline, lipids over creatine, sum of myo-inositol, and sum of creatine. DSC-MRI proved to be the modality with the best performance when comparing modalities individually, while the multimodal decision tree proved to be most accurate in predicting tumor grade, with a performance of 86%. Combining information from DKI, DSC-MRI, and CSI increases diagnostic accuracy to differentiate low- from high-grade gliomas, possibly providing diagnosis for the individual patient.

To evaluate whole-body MRI with diffusion-weighted sequence (WB-DWI/MRI) for staging and assessing operability compared with CT and FDG-PET/CT in patients with suspected ovarian cancer. Thirty-two patients underwent 3-T WB-DWI/MRI, (18) F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) and CT before diagnostic open laparoscopy (DOL). Imaging findings for tumour characterisation, peritoneal and retroperitoneal staging were correlated with histopathology after DOL and/or open surgery. For distant metastases, FDG-PET/CT or image-guided biopsies were the reference standards. For tumour characterisation and peritoneal staging, WB-DWI/MRI was compared with CT and FDG-PET/CT. Interobserver agreement for WB-DWI/MRI was determined. WB-DWI/MRI showed 94 % accuracy for primary tumour characterisation compared with 88 % for CT and 94 % for FDG-PET/CT. WB-DWI/MRI showed higher accuracy of 91 % for peritoneal staging compared with CT (75 %) and FDG-PET/CT (71 %). WB-DWI/MRI and FDG-PET/CT showed higher accuracy of 87 % for detecting retroperitoneal lymphadenopathies compared with CT (71 %). WB-DWI/MRI showed excellent correlation with FDG-PET/CT (kappa = 1.00) for detecting distant metastases compared with CT (kappa = 0.34). Interobserver agreement was moderate to almost perfect (kappa = 0.58-0.91). WB-DWI/MRI shows high accuracy for characterising primary tumours, peritoneal and distant staging compared with CT and FDG-PET/CT and may be valuable for assessing operability in ovarian cancer patients. aEuro cent Whole-body MRI with diffusion weighting (WB-DWI/MRI) helps to assess the operability of suspected ovarian cancer. aEuro cent Interobserver agreement is good for primary tumour characterisation, peritoneal and distant staging. aEuro cent WB-DWI/MRI improves mesenteric/serosal metastatic spread assessment compared with CT and FDG-PET/CT. aEuro cent Retroperitoneal/cervical-thoracic nodal staging using qualitative DWI criteria was reasonably accurate. aEuro cent WB-DWI/MRI and FDG-PET/CT showed the highest diagnostic impact for detecting thoracic metastases

To evaluate the diagnostic accuracy of dynamic contrast-enhanced (DCE) magnetic resonance (MR) and diffusion-weighted imaging (DWI) sequences for defining benignity or malignancy of solitary pulmonary lesions (SPL).First, 54 consecutive patients with SPL, clinically staged (CT and PET or integrated PET-CT) as N0M0, were included in this prospective study. An additional 3-Tesla MR examination including DCE and DWI was performed 1 day before the surgical procedure. Histopathology of the surgical specimen served as the standard of reference. Subsequently, this functional method of SPL characterisation was validated with a second cohort of 54 patients.In the feasibility group, 11 benign and 43 malignant SPL were included. Using the combination of conventional MR sequences with visual interpretation of DCE-MR curves resulted in a sensitivity, specificity and accuracy of 100%, 55% and 91%, respectively. These results can be improved by DWI (with a cut-off value of 1.52 × 10(-3) mm(2)/s for ADChigh) leading to a sensitivity, specificity and accuracy of 98%, 82% and 94%, respectively. In the validation group these results were confirmed.Visual DCE-MR-based curve interpretation can be used for initial differentiation of benign from malignant SPL, while additional quantitative DWI-based interpretation can further improve the specificity.• Magnetic resonance imaging is increasingly being used to help differentiate lung lesions. • Solitary pulmonary lesions (SPL) are accurately characterised by combining DCE-MRI and DWI. • Visual DCE-MRI assessment facilitates the diagnostic throughput in patients with SPL. • DWI provides additional information in inconclusive DCE-MRI (type B pattern).

To retrospectively analyze the accuracy of simplified multiparametric MRI at 1.5 T for local staging by using whole-mount-section histopathological analysis as the standard of reference.123 consecutive patients underwent T2 weighted, T1 weighted and diffusion-weighted MRI without endorectal coil prior to radical prostatectomy. The accuracy of predicting extracapsular extension (ECE) (T3a) was assessed using direct signs or the combination of direct and indirect signs of extraprostatic extension. The accuracy of predicting seminal vesicle invasion (T3b) was evaluated, taking into account different routes of seminal vesicle involvement. Finally, adjacent organ invasion (T4) was evaluated in this patient population.Histopathology showed T3a, T3b and T4 in 61, 28 and 9 cases, respectively. The use of direct signs of extraprostatic extension showed a sensitivity of 57.4% and specificity of 91.9%. The combination of direct signs and indirect signs improved sensitivity (85.2%) at the expense of moderate loss of specificity (83.9%). MR sensitivity for the detection of seminal vesicle invasion was low (53.6%); however, it was dependent on the route of seminal vesicle tumour infiltration. MR sensitivity and specificity for adjacent organ invasion were 88.9% and 99.1%.Simplified MRI study at 1.5 T provides a relatively high sensitivity for detecting ECE (T3a) when using the combination of indirect and direct signs. However, this high sensitivity reading is at the cost of a moderate loss of specificity. Invasion of the seminal vesicles (T3b) occurs most often along the ejaculatory duct complex with low MR sensitivity.Simplified MRI study at 1.5 T without endorectal coil could be used for the local T staging of prostate cancer.

Purpose: To prospectively evaluate multiparametric magnetic resonance imaging (MRI) for accurate localization of intraprostatic tumor nodules, with whole-mount histopathology as the gold standard. Materials and Methods: Seventy-five patients with biopsy-proven, intermediate, and high-risk prostate cancer underwent preoperative T2-weighted (T2w), dynamic contrast-enhanced (DCE) and diffusion-weighted (DW) MRI at 1.5T. Localization of suspicious lesions was recorded for each of 24 standardized regions of interest on the different MR images and correlated with the pathologic findings. Generalized estimating equations (GEE) were used to estimate the sensitivity, specificity, accuracy, positive, and negative predictive value for every MRI modality, as well as to evaluate the influence of Gleason score and pT-stage. Tumor volume measurements on histopathological specimens were correlated with those on the different MR modalities (Pearson correlation). Results: DW MRI had the highest sensitivity for tumor localization (31.1% vs. 27.4% vs. 44.5% for T2w, DCE, and DW MRI, respectively; P < 0.005), with more aggressive or more advanced tumors being more easily detected with this imaging modality. Significantly higher sensitivity values were obtained for the combination of T2w, DCE, and DW MRI (58.8%) as compared to each modality alone or any combination of two modalities (P < 0.0001). Tumor volume can most accurately be assessed by means of DW MRI (r = 0.75; P < 0.0001). Conclusion: Combining T2w, DCE, and DW imaging significantly improves prostate cancer localization. J. Magn. Reson. Imaging 2013;37:1392–1401. © 2012 Wiley Periodicals, Inc.

To investigate the use of diffusion-weighted (DW) imaging for differentiating benign lesions from malignant pleural disease (MPD) and to retrospectively assess dynamic contrast material-enhanced (DCE) magnetic resonance (MR) imaging acquisitions to find out whether combining these measurements with DW imaging could improve the diagnostic value of DW imaging.This study was approved by the local ethics committee, and all patients provided written informed consent. Thirty-one consecutive patients with pleural abnormalities suspicious for MPD underwent whole-body positron emission tomography (PET)/computed tomography (CT) and thorax MR examinations. Diagnostic thoracoscopy with histopathologic analysis of pleural biopsies served as the reference standard. First-line evaluation of each suspicious lesion was performed by using the apparent diffusion coefficient (ADC) calculated from the DW image, and the optimal cutoff value was found by using receiver operating characteristic curve analysis. Afterward, DCE MR imaging data were used to improve the diagnosis in the range of ADCs where DW imaging results were equivocal.Sensitivity, specificity, and accuracy of PET/CT for diagnosis of MPD were 100%, 35.3%, and 64.5%. The optimal ADC threshold to differentiate benign lesions from MPD with DW MR imaging was 1.52 × 10(-3) mm(2)/sec, with sensitivity, specificity, and accuracy of 71.4%, 100%, and 87.1%, respectively. This result could be improved to 92.8%, 94.1%, and 93.5%, respectively, when DCE MR imaging data were included in those cases where ADC was between 1.52 and 2.00 × 10(-3) mm(2)/sec. A total of 20 patients had disease diagnosed correctly, nine had disease diagnosed incorrectly, and two cases were undetermined with PET/CT. DW imaging helped stage disease correctly in 27 patients and incorrectly in four. The undetermined cases at PET/CT were correctly diagnosed at MR imaging.DW imaging is a promising tool for differentiating MPD from benign lesions, with high accuracy, and supplementation with DCE MR imaging seems to further improve sensitivity.

Purpose: To assess the diagnostic accuracy of diffusion kurtosis magnetic resonance imaging parameters in grading gliomas. Materials and Methods: The institutional review board approved this prospective study, and informed consent was obtained from all patients. Diffusion parametersmean diffusivity (MD), fractional anisotropy (FA), mean kurtosis, and radial and axial kurtosiswere compared in the solid parts of 17 high-grade gliomas and 11 low-grade gliomas (P

Diffusion weighted (DW) magnetic resonance (MR) imaging has a large number of potential clinical applications in the female and male pelvis and can easily be added to any routine MR protocol. In the female pelvis DW imaging allows improvement of staging in endometrial and cervical cancer especially in locally advanced disease and in patients in whom contrast medium administration should be avoided. It can also be helpful in characterizing complex adnexal masses and in depicting recurrent tumor after treatment of various gynecologic malignancies. DW imaging shows promising results in monitoring treatment response in patients undergoing radiation therapy of cervical cancer. An increase in apparent diffusion coefficient (ADC) values of responders precedes changes in size and may therefore allow early assessment of treatment success. In the male pelvis the detection of prostate cancer in the peripheral zone is relatively easier than in the central gland based on the underlying ADC values whereas overlapping values reported in the central gland still need further research. DW imaging might also be applied in the noninvasive evaluation of bladder cancer to differentiate between superficial and muscle invasive tumors. Initial promising results have been reported in differentiating benign from malignant pelvic lymph nodes based on the ADC values; however larger scale studies will be needed to allow the detection of lymph node metastases in an individual patient. Prerequisites for successfully performing DW imaging of the female and male pelvis are standardization of the DW imaging technique including the choice of b values administration of an antiperistaltic drug and comparison of DW findings with those of morphologic MR imaging. © RSNA 2012.

To examine the feasibility and results of calculating the volume of lumbar vertebral bodies in normal patients and patients with suspected hypoplasia of L5. Lumbar multi-detector CT was performed in 38 patients with bilateral spondylolysis and hypoplasia of L5 and in 38 normal patients. Lumbar vertebral body volume of L3, L4 and L5 was measured by CT volumetry with a semi-automated program, created with MeVisLab. In the control group, the average vertebral body volume (in cubic centimeters) of L3 was 35.93 (±7.33), 36.34 (±7.13) for L4 and 34.63 (±6.88) for L5. In patients with suspected hypoplasia L5 the average body volume (in cubic centimeters) of L3 was 36.85 (±7.37), 36.90 (±6.99) for L4 and 33.14 (±6.57) for L5. The difference in mean vertebral body volume for L3, L4 and L5 between both groups was statistically not significant. However, there was a statistically significant difference of the ratio L5/L4 (P

Purpose To evaluate diffusion-weighted imaging (DWI) for assessment of treatment response in head and neck squamous cell carcinoma (HNSCC) three weeks after the end of chemoradiotherapy (CRT). Methods and Materials Twenty-nine patients with HNSCC underwent magnetic resonance imaging (MRI) prior to and 3 weeks after CRT, including T 2 -weighted and pre- and postcontrast T 1 -weighted sequences and an echo-planar DWI sequence with six b values (0 to 1,000 s/mm 2 ), from which the apparent diffusion coefficient (ADC) was calculated. ADC changes 3 weeks posttreatment compared to baseline (∆ADC) between responding and nonresponding primary lesions and adenopathies were correlated with 2 years locoregional control and compared with a Mann-Whitney test. In a blinded manner, the ∆ADC was compared to conventional MRI 3 weeks post-CRT and the routinely implemented CT, on average 3 months post-CRT, which used size-related and morphological criteria. Positive and negative predictive values (PPV and NPV, respectively) were compared between the ∆ADC and anatomical imaging. Results The ∆ADC of lesions with later tumor recurrence was significantly lower than lesions with complete remission for both primary lesions (−2.3% ± 0.3% vs. 80% ± 41%; p p = 0.003). The ∆ADC showed a PPV of 89% and an NPV of 100% for primary lesions and a PPV of 70% and an NPV of 96% for adenopathies per neck side. DWI improved PPV and NPV compared to anatomical imaging. Conclusion DWI with the ∆ADC 3 weeks after concluding CRT for HNSCC allows for early assessment of treatment response.

Purpose To evaluate the use of semi-quantitative dynamic contrast-enhanced MRI (DCE-MRI) parameters for the detection of prostatic carcinoma in correlation to whole-mount histopathology. Materials and methods Fifty-three patients with biopsy-proven prostate cancer were examined by DCE-MRI at 1.5-T. Cancerous and benign prostatic tissue regions of interest were delineated based on the histopathology of whole-mount sections and several semi-quantitative parameters were calculated: time to peak (TTP), maximal contrast enhancement (Cpeak), speed of contrast uptake (Wash-in) and clearance rate of the contrast agent (Wash-out). The area under the ROC curve was determined for each parameter. Results Within individual patients, a consistently higher Cpeak and faster Wash-in were present in cancerous compared to benign prostatic tissue. Both the TTP and the Wash-out occurred more rapidly in tumour tissue than in normal prostatic tissue. Despite a considerable inter-patient overlap of parameter values between tumour and normal prostatic tissue, area under the ROC curve analysis demonstrated that the Wash-in was a good discriminator for cancer and benign tissue (AUC 0.82). Combination of the Wash-in and the Wash-out proved to be even more accurate (AUC 0.87) to discriminate between cancerous and benign prostatic regions. Conclusion The Wash-in is a useful parameter for prostate cancer detection by DCE-MRI.

To compare a commercial contrast agent (CA) Dotarem and a necrosis-avid CA (NACA) for their ability to evaluate the therapeutic necrosis with a vascular disrupting agent (VDA) on magnetic resonance imaging in rodent liver tumors to determine which could better correlate with the histopathologic outcome.: After the VDA treatment, 16 rats with 32 liver rhabdomyosarcomas were randomized into Dotarem and NACA groups (n = 8 per group) for both interindividual and intraindividual comparisons. T2-weighted imaging, T1-weighted imaging (T1WI), contrast-enhanced T1-weighted imaging (CE-T1WI), and diffusion-weighted imaging were performed at baseline, after VDA treatment and CA injections. The enhancing efficacy of CAs at immediate and delayed enhancement on CE-T1WI in viable tumor and necrosis was compared. Tumor necrosis ratios calculated from NACA and Dotarem were compared and correlated with gold-standard histopathology.: On the immediate CE-T1WI, viable tumor was enhanced by either CA. On the delayed CE-T1WI at 30 minutes, both CAs failed to demarcate viable tumor from necrosis. At 24 hours post-NACA, the necrosis was clearly distinguished from viable tumor and thus derived necrosis ratio matched that from histopathology (P = 0.99); necrosis ratio from Dotarem was significantly lower than that from NACA and histopathology (P0.05, both), with a higher correlation of NACA than that of Dotarem with histopathology (r = 0.99 vs. r = 0.82).: NACA better evaluated VDA-induced tumor necrosis than nonspecific CA on T1WI in tumor models of rat liver. NACA showed a closer correlation with histopathology than nonspecific CA for the delineation of true necrosis. Delayed enhancement on T1WI with nonspecific CA is not suitable for the assessment of VDA-induced tumor necrosis.