Pediatric Hepatoblastoma After Neoadjuvant Chemotherapy: Diagnostic Performance of MR in Staging POSTTEXT and Vascular Involvement.

BACKGROUND: The assessment of resectability after neoadjuvant chemotherapy of hepatoblastoma is dependent on Post-Treatment EXTENT of Disease (POSTTEXT) staging and its annotation factors P (portal venous involvement) and V (hepatic venous/inferior vena cava [IVC] involvement), but MR performance in assessing them remains unclear. PURPOSE: To assess the diagnostic performance of contrast-enhanced MR imaging for preoperative POSTTEXT staging and diagnosing vascular involvement in terms of annotation factors P and V in pediatric hepatoblastoma following neoadjuvant chemotherapy. STUDY TYPE: Retrospective. SUBJECTS: Thirty-five consecutive patients (17 males, median age, 24 months; age range, 6-98 months) with proven hepatoblastoma underwent preoperative MR imaging following neoadjuvant chemotherapy. FIELD STRENGTH/SEQUENCE: 3.0 T; T2-weighted imaging (T2WI), T2WI with fat suppression, diffusion weighted imaging, radial stack-of-the-star/Cartesian 3D Dixon T1-weighted gradient echo imaging. ASSESSMENT: Three radiologists independently assessed the POSTTEXT stages and annotation factors P and V based on the 2017 PRE/POSTTEXT system. The sensitivities and specificities were calculated for 1) diagnosing each POSTTEXT stage; 2) discrimination of stages III and IV (advanced) from those stages I and II (non-advanced) hepatoblastomas; and 3) annotation factors P and V. The combination of pathologic findings and surgical records served as the reference standard. STATISTICAL TESTS: Sensitivity, specificity, Fleiss kappa test. RESULTS: The sensitivity and specificity ranges for discriminating advanced from non-advanced hepatoblastomas were 73.3%-80.0% and 80.0%-90.0%, respectively. For annotation factor P, they were 66.7%-100.0% and 90.6%, respectively. For factor V, they were 75.0% and 67.7%-83.9%, respectively. There was excellent, substantial, and moderate agreement on POSTTEXT staging (Fleiss kappa = 0.82), factors P (Fleiss kappa = 0.64), and factors V (Fleiss kappa = 0.60), respectively. DATA CONCLUSION: MR POSTTEXT provides reliable discrimination between advanced and non-advanced tumors, and MR has moderate to excellent specificity at identifying portal venous and hepatic venous/IVC involvement. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.

Overexpression of miR-126 inhibits the activation and migration of HSCs through targeting CRK.

BACKGROUND & AIMS: MicroRNAs (miRNAs) have been shown to play essential roles in HSCs activation which contributes to hepatic fibrosis. Our previous miRNA microarray results suggested that miR-126 might be decreased during HSCs activation as other studies. The aim of this study is to investigate the role of miR-126 during HSCs activation. METHODS: In this study, the expression of miR-126 during HSCs activation was measured and confirmed by qRT-PCR. Then, miR-126 expression was restored by transfection of lentivirus vector encoding miR-126. Futhermore, cell proliferation was assayed by the cell counting kit-8 (CCK-8), cell migration was assayed by transwell assay, and the markers of activation of HSCs, α-SMA and collagen type I, were assayed by qRT-PCR, Western Blotting, Immunostaining and ELISA. Luciferase reporter assay was used to find the target of miR-126, and Western Blotting and Immunostaining was used to validate the target of miR-126. Then, the expression and the role of the target of miR-126 during HSCs activation was further assessed. RESULTS: The expression of miR-126 was confirmed to be significantly decreased during HSCs activation. Overexpression of miR-126 significantly inhibited HSCs migration but did not affect HSCs proliferation. The expression of α-SMA and collagen type I were both obviously decreased by miR-126 restoration. CRK was found to be the target of miR-126 and overexpression of miR-126 significantly inhibited CRK expression. And it was found that overexpression of CRK also significantly decreased miR-126 expression and promoted HSCs activation. CONCLUSIONS: Our study showed that overexpression of miR-126 significantly inhibited the activation and migration of HSCs through targeting CRK which can also decrease miR-126 expression and promote HSCs activation.

Atypical and uncommon CT and MR imaging presentations of pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinomas (PDACs) occasionally have atypical and uncommon imaging presentations that can present a diagnostic dilemma and result in false interpretation. This article aimed to illustrate these CT and MR imaging findings, including isoattenuating PDAC, coexisting acute pancreatitis, PDAC with a cystic feature, groove PDAC, diffuse PDAC, hypointensity on diffusion-weighted imaging (DWI), multifocal PDAC, intratumoral calcification, and extrapancreatic invasion with a barely discernable mass. A subset of PDACs with atypical features are occasionally encountered during routine clinical practice. Knowledge of and attention to these atypical and uncommon variable imaging features may allow radiologists to avoid misinterpretation and a delayed diagnosis.

Differentiation of cancerous and inflammatory colorectal perforations using multi-detector computed tomography.

PURPOSE: To determine reliable CT features to distinguish cancerous from inflammatory colorectal perforations. MATERIALS AND METHODS: A total of 43 patients with surgically and pathologically confirmed colorectal perforation caused by either colorectal cancer (n =27) or an inflammatory conditions (n = 16) were identified. Two radiologists independently assessed the contrast-enhanced CT features for locations of perforation, mural configurations, soft-tissue alterations, lymphadenopathy, and metastases. Intergroup comparisons for univariate analysis were performed using Fisher's exact test or chi-square test for categorical data and Mann-Whitney test for numeric data. Stepwise logistic regression analysis was conducted with features that were found significant under the univariate analysis. Interobserver agreement was assessed using intraclass correlation coefficient (ICC) and kappa test. RESULTS: Maximal mural thickness >1.39 cm (sensitivity, 100%; specificity, 68.75%), luminal mass or shoulder formation (sensitivity, 88.89%; specificity, 68.75%), absence of diverticula (sensitivity, 96.30%; specificity, 50.00%), irregular mural thickening (sensitivity, 92.59%; specificity, 81.25%), lymphadenopathy (sensitivity, 40.74%; specificity, 93.75%), and metastases (sensitivity, 25.93%; specificity, 100%) were significantly frequent in cancerous perforations. The maximal mural thickness (P = 0.0493, odds ratio = 439.83) and irregular mural thickening (P = 0.0343, odds ratio = 4.69) were identified as the highly distinguished identifiers. CONCLUSIONS: The CT manifestations of cancerous and inflammatory colorectal perforations overlap. Definitive diagnosis is not always possible with imaging alone. The maximal mural thickness >1.39 cm and irregular configuration of the thickened bowel wall were the two highly statistically significant CT features that may help order the difference between the two entities.