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BackgroundIn a 72-week, randomised controlled trial of obeticholic acid (OCA) in non-alcoholic steatohepatitis (NASH), OCA was superior to placebo in improving serum ALT levels and liver histology. OCA therapy also reduced weight.AimsBecause weight loss by itself can improve histology, to perform a post hoc analysis of the effects of weight loss and OCA treatment in improving clinical and metabolic features of NASH.MethodsThe analysis was limited to the 200 patients with baseline and end-of-treatment liver biopsies. Weight loss was defined as a relative decline from baseline of 2% or more at treatment end.ResultsWeight loss occurred in 44% (45/102) of OCA and 32% (31/98) of placebo-treated patients (P = 0.08). The NAFLD Activity score (NAS) improved more in those with than without weight loss in both the OCA- (-2.4 vs -1.2, P

Zygomycosis is a rare invasive opportunistic fungal infection that occurs in the setting of hematologic malignancies, chemotherapy-induced neutropenia, and immunosuppressive therapies. We report the first case of disseminated appendiceal zygomycosis due to

Fusobacterium is well characterized as an oropharyngeal pathogen that may induce a septic thrombophlebitis by direct extension of abscess into an adjacent neck vessel (Lemierre's syndrome); its potential for visceral abscess formation, however, remains und

Aims: Activation of phosphoinositide-3 kinase (PI3K) is essential for cell growth, relating to adaptive and maladaptive cardiac hypertrophy. This longitudinal canine study was designed to investigate the role of PI3Kalpha and PI3Kgamma in cardiac remodelling during congestive heart failure (CHF) and cardiac recovery (CR). Methods and Results: All dogs were surgically instrumented. Congestive heart failure was induced by cardiac pacing for 3-4 weeks and CR was allowed by terminating pacing for 5-6 weeks after induction of HF. Control dogs had sham surgery, but did not undergo pacing. Left ventricular (LV) contractile function was depressed in CHF and restored to 80-90% of the normal level in CR, with a 25% increase in LV weight. The expression of PI3Kgamma was increased four-fold in CHF, but returned to control levels in CR. In contrast, the expression of PI3Kalpha in CHF was not different from that in controls, but increased three-fold in CR and was accompanied by increases in phosphorylation of Akt (five-fold), GSK-3beta (five-fold), beta-catenin (three-fold), mTOR (two-fold), and P70S6K (two-fold). Conclusion: Our results indicate that PI3K isoforms are regulated differently during the course of CHF/CR and that the selective activation of PI3Kalpha, through Akt, GSK-3beta, and mTOR signalling pathways, may be involved in the development of cardiac compensatory hypertrophy and functional restoration. [ABSTRACT FROM AUTHOR]

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) is common in people with HIV (PWH). The morphological spectrum of MASLD compared to matched controls and of the correlation between the NAFLD activity score (NAS) and fibrosis stage in PWH remains unknown., Methods: Overall, 107 liver biopsies from PWH with MASLD (MASLD-PWH) were matched to 107 biopsies from individuals with MASLD and without HIV (MASLD controls) on age at biopsy, race/ethnicity, sex, type 2 diabetes, body mass index (BMI) and alanine aminotransferase (ALT) level. Biopsies were scored using NAS., Results: Compared to MASLD-controls, MASLD-PWH had lower steatosis grade (OR: 0.65, 95% CI: (0.47-0.90), p = 0.01), lower lobular inflammation grade (OR: 0.55, 95% CI: (0.34-0.89), p = 0.02), less portal inflammation (OR: 0.42, 95% CI: (0.25-0.72), p = 0.002) and less ballooned hepatocytes (OR: 0.60, 95% CI: (0.41-0.88), p = 0.01). Thus, NAS was lower in MASLD-PWH (OR: 0.69, 95% CI: (0.56-0.85), p < 0.001) than in MASLD controls. There was a trend towards lower prevalence of steatohepatitis in MASLD-PWH (OR: 0.84, 95% CI: (0.68-1.03), p = 0.09). A multivariate analysis demonstrated that MASLD-PWH cases had significantly less steatosis (OR: 0.66, p = 0.03), portal inflammation (OR: 0.34, p = 0.001) and ballooned hepatocytes (OR: 0.55, p = 0.01), yet higher stage fibrosis (OR: 1.42, p = 0.03) compared to MASLD controls., Conclusion: The NAS and histological drivers of fibrosis (e.g. inflammation and hepatocyte ballooning) are less pronounced in MASLD-PWH, and yet fibrosis stage was generally higher when compared to matched controls with MASLD without HIV. This suggests HIV-specific factors beyond hepatic necroinflammation may contribute to fibrosis progression in MASLD-PWH., (© 2024 The Author(s). Alimentary Pharmacology & Therapeutics published by John Wiley & Sons Ltd. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)

Aims: Although turmeric is commonly ingested and well tolerated, there is increasing evidence that over-the-counter turmeric supplements can cause drug-induced liver injury. We sought to thoroughly characterise clinicopathological features of patients for whom liver injury was attributed clinically to turmeric supplements., Methods and Results: We identified 11 patients via retrospective pathology archive review: 10 females (91%) and one male, with a median age of 58 years (range = 37-66 years). Six patients (55%) were asymptomatic with abnormal liver function tests, while five patients (45%) presented with malaise and/or jaundice. Ten patients (91%) showed predominant transaminase abnormalities, while one exhibited predominant alkaline phosphatase elevation. Histologically, biopsies showed acute hepatitis (eight cases, 73%, including five pan-lobular and three zone 3-predominant inflammation), scattered lobular aggregates of histiocytes (two; 18%) and a chronic hepatitis pattern of injury (one; 9%). Mild bile duct injury was present in five biopsies (45%). All patients stopped ingesting turmeric supplements after presenting with liver injury, and four patients additionally received steroid therapy; liver function tests normalised in all patients. Roussel Uclaf causality assessment method (RUCAM) analysis estimated the likelihood of turmeric supplement-associated liver injury to be probable (eight cases) and possible (three)., Conclusions: Histological features in the 'possible' cases were consistent with drug-induced injury, highlighting the added benefit of histological analysis relative to RUCAM analysis isolation. This study underscores the need to obtain a full history of over-the-counter medications and supplements when investigating aetiologies for liver injury, including supplements purportedly containing innocuous compounds such as turmeric., (© 2024 John Wiley & Sons Ltd.)

Aims: There is great variability in the assessment and reporting of fat in frozen sections of donor liver biopsies. The Banff Working Group has proposed a novel method and definition for scoring large droplet fat (LDF) in donor liver biopsies. This study compares the Banff method with a simpler Average of Fields (AF) method and evaluates the impact of different LDF definitions., Methods: Three pathologists assessed percentage of LDF (LDF%) in 10 donor liver biopsies using Banff and AF methods, applying the Banff LDF definition (cell distention with a single droplet larger than adjacent hepatocytes). Additionally, LDF% by the AF method was compared using two LDF definitions: Banff definition versus LDF definition 2 (single fat droplet occupying greater than half of a hepatocyte with nuclear displacement)., Results: Intraobserver concordance between the Banff and AF methods was similar for all three pathologists (kappa 0.76-1). Both methods exhibited 70% interobserver concordance, and there was substantial agreement (kappa 0.68) in the LDF% among the three pathologists for both methods. Comparing the two LDF definitions, results were significantly lower with the Banff definition; LDF >50% was observed in four cases with LDF definition 2 but none of the cases with the Banff definition., Conclusions: There is high interobserver and intraobserver concordance of LDF% between the Banff and AF methods. LDF% determined by the Banff definition was lower than with LDF definition 2, and needs to be validated based on graft outcome before it can be recommended for clinical use., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Hemophagocytic lymphohistiocytosis (HLH) is a rare disease with high mortality. Liver involvement is common (based on elevated liver function tests) with most patients demonstrating acute hepatitis. Liver biopsies are frequently obtained in the setting of suspected HLH for the purpose of identification of erythrophagocytosis, and if present, this finding is thought to suggest or support the diagnosis of HLH. However, there are problems with this approach; in particular, we do not know whether this finding is reproducible or whether it is specific to HLH. Therefore, we conducted a multi-institutional study in which experienced liver pathologists reviewed images taken from liver biopsies from patients with normal liver, acute hepatitis, possible HLH, and clinical HLH to determine if there was agreement about the presence or absence of erythrophagocytosis, and to ascertain whether the finding corresponds to a clinical diagnosis of HLH. Twelve liver pathologists reviewed 141 images in isolation (i.e., no clinical information or diagnosis provided). These came from 32 patients (five normal, 17 acute hepatitis, six HLH, four possible HLH). The pathologists classified each image as negative, equivocal, or positive for erythrophagocytosis. Kappa was .08 (no agreement) for case-level and 0.1 for image-level (1.4% agreement, based on two images which were universally considered negative). There was no difference in the proportion of pathologists who diagnosed erythrophagocytosis among those with different diagnoses at case or image-level (p = 0.82 and p = 0.82, respectively). Thus, erythrophagocytosis is an entirely unreliable histologic parameter in liver, as it is irreproducible and not demonstrably associated with a clinical disease (namely, HLH). Unless and until more reliable guidelines can be established, pathologists should refrain from commenting on the presence or absence of erythrophagocytosis in liver biopsy., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background The Liver Imaging Reporting and Data System version 2018 (LI-RADS) treatment response algorithm (TRA) is a high-specificity, lower-sensitivity grading system to diagnose hepatocellular carcinoma (HCC) and recurrence after local-regional therapy. However, the emphasis on specificity can result in disease understaging, potentially leading to poorer posttransplant outcomes. Purpose To determine the negative predictive value (NPV) of pretransplant CT and MRI assessment for viable HCC on a per-patient basis using the LI-RADS TRA, considering explant pathology as the reference standard. Materials and Methods Patient records from 218 consecutive adult patients from a single institution with HCC who underwent liver transplant from January 2011 to November 2017 were retrospectively reviewed. Two readers blinded to the original report reviewed immediate (within 90 days) pretransplant imaging and characterized observations according to the LI-RADS TRA. Based on this, patients with LR-4, LR-5, or LR-TR (treatment response) viable tumors were designated as viable tumor; patients with solely LR-3 or LR-TR equivocal tumors were designated as equivocal; and patients with only LR-TR nonviable lesions were designated as no viable disease. Patients were designated as within or outside the Milan criteria. These per-patient designations were compared with the presence of viable disease at explant pathology. Fisher exact test was used to compare the differences between CT and MRI. Weighted κ values were used to calculate interreader reliability. Results Final study sample consisted of 206 patients (median age, 61 years [IQR, 57-65 years]; 157 male patients and 49 female patients). Per-patient LI-RADS TRA assessment of pretransplant imaging had an NPV of 32% (95% CI: 27, 38) and 26% (95% CI: 20, 33) (readers 1 and 2, respectively) for predicting viable disease. Seventy-five percent (reader 1) and 77% (reader 2) of patients deemed equivocal had residual tumors at explant pathology. Weighted interreader reliability was substantial (κ = 0.62). Conclusion Patient-based stratification of viable, equivocal, and nonviable disease at pretransplant CT or MRI, based on LI-RADS TRA, demonstrated low negative predictive value in excluding HCC at explant pathology. © RSNA, 2023 See also the editorial by Tamir and Tau in this issue.

Leukocyte telomere length (LTL) gets shorter with each cell division and is also sensitive to reactive oxygen species damage and inflammatory processes. Studies in adults with non-alcoholic fatty liver disease (NAFLD) have found that increased fibrosis but not ALT levels are associated with shorter LTL. Few pediatric studies have been conducted; as such, we sought to evaluate potential associations between LTL and liver disease and liver disease progression in pediatric patients. Using data from the Treatment of NAFLD in Children (TONIC) randomized controlled trial, we assessed the potential predictive relationship between LTL and liver disease progression based on two successive liver biopsies over 96 weeks. We assessed the potential relationship between LTL and child age, sex, and race/ethnicity and features of liver disease including components of histology. We subsequently evaluated predictors for improvement in non-alcoholic steatohepatitis (NASH) at 96 weeks including LTL. We also assessed predictors of lobular inflammation improvement at 96 weeks using multivariable models. Mean LTL at baseline was 1.33 ± 0.23 T/S. Increasing lobular and portal inflammation were associated with longer LTL. In multivariable models, greater lobular inflammation at baseline was associated with longer LTL (Coeff 0.03, 95% CI 0.006-0.13; p = 0.03). Longer LTL at baseline was associated with worsening lobular inflammation at 96 weeks (Coeff 2.41, 95% CI 0.78-4.04; p < 0.01). There was no association between liver fibrosis and LTL. The association between LTL and pediatric NASH does not parallel adults with no association between fibrosis stage and NASH. Conversely, longer LTL was associated with more lobular inflammation at baseline and increased lobular inflammation over the 96-week period. Longer LTL in children may indicate greater risk for future complications from NASH., (© 2023. The Author(s).)

Distinguishing grade 3 pancreatic neuroendocrine tumor (G3 PanNET) from neuroendocrine carcinoma (PanNEC) is a known diagnostic challenge, and accurate classification is critical because clinical behavior and therapies differ. Although current recommendations suggest that immunohistochemistry for p53, Rb, ATRX, and DAXX can distinguish most cases, some cases remain difficult to classify using this approach. In this study, we reviewed 47 high-grade neoplasms originally diagnosed as pancreatic neuroendocrine neoplasms. In addition to the currently recommended stains, we performed capture-based sequencing of approximately 500 cancer genes and immunohistochemistry for p16 and trypsin or chymotrypsin. Using an integrated molecular and clinicopathologic approach, 42 (89%) of 47 cases had a clear final diagnosis of either G3 PanNET (n = 17), PanNEC (n = 17), or mixed acinar-NEC (n = 8). The 17 G3 PanNETs demonstrated frequent alterations in MEN1 (71%), DAXX (47%), ATRX (24%), TSC2 (35%), SETD2 (42%), and CDKN2A (41%). Contrary to prior reports, TP53 alterations were also common in G3 PanNETs (35%) but were always mutually exclusive with CDKN2A alterations in this group. The 17 PanNECs demonstrated frequent alterations in TP53 (88%), cell cycle genes RB1 (47%), CCNE1/CCND1 (12%), CDKN2A (29%), and in KRAS (53%) and SMAD4 (41%); TP53 was coaltered with a cell cycle gene in 76% of PanNECs. Diffuse strong p16 staining was observed in 69% of PanNECs in contrast to 0% of G3 PanNETs. The 8 acinar-NECs had recurrent alterations in ATM (25%), APC (25%), and STK11 (25%). Five cases remained difficult to classify, 3 of which exhibited overlapping molecular features with alterations in MEN1 with or without ATRX, and RB1 with or without TP53, making it unclear whether to classify as PanNET or PanNEC. Our data demonstrate that molecular profiling and immunohistochemistry for p16 greatly improve the diagnostic accuracy of high-grade pancreatic neuroendocrine neoplasms and identify a subset of rare cases with overlapping features of both PanNET and PanNEC., (Published by Elsevier Inc.)

Background and Aims: The NAFLD activity score was developed to measure histologic changes in NAFLD during therapeutic trials. Hepatocyte ballooning (HB) is the most specific feature in steatohepatitis diagnosis, yet the impact of variations in HB has not been incorporated., Approach and Results: Liver biopsies from patients enrolled in the NASH Clinical Research Network with an initial diagnosis of NASH or NAFL (n=1688) were evaluated to distinguish classic hepatocyte ballooning (cHB) from smaller, nonclassic hepatocyte ballooning (nHB), and also to designate severe ballooning and assign an extended hepatocyte ballooning (eB) score [0 points, no ballooning (NB); 1 point, few or many nHB; 2 points, few cHB; 3 points, many cHB; 4 points, severe cHB] to the biopsy assessment. The eB score was reproducible among NASH CRN liver pathologists (weighted kappa 0.76) and was significantly associated with older age (mean 52.1 y, cHB; 48.5 y, nHB, p<0.001), gender (72.3% female, cHB; 54.5% female, nHB, p<0.001), diabetes (49.8% diabetes, cHB; 28.2% diabetes, nHB, p<0.001), metabolic syndrome (68.5% metabolic syndrome, nHB; 50.2% metabolic syndrome, NB, p<0.001), and body mass index [33.2, 34.2, 35 mean body mass index (kg/m2); NB, nHB, and cHB, respectively, p<0.05]. Finally, fibrosis stage, as a marker of disease severity, was significantly correlated with the eB score (p<0.001)., Conclusions: The eB score allows for a reproducible and more precise delineation of the range of ballooned hepatocyte morphology and corresponds with both clinical features of NASH and fibrosis stage.

Background: Non-alcoholic steatohepatitis (NASH) has become an increasingly recognized problem in patients after orthotopic liver transplant. The aims of this study were to compare the clinicopathologic features of recurrent and de novo NASH., Methods: From 1995 to 2016, we performed a retrospective review of patients with a histological diagnosis of non-alcoholic steatohepatitis made more than 6 months after liver transplant at University of California, San Francisco. The cases were categorized into de novo (n = 19) or recurrent steatohepatitis (n = 37)., Results: Hepatitis C virus (HCV) infection-related cirrhosis was the most common etiology of transplantation in de novo NASH (78% of cases, n = 29). There was no difference in glycogenosis or presence of grade 3 steatosis. More recurrent NASH biopsies had small ballooned hepatocytes (62.5% of cases) compared to de novo NASH (26.7%) (p = 0.03), and were less likely to show prominent portal inflammation (5% versus 40.5%, p = 0.0049). The diagnosis of recurrent NASH was made significantly sooner after transplantation than the diagnosis of de novo NASH (2.8 years versus 4.8 years, p = 0.02)., Conclusions: Overall, our results support that recurrent NASH demonstrates distinct clinicopathologic features compared to de novo NASH arising in the post-transplant setting., (© 2022. The Author(s).)

HNF1A-inactivated hepatocellular adenomas (H-HCA) show steatosis, no atypia and loss of liver fatty acid binding protein (LFABP). LFABP loss also occurs in hepatocellular carcinoma (HCC). This study examines 68 LFABP-negative tumors: 33 typical H-HCA, 10 atypical hepatocellular neoplasms (AHN), 7 well-differentiated (WD) HCC, 18 moderately or poorly differentiated (MD/PD) HCC. Capture based sequencing was performed in 13 cases (8 AHN, 5 WD-HCC). Patients with HCA, AHN and WD-HCC were nearly all women. AHN and WD-HCC resembled H-HCA but had higher degree of atypia and/or reticulin loss. Variant features like inconspicuous fat (59% vs. 12%, p = 0.03), predominance of eosinophilic cells (59% vs. 21%, p = 0.01) and pseudoacini were more common in AHN and WD-HCC. Myxoid change and prominent lipofuscin were more common in WD-HCC (29% each) than H-HCA and AHN combined (2% and 7% respectively). Compared to WD-HCC, LFABP-negative MD/PD HCC were more commonly associated with male gender, viral hepatitis and cirrhosis. Biallelic HNF1A alterations were seen in all 13 (100%) sequenced cases. Additional mutations and/or copy number alterations were observed in 38% of AHN and 100% of WD-HCC. Diffuse glutamine synthetase (GS) staining was seen in 13% of cases, with no nuclear β-catenin or Wnt signaling alterations. In conclusion, variant features such as lack of fat, peliosis, myxoid change, pseudoacini and abundant lipofuscin are more common in AHN and/or WD-HCC. LFABP-negative MD/PD HCC have different clinicopathologic features compared to WD-HCC. The significance of diffuse GS in a subset of these cases is unclear., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Aims: The diagnosis of focal nodular hyperplasia (FNH) and the interpretation of glutamine synthetase (GS) staining can be challenging on biopsies. We aimed to evaluate the reproducibility of needle biopsy diagnosis of FNH, the effect of GS immunohistochemistry on FNH diagnosis, and which histological features are most useful for the diagnosis of FNH., Methods and Results: The study included virtual needle biopsies generated from 75 resection specimens (30 FNHs, 15 hepatocellular adenomas, 15 hepatocellular carcinomas, and 15 non-lesional liver specimens). Pathologists were reasonably accurate (83.1%) in the diagnosis of FNH with haematoxylin and eosin alone. Ductular reaction and nodularity had the highest sensitivity for a diagnosis of FNH (88.1% and 82.2%, respectively), whereas central scar was the most specific feature (90.6%). The presence of two or more of the classic histological features had 89.6% sensitivity and 86.2% specificity for a diagnosis of FNH. Diagnostic accuracy was significantly higher with the addition of a GS stain. A map-like GS staining pattern was highly specific (99.3%) for FNH. However, GS staining was interpreted as non-map-like in 14.4% of reviews of true FNH cases, and overall interobserver agreement for interpretation of the GS staining pattern was only moderate (kappa = 0.42)., Conclusions: Pathologists are reasonably accurate in the diagnosis of FNH on virtual biopsies, and GS staining improves accuracy. However, a subset of FNH cases remain challenging. Steatosis and a pseudo-map-like GS staining pattern were associated with increased difficulty. Therefore, although a map-like GS staining pattern is useful for confirmation of a diagnosis, the lack of a map-like GS staining pattern on needle biopsy does not necessarily exclude a diagnosis of FNH., (© 2021 John Wiley & Sons Ltd.)

Content available: Author Interview and Audio Recording., (© 2021 by the American Association for the Study of Liver Diseases.)

Background/aims: Glycogen synthesis and storage are normal hepatocyte functions. However, glycogenosis, defined as excess hepatocyte glycogen visible by routine H&E light microscopy, has not been well characterized in nonalcoholic fatty liver disease (NAFLD)., Methods: Glycogenosis in NAFLD liver biopsies was graded as "none", "focal" (in <50% of hepatocytes), or "diffuse" (in ≥50% of hepatocytes). Clinical and pathological variables associated with glycogenosis were assessed. 2047 liver biopsies were prospectively analysed., Results: In adults and children, any glycogenosis was present in 54% of cases; diffuse glycogenosis was noted in approximately 1/3 of cases. On multiple logistic regression analysis, adults with glycogenosis tended to be older (P = .003), female (P = .04), have higher serum glucose (P = .01), and use insulin (P = .02). Adults tended to have lower steatosis scores (P = .006) and lower fibrosis stages (P = .005); however, unexpectedly, they also tended to have more hepatocyte injury including ballooning (P = .003). On multiple logistic regression analysis, paediatric patients with glycogenosis were more likely to be Hispanic (P = .03), have lower body weight (P = .002), elevated triglycerides (P = .001), and a higher fasting glucose (P = .007). Paediatric patients with glycogenosis also had less steatosis (P < .001) than those without., Conclusions: Glycogenosis is common in adult and paediatric NAFLD, and is associated with clinical features of insulin resistance. Glycogenosis is important to recognize histologically because it may be misinterpreted as ballooning, and when diffuse, confusion with glycogen storage disorders or glycogenic hepatopathy must be avoided. The newly observed dichotomous relationship between glycogenosis and increased liver cell injury but decreased steatosis and fibrosis requires further study., (© 2020 The Authors. Liver International published by John Wiley & Sons Ltd.)

Obesity is a global epidemic leading to increased mortality and susceptibility to comorbidities, with few viable therapeutic interventions. A hallmark of disease progression is the ectopic deposition of lipids in the form of lipid droplets in vital organs such as the liver. However, the mechanisms underlying the dynamic storage and processing of lipids in peripheral organs remain an outstanding question. Here, we show an unexpected function for the major cap-binding protein, eIF4E, in high-fat-diet-induced obesity. In response to lipid overload, select networks of proteins involved in fat deposition are altered in eIF4E-deficient mice. Specifically, distinct messenger RNAs involved in lipid metabolic processing and storage pathways are enhanced at the translation level by eIF4E. Failure to translationally upregulate these mRNAs results in increased fatty acid oxidation, which enhances energy expenditure. We further show that inhibition of eIF4E phosphorylation genetically-and by a potent clinical compound-restrains weight gain following intake of a high-fat diet. Together, our study uncovers translational control of lipid processing as a driver of high-fat-diet-induced weight gain and provides a pharmacological target to treat obesity.

The diagnosis of a large B-cell lymphoma and classic Hodgkin lymphoma (CHL) is often straightforward. However, in select circumstances, these simple diagnoses can be quite complex. In part, diagnostic difficulty may be due to uncertainty in the evaluation of morphologic and immunophenotypic features along a biologic continuum, or alternatively arise from uncertainty in predicting the behavior and outcomes of patients. Here, we systematically discuss and review areas of diagnostic difficulty in the diagnosis of large B-cell lymphomas (LBCL), classic Hodgkin lymphomas (CHL) and peripheral T-cell lymphomas (PTCL). We provide careful data-driven analyses and evidence-based approaches to help guide pathologists and clinicians. We discuss: 1) marginal zone lymphomas with increased large cells versus diffuse large B-cell lymphoma (DLBCL), 2) chronic lymphocytic leukemia with expanded proliferation centers versus diffuse large B-cell lymphoma (DLBCL), 3) chronic lymphocytic leukemia with Hodgkin/Reed-Sternberg-like cells versus CHL arising from chronic lymphocytic leukemia, 4) complex cases of follicular lymphoma versus DLBCL, 5) PTCL with large B-cell proliferations versus PTCL with LBCL, 6) PTCL with Hodgkin/Reed-Sternberg-like cells versus CHL, and finally 7) blastoid/pleomorphic mantle cell lymphoma versus DLBCL. Our evidence and data driven approach may serve as a useful diagnostic guide., Competing Interests: Declaration of competing interest None declared., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Aims: The aim of this study was to perform a comprehensive retrospective analysis of liver transplant biopsies with parenchymal rejection (PR) at our institution, including histological features, laboratory values and follow-up biopsies, and to compare PR with portal-based acute cellular rejection (ACR)., Methods and Results: Biopsies from 173 patients were evaluated (retrospective database search 1990-2017), including 49 isolated PR, 35 PR with portal ACR (PR/ACR), 34 mild ACR and 52 moderate ACR cases. The rise and fall of serum liver enzymes was calculated as a measure of acute liver injury and response to immunotherapy, respectively. Isolated PR was associated with delayed-onset acute rejection (P < 0.001), as well as younger age (P = 0.004), and showed a similar rise in liver enzymes to mild ACR. PR/ACR and moderate ACR showed the highest elevations in transaminases (P < 0.05). Isolated PR on an initial biopsy was associated with recurrent episodes of PR (P = 0.01), chronic ductopaenic rejection (P = 0.002) and chronic vascular rejection (P = 0.017). Immunohistochemistry for C4d was performed, and strong C4d staining of venules was only detected in one severe isolated PR case (one of three, 33%) and one moderate ACR case (one of 20, 5%)., Conclusions: Isolated PR represents a form of late acute rejection with distinct clinical and histological features. There is value in reporting PR in liver transplant biopsies to identify patients at higher risk of developing recurrent PR and chronic rejection. Standardisation of terminology and histological criteria of PR can help in uniform reporting and ensure appropriate management., (© 2019 John Wiley & Sons Ltd.)

Background: Polycystic ovary syndrome (PCOS) affects 10% of reproductive-aged women, and is marked by irregular menses and high androgens. PCOS is a known risk factor for imaging-confirmed steatosis, and we now aim to evaluate whether PCOS influences histologic severity of non-alcoholic fatty liver disease (NAFLD)., Methods: Retrospective study of women ages 18-45 years with biopsy-confirmed NAFLD between 2008 and 2019. Metabolic comorbidities were captured within 6 months of biopsy. Histologic features of non-alcoholic steatohepatitis (NASH) were independently evaluated by two pathologists blinded to PCOS status., Results: Among 102 women meeting study criteria, 36% (n = 37) had PCOS; median age was 35 years; 27% were white, 6% black, 19% Asian and 47% reported Hispanic ethnicity. Women with PCOS had higher LDL (122 vs 102 mg/dL, P = .05) and body mass index(BMI) (38 vs 33 kg/cm 2 , P < .01). NASH was present in 76% of women with PCOS vs 66% without PCOS (P = .3), and a higher proportion with PCOS had severe ballooning (32% vs 13%, P = .02), presence of any fibrosis (84% vs 66%, P = .06) and advanced fibrosis (16% vs 6%, P = .10). Adjusted for age and BMI, PCOS remained associated with severe hepatocyte ballooning (OR 3.4, 95% CI 1.1-10.6, P = .03) and advanced fibrosis (OR 7.1, 95% CI 1.3-39, P = .02). Among women with advanced fibrosis, median age was 5 years younger in those with as compared to those without PCOS (40 vs 45 years, P = .02)., Conclusion: Polycystic ovary syndrome is independently associated with more severe NASH, including advanced fibrosis. Hepatologists should routinely inquire about PCOS in reproductive-aged women with NAFLD, and evaluate for more severe liver disease in this population., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aims: The pathological features and diagnostic reliability of crypt cell atypia (CCA) arising in inflammatory bowel disease (IBD) and its clinical significance are unknown., Methods and Results: DNA flow cytometry (FCM) was performed on 14 colon biopsies of CCA from seven IBD patients (male-to-female ratio, 5:2; mean age, 53 years; mean IBD duration, 15 years) using paraffin-embedded tissue. Seven gastrointestinal pathologists were asked to diagnose each biopsy as negative for dysplasia (NEG), indefinite for dysplasia (IND), low-grade dysplasia (LGD) or high-grade dysplasia (HGD) by morphology alone, then again with knowledge of FCM results. Aneuploidy was detected in all 14 biopsies, and five of eight biopsies (63%) also showed strong and diffuse nuclear staining for p53 in the areas of CCA. Six (86%) patients developed HGD (n = 5) or adenocarcinoma (n = 1) in the same colonic segment where CCA had been diagnosed within a mean follow-up time of 27 months. No follow-up information was available in the remaining one patient. When diagnoses were grouped as NEG or 'atypical' (including IND, LGD or HGD), the overall agreement rate of 76% (kappa = 0.51) based on morphology alone improved to 90% (kappa = 0.81) with knowledge of FCM results. Even when categorised as NEG or dysplasia (LGD or HGD) with each of the IND diagnoses reclassified into three categories (NEG, LGD or HGD) based on the degree of suspicion for dysplasia, the overall agreement rate of 63% (kappa = 0.25) based on morphology alone improved to 73% (kappa = 0.46) with knowledge of FCM results. However, when grouped as NEG, LGD or HGD, the overall agreement rate was less than 40% (kappa < 0.09) regardless of knowledge of FCM results., Conclusions: The presence of aneuploidy, p53 positivity and development of HGD or adenocarcinoma on follow-up indicate that CCA likely represents a dysplastic lesion (at least LGD) and is a histological marker of neoplastic progression. Although the grading of CCA, largely based on cytological abnormalities, is subject to significant interobserver variability, CCA can be histologically identified and should lead to a recommendation of increased endoscopic surveillance, especially if aneuploidy is detected., (© 2019 John Wiley & Sons Ltd.)

Small nucleolar RNAs (snoRNAs) are a diverse group of non-coding RNAs that direct chemical modifications at specific residues on other RNA molecules, primarily on ribosomal RNA (rRNA). SnoRNAs are altered in several cancers; however, their role in cell homeostasis as well as in cellular transformation remains poorly explored. Here, we show that specific subsets of snoRNAs are differentially regulated during the earliest cellular response to oncogenic RAS G12V expression. We describe a novel function for one H/ACA snoRNA, SNORA24 , which guides two pseudouridine modifications within the small ribosomal subunit, in RAS-induced senescence in vivo. We find that in mouse models, loss of Snora24 cooperates with RAS G12V to promote the development of liver cancer that closely resembles human steatohepatitic hepatocellular carcinoma (HCC). From a clinical perspective, we further show that human HCCs with low SNORA24 expression display increased lipid content and are associated with poor patient survival. We next asked whether ribosomes lacking SNORA24 -guided pseudouridine modifications on 18S rRNA have alterations in their biophysical properties. Single-molecule Fluorescence Resonance Energy Transfer (FRET) analyses revealed that these ribosomes exhibit perturbations in aminoacyl-transfer RNA (aa-tRNA) selection and altered pre-translocation ribosome complex dynamics. Furthermore, we find that HCC cells lacking SNORA24 -guided pseudouridine modifications have increased translational miscoding and stop codon readthrough frequencies. These findings highlight a role for specific snoRNAs in safeguarding against oncogenic insult and demonstrate a functional link between H/ACA snoRNAs regulated by RAS and the biophysical properties of ribosomes in cancer., Competing Interests: MM, MH, TU, CF, XP, CJ, MC, BC, DQ, RK, JG, RG, SB, DR No competing interests declared, AC Current employee of Celgene Corporation, JL Current employee of Arbele Corporation, (© 2019, McMahon et al.)

Terminal deoxynucleotidyl transferase (TdT) is a nuclear enzyme restricted to precursor lymphoid cells and their malignant counterparts; immunohistochemical TdT labeling is helpful in recognition of lymphoblasts, which can resemble mature lymphocytes. The diagnosis of B-lymphoblastic leukemia/lymphoma (B-ALL) is occasionally first encountered on liver core biopsy, but TdT immunostain specificity for B-ALL is not clearly established in this setting, which can be problematic when only a few TdT-positive cells are identified. In this study, we evaluated the incidence and distribution of immature B lymphocytes coexpressing TdT and PAX-5, in pediatric and adult liver biopsies, to determine whether a normal complement of hepatic immature B cells can be detected, which must be recognized in a workup to exclude B-ALL. We selected 41 pediatric and adult liver biopsies with a significant portal and/or sinusoidal hematolymphoid infiltrate and performed immunohistochemical stains for TdT and PAX-5 to identify and categorize distribution of immature B cells. TdT-positive cells were detected in 40% of pediatric liver biopsies with a significant hematolymphoid infiltrate (4/10), which included all biopsies from neonates (and infants under 9 wk of age). In adults, immature B-cell infiltrates were less common (6%, 2/31). Dual immunostaining was performed on 2 cases of neonatal hepatitis, which documented B-cell lineage in at least a subset of TdT-positive cells and there was no colabeling with CD3. Immature B cells can be detected in liver biopsies in a variety of clinical settings, most commonly in children, and presence of a few TdT-positive cells cannot be considered entirely specific for involvement by B-ALL. Further workup for B-ALL can be warranted if there is more extensive multifocal portal and/or sinusoidal involvement by blasts with TdT labeling.

Idiopathic non-cirrhotic portal hypertension (INCPH) is a rare vascular liver disease that has attracted new interest in recent years. It is characterised by clinical signs of portal hypertension in the absence of cirrhosis or severe fibrosis and any known cause of portal hypertension. As much uncertainty exists about INCPH pathophysiology, and no definite diagnostic tests are available, liver biopsy is an essential tool for achieving a definite diagnosis. Unfortunately, the histological diagnosis of INCPH is not always straightforward, as the characteristic lesions are unevenly distributed, vary greatly in their severity, are often very subtle, and are not all necessarily present in a single case. Furthermore, specifically for the characteristic portal vessel changes observed in INCPH, the terminology and definition are ambiguous, which adds complexity to the already complex clinicopathological scenario. An international study group of liver pathologists and hepatologists pursued a consensus on nomenclature for the portal vascular lesions of INCPH. Such standardisation may assist pathologists in the recognition of such lesions, and will possibly facilitate further advancement in this field., (© 2018 John Wiley & Sons Ltd.)

Background & Aims: Cross-sectional studies of patients with nonalcoholic fatty liver disease (NAFLD) have reported a lower prevalence of severe disease among modest drinkers compared with nondrinkers. We collected data from adult participants in the Nonalcoholic Steatohepatitis (NASH) Clinical Research Network to evaluate the longitudinal association between modest use of alcohol and histology findings in patients with NAFLD, using paired liver biopsies collected more than 1 year apart., Methods: We studied NASH Clinical Research Network participants 21 years or older, not receiving pharmacologic therapy, from whom 2 or more liver biopsies and data on alcohol use within 2 years of the initial biopsy were available. Alcohol consumption was evaluated at study entry using the Alcohol Use Disorders Identification Test and Skinner Lifetime Drinking History questionnaires. At each follow-up visit participants were asked about alcohol use frequency, number of drinks on a typical day, and frequency of heavy drinking. The association between baseline drinking status and changes in fibrosis stage, NASH histology, and the NAFLD Activity Score and its individual components were evaluated by analysis of covariance. The association between change in drinking status and change in histology was evaluated using adjusted logistic regression., Results: Of 285 participants (82% white, 70% female, mean age, 47 y) meeting entry criteria, 168 (59%) were modest alcohol users (≤2 drinks/d) and the remaining 117 were abstinent. At baseline, a higher proportion of modest alcohol users were white (86% vs 76% nonwhite) (P = .04) and a lower proportion of modest alcohol users were diagnosed with definite NASH (57% vs 74% without NASH; P = .01). During a mean follow-up period of 47 months between biopsies, nondrinkers had a greater mean reduction in steatosis grade (reduction, 0.49) than modest drinkers (reduction, 0.30; P = .04) and a greater reduction in mean level of aspartate transaminase (reduction, 7 U/L vs an increase of 2 U/L in modest drinkers; P = .04). Modest drinkers had significantly lower odds of NASH resolution compared with nondrinkers (adjusted odds ratio, 0.32; 95% CI, 0.11-0.92; P = .04) on adjusted analysis., Conclusions: In a longitudinal analysis of liver biopsies from patients with NAFLD not receiving pharmacologic therapy, modest alcohol use was associated with less improvement in steatosis and level of aspartate transaminase, as well as lower odds of NASH resolution, compared with no use of alcohol., (Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Hepatic small vessel neoplasm (HSVN) is a recently described infiltrative vascular neoplasm of the liver, composed of small vessels. Although the infiltrative nature can mimic angiosarcoma, HSVN are thought to be benign or low-grade neoplasms because they lack cytologic atypia and increased proliferation. To characterize the molecular pathogenesis of HSVN, we performed both targeted panel sequencing and exome sequencing on 18 benign or low-grade vascular neoplasms in the liver including 8 HSVN, 6 classic cavernous hemangioma (CH), and 4 variant lesions (VL) with overlapping features between HSVN and CH. All 18 lesions had simple genomes without copy number alterations. In total, 75% (6/8) of HSVN demonstrated known activating hotspot mutations in GNAQ (2/8, p.Q209H) or GNA14 (4/8, p.Q205L), and the remaining 2 had the same missense mutation in GNAQ, p.G48L, which has not been previously described. 25% (1/4) of VL had a hotspot GNAQ p.Q209H mutation and another VL had a GNAQ p.G48L mutation. Known pathogenic mutations were not identified in any of the 6 CH. These data suggest that HSVN share a similar molecular biology to several other vascular lesions (congenital hemangioma, tufted angioma, anastomosing hemangioma, lobular capillary hemangioma, and kaposiform hemangioendothelioma) recently reported to have GNAQ, GNA11, or GNA14 mutations.

Aims: Serrated lesions (SLs), including sessile serrated adenoma (SSA) and traditional serrated adenoma (TSA), are important premalignant lesions for colorectal cancer (CRC). Although a small subset of SLs are known to harbour TP53 mutations and Wnt/β-catenin pathway activation, suggesting that they may develop dysplasia or CRC via a 'chromosomal instability (CIN)-like' pathway, it is unclear if aneuploidy (characteristic of conventional adenoma) ever develops in SLs and is associated with development of dysplasia or CRC, in this context., Methods and Results: DNA flow cytometry was performed on 31 inflammatory bowel disease (IBD)-associated SLs without dysplasia [including 10 non-targeted 'serrated epithelial change' (SEC), 14 SSAs and seven hyperplastic polyps (HPs)] as well as 48 dysplastic SSAs and TSAs. One (10%) of 10 SEC cases demonstrated aneuploidy and subsequently developed high-grade dysplasia (HGD) within 4 months, whereas the remaining SEC cases showed normal DNA content without evidence of dysplasia or CRC on follow-up. One (3.3%) of 30 TSAs without HGD and two (66.7%) of three TSAs with HGD also showed aneuploidy, but no patient developed CRC. By contrast, all SSAs (with or without dysplasia) and HPs showed normal DNA content, but four SSA cases still developed dysplasia or CRC on follow-up., Conclusions: Unlike SSAs and HPs, a small subset of SEC and TSA cases demonstrated aneuploidy, suggesting that they can develop neoplasia via the CIN pathway. DNA content analysis of a larger number of SEC cases, with adequate follow-up, may allow for a more precise determination of aneuploidy incidence and neoplasia risk., (© 2018 John Wiley & Sons Ltd.)

Eligibility for liver transplant is most commonly decided by measuring tumor size and number on radiographic imaging. However, this method often underestimates the extent of disease. Evaluation of tumor histology has been shown to improve risk stratification when compared with imaging-based transplant criteria, but the World Health Organization (WHO) guidelines for grading hepatocellular carcinoma (HCC) are imprecise and require subjective interpretation by the pathologist. We performed a retrospective analysis of 190 explanted livers containing HCC and correlated histologic features with posttransplant recurrence to formulate a three-tiered, point-based scoring system that categorizes tumors as having a low, intermediate, or high risk of recurrence. Our Recurrence Risk Assessment Score (RRAS) evaluates tumor architecture and specific cytologic features-nuclear pleomorphism, cytoplasmic amphophilia, and nuclear-to-cytoplasmic ratio-showing superior stratification of HCC recurrence risk compared with imaging criteria and grade assigned by WHO methodology. Stratifying tumors using RRAS criteria, the rate of recurrence after transplant was 0% among low-risk tumors (compared with 3% of well-differentiated tumors), 12% among intermediate-risk tumors (compared with 15% of moderately differentiated tumors), and 54% among high-risk tumors (compared with 29% of poorly differentiated tumors). Receiver operating characteristic analysis shows significantly improved performance of RRAS criteria in predicting HCC recurrence compared with WHO grade (area under curve of 0.841 and 0.671, respectively; P=0.0061). Our results indicate that evaluation of tumor histology offers superior prediction of recurrence risk following liver transplantation compared with radiographic criteria, and that the RRAS system better stratifies recurrence risk compared with HCC grading by WHO methodology.

Introduction: 'Acute-on-Chronic-Liver Failure (ACLF)' entered hepatology practice by the end of the 20th century. Although we lack precise and universally agreed definitions, acute decompensation of chronic liver disease with jaundice and deranged clotting, multi-organ failure and high, short-term mortality are hallmarks of the syndrome. Timely recognition and and treatment, including urgent liver transplantation, may save the life of certain patients. The diagnosis and management are mostly based on clinical features, but some have suggested to incorporate histopathology (liver biopsy). This may add to the differentiation between acute and chronic disease, primary and concomitant etiologies, and identify prognostic determinants. Areas covered: A review of the literature on ACLF and the outcome of the discussions at a topical international meeting on specific histopathological aspects of diagnosis and prognosis of the syndrome. Expert commentary: There is a lack of standardized descriptions of histopathological features and there is limited prospective experience with the role of pathology of ACLF. It is important for the clinical hepatologist to understand the potential and limitations of (transjugular) liver biopsy in ACLF and for the pathologist to help address the clinical question and recognise the histopathological features that help to characterize ACLF, both in terms of diagnosis and prognosis.

Systemic hematopoietic disorders may present on liver biopsy, and rare cases of primary hepatic lymphoma (PHL) may be encountered. Hepatopathologists must be familiar with the full spectrum of hematopoietic disorders involving the liver and be prepared to exclude benign mimics. PHL, which is confined to the liver without extrahepatic involvement, can present as solitary or multiple nodules, raising consideration for carcinoma on imaging, or may mimic benign inflammatory conditions, posing a diagnostic challenge. This article describes clinical, morphologic, and immunophenotypic features of some of the most common hematopoietic neoplasms involving the liver, along with differential diagnosis and recommended ancillary testing., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Aims: There is limited information regarding the clinicopathological and immunohistochemical characteristics of gastric pyloric gland adenomas (PGAs)., Methods and Results: Sixty-seven cases of gastric PGA from 57 patients were analysed. PGAs occurred with similar frequency in men and women (47.4 and 52.6%, respectively), with a mean age of 66 years. Most presented in the gastric body/fundus (67.2%). Fifteen cases (22.4%) developed against a background of autoimmune gastritis (AIG), whereas normal mucosa was seen in 35.8%. Only 16.4% (11 cases) developed in patients with a genetic predisposition, most commonly familial adenomatous polyposis. Low-grade lesions had a mean size of 1.5 cm, while PGAs with high-grade dysplasia (HGD) or adenocarcinoma had a mean size of 3.5 cm (P < 0.001) and more commonly showed tubulovillous architecture (50.0 versus 25.6% in low-grade dysplasia; P = 0.040). Most PGAs (61.2%) co-expressed mucin (MUC)5AC and MUC6 (mixed type), which was associated significantly with HGD or adenocarcinoma (P = 0.013). AIG was also associated with HGD (P = 0.027), but genetic predisposition did not correlate with the grade of dysplasia (P = 0.793). The recurrence rate of PGA was similar for high- (11.8%) and low-grade lesions (7.4%) (P = 0.624)., Conclusions: The risk of HGD increases with the size of PGA, tubulovillous architecture and the presence of AIG as well as mixed immunophenotype. As the overall local recurrence rate is less than 10%, PGAs may be treated conservatively, but they should be excised completely if possible, particularly if they are large or show high-grade features., (© 2017 John Wiley & Sons Ltd.)

Li-Fraumeni syndrome (LFS) is a rare cancer predisposition syndrome inherited in an autosomal dominant fashion that involves a germline mutation of tumor protein 53 (TP53). With the advent of more accessible and accurate genetic testing methods, along with more widespread knowledge of LFS, asymptomatic carriers can now be more easily identified. No general surveillance protocols were previously recommended other than routine physical exams and breast and colon cancer screening at younger ages, primarily due to questions involving efficacy, cost, and clinical benefits. With more data now available to support the implementation of a surveillance protocol for cancer predisposition syndromes such as LFS, preventative screening has become a national standard of care. However, as surveillance becomes more integrated into patient care, the benefits and risks must be further evaluated. We briefly describe our institutional experience with surveillance screening in LFS and describe two patients in depth where surveillance imaging brought to light false positives that led to increased utilization of resources and concern for new malignancy. Though the benefits of surveillance are clear, it is important to understand the potential for false positives involved with instituting this practice. Continued research of this topic is thus warranted, perhaps with larger prospective studies, to better capture the survival benefits of patients undergoing surveillance screening and more comprehensively understand the incidence of false positives., Competing Interests: The authors have declared that no competing interests exist.

This study presents the radiological findings of seven cases of solitary fibrous tumor (SFT) in the abdomen and pelvis. A retrospective search of the pathology database at our institution was performed to identify cases of SFT in the abdomen and pelvis. After identifying seven cases, cross-sectional imaging was reviewed and characterized. We conclude that SFTs in the abdomen and pelvis should be considered with well-defined, circular, hypervascular masses. Pelvic SFTs should be considered with homogenous, avidly enhancing masses. Embolization of feeding arteries can allow safe surgical resection or biopsy, but embolization appears to not offer a definitive therapy., (Copyright © 2017 Elsevier Inc. All rights reserved.)

It has been reported that mitochondria can contain up to 12 enzymatic sources of reactive oxygen species (ROS). A majority of these sites include flavin-dependent respiratory complexes and dehydrogenases that produce a mixture of superoxide (O2 ●- ) and hydrogen peroxide (H2O2). Accurate quantification of the ROS-producing potential of individual sites in isolated mitochondria can be challenging due to the presence of antioxidant defense systems and side reactions that also form O2 ●- /H2O2. Use of nonspecific inhibitors that can disrupt mitochondrial bioenergetics can also compromise measurements by altering ROS release from other sites of production. Here, we present an easy method for the simultaneous measurement of H2O2 release and nicotinamide adenine dinucleotide (NADH) production by purified flavin-linked dehydrogenases. For our purposes here, we have used purified pyruvate dehydrogenase complex (PDHC) and α-ketoglutarate dehydrogenase complex (KGDHC) of porcine heart origin as examples. This method allows for an accurate measure of native H2O2 release rates by individual sites of production by eliminating other potential sources of ROS and antioxidant systems. In addition, this method allows for a direct comparison of the relationship between H2O2 release and enzyme activity and the screening of the effectiveness and selectivity of inhibitors for ROS production. Overall, this approach can allow for the in-depth assessment of native rates of ROS release for individual enzymes prior to conducting more sophisticated experiments with isolated mitochondria or permeabilized muscle fiber.

Protein S-glutathionylation is a reversible redox modification that regulates mitochondrial metabolism and reactive oxygen species (ROS) production in liver and cardiac tissue. However, whether or not it controls ROS release from skeletal muscle mitochondria has not been explored. In the present study, we examined if chemically-induced protein S-glutathionylation could alter superoxide (O2●-)/hydrogen peroxide (H2O2) release from isolated muscle mitochondria. Disulfiram, a powerful chemical S-glutathionylation catalyst, was used to S-glutathionylate mitochondrial proteins and ascertain if it can alter ROS production. It was found that O2●-/H2O2 release rates from permeabilized muscle mitochondria decreased with increasing doses of disulfiram (100-500 μM). This effect was highest in mitochondria oxidizing succinate or palmitoyl-carnitine, where a ~80-90% decrease in the rate of ROS release was observed. Similar effects were detected in intact mitochondria respiring under state 4 conditions. Incubation of disulfiram-treated mitochondria with DTT (2 mM) restored ROS release confirming that these effects were associated with protein S-glutathionylation. Disulfiram treatment also inhibited phosphorylating and proton leak-dependent respiration. Radiolabelled substrate uptake experiments demonstrated that disulfiram inhibited pyruvate import but had no effect on carnitine uptake. Immunoblot analysis of complex I revealed that it contained several protein S-glutathionylation targets including NDUSF1, a subunit required for NADH oxidation. Taken together, these results demonstrate that O2●-/H2O2 release from muscle mitochondria can be altered by protein S-glutathionylation. We attribute these changes to the protein S-glutathionylation complex I and inhibition of mitochondrial pyruvate carrier.

Fibrolamellar carcinoma has a distinctive morphology and immunophenotype, including cytokeratin 7 and CD68 co-expression. Despite the distinct findings, accurate diagnosis of fibrolamellar carcinoma continues to be a challenge. Recently, fibrolamellar carcinomas were found to harbor a characteristic somatic gene fusion, DNAJB1-PRKACA. A break-apart fluorescence in situ hybridization (FISH) assay was designed to detect this fusion event and to examine its diagnostic performance in a large, multicenter, multinational study. Cases initially classified as fibrolamellar carcinoma based on histological features were reviewed from 124 patients. Upon central review, 104 of the 124 cases were classified histologically as typical of fibrolamellar carcinoma, 12 cases as 'possible fibrolamellar carcinoma' and 8 cases as 'unlikely to be fibrolamellar carcinoma'. PRKACA FISH was positive for rearrangement in 102 of 103 (99%) typical fibrolamellar carcinomas, 9 of 12 'possible fibrolamellar carcinomas' and 0 of 8 cases 'unlikely to be fibrolamellar carcinomas'. Within the morphologically typical group of fibrolamellar carcinomas, two tumors with unusual FISH patterns were also identified. Both cases had the fusion gene DNAJB1-PRKACA, but one also had amplification of the fusion gene and one had heterozygous deletion of the normal PRKACA locus. In addition, 88 conventional hepatocellular carcinomas were evaluated with PRKACA FISH and all were negative. These findings demonstrate that FISH for the PRKACA rearrangement is a clinically useful tool to confirm the diagnosis of fibrolamellar carcinoma, with high sensitivity and specificity. A diagnosis of fibrolamellar carcinoma is more accurate when based on morphology plus confirmatory testing than when based on morphology alone.

Most prior studies of primary diagnosis in surgical pathology using whole slide imaging (WSI) versus microscopy have focused on specific organ systems or included relatively few cases. The objective of this study was to demonstrate that WSI is noninferior to microscopy for primary diagnosis in surgical pathology. A blinded randomized noninferiority study was conducted across the entire range of surgical pathology cases (biopsies and resections, including hematoxylin and eosin, immunohistochemistry, and special stains) from 4 institutions using the original sign-out diagnosis (baseline diagnosis) as the reference standard. Cases were scanned, converted to WSI and randomized. Sixteen pathologists interpreted cases by microscopy or WSI, followed by a wash-out period of ≥4 weeks, after which cases were read by the same observers using the other modality. Major discordances were identified by an adjudication panel, and the differences between major discordance rates for both microscopy (against the reference standard) and WSI (against the reference standard) were calculated. A total of 1992 cases were included, resulting in 15,925 reads. The major discordance rate with the reference standard diagnosis was 4.9% for WSI and 4.6% for microscopy. The difference between major discordance rates for microscopy and WSI was 0.4% (95% confidence interval, -0.30% to 1.01%). The difference in major discordance rates for WSI and microscopy was highest in endocrine pathology (1.8%), neoplastic kidney pathology (1.5%), urinary bladder pathology (1.3%), and gynecologic pathology (1.2%). Detailed analysis of these cases revealed no instances where interpretation by WSI was consistently inaccurate compared with microscopy for multiple observers. We conclude that WSI is noninferior to microscopy for primary diagnosis in surgical pathology, including biopsies and resections stained with hematoxylin and eosin, immunohistochemistry and special stains. This conclusion is valid across a wide variety of organ systems and specimen types.

Background & Aims: Drug repositioning offers a shorter approval process than new drug development. We therefore searched large public datasets of drug-induced gene expression signatures to identify agents that might be effective against hepatocellular carcinoma (HCC)., Methods: We searched public databases of messenger RNA expression patterns reported from HCC specimens from patients, HCC cell lines, and cells exposed to various drugs. We identified drugs that might specifically increase expression of genes that are down-regulated in HCCs and reduce expression of genes up-regulated in HCCs using a nonparametric, rank-based pattern-matching strategy based on the Kolmogorov-Smirnov statistic. We evaluated the anti-tumor activity of niclosamide and its ethanolamine salt (NEN) in HCC cell lines (HepG2, Huh7, Hep3B, Hep40, and PLC/PRF/5), primary human hepatocytes, and 2 mouse models of HCC. In one model of HCC, liver tumor development was induced by hydrodynamic delivery of a sleeping beauty transposon expressing an activated form of Ras (v12) and truncated β-catenin (N90). In another mouse model, patient-derived xenografts were established by implanting HCC cells from patients into livers of immunocompromised mice. Tumor growth was monitored by bioluminescence imaging. Tumor-bearing mice were fed a regular chow diet or a chow diet containing niclosamide or NEN. In a separate experiment using patient-derived xenografts, tumor-bearing mice were given sorafenib (the standard of care for patients with advanced HCC), NEN, or niclosamide alone; a combination of sorafenib and NEN; or a combination sorafenib and niclosamide in their drinking water, or regular water (control), and tumor growth was monitored., Results: Based on gene expression signatures, we identified 3 anthelmintics that significantly altered the expression of genes that are up- or down-regulated in HCCs. Niclosamide and NEN specifically reduced the viability of HCC cells: the agents were at least 7-fold more cytotoxic to HCCs than primary hepatocytes. Oral administration of NEN to mice significantly slowed growth of genetically induced liver tumors and patient-derived xenografts, whereas niclosamide did not, coinciding with the observed greater bioavailability of NEN compared with niclosamide. The combination of NEN and sorafenib was more effective at slowing growth of patient-derived xenografts than either agent alone. In HepG2 cells and in patient-derived xenografts, administration of niclosamide or NEN increased expression of 20 genes down-regulated in HCC and reduced expression of 29 genes up-regulated in the 274-gene HCC signature. Administration of NEN to mice with patient-derived xenografts reduced expression of proteins in the Wnt-β-catenin, signal transducer and activator of transcription 3, AKT-mechanistic target of rapamycin, epidermal growth factor receptor-Ras-Raf signaling pathways. Using immunoprecipitation assays, we found NEN to bind cell division cycle 37 protein and disrupt its interaction with heat shock protein 90., Conclusions: In a bioinformatics search for agents that alter the HCC-specific gene expression pattern, we identified the anthelmintic niclosamide as a potential anti-tumor agent. Its ethanolamine salt, with greater bioavailability, was more effective than niclosamide at slowing the growth of genetically induced liver tumors and patient-derived xenografts in mice. Both agents disrupted interaction between cell division cycle 37 and heat shock protein 90 in HCC cells, with concomitant inhibition of their downstream signaling pathways. NEN might be effective for treatment of patients with HCC., (Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.)

While non-alcoholic steatohepatitis is a slowly progressive disease, patients may rarely present in acute liver failure. We describe six patients who developed severe hepatic dysfunction following rapid weight loss or malnutrition. Rapid weight loss (18 to 91 kg) occurred after Roux-en-Y gastric bypass in four patients and starvation-like dieting or hypoalbuminemia was noted in two patients. Four patients either died or received an urgent liver transplant. Pathologic findings were characterized by advanced alcoholic steatohepatitis-like features, including extensive/circumferential centrizonal pericellular fibrosis, central scar with perivenular sclerosis/veno-occlusion with superimposed hepatocellular dropout, abundant/prominent hepatocellular balloons, and numerous Mallory-Denk bodies, but there was no history of excess alcohol consumption. This study characterizes clinicopathologic features of aggressive non-alcoholic steatohepatitis following rapid weight loss or malnutrition, which should be included in the differential diagnosis with alcohol when a patient is considered for liver transplantation. The mechanism of liver injury in aggressive steatohepatitis is unknown, but rapid fat mobilization in obese patients may potentially cause oxidative stress to the liver and further study is needed to determine if there is a genetic predisposition to this form of injury and if antioxidants may protect the liver during rapid weight loss/malnutrition.