Magnetic resonance imaging-based risk factors of hepatocellular carcinoma after direct-acting antiviral therapy: A multicenter observational study.

AIM: To determine risk factors associated with hepatocellular carcinoma (HCC) development following direct-acting antiviral (DAA) therapy. METHODS: We enrolled patients with chronic hepatitis C who underwent direct-acting antiviral therapy and achieved sustained virologic response at 12 weeks between 2012 and 2018. Subsequently, patients were followed up. The primary endpoint was the development of HCC or the date of the last follow up when the absence of HCC was confirmed. Uni- and multivariate Cox proportional hazards models were used to identify factors contributing to HCC development, including gadoxetic acid-enhanced magnetic resonance imaging findings. The cumulative incidence rates of HCC development were calculated using the Kaplan-Meier method, and differences between groups were assessed using the log-rank test. RESULTS: The final study cohort comprised 482 patients (median age 70.5 years; 242 men). The median follow-up period was 36.8 months. Among 482 patients, 96 developed HCC (19.9%). The 1-, 3-, and 5-year cumulative rates of HCC development were 4.9%, 18.6%, and 30.5%, respectively. Multivariate analysis revealed that age, male sex, history of HCC, and hepatobiliary phase hypointense nodules without arterial phase hyperenhancement were independent risk factors significantly associated with HCC development (p < 0.001-0.04). The highest risk group included patients with both a history of HCC and the presence of hepatobiliary phase hypointense nodules without arterial phase hyperenhancement (the 1- and 3-year cumulative HCC development rates were 14.2% and 62.2%, respectively). CONCLUSION: History of HCC and presence of hepatobiliary phase hypointense nodules without arterial phase hyperenhancement were strong risk factors for HCC development following direct-acting antiviral therapy.

Association between tumor morphology and efficacy of atezolizumab plus bevacizumab for advanced hepatocellular carcinoma.

AIM: The IMbrave150 trial revealed that atezolizumab plus bevacizumab (AtezoBv) showed a higher objective response rate (ORR) in patients with advanced hepatocellular carcinoma (HCC). Although conversion therapy after AtezoBv has been recently reported, markers predictive of its efficacy, particularly radiological imaging markers, have not yet been identified. The present study focused on tumor morphological appearance on radiological imaging and evaluated whether it could be associated with AtezoBv efficacy. METHODS: Ninety-five intrahepatic lesions in 74 patients who were given AtezoBv for advanced HCC were recruited for evaluation. The lesions were divided into two groups, simple nodular (SN group) and non-simple nodular (non-SN group), based on the gross morphology on pretreatment imaging, and retrospectively evaluated for treatment response and other relevant clinical outcomes. RESULTS: Assessing the size of individual tumors after treatment, waterfall plots showed that tumor shrinkage in the non-SN group including 56 lesions was higher than that in the SN group comprising 39 lesions. The ORR was significantly higher in the non-SN group (39.3% vs. 15.4%, p = 0.012). Additionally, the median time to nodular progression was longer in the non-SN group (21.0 months vs. 8.1 months, p = 0.119) compared to the SN group. Six patients with non-SN lesions underwent sequential local therapy. CONCLUSIONS: Atezolizumab plus bevacizumab may show increased therapeutic efficacy in patients with tumors with a higher potential for aggressive oncological behavior, such as non-SN lesions. Treatment strategies focusing on conversion therapy may be crucial in patients with non-SN lesions.

A Novel Method Using Gadolinium-Ethoxybenzyl Diethylenetriamine Pentaacetate Acid-Enhanced Magnetic Resonance Imaging for Predicting Post-Hepatectomy Liver Failure in Hepatocellular Carcinoma Patients with a Major Portal Vein Tumor Thrombus.

INTRODUCTION: The usefulness of gadolinium-ethoxybenzyl diethylenetriamine pentaacetate acid-enhanced magnetic resonance imaging (EOB-MRI) in assessing the functional future remnant liver volume (fFRLV) to predict post-hepatectomy liver failure (PHLF) has been previously reported. Herein, we evaluated the efficacy of this technique in patients with hepatocellular carcinoma (HCC) with a major portal vein tumor thrombus (PVTT). METHODS: This study included 21 patients with PVTT in the ipsilateral first-order branch (Vp3) and 30 patients with PVTT in the main trunk/contralateral branch (Vp4). To evaluate fFRLV, the signal intensity (SI) of the remnant liver was determined on T1-weighted images, using both conventional and newly developed methods. The fFRLV was calculated using the SI of the remnant liver and muscle, remnant liver volume, and body surface area. Preoperative factors predicting PHLF (≥grade B) in HCC patients with Vp3/4 PVTT were evaluated. RESULTS: In the Vp3 group, we found fFRLV area under the receiver-operating characteristic curves (AUCs) above 0.70 (AUC = 0.875, 0.750) using EOB-MRI results calculated using either the plot or whole method. None of the parameters in the Vp4 group had an AUC greater than 0.70. CONCLUSION: The fFRLV calculated by EOB-MRI using the whole method can be as useful as the conventional method in predicting PHLF (≥grade B) for HCC patients with Vp3 PVTT.

The Usefulness of Total Tumor Volume as a Prognostic Factor and in Selecting the Optimal Treatment Strategy of Chemotherapeutic Intervention in Patients with Colorectal Liver Metastases.

BACKGROUND: Few reports have discussed the association between total tumor volume (TTV) and prognosis in patients with colorectal liver metastases (CRLM). The present study aimed to evaluate the usefulness of TTV for predicting recurrence-free survival and overall survival (OS) in patients receiving initial hepatic resection or chemotherapy, and to investigate the value of TTV as an indicator for optimal treatment selection for patients with CRLM. PATIENTS AND METHODS: This retrospective cohort study included patients with CRLM who underwent hepatic resection (n = 93) or chemotherapy (n = 78) at the Kobe University Hospital. TTV was measured using 3D construction software and computed tomography images. RESULTS: A TTV of 100 cm3 has been previously reported as a significant cut-off value for predicting OS of CRLM patients receiving initial hepatic resection. For patients receiving hepatic resection, the OS for those with a TTV ≥ 100 cm3 was significantly reduced compared with those with a TTV < 100 cm3. For patients receiving initial chemotherapy, there were no significant differences between the groups divided according to TTV cut-offs. Regarding OS of patients with TTV ≥ 100 cm3, there was no significant difference between hepatic resection and chemotherapy (p = 0.160). CONCLUSIONS: TTV can be a predictive factor of OS for hepatic resection, unlike for initial chemotherapy treatment. The lack of significant difference in OS for CRLM patients with TTV ≥ 100 cm3, regardless of initial treatment, suggests that chemotherapeutic intervention preceding hepatic resection may be indicated for such patients.

Association of Sarcopenia with a Poor Prognosis and Decreased Tumor-Infiltrating CD8-Positive T Cells in Pancreatic Ductal Adenocarcinoma: A Retrospective Analysis.

BACKGROUND: Sarcopenia, defined as a loss of skeletal muscle mass and quality, is found in 30-65% of patients with pancreatic ductal adenocarcinoma (PDAC) at diagnosis, and is a poor prognostic factor. However, it is yet to be evaluated why sarcopenia is associated with poor prognosis. Therefore, this study elucidated the tumor characteristics of PDAC with sarcopenia, including driver gene alterations and tumor microenvironment. PATIENTS AND METHODS: We retrospectively analyzed 162 patients with PDAC who underwent pancreatic surgery between 2008 and 2017. We defined sarcopenia by measuring the skeletal muscle mass at the L3 level using preoperative computed tomography images and evaluated driver gene alteration (KRAS, TP53, CDKN2A/p16, and SMAD4) and tumor immune (CD4+, CD8+, and FOXP3+) and fibrosis status (stromal collagen). RESULTS: In localized-stage PDAC (stage ≤ IIa), overall survival (OS) and recurrence-free survival were significantly shorter in the sarcopenia group than in the non-sarcopenia group (2-year OS 89.7% versus 59.1%, P = 0.03; 2-year RFS 74.9% versus 50.0%, P = 0.02). Multivariate analysis revealed that sarcopenia was an independent poor prognostic factor in localized-stage PDAC. Additionally, tumor-infiltrating CD8+ T cells in the sarcopenia group were significantly less than in the non-sarcopenia group (P = 0.02). However, no difference was observed in driver gene alteration and fib.rotic status. These findings were not observed in advanced-stage PDAC (stage ≥ IIb). CONCLUSIONS: Sarcopenia was associated with a worse prognosis and decreased tumor-infiltrating CD8+ T cells in localized-stage PDAC. Sarcopenia may worsen a patient's prognosis by suppressing local tumor immunity.

Deep learning image reconstruction to improve accuracy of iodine quantification and image quality in dual-energy CT of the abdomen: a phantom and clinical study.

OBJECTIVES: To investigate the effect of deep learning image reconstruction (DLIR) on the accuracy of iodine quantification and image quality of dual-energy CT (DECT) compared to that of other reconstruction algorithms in a phantom experiment and an abdominal clinical study. METHODS: An elliptical phantom with five different iodine concentrations (1-12 mgI/mL) was imaged five times with fast-kilovoltage-switching DECT for three target volume CT dose indexes. All images were reconstructed using filtered back-projection, iterative reconstruction (two levels), and DLIR algorithms. Measured and nominal iodine concentrations were compared among the algorithms. Contrast-enhanced CT of the abdomen with the same scanner was acquired in clinical patients. In arterial and portal venous phase images, iodine concentration, image noise, and coefficients of variation for four locations were retrospectively compared among the algorithms. One-way repeated-measures analyses of variance were used to evaluate differences in the iodine concentrations, standard deviations, coefficients of variation, and percentages of error among the algorithms. RESULTS: In the phantom study, the measured iodine concentrations were equivalent among the algorithms: within ± 8% of the nominal values, with root-mean-square deviations of 0.08-0.36 mgI/mL, regardless of radiation dose. In the clinical study (50 patients; 35 men; mean age, 68 ± 11 years), iodine concentrations were equivalent among the algorithms for each location (all p > .99). Image noise and coefficients of variation were lower with DLIR than with the other algorithms (all p < .01). CONCLUSIONS: The DLIR algorithm reduced image noise and variability of iodine concentration values compared with other reconstruction algorithms in the fast-kilovoltage-switching dual-energy CT. KEY POINTS: • In the phantom study, standard deviations and coefficients of variation in iodine quantification were lower on images with the deep learning image reconstruction algorithm than on those with other algorithms. • In the clinical study, iodine concentrations of measurement location in the upper abdomen were consistent across four reconstruction algorithms, while image noise and variability of iodine concentrations were lower on images with the deep learning image reconstruction algorithm.

Lenvatinib Mitigates Transarterial Embolization-Induced Polarization of Tumor-Associated Macrophages in a Rat Hepatocellular Carcinoma Model.

PURPOSE: To investigate the effect of transarterial embolization (TAE) on macrophage polarization and the modulatory effect of lenvatinib when used in combination with TAE in a rat hepatocellular carcinoma model. MATERIALS AND METHODS: A N1S1-bearing orthotopic rat model was subjected to TAE and administered 5 mg/kg of lenvatinib. CD8+, CD68+, and CD206+ cells were examined in 4 groups: sham (n = 5), lenvatinib (n = 5), TAE (n = 5), and combination of TAE and lenvatinib (n = 5). Transcriptome analysis was performed to assess gene expression related to macrophage polarization in the sham, TAE, and combination groups. An in vitro coculture experiment with bone marrow-derived macrophages was performed to identify lenvatinib target in macrophage polarization. RESULTS: There were no significant differences in the number of CD8+ and CD68+ cells among the 4 groups. Tumor-associated macrophage positivity for CD206 was significantly higher in the TAE group (58.1 ± 20.9) than in the sham (11.2 ± 14.3; P < .001) and combination (27.1 ± 19.7; P = .003) groups. In the transcriptome analysis, compared with the genes in the sham group, 5 macrophage polarization-related genes, including St6gal1, were upregulated by more than 1.5 fold in the TAE group and downregulated by more than 1.5 fold in the combination group. The coculture experiment showed that lenvatinib did not affect macrophages but affected N1S1 cells, leading to macrophage polarization. CONCLUSIONS: TAE-induced M2 macrophage polarization. Lenvatinib administration with TAE could reprogram macrophage polarization, improving tumor immune microenvironment.

Lobularity rather than hyperechoic foci/stranding on endoscopic ultrasonography is associated with more severe histological features in chronic pancreatitis.

BACKGROUND AND AIM: Endoscopic ultrasonography (EUS) findings of the pancreatic parenchyma, such as hyperechoic foci/stranding and lobularity, may be associated with the severity of chronic pancreatitis (CP). However, the correlation between parenchymal EUS findings and histology remains unclear. We designed a large-scale retrospective study analyzing over 200 surgical specimens to elucidate the association between parenchymal EUS findings and histological features. METHODS: Clinical data of 221 patients with pancreatobiliary tumors who underwent preoperative EUS and pancreatic surgery between January 2010 and November 2020 were reviewed to investigate the association between parenchymal EUS findings and histological features at the pancreatic body. None of these patients met the definition of CP. RESULTS: Of the 221 patients, 87 (39.4%), 89 (40.2%), and 45 (20.4%) had normal EUS findings, hyperechoic foci/stranding without lobularity, and hyperechoic foci/stranding with lobularity, respectively. In the multivariate analyses, parenchymal EUS findings significantly correlated with histological CP findings of fibrosis, inflammation, and atrophy (hyperechoic foci/stranding without lobularity vs hyperechoic foci/stranding with lobularity, odds ratio [95% confidence interval]: 4.1 [2.2-7.9] vs 31.3 [9.3-105.6], Ptrend  < 0.001; 3.9 [1.9-8.2] vs 21.8 [8.0-59.4], Ptrend  < 0.001; and 4.0 [2.0-7.8] vs 22.9 [7.0-74.5], Ptrend  < 0.001, respectively). Further, a trend toward higher histological grade was observed in the following order: normal findings, hyperechoic foci/stranding without lobularity, and hyperechoic foci/stranding with lobularity. CONCLUSIONS: Endoscopic ultrasonography findings of the pancreatic parenchyma may be associated with the histological conditions in CP, such as pancreatic fibrosis, inflammation, and atrophy. Lobularity reflects more severe histological conditions than does hyperechoic foci/stranding.

Transarterial chemoembolization for liver metastases of a pancreatic neuroendocrine neoplasm: a single-center experience.

Transarterial chemoembolization (TACE) is performed for pancreatic neuroendocrine tumor (PanNEN) liver metastases; however, the safety and efficacy of TACE procedures, especially for patients who have undergone previous pancreatic surgery, have not been established. We reviewed 48 TACE procedures (1-6 procedures/patient) performed on 11 patients with PanNEN liver metastases, including 16 TACE procedures (4-6 procedures/patient) for 3 patients with a history of biliary-enteric anastomosis. The overall tumor objective response rate was 94%. The incidence of Clavien‒Dindo grade ≥ 2 complications was 1/16 (6%) and 1/32 (3%), and the median time to untreatable progression was 31 (14-41) and 27 (2-60) months among patients with and without a history of biliary-enteric anastomosis, respectively. Although validation is needed in future studies, our experiences have shown that TACE treatment is a viable treatment option for PanNEN liver metastases, even after biliary-enteric anastomosis with experienced teams and careful patient follow-up.

Comprehensive Analysis of Molecular Biologic Characteristics of Pancreatic Ductal Adenocarcinoma Concomitant with Intraductal Papillary Mucinous Neoplasm.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) concomitant with intraductal papillary mucinous neoplasm (IPMN) is defined as PDAC occurring apart from IPMN. This study comprehensively investigated the molecular biologic characteristics of PDAC concomitant with IPMN in major genetic alterations, tumor microenvironment, and prognosis by contrast with those of conventional PDAC. METHODS: The study retrospectively reviewed the data of 158 surgically resected PDAC patients. The driver gene alteration status (KRAS, TP53, CDKN2A, SMAD4, and GNAS) together with the immune and fibrotic status in tumor was evaluated. The prognosis of PDAC concomitant with IPMN and that of conventional PDAC also were compared. RESULTS: No statistically significant difference was found between PDAC concomitant with IPMN and conventional PDAC in the alteration frequency analysis of the major driver genes and the immune and fibrotic status in the tumor microenvironment. Overall survival and disease-free survival between patients who had PDAC concomitant with IPMN and those who had conventional PDAC did not show statistically significant differences in propensity-matched subjects. Furthermore, the co-existence of IPMN was not a poor prognostic factor in the multivariable-adjusted Cox proportional hazards model (hazard ratio, 0.95; 95 % confidence interval, 0.51-1.78). CONCLUSIONS: In this study, PDAC concomitant with IPMN had tumor characteristics similar to those of conventional PDAC in terms of the major driver gene alterations, tumor microenvironment, and prognosis.

Abbreviated Gadoxetic Acid-Enhanced MRI for the Detection of Liver Metastases in Patients With Potentially Resectable Pancreatic Ductal Adenocarcinoma.

BACKGROUND: Gadoxetic acid-enhanced magnetic resonance imaging (MRI) is useful in detecting liver metastases from pancreatic ductal adenocarcinoma (PDAC). However, the long examination time limits its utility in the initial workup of patients with PDAC. PURPOSE: To evaluate the incremental value of an abbreviated gadoxetic acid-enhanced MRI for the detection of liver metastases in patients with PDAC. STUDY TYPE: Retrospective. POPULATION: Patients (N = 130) with potentially resectable PDAC (women, 58 [44.6%]). FIELD STRENGTH/SEQUENCE: 1.5 T and 3 T; gradient dual-echo T1-weighted (in-phase and opposed-phase), fat-suppressed fast spin-echo T2-weighted, single-shot echo-planar diffusion-weighted, and three-dimensional fat-suppressed T1-weighted gradient-echo dynamic contrast-enhanced and hepatobiliary phase sequences, as well as contrast-enhanced computed tomography (CECT). ASSESSMENT: Three radiologists independently reviewed three different image sets to detect liver metastases: set 1, CECT alone; set 2, CECT and abbreviated MRI comprising fat-suppressed T2-weighted, diffusion-weighted, and hepatobiliary phase images; and set 3, CECT and standard gadoxetic acid-enhanced MRI. STATISTICAL TESTS: Figure of merit (FOM) was compared using the jackknife alternative free-response receiver operating characteristics, and other per-lesion and per-patient diagnostic parameters for each image set were compared using McNemar's and Fisher's test. P < 0.05 was considered statistically significant. RESULTS: A total of 43 liver metastases were identified in 13 patients. Reader-averaged FOM to detect liver metastases were significantly higher for sets 2 (0.884) and 3 (0.886) than for set 1 (0.609), while they were comparable between sets 2 and 3 (P = 0.96). The mean per-patient sensitivities, negative predictive values, and accuracies were significantly higher for sets 2 and 3 than for set 1, while those between sets 2 and 3 were not significantly different (not applicable, P > 0.99, and P > 0.99, respectively). DATA CONCLUSION: Gadoxetic acid-enhanced MRI combined with CECT had higher diagnostic performance than CECT alone for the detection of liver metastases in patients with PDAC. The incremental values were comparable for the abbreviated MRI and standard MRI. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Estimation of pancreatic fibrosis and prediction of postoperative pancreatic fistula using extracellular volume fraction in multiphasic contrast-enhanced CT.

OBJECTIVE: To investigate the diagnostic performance of the extracellular volume (ECV) fraction in multiphasic contrast-enhanced computed tomography (CE-CT) for estimating histologic pancreatic fibrosis and predicting postoperative pancreatic fistula (POPF). METHODS: Eighty-five patients (49 men; mean age, 69 years) who underwent multiphasic CE-CT followed by pancreaticoduodenectomy with pancreaticojejunal anastomosis between January 2012 and December 2018 were retrospectively included. The ECV fraction was calculated from absolute enhancements of the pancreas and aorta between the precontrast and equilibrium-phase images, followed by comparisons among histologic pancreatic fibrosis grades (F0‒F3). The diagnostic performance of the ECV fraction in advanced fibrosis (F2‒F3) was evaluated using receiver operating characteristic curve analysis. Multivariate logistic regression analysis was used to evaluate the associations of the risk of POPF development with patient characteristics, histologic findings, and CT imaging parameters. RESULTS: The mean ECV fraction of the pancreas was 34.4% ± 9.5, with an excellent intrareader agreement of 0.811 and a moderate positive correlation with pancreatic fibrosis (r = 0.476; p < 0.001). The mean ECV fraction in advanced fibrosis was significantly higher than that in no/mild fibrosis (44.4% ± 10.8 vs. 31.7% ± 6.7; p < 0.001), and the area under the receiver operating characteristic curve for the diagnosis of advanced fibrosis was 0.837. Twenty-two patients (25.9%) developed clinically relevant POPF. Multivariate logistic regression analysis demonstrated that the ECV fraction was a significant predictor of POPF. CONCLUSIONS: The ECV fraction can offer quantitative information for assessing pancreatic fibrosis and POPF after pancreaticojejunal anastomosis. KEY POINTS: • There was a moderate positive correlation of the extracellular volume (ECV) fraction of the pancreas in contrast-enhanced CT with the histologic grade of pancreatic fibrosis (r = 0.476; p < 0.001). • The ECV fraction was higher in advanced fibrosis (F2‒F3) than in no/mild fibrosis (F0‒F1) (p < 0.001), with an AUC of 0.837 for detecting advanced fibrosis. • The ECV fraction was an independent risk factor for predicting subclinical (odds ratio, 0.81) and clinical (odds ratio, 0.80) postoperative pancreatic fistula.

Acute pancreatitis in intraductal papillary mucinous neoplasms correlates with pancreatic volume and epithelial subtypes.

BACKGROUND: Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is associated with acute pancreatitis (AP) in some cases, however its causes have not been fully elucidated. We investigated the association of the incidence of AP with epithelial subtypes and pancreatic volume in IPMN. METHODS: This retrospective study included 182 consecutive surgically resected IPMN patients between January 2000 and December 2018. The relationship between the incidence of AP and epithelial subtypes of IPMN and pancreatic volume was investigated. Epithelial subtypes of IPMN were classified into gastric (G type: N = 116), intestinal (I type: N = 49), pancreatobiliary (PB type: N = 14), and oncocytic types (O type: N = 3). Pancreatic volume of the contrast-enhanced computed tomography scan was measured using Ziostation2 software. Histological pancreatic parenchymal atrophy was also evaluated. RESULTS: AP occurred more frequently in I-types (I-type vs. G-type, 22.4% [11/49] vs 3.4% [4/116], P = 0.003) and PB-types (PB type vs. G-type, 35.7% [5/14] vs. 3.4% [4/116], P = 0.007) in comparison with G-types, which constituted the majority of the resected IPMNs. AP occurred more frequently in I-type patients with high pancreatic volumes (I-type with high pancreatic volume vs. I-type with low pancreatic volume, 37.0% [10/27] vs. 4.7% [1/21], P = 0.02). However, histological atrophy did not show an additional influence on the association between the incidence of AP and epithelial subtypes. The elevation of serum pancreatic enzymes was not significantly related to epithelial subtypes. CONCLUSION: Epithelial subtypes and the degree of pancreatic volume may be closely associated with the incidence of AP in IPMN.

Deep learning model for predicting gestational age after the first trimester using fetal MRI.

OBJECTIVES: To evaluate a deep learning model for predicting gestational age from fetal brain MRI acquired after the first trimester in comparison to biparietal diameter (BPD). MATERIALS AND METHODS: Our Institutional Review Board approved this retrospective study, and a total of 184 T2-weighted MRI acquisitions from 184 fetuses (mean gestational age: 29.4 weeks) who underwent MRI between January 2014 and June 2019 were included. The reference standard gestational age was based on the last menstruation and ultrasonography measurements in the first trimester. The deep learning model was trained with T2-weighted images from 126 training cases and 29 validation cases. The remaining 29 cases were used as test data, with fetal age estimated by both the model and BPD measurement. The relationship between the estimated gestational age and the reference standard was evaluated with Lin's concordance correlation coefficient (ρc) and a Bland-Altman plot. The ρc was assessed with McBride's definition. RESULTS: The ρc of the model prediction was substantial (ρc = 0.964), but the ρc of the BPD prediction was moderate (ρc = 0.920). Both the model and BPD predictions had greater differences from the reference standard at increasing gestational age. However, the upper limit of the model's prediction (2.45 weeks) was significantly shorter than that of BPD (5.62 weeks). CONCLUSIONS: Deep learning can accurately predict gestational age from fetal brain MR acquired after the first trimester. KEY POINTS: • The prediction of gestational age using ultrasound is accurate in the first trimester but becomes inaccurate as gestational age increases. • Deep learning can accurately predict gestational age from fetal brain MRI acquired in the second and third trimester. • Prediction of gestational age by deep learning may have benefits for prenatal care in pregnancies that are underserved during the first trimester.

VI-RADS: Multiinstitutional Multireader Diagnostic Accuracy and Interobserver Agreement Study.

BACKGROUND. The Vesical Imaging Reporting and Data System (VI-RADS), based on multiparametric MRI (mpMRI), was developed to provide accurate information for the diagnosis of muscle-invasive bladder cancer (MIBC). OBJECTIVE. The purpose of our study was to evaluate the interobserver agreement and diagnostic performance of VI-RADS among readers with different levels of experience. METHODS. This retrospective study included 91 consecutive patients who underwent mpMRI before transurethral resection of bladder tumor (TURBT) from July 2010 through August 2018. After attending a training session, seven radiologists (five radiologists experienced in bladder MRI and two inexperienced radiologists) reviewed and scored all MRI examinations according to VI-RADS. The interobserver agreement was assessed by kappa statistics. ROC analysis was used to evaluate the diagnostic performance for MIBC. AUCs were estimated. RESULTS. Among 91 patients (72 men and 19 women; mean age ± SD, 73.2 ± 10.2 years), 48 (52.7%) had MIBC and 43 (47.3%) had non-muscle-invasive bladder cancer. Sixty-eight patients were treated with TURBT, and 23 were treated with radical cystectomy. Interobserver agreement was moderate to substantial (κ = 0.60-0.80) among the experienced readers, substantial (κ = 0.67) between the two inexperienced readers, and moderate to substantial (κ = 0.55-0.75) between the experienced and inexperienced readers. The pooled AUC was 0.88 (range, 0.82-0.91) for experienced readers and 0.84 (range, 0.83-0.85) for inexperienced readers, and 0.87 for all readers. Using a VI-RADS score of 4 or greater as the cutoff value for MIBC, the pooled sensitivity and specificity were 74.1% (range, 66.0-80.9%) and 94.1% (range, 88.6-97.7%) for experienced readers and 63.9% (range, 59.6-68.1%) and 86.4% (range, 84.1-88.6%) for inexperienced readers. Using a VI-RADS score of 3 or greater as the cutoff value, the pooled sensitivity and specificity were 83.4% (range, 80.9-85.1%) and 77.3% (range, 61.4-88.6%) for experienced readers and 82.0% (range, 80.9-83.0%) and 73.9% (range, 72.7-75.0%) for inexperienced readers. CONCLUSION. We observed moderate to substantial interobserver agreement and a pooled AUC of 0.87 among radiologists of different levels of expertise using VI-RADS. CLINICAL IMPACT. VI-RADS could help determine the depth and range of excision in TURBT, decreasing the risk of complications and enhancing the accuracy of pathologic diagnosis.

Efficacy of superselective transcatheter arterial embolization for intractable postpartum hemorrhage due to genital tract trauma after vaginal delivery.

PURPOSE: To evaluate the efficacy of superselective transcatheter arterial embolization (TAE) for intractable postpartum hemorrhage (PPH) due to genital tract trauma (GTT) after vaginal delivery. METHODS: We evaluated 27 patients who underwent TAE for intractable PPH due to GTT after vaginal delivery at our institution between January 2008 and December 2020. Patients were divided into two groups according to TAE procedure; TAE performed as close as possible to the bleeding point, at least more peripherally than the second branch of the anterior division of the internal iliac artery, was defined as superselective TAE (S-TAE). TAE performed from the proximal segment of the internal iliac artery was defined as proximal TAE (P-TAE). Patient characteristics, pre-procedural contrast-enhanced computed tomography (CE-CT), procedure details, technical/clinical success, and complications were evaluated separately for the S-TAE and P-TAE groups. RESULTS: The combined technical/clinical success rate was 92%. No major procedure-related complications were seen (mean follow-up: 6.12 ± 3.93 days). The combined technical/clinical success rate of S-TAE was 100% and of P-TAE was 67% (p = 0.04). S-TAE was performed more frequently in patients with pre-procedural CE-CT (p = 0.01) and use of permanent embolic materials (p = 0.003). CONCLUSION: S-TAE is safe and effective for intractable PPH due to GTT. Pre-procedural CE-CT may be useful for detecting the culprit artery and be helpful in performing S-TAE.

Dual-frequency MR elastography to differentiate between inflammation and fibrosis of the liver: Comparison with histopathology.

BACKGROUND: Differentiation between inflammation and fibrosis is an important clinical distinction in patients with chronic liver disease, which has been difficult so far with MR elastography. PURPOSE: To investigate whether dual-frequency MR elastography can estimate necroinflammation of the liver and improve diagnostic performance for the staging of liver fibrosis. STUDY TYPE: Retrospective. SUBJECTS: In all, 30 patients (14 males, 16 females) with chronic liver disease. FIELD STRENGTH/SEQUENCE: 1.5T/dual-frequency MR elastography at 60-Hz and 80-Hz vibration frequencies. [Correction added on November 12, 2019, after first online publication: The field strength in the preceding sentence was corrected.] ASSESSMENT: Necroinflammation activity and fibrosis were assessed using the METAVIR scoring system. Stiffness values at 60-Hz (G60-Hz ) and 80-Hz (G80-Hz ) were obtained with an MR elastogram. The difference value between G80-Hz and G60-Hz (ΔG) was calculated. Four values (G60-Hz , G80-Hz , G60-Hz - ΔG, and G80-Hz + ΔG) were generated to estimate necroinflammation and fibrosis. STATISTICAL TESTS: The ΔG were correlated with necroinflammation activity grade and fibrosis stage using Spearman's rank correlation. Diagnostic performance of the four values for necroinflammation activity grade and fibrous stage was assessed by using area under the receiver operating characteristic curve (AUC). RESULTS: The mean value of G80-Hz (6.23 ± 3.67 kPa) was significantly higher than that of G60-Hz (5.27 ± 3.14 kPa) (P < 0.0001). The ΔG demonstrated a strong correlation with necroinflammation grade (ρ = 0.625, P < 0.001) and no correlation with fibrosis stage (ρ = 0.306, P = 0.113). The AUC of the G80-Hz and G80-Hz + ΔG showed higher accuracy for necroinflammation, and optimal cutoff values yielded better discrimination of ≥A1, ≥A2, and = A3. The AUC demonstrated that all the generated values had high diagnostic performance (≥0.87 for all) for fibrosis. DATA CONCLUSION: Dual-frequency MR elastography shows potential in estimating necroinflammation of the liver and may improve diagnostic performance for staging liver fibrosis. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:1053-1064.

Diagnostic performance of zero-TE lung MR imaging in FDG PET/MRI for pulmonary malignancies.

OBJECTIVES: This study aimed to evaluate the diagnostic performance of the lung zero-echo time (ZTE) sequence in FDG PET/MRI for detection and differentiation of lung lesions in oncologic patients in comparison with conventional two-point Dixon-based MR imaging. METHODS: In this single-institution retrospective study approved by the institutional review board, 209 patients with malignancies (97 men and 112 women; age range, 17-89 years; mean age, 66.5 ± 12.9 years) underwent 18F-FDG PET/MRI between August 2017 and August 2018, with diagnostic Dixon and ZTE under respiratory gating acquired simultaneously with PET. Image analysis was performed for PET/Dixon and PET/ZTE fused images by two readers to assess the detectability and differentiation of lung lesions. The reference standard was pathological findings and/or the data from a chest CT. The detection and differentiation abilities were evaluated for all lesions and subgroups divided by lesion size and maximum standardized uptake value (SUVmax). RESULTS: Based on the reference standard, 227 lung lesions were identified in 113 patients. The detectability of PET/ZTE was significantly better than that of PET/Dixon for overall lesions, lesions with a SUVmax less than 3.0 and lesions smaller than 4 mm (p < 0.01). The diagnostic performance of PET/ZTE was significantly better than that of PET/Dixon for overall lesions and lesions smaller than 4 mm (p < 0.01). CONCLUSIONS: ZTE can improve diagnostic performance in the detection and differentiation of both FDG-avid and non-FDG-avid lung lesions smaller than 4 mm in size, yielding a promising tool to enhance the utility of FDG PET/MRI in oncology patients with lung lesions. KEY POINTS: • The detection rate of PET/ZTE for lesions with a SUVmax of less than 1.0 was significantly better than that of PET/Dixon. • The performance for differentiation of PET/ZTE for lesions that were even smaller than 4 mm in size were significantly better than that of PET/Dixon. • Inter-rater agreement of PET/ZTE for the differentiation of lesions less than 4 mm in size was substantial and better than that of PET/Dixon.

Improved Visualization and Identification of the Right Adrenal Vein in 70-kVp Contrast-Enhanced Computed Tomography.

OBJECTIVE: The aim of this study was to assess the utility of 70-kilovoltage-peak (kVp) contrast-enhanced computed tomography (CECT) for visualization and identification of the right adrenal vein (RAV) in comparison with that of conventional 120-kVp CECT. METHODS: This retrospective study included patients who underwent adrenal venous sampling with concurrent biphasic 120-kVp (120-kVp group, n = 43) or 70-kVp (70-kVp group, n = 47) CECT. Signal-to-noise ratios, contrast-to-noise ratios, longitudinal lengths, conspicuity scores, RAV detection rates, and size-specific dose estimates were compared between the 2 groups. RESULTS: In comparison with the 120-kVp group, the 70-kVp group had significantly higher signal-to-noise and contrast-to-noise ratios (P < 0.001-P = 0.033), greater longitudinal lengths (P < 0.001-P = 0.002), superior conspicuity scores for the RAV (P < 0.001), higher RAV detection rates (P = 0.015-P = 0.033), and lower size-specific dose estimates (P < 0.001). CONCLUSIONS: Seventy-kilovoltage-peak CECT has advantages over conventional 120-kVp CECT and is potentially useful for noninvasive assessment of the precise anatomy of the RAV.

Assessment of lenvatinib treatment for unresectable hepatocellular carcinoma with liver cirrhosis.

BACKGROUND: The present study aimed to assess the clinical features of patients who received lenvatinib treatment for unresectable hepatocellular carcinoma (HCC). METHODS: The clinical characteristics, adverse events, and radiological responses were evaluated for 51 consecutive patients. RESULTS: Of the study subjects, 37 patients had Child-Pugh class A (CPA) liver function, and 14 patients had Child-Pugh class B (CPB) liver function. The overall response rates in the CPA and CPB groups were 42.9% and 25.0%, respectively, and disease control rates were 82.9% and 83.3%, respectively, without significant difference (p = 0.2621 and 0.9697). There was no significant difference between CPA and CPB groups regarding the incidence of adverse events, except for hepatic coma. No significant difference was observed in the relative dose intensity between the CPA and CPB groups, for the first month, 1-2 months, or 2-3 months (p = 0.2368, 0.9368, and 0.9293). CONCLUSION: The comparable outcomes between the CPA and CPB groups suggest the acceptability of lenvatinib treatment in patients with impaired liver function, at least in the acute phase. With careful follow-up, the dose can be relatively intensified, even in patients with impaired liver function and this may contribute to offering comparable treatment.