Prediction of Mortality and Hepatic Encephalopathy after Transjugular Intrahepatic Portosystemic Shunt Placement: Baseline and Longitudinal Body Composition Measurement.

PURPOSE: To investigate effects of baseline and early longitudinal body composition changes on mortality and hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS). MATERIALS AND METHODS: This is a case-control study with analysis of a TIPS registry (1995-2020) including data from patients with cirrhosis with computed tomography (CT) scans obtained within 1 month before and 3 months after TIPS. Core muscle area (CMA), macroscopic subcutaneous adipose tissue (mSAT), macroscopic visceral adipose tissue (mVAT) area, and muscle adiposity index (MAI) on CT were obtained. Multipredictor Cox proportional hazards models were used to assess the effect of body composition variables on mortality or HE. RESULTS: In total, 280 patients (158 men; median age, 57.0 years; median Model for End-stage Liver Disease-sodium [MELD-Na] score, 14.0) were included. Thirty-four patients had post-TIPS imaging. Median baseline CMA was 68.3 cm2 (interquartile range, 57.7-83.5 cm2). Patients with higher baseline CMA had decreased risks of mortality (hazard ratio [HR]: 0.82; P = .04) and HE (HR: 0.82; P = .009). It improved prediction of mortality over MELD-Na and post-TIPS right atrial pressure alone (confidence interval = 0.729). An increase in CMA (HR: 0.60; P = .043) and mSAT (HR: 0.86; P = .022) or decrease in MAI (HR: 1.50; P = .049) from before to after TIPS was associated with a decreased risk of mortality. An increase in mSAT was associated with an increased risk of HE (HR: 1.11; P = .04). CONCLUSIONS: CMA on CT scan 1 month before TIPS placement predicts mortality and HE in patients with cirrhosis. Changes in body composition on CT measured 3 months after TIPS placement independently predict mortality and HE.

Changes in abdominal adipose tissue depots assessed by MRI correlate with hepatic histologic improvement in non-alcoholic steatohepatitis.

BACKGROUND & AIMS: Non-alcoholic steatohepatitis (NASH) is prevalent in adults with obesity and can progress to cirrhosis. In a secondary analysis of prospectively acquired data from the multicenter, randomized, placebo-controlled FLINT trial, we investigated the relationship between reduction in adipose tissue compartment volumes and hepatic histologic improvement. METHODS: Adult participants in the FLINT trial with paired liver biopsies and abdominal MRI exams at baseline and end-of-treatment (72 weeks) were included (n = 76). Adipose tissue compartment volumes were obtained using MRI. RESULTS: Treatment and placebo groups did not differ in baseline adipose tissue volumes, or in change in adipose tissue volumes longitudinally (p = 0.107 to 0.745). Deep subcutaneous adipose tissue (dSAT) and visceral adipose tissue volume reductions were associated with histologic improvement in NASH (i.e., NAS [non-alcoholic fatty liver disease activity score] reductions of ≥2 points, at least 1 point from lobular inflammation and hepatocellular ballooning, and no worsening of fibrosis) (p = 0.031, and 0.030, respectively). In a stepwise logistic regression procedure, which included demographics, treatment group, baseline histology, baseline and changes in adipose tissue volumes, MRI hepatic proton density fat fraction (PDFF), and serum aminotransferases as potential predictors, reductions in dSAT and PDFF were associated with histologic improvement in NASH (regression coefficient = -2.001 and -0.083, p = 0.044 and 0.033, respectively). CONCLUSIONS: In adults with NASH in the FLINT trial, those with greater longitudinal reductions in dSAT and potentially visceral adipose tissue volumes showed greater hepatic histologic improvements, independent of reductions in hepatic PDFF. CLINICAL TRIAL NUMBER: NCT01265498. IMPACT AND IMPLICATIONS: Although central obesity has been identified as a risk factor for obesity-related disorders including insulin resistance and cardiovascular disease, the role of central obesity in non-alcoholic steatohepatitis (NASH) warrants further clarification. Our results highlight that a reduction in central obesity, specifically deep subcutaneous adipose tissue and visceral adipose tissue, may be related to histologic improvement in NASH. The findings from this analysis should increase awareness of the importance of lifestyle intervention in NASH for clinical researchers and clinicians. Future studies and clinical practice may design interventions that assess the reduction of deep subcutaneous adipose tissue and visceral adipose tissue as outcome measures, rather than simply weight reduction.

Association between CT-based body composition assessment and patient outcomes during neoadjuvant chemotherapy for epithelial ovarian cancer.

OBJECTIVE: The aim of this study was to characterize the body composition of patients undergoing neoadjuvant chemotherapy (NACT) for epithelial ovarian cancer (EOC), identify factors associated with sarcopenia at diagnosis, and evaluate the impact of pretreatment sarcopenia and changes in body composition parameters during therapy on perioperative and disease-related outcomes. METHODS: Patients undergoing NACT for EOC between 2008 and 2020 were identified. Pre-treatment and post-treatment contrast-enhanced CT scans were reviewed to determine skeletal muscle index (SMI) and visceral adipose tissue (VAT) area at the mid-fourth lumbar vertebral level. SMI and VAT were analyzed for association with clinical and treatment variables. RESULTS: 174 patients were identified. Mean pretreatment SMI and VAT were 38.3 cm2/m2 ± 7.9 and 51.2 cm2/m2 ± 34.3, respectively. Comparatively, mean post-treatment SMI and VAT were 37.8 cm2/m2 ± 7.9 and 43.7 cm2/m2 ± 29.7, respectively. Most patients exhibited an overall decrease in SMI from pretreatment to posttreatment scans. Caucasian race, older age, and lower body mass index at diagnosis were associated with lower pretreatment SMI. Lower pre-treatment SMI was associated with lower surgical complexity scores (p < 0.001) and estimated blood loss (p = 0.029). Decrease in SMI after NACT was associated with increased rates of ICU admissions and length of stay. While there was no association between SMI and overall survival (OS) or progression-free survival (PFS), >2% decrease per 100 days in VAT was significantly associated with worse OS. CONCLUSIONS: Patients with lower pretreatment SMI tend to undergo less complex surgery than those with higher SMI despite NACT. Decrease in VAT may be a potential indicator of worse OS. Information on body composition can aid in clinical decision making in patients with EOC.

Disseminated Metacestode Versteria Species Infection in Woman, Pennsylvania, USA1.

A patient in Pennsylvania, USA, with common variable immunodeficiency sought care for fever, cough, and abdominal pain. Imaging revealed lesions involving multiple organs. Liver resection demonstrated necrotizing granulomas, recognizable tegument, and calcareous corpuscles indicative of an invasive cestode infection. Sequencing revealed 98% identity to a Versteria species of cestode found in mink.

Hepatic R2* is more strongly associated with proton density fat fraction than histologic liver iron scores in patients with nonalcoholic fatty liver disease.

BACKGROUND: The liver R2* value is widely used as a measure of liver iron but may be confounded by the presence of hepatic steatosis and other covariates. PURPOSE: To identify the most influential covariates for liver R2* values in patients with nonalcoholic fatty liver disease (NAFLD). STUDY TYPE: Retrospective analysis of prospectively acquired data. POPULATION: Baseline data from 204 subjects enrolled in NAFLD/NASH (nonalcoholic steatohepatitis) treatment trials. FIELD STRENGTH: 1.5T and 3T; chemical-shift encoded multiecho gradient echo. ASSESSMENT: Correlation between liver proton density fat fraction and R2*; assessment for demographic, metabolic, laboratory, MRI-derived, and histological covariates of liver R2*. STATISTICAL TESTS: Pearson's and Spearman's correlations; univariate analysis; gradient boosting machines (GBM) multivariable machine-learning method. RESULTS: Hepatic proton density fat fraction (PDFF) was the most strongly correlated covariate for R2* at both 1.5T (r = 0.652, P < 0.0001) and at 3T (r = 0.586, P < 0.0001). In the GBM analysis, hepatic PDFF was the most influential covariate for hepatic R2*, with relative influences (RIs) of 61.3% at 1.5T and 47.5% at 3T; less influential covariates had RIs of up to 11.5% at 1.5T and 16.7% at 3T. Nonhepatocellular iron was weakly associated with R2* at 3T only (RI 6.7%), and hepatocellular iron was not associated with R2* at either field strength. DATA CONCLUSION: Hepatic PDFF is the most influential covariate for R2* at both 1.5T and 3T; nonhepatocellular iron deposition is weakly associated with liver R2* at 3T only. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:1456-1466.

Do myocardial PET-MR and PET-CT FDG images provide comparable information?

INTRODUCTION: Although positron emission tomography PET-MR imaging is emerging into clinical practice, many aspects of this imaging technique such as attenuation correction have yet to be validated for myocardial imaging. Thus, it is uncertain whether PET-MR FDG images provide clinical information which is comparable to PET-CT FDG images. The study goal was to systematically compare relative myocardial FDG concentrations obtained from cardiac PET-MR images to those derived from same day PET-CT images. METHODS: Myocardial FDG images of 27 patients undergoing PET-CT imaging, followed by PET-MR imaging 42 ± 13 minutes later as part of a prospective oncology study were analyzed. Mean segmental standardized uptake measurements (SUVmean) were obtained in each of the 17 standard myocardial segments and normalized to the brightest segment. RESULTS: Normalized segmental SUVmean values did not differ significantly between the PET-MR and PET-CT images (mean difference 0.002, P = .826). The specific segment was a marginally significant predictor of the differences (P = .057), with the largest difference in the anteroseptal basal segment. CONCLUSIONS: PET-MR, vis-à-vis PET-CT, does not significantly raise segmental uptake relative to the brightest segment, suggesting that PET-MR can be used similarly to PET-CT for applications where relative uptake is important.

Hybrid PET/MR imaging: physics and technical considerations.

In just over a decade, hybrid imaging with FDG PET/CT has become a standard bearer in the management of cancer patients. An exquisitely sensitive whole-body imaging modality, it combines the ability to detect subtle biologic changes with FDG PET and the anatomic information offered by CT scans. With advances in MR technology and advent of novel targeted PET radiotracers, hybrid PET/MRI is an evolutionary technique that is poised to revolutionize hybrid imaging. It offers unparalleled spatial resolution and functional multi-parametric data combined with biologic information in the non-invasive detection and characterization of diseases, without the deleterious effects of ionizing radiation. This article reviews the basic principles of FDG PET and MR imaging, discusses the salient technical developments of hybrid PET/MR systems, and provides an introduction to FDG PET/MR image acquisition.

Practical guide for implementing hybrid PET/MR clinical service: lessons learned from our experience.

Positron emission tomography (PET) and magnetic resonance imaging, until recently, have been performed on separate PET and MR systems with varying temporal delay between the two acquisitions. The interpretation of these two separately acquired studies requires cognitive fusion by radiologists/nuclear medicine physicians or dedicated and challenging post-processing. Recent advances in hardware and software with introduction of hybrid PET/MR systems have made it possible to acquire the PET and MR images simultaneously or near simultaneously. This review article serves as a road-map for clinical implementation of hybrid PET/MR systems and briefly discusses hardware systems, the personnel needs, safety and quality issues, and reimbursement topics based on experience at NYU Langone Medical Center and Cleveland Clinic.

Tumor size is an independent predictor of lymph node metastasis and survival in early stage endometrioid endometrial cancer.

OBJECTIVE(S): To analyze the impact of tumor size (TS) on risk of lymph node metastasis (PLN) and prognosis in endometrioid endometrial cancer grossly confined to the uterus (EEC). METHOD(S): Patients with EEC grossly confined to the uterus were identified from Surveillance, Epidemiology, and End Results dataset from 1988 to 2007. Only surgically treated patients were included. TS was analyzed as a continuous and categorical variable (TS ≤ 2 cm, >2-5 cm and >5 cm). Multivariable logistic regression and Cox proportional hazards models were used. RESULT(S): 19,692 patients met the inclusion criteria. In patients with TS ≤ 2 cm, only 2.7 % (88/3,244) had PLN; this increased to 5.8 % (372/6,355) with TS > 2-5 cm and 11.1 % (195/1,745) with TS > 5 cm. The odds of PLN increased by 14 % for each 1 cm increase in TS after controlling for age, race, depth of myometrial invasion and grade (HR 1.14, 95 % CI 1.10-1.19, p < 0.001). Further, TS was an independent predictor of disease-specific survival (DSS) even after adjusting for age, race, grade, depth of myometrial invasion, lymph node status and adjuvant radiation therapy (HR 1.13 for each 1 cm increment in TS, 95 % 1.08-1.18, p < 0.001). In multivariable analysis, larger TS (>5 cm) was significantly associated with worse DSS (HR 2.09, 95 % 1.31-3.35, p = 0.002); however, there was no significant difference between TS > 2-5 cm versus ≤2 cm (HR 1.25, 95 % 0.85-1.83, p = 0.25). The impact of TS remained significant on DSS in subset of patients who underwent lymphadenectomy with negative lymph nodes. CONCLUSION(S): TS was an independent predictor of lymph node metastasis and disease-specific survival in patients with EEC grossly confined to the uterus. Tumor >5 cm was a predictor of disease-specific survival but no difference in outcome was noted between tumor >2-5 cm and tumor ≤2 cm.

Detection of urolithiasis: comparison of 100% tube exposure images reconstructed with filtered back projection and 50% tube exposure images reconstructed with sinogram-affirmed iterative reconstruction.

PURPOSE: To compare images acquired with 50% tube exposure with a dual-source computed tomographic (CT) scanner and reconstructed with sinogram-affirmed iterative reconstruction (SAFIRE) with 100% exposure images reconstructed with filtered back projection (FBP) for reader ability to detect stones, reader confidence, and findings outside the urinary tract. MATERIALS AND METHODS: In this HIPAA-compliant, institutional review board-approved study, imaging examinations in 99 patients with urolithiasis were assessed. Data from both tubes were reconstructed with FBP; data from the primary tube only were reconstructed with SAFIRE. Seven readers evaluated randomized studies for calculi in nine regions. Reader confidence was scored by using a five-point scale. Ancillary findings were noted. Nonparametric methods for clustered data were used to estimate the area under the receiver operating characteristic curves with 95% confidence intervals to test for noninferiority of 50% exposure with SAFIRE. RESULTS: Calculi were found in 113 locations (pyelocalyceal ureter, 86; proximal ureter, seven; midureter, four; distal ureter, 15; bladder, one) and not found in 752 locations. Mean area under the receiver operating characteristic curve for FBP was 0.879 (range, 0.607-0.967) and for SAFIRE, 0.883 (range, 0.646-0.971; 95% confidence interval: -0.025, 0.031). The SAFIRE images were not significantly inferior to FBP images (P = .001). Reader confidence levels for images with stones were similar with FBP and SAFIRE (P = .963). For the 52 patients who had extraurinary findings, readers reported them correctly in 74.4% (271 of 364) and 72.0% (262 of 364) of cases (P = .215) for FBP and SAFIRE, respectively. For the nine patients with potentially important findings per the reference standard, the detection rates were 44% (28 of 63) and 33% (21 of 63, P = .024), respectively. For the 43 patients with unimportant or likely unimportant findings, the false detection rates were 15% (44 of 301) and 14% (43 of 301, P = .756), respectively. CONCLUSION: The 50% tube exposure CT images reconstructed with SAFIRE were not inferior to 100% exposure images reconstructed with FBP for diagnosis of urolithiasis, without decreases in reader confidence.

Post-liver transplantation sarcopenia in cirrhosis: a prospective evaluation.

BACKGROUND AND AIM: Pre-transplant sarcopenia (reduced skeletal muscle mass) predicts poor outcome in cirrhosis. In contrast, whether muscle mass increases post-orthotopic liver transplantation (OLT) is not known and was studied prospectively. METHODS: Consecutive patients who underwent a comprehensive nutritional evaluation in a liver transplant nutrition clinic were included. Core abdominal muscle area was measured on abdominal computed tomography obtained pre- and post-OLT. Age- and gender-based controls were used to define sarcopenia. Measures of body composition pre-transplant were correlated with computed tomography measurements. Predictors and clinical impact of post-OLT change in muscle area were examined. In three subjects post-OLT and three controls, expression of genes regulating skeletal muscle mass were quantified. RESULTS: During the study period, 53 patients (M:F 41:12; age 56.9 ± 7.5 years) were followed up after OLT for 19.3 ± 9 months. Five patients died and another five had acute graft rejection. Pre-OLT sarcopenia was present in 33 (66.2%). Pre-transplant clinical characteristics including Child's score, MELD score, and nutritional status or post-transplantation immunosuppression regimen did not predict post-transplant change in muscle mass. New onset post-OLT sarcopenia developed in 14 patients. Loss of muscle mass post-OLT increased risk of diabetes mellitus and a trend toward higher mortality. Skeletal muscle expression of myostatin was higher and that of ubiquitin proteasome proteolytic components lower post-OLT than in controls. CONCLUSIONS: Post-transplantation sarcopenia is common and could not be attributed to pre-transplant characteristics or the type or duration of post-OLT immunosuppression. Post-transplant sarcopenia contributes to adverse consequences and strategies targeting myostatin may be beneficial.

Prospective comparison of positron emission tomography (PET)/magnetic resonance and PET/computed tomography dosimetry in hepatic malignant neoplastic disease after 90Y radioembolization treatment.

Background: 90Y radioembolization is an established treatment modality for hepatic malignancies. Successful radioembolization requires optimal dose delivery to tumors while minimizing dosages to parenchyma. Post-treatment positron emission tomography (PET)/computed tomography (CT) dosimetry is the established benchmark, whereas PET/magnetic resonance (MR) is an emerging modality. The goal of this study was to assess the intermodality agreement between PET/MR and PET/CT 90Y dosimetry. Methods: In this single-institution study, 18 patients (20 treatment sessions) with a primary or metastatic hepatic malignancy underwent both PET/MR and PET/CT after 90Y radioembolization. Patients were randomized to undergo one modality first, followed by the other. The region of interest was delineated using MR images and tumor and liver dosimetry was calculated. Intermodality agreement was assessed using the Bland-Altman method. A generalized linear model was used to assess the effect of baseline variables on intermodality dose differences. Results: PET/MR underestimated tumor and liver absorbed doses when compared to PET/CT by -3.7% (P=0.042) and -5.8% (P=0.029), respectively. A coverage probability plot demonstrated that 80% and 90% of tumor dose measurements fell within intermodality differences of 11% and 18%, respectively. PET/MR underestimated tumor dose at both low (<1 GBq) and high (>3 GBq) injected activity levels (P<0.001) by -22.3 [standard deviation (SD) =13.5] and -24.3 (SD =18.7), respectively. Conclusions: Although PET/MR significantly underestimated the absorbed dose when compared to PET/CT, the intermodality agreement was high and the degree of underestimation was better than previously reported. Intermodality differences were more pronounced at low and high injected doses. Additional studies are required to assess the clinical implications of these findings.

Gastrointestinal malignancies in pregnancy.

Gastrointestinal malignancies, though uncommon in pregnancy, present several unique challenges with regards to diagnosis, staging, and treatment. Imaging the pregnant patient with a suspected or confirmed GI malignancy requires modifications to the radiologic modality of choice and protocol in order to minimize harm to the fetus, ensure accuracy in diagnosis and staging and guide treatment decisions. In this review article, we discuss the imaging approach to the pregnant patient with GI cancer, including safe radiologic modalities and modifications to imaging protocols. We also review the most common GI cancers encountered in pregnancy, including colorectal, pancreatic, gastric, and small bowel tumors, with emphasis to imaging findings, staging, and treatment considerations.

Bosniak category IIF and III cystic renal lesions: outcomes and associations.

PURPOSE: To evaluate clinical outcomes, pathologic subtypes, metastatic disease rate, and clinical features associated with malignancy in Bosniak category IIF and III cystic renal lesions. MATERIALS AND METHODS: This retrospective study was institutional review board approved and HIPAA compliant. Informed consent was waived. Radiology and hospital information systems were searched for Bosniak IIF and Bosniak III lesions in computed tomographic (CT) reports from January 1, 1994 to August 31, 2009. Patients 18 years and older with unenhanced and contrast material-enhanced CT results and with lesions either surgically resected or with 1 year or more of surveillance were included. Data recorded were history of renal cell carcinoma, number of renal lesions, presence of a coexistent solid renal mass, surgical pathologic findings, and presence of metastatic disease from a renal malignancy. Sixty-two patients with 69 Bosniak IIF lesions and 131 patients with 144 Bosniak III lesions were identified. Proportions from independent groups were compared by using the Fisher exact test; continuous variables were compared by using a two-tailed two-sample t test or a Wilcoxon two-sample test. RESULTS: The malignancy rate of resected Bosniak IIF lesions was 25% (four of 16) and that for Bosniak III lesions was 54% (58 of 107) (P = .03). Thirteen percent (nine of 69) of Bosniak IIF lesions progressed at follow-up, and 50% (four of eight) of these resected cysts were malignant. History of primary renal malignancy, coexisting Bosniak category IV lesion and/or solid renal mass, and multiplicity of Bosniak III lesions were each associated with an increased malignancy rate in Bosniak III lesions. No patients developed locally advanced or metastatic disease from a Bosniak IIF or III lesion. CONCLUSION: Although the malignancy rate in surgically excised Bosniak IIF and Bosniak III cystic renal lesions was 25% and 54%, respectively, in our study, the malignancy rate was higher in patients with a history of primary renal malignancy or coexisting Bosniak IV lesion and/or solid renal neoplasm.

Adrenal imaging: a primer for oncosurgeons.

Differentiation of an incidental adrenal lesion into benign and malignant etiologies is an endeavor with significant and obvious clinical benefit. Advances in imaging now enable this differentiation in high proportion of patients in a non-invasive manner. The ACR guidelines elaborated in this review seek to promote clinically meaningful, evidence-based approach to an IAL. Knowledge of the potential as well the limitations of individual modalities is essential so as to streamline investigations in a cost-effective manner.

Orthotopic liver transplantation: reversible Doppler US findings in the immediate postoperative period.

Orthotopic liver transplantation (OLT) is the only definitive treatment for irreversible acute liver failure and chronic liver disease. In the immediate postoperative period after OLT, patients are closely monitored with Doppler ultrasonography (US) to detect treatable vascular complications and ensure graft survival. The first postoperative Doppler US examination is performed fairly early on the first postoperative day, before surgical wound closure has been performed. The immediate postoperative images, obtained when the effects of surgery are very recent, often reveal an array of findings that may appear alarming but that tend to normalize within a few days and are compatible with changes related to the surgery itself. These findings include a starry-sky appearance of reperfusion hepatic edema, transient foci of increased echogenicity, pneumobilia, small fluid collections, perihepatic hematomas, pleural effusion, temporary elevation of hepatic arterial velocity, transient elevation of resistive index (RI), decreased RI with tardus parvus waveform, increased portal venous flow and mono- or biphasic waveforms of the hepatic veins. Most of these changes revert to normal in the first postoperative week; deterioration atypical of transient changes requires further evaluation.

Hepatocellular adenomas: current update on genetics, taxonomy, and management.

Hepatocellular adenomas (HCAs) are uncommon, benign hepatocellular neoplasms that commonly occur in young women. Recent advances in pathology and cytogenetics have thrown fresh light on the pathogenesis of HCAs leading to classification of HCAs into 3 distinct subtypes, each with a characteristic epidemiology, histopathology, oncogenesis, and imaging findings. The aim of the article was to provide a comprehensive review of contemporary taxonomy of HCAs, with an emphasis on cross-sectional imaging findings and management.

Assessing tumor response and detecting recurrence in metastatic renal cell carcinoma on targeted therapy: importance of size and attenuation on contrast-enhanced CT.

OBJECTIVE: The aim of this study was to improve response assessment in patients with metastatic renal cell carcinoma (RCC) on antiangiogenic targeted therapy by evaluating changes in both tumor size and attenuation and by detecting unique patterns of contrast enhancement on contrast-enhanced CT (CECT). MATERIALS AND METHODS: Tumor long-axis measurements and volumetric mean tumor attenuation of target lesions on CECT images were correlated with time to progression in 53 patients with metastatic clear cell RCC treated with first-line sorafenib or sunitinib. The frequencies of specific patterns of tumor progression were assessed. The data were used to develop new imaging criteria, the size and attenuation CT (SACT) criteria. CECT findings were evaluated using the SACT criteria, Response Evaluation Criteria in Solid Tumors (RECIST), and modified Choi criteria, and the Kaplan-Meier method was used to estimate survival functions. RESULTS: One or more target metastatic lesions had decreased attenuation of >or=40 HU in 59% of patients with progression-free survival of >250 days (n=44) after initiating targeted therapy; 0% of patients with earlier disease progression (n=9) had this finding. A favorable response based on SACT criteria had a sensitivity of 75% and specificity of 100% for identifying patients with progression-free survival of >250 days, versus 16% and 100%, respectively, for RECIST and 93% and 44% for the modified Choi criteria. CONCLUSION: Objectively measuring changes in both tumor size and attenuation on the first CECT study after initiating targeted therapy for metastatic RCC markedly improves response assessment. Distinct patterns of disease recurrence are seen in patients with metastatic RCC on targeted therapy.

Morphology, Attenuation, Size, and Structure (MASS) criteria: assessing response and predicting clinical outcome in metastatic renal cell carcinoma on antiangiogenic targeted therapy.

OBJECTIVE: The objective of our study was to evaluate response assessment and predict clinical outcome in patients with metastatic renal cell carcinoma (RCC) receiving antiangiogenic targeted therapy. Target lesions were assessed on routine contrast-enhanced CT (CECT) images obtained during the portal venous phase using new response criteria. MATERIALS AND METHODS: Standard CECT examinations of patients with metastatic clear cell RCC on first-line sunitinib or sorafenib therapy (n = 84) were retrospectively evaluated using Mass, Attenuation, Size, and Structure (MASS) Criteria; Response Evaluation Criteria in Solid Tumors (RECIST); Size and Attenuation CT (SACT) Criteria; and modified Choi Criteria. The objective response to therapy was compared with clinical outcomes including time to progression (TTP) and disease-specific survival. The Kaplan-Meier method was used to estimate survival functions. RESULTS: A favorable response according to MASS Criteria had a sensitivity of 86% and specificity of 100% in identifying patients with a good clinical outcome (i.e., progression-free survival of > 250 days) versus 17% and 100%, respectively, for RECIST partial response. The objective categories of response used by MASS Criteria-favorable response, indeterminate response, and unfavorable response-differed significantly from one another with respect to TTP (p < 0.0001, log-rank test) and disease-specific survival (p < 0.0001, log-rank test). CONCLUSION: Assessment of metastatic RCC target lesions on CECT for changes in morphology, attenuation, size, and structure by MASS Criteria is more accurate than response assessment by SACT Criteria, RECIST, or modified Choi Criteria. Furthermore, the use of MASS Criteria for imaging response assessment showed high interobserver agreement and may predict disease outcome in patients with metastatic RCC on targeted therapy.

Role of imaging in the management of splenic artery steal syndrome.

OBJECTIVE: The purpose of this study is to discuss the etiology and role of imaging in the management of splenic artery steal syndrome (SASS) following orthotropic liver transplantation (OLT). METHODS: Hepatic arterial thrombosis and stenosis have been the most commonly recognized arterial complications following OLT. Splenic artery steal syndrome is a recently described entity in the transplant literature and thought to be an under-recognized cause of graft ischemia. It is characterized by hepatic arterial hypoperfusion accompanied by splenic arterial and portal venous hyperperfusion and leads to various vascular and biliary graft complications. Because the clinical manifestations of SASS are so non-specific, imaging plays a key role in the diagnosis of this condition. RESULTS: This article discusses the role of imaging in the management of this potentially reversible cause of graft ischemia. CONCLUSIONS: Awareness of the imaging features and having a high index of suspicion are essential for the early diagnosis and prompt management of this condition.