Non-alcoholic steatohepatitis (NASH) is a complex disease consisting of various components including steatosis, lobular inflammation, and ballooning degeneration, with or without fibrosis. Therefore, it is difficult to diagnose NASH with only one imaging modality. This study was aimed to evaluate the feasibility of magnetic resonance imaging (MRI) for predicting NASH and to develop a non-invasive multiparametric MR index for the detection of NASH in non-alcoholic fatty liver disease (NAFLD) patients. This prospective study included 47 NAFLD patients who were scheduled to undergo or underwent ultrasound-guided liver biopsy within 2 months. Biopsy specimens were graded as NASH or non-NASH. All patients underwent non-enhanced MRI including MR spectroscopy (MRS), MR elastography (MRE), and T1 mapping. Diagnostic performances of MRS, MRE, and T1 mapping for grading steatosis, activity, and fibrosis were evaluated. A multiparametric MR index combining fat fraction (FF), liver stiffness (LS) value, and T1 relaxation time was developed using linear regression analysis. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance of the newly devised MR index. Twenty NASH patients and 27 non-NASH patients were included. Using MRS, MRE, and T1 mapping, the mean areas under the curve (AUCs) for grading steatosis, fibrosis, and activity were 0.870, 0.951, and 0.664, respectively. The multiparametric MR index was determined as 0.037 × FF (%) + 1.4 × LS value (kPa) + 0.004 × T1 relaxation time (msec) −3.819. ROC curve analysis of the MR index revealed an AUC of 0.883. The cutoff value of 6 had a sensitivity of 80.0% and specificity of 85.2%. The multiparametric MR index combining FF, LS value, and T1 relaxation time showed high diagnostic performance for detecting NASH in NAFLD patients.

PurposeBreast cancer has a high prevalence in Korea. To achieve personalized therapy for breast cancer, long-term follow-up specimens are needed for next-generation sequencing (NGS) and multigene analysis. Formalin-fixed paraffin-embedded (FFPE) samples are easier to store than fresh frozen (FF) samples. The objective of this study was to optimize RNA extraction from FFPE blocks for NGS.MethodsRNA quality from FF and FFPE tissues (n=5), expected RNA amount per unit area, the relationship between archiving time and quantity/quality of FFPE-extracted RNA (n=14), differences in quantitative real-time polymerase chain reaction (qRT-PCR) and NGS results, and comparisons of both techniques with tissue processing at different institutions (n=96) were determined in this study.ResultsThe quality of RNA did not show any statistically significant difference between paired FF and FFPE specimens (p=0.49). Analysis of tumor cellularity gave an expected RNA amount of 33.25 ng/mm2. Archiving time affected RNA quality, showing a negative correlation with RNA integrity number and a positive correlation with threshold cycle. However, RNA from samples as old as 10 years showed a 100% success rate in qRT-PCR using short primers, showing that the effect of archiving time can be overcome by proper experiment design. NGS showed a higher success rate than qRT-PCR. Specimens from institution B (n=46), which were often stored in a refrigerator for more than 6 hours and fixed without slicing, showed lower success rates and worse results than specimens from the other institutes.ConclusionArchived FFPE tissues can be used to extract RNA for NGS if they are properly processed before fixation. The expected amount of RNA per unit size calculated in this study will be useful for other researchers.

Epithelioid angiomyolipoma (EAML) of liver is a rare neoplasm. Hepatic EAML is often misdiagnosed as other neoplasms such as hepatocellular carcinoma due to non-specific clinical and radiologic features. The morphologic features under microscope and immunohistochemistry staining profile are important in the diagnosis EAML. Here, we report a case of 52-year-old man who found 1.2 cm mass in liver by routine checkup. On the impression of hepatocellular carcinoma, lateral sectionectomy of the liver was done. Microscopically, the tumor is composed of predominant epithelioid cells with vascular component and foamy cells. These cells were positive for HMB45, MelanA, and smooth muscle actin and negative for epithelial membrane antigen. The final diagnosis was hepatic EAML.

INTRODUCTION: Because nonalcoholic fatty liver disease (NAFLD) is becoming a leading cause of chronic liver disease, noninvasive evaluations of its severity are immediately needed. This prospective cross-sectional study evaluated the effectiveness of noninvasive assessments of hepatic steatosis, fibrosis, and steatohepatitis. METHODS: Patients underwent laboratory tests, liver biopsy, transient elastography, and MRI. Multiparametric MR was used to measure MRI proton density fat fraction, MR spectroscopy, T1 mapping, and MR elastography (MRE). RESULTS: We enrolled 130 patients between October 2016 and July 2019. For the diagnosis of moderate-to-severe steatosis (grade ≥ 2), the area under the receiver operating characteristic curve (AUROC) was lower in controlled attenuation parameter (0.69; 95% confidence interval [CI], 0.60–0.76) than MRI proton density fat fraction (0.82; 95% CI, 0.75–0.89; P = 0.008) and MR spectroscopy (0.83; 95% CI, 0.75–0.89; P = 0.006). For the diagnosis of advanced fibrosis (stage ≥ 3), the AUROC of MRE (0.89; 95% CI, 0.83–0.94) was superior compared with those of the Fibrosis-4 index (0.77; 95% CI, 0.69–0.84; P = 0.010), NAFLD fibrosis score (0.81; 95% CI, 0.73–0.87; P = 0.043), and transient elastography (0.82; 95% CI, 0.74–0.88; P = 0.062). For detecting advanced fibrosis or nonalcoholic steatohepatitis, the AUROC of MRE (0.86; 95% CI, 0.79–0.91) was higher than that of TE (0.76; 95% CI, 0.68–0.83) with statistical significance (P = 0.018). DISCUSSION: Multiparametric MR accurately identified a severe form of NAFLD. Multiparametric MR can be a valuable noninvasive method for evaluating the severity of NAFLD.

Background: The accurate pathologic diagnosis and subtyping of high-grade endometrial carcinoma are often problematic, due to its atypical and overlapping histopathological features. Methods: Three pathologists reviewed 21 surgically resected cases of advancedstage endometrial carcinoma. The primary diagnosis was based only on hematoxylin and eosin stained slides. When a discrepancy arose, a secondary diagnosis was made by additional review of immunohistochemical (IHC) stains. Finally, three pathologists discussed all cases and rendered a consensus diagnosis. Results: The primary diagnoses were identical in 13/21 cases (62%). The secondary diagnosis based on the addition of IHC results was concordant in four of eight discrepant cases. Among four cases with discrepancies occurring in this step, two cases subsequently reached a consensus diagnosis after a thorough discussion between three reviewers. Next-generation sequencing (NGS) study was performed in two cases in which it was difficult to distinguish between serous carcinoma and endometrioid carcinoma. Based on the sequencing results, a final diagnosis of serous carcinoma was rendered. The overall kappa for concordance between the original and consensus diagnosis was 0.566 (moderate agreement). Conclusions: We investigated stepwise changes in interobserver diagnostic reproducibility in advanced-stage endometrial carcinoma. We demonstrated the utility of IHC and NGS study results in the histopathological diagnosis of advanced-stage endometrial carcinoma.