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Nonalcoholic fatty liver disease (NAFLD) and impaired glycemic control are closely linked; however, the pathophysiological mechanisms underpinning this bidirectional relationship remain unresolved. The high secretory capacity of the liver and impairments in protein secretion in NAFLD suggest that endocrine changes in the liver are likely to contribute to glycemic defects. We identify hexosaminidase A (HEXA) as an NAFLD-induced hepatokine in both mice and humans. HEXA regulates sphingolipid metabolism, converting GM2 to GM3 gangliosides-sphingolipids that are primarily localized to cell-surface lipid rafts. Using recombinant murine HEXA protein, an enzymatically inactive HEXA(R178H) mutant, or adeno-associated virus vectors to induce hepatocyte-specific overexpression of HEXA, we show that HEXA improves blood glucose control by increasing skeletal muscle glucose uptake in mouse models of insulin resistance and type 2 diabetes, with these effects being dependent on HEXA's enzymatic action. Mechanistically, HEXA remodels muscle lipid raft ganglioside composition, thereby increasing IGF-1 signaling and GLUT4 localization to the cell surface. Disrupting lipid rafts reverses these HEXA-mediated effects. In this study, we identify a pathway for intertissue communication between liver and skeletal muscle in the regulation of systemic glycemic control., (© 2023 by the American Diabetes Association.)

Objective: Liver biopsy is still needed for fibrosis staging in many patients with non-alcoholic fatty liver disease. The aims of this study were to evaluate the individual diagnostic performance of liver stiffness measurement by vibration controlled transient elastography (LSM-VCTE), Fibrosis-4 Index (FIB-4) and NAFLD (non-alcoholic fatty liver disease) Fibrosis Score (NFS) and to derive diagnostic strategies that could reduce the need for liver biopsies., Design: Individual patient data meta-analysis of studies evaluating LSM-VCTE against liver histology was conducted. FIB-4 and NFS were computed where possible. Sensitivity, specificity and area under the receiver operating curve (AUROC) were calculated. Biomarkers were assessed individually and in sequential combinations., Results: Data were included from 37 primary studies (n=5735; 45% women; median age: 54 years; median body mass index: 30 kg/m 2 ; 33% had type 2 diabetes; 30% had advanced fibrosis). AUROCs of individual LSM-VCTE, FIB-4 and NFS for advanced fibrosis were 0.85, 0.76 and 0.73. Sequential combination of FIB-4 cut-offs (<1.3; ≥2.67) followed by LSM-VCTE cut-offs (<8.0; ≥10.0 kPa) to rule-in or rule-out advanced fibrosis had sensitivity and specificity (95% CI) of 66% (63-68) and 86% (84-87) with 33% needing a biopsy to establish a final diagnosis. FIB-4 cut-offs (<1.3; ≥3.48) followed by LSM cut-offs (<8.0; ≥20.0 kPa) to rule out advanced fibrosis or rule in cirrhosis had a sensitivity of 38% (37-39) and specificity of 90% (89-91) with 19% needing biopsy., Conclusion: Sequential combinations of markers with a lower cut-off to rule-out advanced fibrosis and a higher cut-off to rule-in cirrhosis can reduce the need for liver biopsies., Competing Interests: Competing interests: AG reports personal fees from AbbVie, personal fees from Alexion, personal fees from Bayer, personal fees from BMS, personal fees from CSL Behring, personal fees from Gilead, grants and personal fees from Intercept, personal fees from Ipsen, personal fees from Merz, grants and personal fees from Novartis, personal fees from Pfizer, personal fees from Sanofi-Aventis, personal fees from Sequana, grants and personal fees from Falk, personal fees from MSD, during the conduct of the study. ANAJ reports other from Perspectum, during the conduct of the study. CF reports other from Echosens, during the conduct of the study. JFC reports personal fees from AstraZeneca, personal fees from Novo Nordisk, personal fees from Intercept, personal fees from Alnylam, during the conduct of the study. JB reports other from Pfizer, during the conduct of the study. JMS reports personal fees from BMS, personal fees from Boehringer Ingelheim, personal fees from Echosens, personal fees from Genfit, personal fees from Gilead Sciences, personal fees from Intercept Pharmaceuticals, personal fees from Madrigal, personal fees from Novartis, personal fees from Pfizer, personal fees from Roche, personal fees from Sanofi, personal fees from Falk Foundation, personal fees from MSD, grants from Gilead Sciences, during the conduct of the study. JW reports grants from Echosens, during the conduct of the study. Dr. Pavlides reports other from Perspectum, during the conduct of the study. MT reports personal fees from Bristol-Myers Squibb, personal fees from Falk Foundation, personal fees from Gilead, personal fees from Intercept, personal fees from Merck Sharp & Dohme, personal fees from Albireo, personal fees from Boehringer Ingelheim, personal fees from BiomX, personal fees from Falk Pharma GmbH, personal fees from GENFIT, personal fees from Jannsen, personal fees from Novartis, personal fees from Phenex, personal fees from Regulus and Shire, grants from AbbVie, grants from Falk, grants from Gilead, grants from Intercept, grants from Albireo, grants from CymaBay, grants from Merck Sharp & Dohme, grants from Takeda, during the conduct of the study; in addition, MT has a patent norUDCA issued. PNN reports personal fees from Bristol-Myers Squibb, personal fees from Gilead, personal fees from Boehringer Ingelheim, personal fees from Pfizer, personal fees from Novo Nordisk, personal fees from Poxel, grants from Pharmaxis, grants from Boehringer Ingelheim, grants from Echosens, grants from Novo Nordisk, during the conduct of the study. QMA reports grants from AbbVie, grants and personal fees from Allergan/Tobira, grants from AstraZeneca, grants from GlaxoSmithKline, grants from Glympse Bio, grants and personal fees from Novartis Pharma, grants and personal fees from Pfizer, grants from Vertex, personal fees from Abbott Laboratories, personal fees from Acuitas Medical, personal fees from Blade, personal fees from BNN Cardio, personal fees from Cirius, personal fees from CymaBay, personal fees from EcoR1, personal fees from Eli Lilly, personal fees from Galmed, personal fees from Genfit, personal fees from Gilead, personal fees from Grunthal, personal fees from HistoIndex, personal fees from Indalo, personal fees from Imperial Innovations, personal fees from Intercept Pharma Europe, personal fees from Inventiva, personal fees from IQVIA, personal fees from Janssen, personal fees from Kenes, personal fees from Madrigal, personal fees from MedImmune, personal fees from Metacrine, personal fees from NewGene, personal fees from NGMBio, personal fees from North Sea Therapeutics, personal fees from Novo Nordisk, personal fees from Poxel, personal fees from ProSciento, personal fees from Raptor Pharma, personal fees from Servier, personal fees from Viking Therapeutics, personal fees from Abbott Laboratories, personal fees from BMS, personal fees from Clinical Care Options, personal fees from Falk, personal fees from Fishawack, personal fees from Integritas Communications, personal fees from MedScape, other from IMI2 LITMUS consortium, during the conduct of the study. SH reports grants and personal fees from Akero, grants and personal fees from Axcella, grants and personal fees from Cirius, grants and personal fees from CiVi Biopharma, grants and personal fees from CymaBay, grants and personal fees from Galectin, grants from Galmed, grants and personal fees from Genfit, grants and personal fees from Gilead Sciences, grants and personal fees from Hepion Pharmaceuticals, grants and personal fees from Hightide Therapeutics, grants and personal fees from Intercept, grants and personal fees from Madrigal, grants and personal fees from Metacrine, grants and personal fees from NGM Bio, grants and personal fees from North Sea Therapeutics, grants and personal fees from Novartis, grants and personal fees from Novo Nordisk, grants and personal fees from Poxel, grants and personal fees from Sagimet, grants and personal fees from Viking, personal fees from Altimmune, personal fees from Alentis, personal fees from Arrowhead, personal fees from Canfite, personal fees from Echosens, personal fees from Enyo, personal fees from Fibronostics, personal fees from Foresite Labs, personal fees from Fortress Biotech, personal fees from HistoIndex, personal fees from Kowa, personal fees from Prometic, personal fees from Ridgeline, personal fees from Terns, during the conduct of the study. SM reports personal fees from Echosens, during the conduct of the study. SN reports other from Perspectum, during the conduct of the study. SP reports personal fees from AbbVie, personal fees from Gilead, personal fees from Intercept, personal fees from Pfizer, during the conduct of the study. TK reports grants from Echosens, during the conduct of the study. TT reports other from Pfizer, during the conduct of the study. VdL reports personal fees from Bristol-Myers Squibb, personal fees from Gilead Sciences, personal fees from AbbVie, personal fees from Pfizer, personal fees from Echosens, personal fees from Intercept Pharmaceuticals, personal fees from MSD, personal fees from Myr-Pharma, personal fees from Supersonic Imagine, personal fees from Tillotts, during the conduct of the study. Dr. Wong reports personal fees from AbbVie, personal fees from 3V-BIO, personal fees from Allergan, personal fees from Boehringer Ingelheim, personal fees from Center for Outcomes Research in Liver Diseases, grants and personal fees from Gilead, personal fees from Intercept, personal fees from Echosens, personal fees from Hanmi Pharmaceutical, personal fees from Novartis, personal fees from Pfizer, personal fees from Merck, personal fees from Novo Nordisk, personal fees from Perspectum, personal fees from ProSciento, personal fees from Sagimet Biosciences, personal fees from TARGET PharmaSolutions, personal fees from Terns, personal fees from BMS, during the conduct of the study. WK reports personal fees from Samil, personal fees from Boehringer Ingelheim, personal fees from Ildong, personal fees from LG Chemistry, personal fees from Gilead Sciences, personal fees from HK inno.N, personal fees from GreenCross, personal fees from Bukwang, personal fees from Standigm, personal fees from PharmaKing, personal fees from KOBIOLABS, personal fees from Eisai, personal fees from Zydus, personal fees from Novo Nordisk, grants from Gilead, grants from Ildong, grants from GreenCross, grants from Bukwang, grants from PharmaKing, grants from Roche, grants from Galmed, grants from Novartis, grants from Pfizer, grants from Springbank, grants from Altimmune, grants from MSD, grants from BMS, grants from Dicerna, grants from Enyo, grants from Hitachi-Aloka, other from KOBIOLABS, other from Lepidyne, during the conduct of the study. YY reports grants from Biocodes, grants and personal fees from Gilead Sciences, personal fees from Bilim Pharmaceuticals, personal fees from Pharmactive Pharmaceutical, personal fees from Sanovel Pharmaceuticals, personal fees from Galmed, personal fees from Zydus, personal fees from Novo Nordisk, during the conduct of the study. MP, ANAJ and SN are shareholders of Perspectum, Oxford, UK. CF is employed by Echosens, France. MT received speaker fees from Bristol-Myers Squibb (BMS), Falk Foundation, Gilead, Intercept and Merck Sharp & Dohme (MSD); advisory board fees from Albireo, Boehringer Ingelheim, BiomX, Falk Pharma GmbH, GENFIT, Gilead, Intercept, Jannsen, MSD, Novartis, Phenex, Regulus and Shire; travel grants from AbbVie, Falk, Gilead, and Intercept; and research grants from Albireo, CymaBay, Falk, Gilead, Intercept, MSD, and Takeda. He is also coinventor of patents on the medical use of norUDCA filed by the Medical University of Graz. SP was speaker and/or Advisor for AbbVie, Gilead, Intercept and Pfizer. PNN received grant and research support from Pharmaxis, Boehringer Ingelheim, Echosens and Novo Nordisk and consulting fees from BMS, Boehringer Ingelheim, Gilead, Novo Nordisk, Pfizer, and Poxel on behalf of the University of Birmingham. VL reports consultancy for AbbVie, BMS, Echosens, Gilead Sciences, Intercept Pharmaceuticals, MSD, Myr-Pharma, Pfizer, Supersonic Imagine and Tillotts. SM received honorarium fees from Echosens. JFC received consultancy, advisory board, and speaker fees from Astra Zeneca, NovoNordisk, Intercept and Alnylam. JMS reports consultancy for BMS, Boehringer Ingelheim, Echosens, Genfit, Gilead Sciences, Intercept Pharmaceuticals, Madrigal, Novartis, Pfizer, Roche, Sanofi; received research funding from Gilead Sciences and was on the speakers bureau for Falk Foundation MSD Sharp & Dohme GmbH. WK has served as a speaker and consultant of Gilead, Boehringer-Ingelheim, Samil, Ildong, LG Chemistry, HK inno.N, GreenCross, Bukwang, Standigm, PharmaKing, KOBIOLABS, Eisai, Zydus, and Novonordisk, received grants from Gilead, Ildong, GreenCross, Bukwang, Pharmaking, Roche, Galmed, Novartis, Pfizer, Springbank, Altimmune, MSD, BMS, Dicerna, Enyo, and Hitachi-Aloka, and owns stocks in KOBIOLABS and Lepidyne. TK and JW received unrestricted research grants from Echosens, Paris France. TK participated in a clinical advisory board meeting. YY received research grant from Biocodex, Gilead Sciences, speaker fees for Gilead Sciences, Bilim Pharmaceuticals, Pharmactive Pharmaceutical, Sanovel Pharmaceuticals, and served as advisory board member for Galmed, Zydus, NovoNordisk. AG reports consultancy for AbbVie, Alexion, Bayer, BMS, CSL Behring, Gilead, Intercept, Ipsen, Merz, Novartis, Pfizer, Sanofi-Aventis, Sequana; received research funding from Intercept, Falk, Novartis and was on the speakers bureau for AbbVie, Alexion, BMS, CSL Behring, Falk Foundation, Gilead, Intercept, MSD, Merz, Novartis, Sequana. VWSW has served as a consultant or advisory board member for 3V-BIO, AbbVie, Allergan, Boehringer Ingelheim, Center for Outcomes Research in Liver Diseases, Echosens, Gilead Sciences, Hanmi Pharmaceutical, Intercept, Merck, Novartis, Novo Nordisk, Perspectum Diagnostics, Pfizer, ProSciento, Sagimet Biosciences, TARGET PharmaSolutions, and Terns; and a speaker for AbbVie, Bristol-Myers Squibb, Echosens, and Gilead Sciences. He has also received a research grant from Gilead Sciences for fatty liver research. QMA is coordinator of the IMI2 LITMUS consortium and he reports research grant funding from Abbvie, Allergan/Tobira, AstraZeneca, GlaxoSmithKline, Glympse Bio, Novartis Pharma AG, Pfizer Ltd., Vertex; consultancy on behalf of Newcastle University for Abbott Laboratories, Acuitas Medical, Allergan/Tobira, Blade, BNN Cardio, Cirius, CymaBay, EcoR1, E3Bio, Eli Lilly & Company Ltd., Galmed, Genfit SA, Gilead, Grunthal, HistoIndex, Indalo, Imperial Innovations, Intercept Pharma Europe Ltd., Inventiva, IQVIA, Janssen, Kenes, Madrigal, MedImmune, Metacrine, NewGene, NGMBio, North Sea Therapeutics, Novartis, Novo Nordisk A/S, Pfizer Ltd., Poxel, ProSciento, Raptor Pharma, Servier, Viking Therapeutics; and speaker fees from Abbott Laboratories, Allergan/Tobira, BMS, Clinical Care Options, Falk, Fishawack, Genfit SA, Gilead, Integritas Communications, MedScape. SAH has research grants from Akero, Axcella, Cirius, CiVi Biopharma, Cymabay, Galectin, Galmed, Genfit, Gilead Sciences, Hepion Pharmaceuticals, Hightide Therapeutics, Intercept, Madrigal, Metacrine, NGM Bio, Northsea Therapeutics, Novartis, Novo Nordisk, Poxel, Sagimet, Viking. He has received consulting fees from Akero, Altimmune, Alentis, Arrowhead, Axcella, Canfite, Cirius, CiVi, Cymabay, Echosens, Enyo, Fibronostics, Foresite Labs, Fortress Biotech, Galectin, Genfit, Gilead Sciences, Hepion, HIghtide, HistoIndex, Intercept, Kowa, Madrigal, Metacrine, NGM, Northsea, Novartis, Novo Nordisk, Poxel, Prometic, Ridgeline, Sagimet, Terns, and Viking., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Non-alcoholic steatohepatitis (NASH) and type 2 diabetes are closely linked, yet the pathophysiological mechanisms underpinning this bidirectional relationship remain unresolved. Using proteomic approaches, we interrogate hepatocyte protein secretion in two models of murine NASH to understand how liver-derived factors modulate lipid metabolism and insulin sensitivity in peripheral tissues. We reveal striking hepatokine remodelling that is associated with insulin resistance and maladaptive lipid metabolism, and identify arylsulfatase A (ARSA) as a hepatokine that is upregulated in NASH and type 2 diabetes. Mechanistically, hepatic ARSA reduces sulfatide content and increases lysophosphatidylcholine (LPC) accumulation within lipid rafts and suppresses LPC secretion from the liver, thereby lowering circulating LPC and lysophosphatidic acid (LPA) levels. Reduced LPA is linked to improvements in skeletal muscle insulin sensitivity and systemic glycemic control. Hepatic silencing of Arsa or inactivation of ARSA's enzymatic activity reverses these effects. Together, this study provides a unique resource describing global changes in hepatokine secretion in NASH, and identifies ARSA as a regulator of liver to muscle communication and as a potential therapeutic target for type 2 diabetes., (© 2022. The Author(s).)

Backgrounds & Aims: Obesity often leads to non-alcoholic fatty liver disease (NAFLD), which can progress from simple steatosis (non-alcoholic fatty liver (NAFL)) to non-alcoholic steatohepatitis (NASH). The accumulation of certain lipid subtypes is linked with worsening metabolic and liver disease, however, specific changes during progression from No-NAFL to NAFL then NASH are unresolved. Herein, we characterise the liver, adipose tissue and plasma lipidome of worsening NAFLD in obesity, and evaluate the utility of plasma lipids as biomarkers of NAFLD., Methods: Venous blood, liver, visceral and subcutaneous adipose tissue samples were obtained from 181 patients undergoing bariatric surgery. NAFLD severity was assessed histologically. Lipidomic analysis was performed using liquid chromatography-tandem mass spectrometry., Results: The liver lipidome showed substantial changes with increasing steatosis, with increased triacylglycerols, diacylglycerols and sphingolipids including ceramide, dihydroceramide, hexosyl-ceramide and GM3 ganglioside species. These lipid species were also increased in plasma with increasing hepatic steatosis and showed strong correlations with liver lipids. Adipose tissue lipidomes showed no correlation with NAFLD. There were no significant changes in liver lipids with NASH compared to NAFL. The addition of plasma lipid variables to routine markers yielded significant improvements in diagnostic accuracy for NASH (AUROC 0.667 vs. 0.785, p = 0.025)., Conclusion: Overall, these data provide a detailed description of the lipidomic changes with worsening NAFLD, showing significant changes with steatosis but no additional changes with NASH. Alterations in the liver lipidome are paralleled by similar changes in plasma. Further investigation is warranted into the potential utility of plasma lipids as non-invasive biomarkers of NAFLD in obesity., Lay Summary: Non-alcoholic fatty liver disease (NAFLD) is characterised by distinct changes in the liver lipidome with steatosis. The development of non-alcoholic steatohepatitis (NASH) does not result in further changes in the lipidome. Lipids within body fat do not appear to influence the lipid profile of the liver or blood. Changes in liver lipids are paralleled by changes in blood lipids. This has potential to be developed into a non-invasive biomarker for NAFLD., Clinical Trial Number: ACTRN12615000875505., Competing Interests: Conflict of interest WB reports financial support for a bariatric surgery registry from the Commonwealth of Australia, Apollo Endosurgery, Covidien, Johnson and Johnson, Gore and Applied Medical. She has also received a speaker’s honorarium from Merck Sharpe and Dohme and a speaker’s honorarium and fees from participation in a scientific advisory board from Novo Nordisk. The Bariatric Registry and the honorariums are outside of the submitted work. GJO was supported by scholarships from the National Health and Medical Research Council (NHMRC) (APP1114811) and the Royal Australasian College of Surgeons. MJW is supported by a Senior Research Fellowship from the NHMRC (APP1077703) and has received financial support from Gilead Sciences. PJM, BLP, KH, AE, SKR, and WK have no disclosures or conflicts of interest to declare. Please refer to the accompanying ICMJE disclosure forms for further details., (Copyright © 2021 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Ectodysplasin A (EDA) was recently identified as a liver-secreted protein that is increased in the liver and plasma of obese mice and causes skeletal muscle insulin resistance. We assessed if liver and plasma EDA is associated with worsening non-alcoholic fatty liver disease (NAFLD) in obese patients and evaluated plasma EDA as a biomarker for NAFLD. Using a cross-sectional study in a public hospital, patients with a body mass index >30 kg/m 2 (n=152) underwent liver biopsy for histopathology assessment and fasting liver EDA mRNA. Fasting plasma EDA levels were also assessed. Non-alcoholic fatty liver (NAFL) was defined as >5% hepatic steatosis and nonalcoholic steatohepatitis (NASH) as NAFLD activity score ≥3. Patients were divided into three groups: No NAFLD (n=45); NAFL (n=65); and NASH (n=42). Liver EDA mRNA was increased in patients with NASH compared with No NAFLD (P=0.05), but not NAFL. Plasma EDA levels were increased in NAFL and NASH compared with No NAFLD (P=0.03). Plasma EDA was related to worsening steatosis (P=0.02) and fibrosis (P=0.04), but not inflammation or hepatocellular ballooning. ROC analysis indicates that plasma EDA is not a reliable biomarker for NAFL or NASH. Plasma EDA was not increased in patients with type 2 diabetes and did not correlate with insulin resistance. Together, we show that plasma EDA is increased in NAFL and NASH, is related to worsening steatosis and fibrosis but is not a reliable biomarker for NASH. Circulating EDA is not associated with insulin resistance in human obesity., Clinical Trial Registration: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12615000875505, identifier ACTRN12615000875505., Competing Interests: MW has received consultancy fees from Gilead Science, Inc. WB has received grants from Johnson and Johnson, Medtronic, GORE, Applied Medical, and Novo Nordisk, and personal fees from GORE, Novo Nordisk, and Merck Sharpe and Dohme for lectures and advisory boards. All were outside the submitted work. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Bayliss, Ooi, De Nardo, Shah, Montgomery, McLean, Kemp, Roberts, Brown, Burton and Watt.)

Background: Liver biopsy remains the gold standard for characterizing and evaluating treatment response in nonalcoholic fatty liver disease (NAFLD). Liver heterogeneity and sampling variability can affect the reliability of results. This study aimed to compare histological variability of intraoperative wedge and core liver biopsies from different lobes in bariatric patients, to better inform surgeons on biopsy method and guide interpretation of results., Methods: We prospectively recruited bariatric surgical patients. Intraoperative core biopsies were taken from the left and right lobe, with a wedge biopsy taken from the left. All biopsies were graded by a specialist liver pathologist, blinded to clinical details and biopsy site. Concordance of histological findings between sites was evaluated., Results: There were 91 participants (72.2% female), mean age 46.8 ± 12.0 years, body mass index 45.9 ± 9.4 kg/m 2 . There was no significant pattern for up- or down-grading disease dependent on biopsy technique. Moderate to strong agreement was seen in the presence of NAFLD and nonalcoholic steatohepatitis (NASH, κ = 0.609-0.865, p < 0.001) between biopsy sites. Individual components (steatosis, inflammation, ballooning) showed weaker agreement (κ = 0.386-0.656, p < 0.01). Fibrosis showed particularly poor agreement (κ = 0.223-0.496, p < 0.01). Detection of pathology improved with a combination of biopsy techniques, compared to a single biopsy method., Conclusion: Overall diagnosis of NAFLD or NASH shows good agreement between biopsy sites, but individual components, particularly fibrosis stage, vary significantly. Clinicians should consider biopsies from varied sites, to better assess liver disease severity. These data have important implications in fibrosis assessment of NAFLD and are relevant in the interpretation of histological efficacy of investigational pharmacotherapies., Trial Registration: ACTRN12615000875505 (Australian Clinical Trials Register).

Obesity is a strong risk factor for Barrett's esophagus (BE), the only proven precursor lesion to esophageal adenocarcinoma (EAC). Bariatric surgery is currently the only reliable treatment that achieves long-term sustained weight loss; however, it can markedly affect the development of de novo BE, and the progression or regression of existing BE. Bariatric procedures may also have implications on future surgical management of any consequent EAC. In this review, we examine the current evidence and published guidelines for BE in bariatric surgery. Current screening practices before bariatric surgery vary substantially, with conflicting recommendations from bariatric societies. If diagnosed, the presence of BE may alter the type of bariatric procedure. A selective screening approach prevents unnecessary endoscopy; however, there is poor symptom correlation with disease. Studies suggest that sleeve gastrectomy predisposes patients to gastroesophageal reflux and de novo BE. Conversely, Roux-en-Y gastric bypass is associated with decreased reflux and potential improvement or resolution of BE. There are currently no guidelines addressing the surveillance for BE following bariatric surgery. BE is an important consideration in the management of bariatric surgical patients. Evidence-based recommendations are required to guide procedure selection and postoperative surveillance., (© 2020 New York Academy of Sciences.)

Introduction: Preoperative very low energy diets (VLEDs) improve access during bariatric surgery. Compliance with traditional VLED is variable, mainly due to gastrointestinal side effects. Formulite™ is a new formulation of VLED, with higher protein, soluble fibre and probiotics., Aims: To compare traditional VLED (Optifast™) with the new VLED (Formulite™) and assess compliance, weight loss, satisfaction, side effects and surgical access., Methods: This was a randomised double-blinded study involving patients scheduled for bariatric surgery. The primary outcome was compliance, assessed by urinary ketone concentration and proportion of patients in ketosis at 2 weeks. Secondary outcomes were weight loss, satisfaction and patient reported outcomes, gastrointestinal side effects and operative conditions., Results: There were 69 participants: 35 in the Formulite™ group and 34 in the Optifast™ group. Ketosis at 2 weeks was achieved in both groups (88.5% vs 83.3%, Formulite™ vs. Optifast™, p = 0.602). Urinary ketones were higher with Formulite™ (1.5 vs 15 mmol/L, p = 0.030). Total body weight loss percentage, hunger and operative conditions were similar in both groups. Formulite™ produced less flatulence (score 3 vs 2, p = 0.010) and emotional eating (score 2 vs 1, p = 0.037); however, Optifast™ ranked higher in terms of taste (score 4 vs 3, p = 0.001) and overall satisfaction (score 5 vs 7, p = 0.011)., Conclusions: Compliance over 2 weeks was high in both VLEDs with most subjects achieving ketosis. Overall satisfaction was moderately high, although variable. Whilst Formulite™ is a viable alternative to Optifast™, better formulations of VLED that addresses key adverse effects, whilst achieving ketosis, would be of significant value.

Hepatocellular carcinoma (HCC) is one of the most fatal and fastest-growing cancers. Recently, non-alcoholic steatohepatitis (NASH) has been recognized as a major HCC catalyst. However, it is difficult to decipher the molecular mechanisms underlying the pathogenesis of NASH and understand how it progresses to HCC by studying humans. Progress in this field depends on the availability of reliable preclinical models amenable to genetic and functional analyses and exhibiting robust NASH-to-HCC progression. Although numerous mouse models of NASH have been described, many do not faithfully mimic the human disease and few reliably progress to HCC. Here, we review current literature on the molecular etiology of NASH-related HCC and critically evaluate existing mouse models and their suitability for studying this malignancy. We also compare human transcriptomic and histopathological profiles with data from MUP-uPA mice, a reliable model of NASH-driven HCC that has been useful for evaluation of HCC-targeting immunotherapies., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Non-alcoholic fatty liver disease (NAFLD), driven by the obesity epidemic, has become the most common form of liver disease. Despite this, there is controversy regarding the prevalence and severity of NAFLD in obesity. Obesity-related factors, such as increasing adiposity, metabolic disease and inflammation, may influence prevalence. We therefore prospectively measured NAFLD prevalence in obesity and studied factors associated with NAFLD., Materials and Methods: We recruited consecutive bariatric patients. Intraoperative liver biopsies were taken. The liver, adipose tissue and serum were collected to measure inflammation. Adipocyte cell size was measured. NAFLD severity was correlated to body mass index (BMI), metabolic health and adipose characteristics., Results: There were 216 participants; BMI 45.9 ± 8.9 kg/m 2 , age 44.4 ± 12.1 years, 75.5% female. Overall NAFLD prevalence was 74.1%, with 17.1% having non-alcoholic steatohepatitis (NASH) and/or steatofibrosis. Odds of NASH/steatofibrosis increased independently with BMI category (odds ratio (OR) 2.28-3.46, all p < 0.05) and metabolic disease (OR 3.79, p = 0.003). These odds markedly increased when both super obesity (BMI > 50) and metabolic disease were present (OR 9.71, p < 0.001). NASH/steatofibrosis prevalence was significantly greater with diabetes, hypertension and dyslipidemia. Although greater visceral adipocyte hypertrophy was evident in NASH/steatofibrosis, there was no significant association between adipose inflammation and NASH/steatofibrosis., Conclusion: NAFLD remains endemic in obesity; however, NASH/steatofibrosis are less common than previously reported. Worsening obesity and metabolic disease increase odds of NAFLD independently, with substantially compounded effect with both. These observations may help with risk stratification in obese populations. We were unable to delineate clear associations between adipose inflammation and NASH/steatofibrosis in this obese population., Trial Registration: Australian Clinical Trials Registry ( ACTRN12615000875505 ).

Obesity is a major driver of cancer, especially hepatocellular carcinoma (HCC). The prevailing view is that non-alcoholic steatohepatitis (NASH) and fibrosis or cirrhosis are required for HCC in obesity. Here, we report that NASH and fibrosis and HCC in obesity can be dissociated. We show that the oxidative hepatic environment in obesity inactivates the STAT-1 and STAT-3 phosphatase T cell protein tyrosine phosphatase (TCPTP) and increases STAT-1 and STAT-3 signaling. TCPTP deletion in hepatocytes promoted T cell recruitment and ensuing NASH and fibrosis as well as HCC in obese C57BL/6 mice that normally do not develop NASH and fibrosis or HCC. Attenuating the enhanced STAT-1 signaling prevented T cell recruitment and NASH and fibrosis but did not prevent HCC. By contrast, correcting STAT-3 signaling prevented HCC without affecting NASH and fibrosis. TCPTP-deletion in hepatocytes also markedly accelerated HCC in mice treated with a chemical carcinogen that promotes HCC without NASH and fibrosis. Our studies reveal how obesity-associated hepatic oxidative stress can independently contribute to the pathogenesis of NASH, fibrosis, and HCC., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: In obese individuals, nonalcoholic fatty liver disease (NAFLD) is common but often goes undiagnosed, and therefore untreated. The presence of significant fibrosis is a key determinant of NAFLD progression, and liver steatosis has substantial cardiovascular implications. We aimed to determine the diagnostic accuracy of common noninvasive diagnostic tests for steatosis and fibrosis in the obese., Methods: We recruited 182 severely and morbidly obese individuals undergoing bariatric surgery (age 44 ± 12 years, body mass index 45.1 ± 8.3 kg/m 2 ). Medical history, blood tests and liver biopsy were taken on the day of surgery. Serum steatosis and fibrosis scores were calculated. In a subgroup of patients, transient elastography with controlled attenuation parameter (TE/CAP) (n = 82) and proton magnetic resonance spectroscopy ( 1 H-MRS) (n = 49) were performed., Results: 1 H-MRS had excellent diagnostic accuracy for steatosis, with strong correlation to steatosis (r = 0.647, p < 0.001), good AUROC (0.852, p = 0.001), sensitivity (81.3%) and specificity (87.5%). However, due to low feasibility in this cohort (65.3% success), this was substantially decreased with intention-to-diagnose analysis (sensitivity 50.0%, specificity 60.9%). CAP had good feasibility (80.5%), and performed better in intention-to-diagnose analysis (AUROC 0.688, sensitivity 84.8%, specificity 47.2%). Serum steatosis scores performed poorly, with comparable accuracy to ALT. For significant fibrosis, TE had the best accuracy (AUROC 0.903, p = 0.007), which remained reasonable after intention-to-diagnose analysis (sensitivity 100%, specificity 59.0%). A combination approach using CAP with ALT for steatosis and TE with Forn index for fibrosis yielded reasonable overall accuracy., Conclusions: 1 H-MRS and TE/CAP had greatest accuracy for NAFLD-related steatosis and fibrosis. Failure rates in obesity significantly diminished diagnostic ability. Use of a combination of serum and imaging tests improved overall feasibility of assessment and diagnostic accuracy in obese individuals.

Background: Radical surgical resection is the mainstay of curative treatment for oesophagogastric malignancy. However, survival and recurrence rates remain poor. Theoretical data suggests that the inflammatory response to surgery can promote tumour recurrence. The local and systemic inflammatory response to radical oesophagogastric cancer surgery has not been fully characterized. We aimed to measure this response, particularly factors associated with tumour implantation., Methods: Consecutive patients undergoing radical junctional or gastric cancer resection over 12 months were recruited. Repeated serum and adipose tissue were collected intra-operatively. Adipose tissue was collected adjacent and remote to the tumour, and cytokine messenger RNA (mRNA) expression was measured. Post-operatively, daily serum was collected for 7 days, and analysed for inflammatory cell profile and cytokine concentration., Results: There were nine patients recruited (67.1 ± 2.1 years). mRNA expression of interleukin-6 (IL-6), CC-chemokine ligand-2 and IL-1β increased in adipose tissue intra-operatively (P < 0.05), equally both adjacent and remote from the tumour site. Serum IL-6 concentration increased from 23.3 pg/mL to 161.8 pg/mL intra-operatively (P < 0.05) before falling steadily to 35.7 pg/mL post-operatively (P < 0.05). Serum tumour necrosis factor-α was elevated throughout, and IL-1β levels were unaffected. Leukocyte and neutrophil populations increased, while T-cell and dendritic cell populations decreased intra-operatively (P < 0.05)., Conclusion: Radical surgery dramatically upregulates the expression of pro-tumourigenic cytokines in the peritoneum. There is also a marked systemic immune and inflammatory response to surgery, including downregulation of T-cell and dendritic cell populations. This offers two potential pathways that may facilitate tumour progression - local inflammation promoting peritoneal adherence and implantation, and secondary suppression of immunosurveillance due to circulating inflammatory response., (© 2017 Royal Australasian College of Surgeons.)

Introduction: Dyslipidemia affects up to 75% of morbidly obese individuals and is a key driver of cardiovascular disease. Weight loss is an established strategy to improve metabolic risk, including dyslipidemia. We aimed to determine weight loss goals for resolution of serum lipid abnormalities, by measuring improvements during progressive weight loss in obese individuals., Methods: We performed a prospective cohort study of obese individuals with the metabolic syndrome undergoing adjustable gastric banding. Lipid levels were monitored monthly for 9 months, then three monthly until 24 months., Results: There were 101 participants included, age 47.4 ± 10.9 years with body mass index 42.6 ± 5.9 kg/m 2 . At 24 months, total body weight loss (TBWL) was 18.3 ± 7.9%. This was associated with significant improvements in high-density lipoprotein (HDL) (1.18 vs 1.47, p < 0.001), triglyceride (2.0 vs 1.4, p < 0.001), and total cholesterol to HDL ratio (TC:HDL) (4.6 vs 3.6, p < 0.001). Over this time, progressive and linear improvements in HDL, triglycerides, and TC:HDL were seen with incremental weight loss (observed at 2.5% TBWL intervals). Significant improvements occurred after a threshold weight loss of 7.5-12.5% TBWL was achieved, with odds ratio (OR) 1.48-2.50 for normalization. These odds improved significantly with increasing weight loss (OR 18.2-30.4 with > 25% TBWL). Despite significant weight loss, there was no significant change in low-density lipoprotein (LDL)., Conclusion: Significant improvements in triglycerides, HDL, and TC:HDL occur after 7.5-12.5% TBWL, with ongoing benefit after greater weight loss. LDL needs to be addressed independently, as this was not observed to respond to weight loss alone., Trial Registration Number: Australian Clinical Trials Registry (ACTRN12610000049077).

Background: Outcomes of oesophago-gastric cancer are poor and highly variable between centres. It is important that complex multimodal treatments are applied optimally. Low case volumes at Australian centres mean that the analysis of crude outcomes is an inadequate assessment of overall quality of care. Detailed analysis across a range of quality domains offers the opportunity to measure performance., Methods: We compared data from the UK National Oesophago-gastric Cancer Audit 2010 with the prospective Alfred Hospital oesophago-gastric cancer database., Results: There were 314 Alfred and 17 279 UK patients identified. The volume of patients assessed by the Alfred was equal to the second highest quartile in the UK trust (4-5 new cases per month). Case ascertainment was better, capturing 84% of all oesophago-gastric cancer within the Alfred prospective audit (P < 0.001). The use of staging CT and PET scans was more common among Alfred patients (99% versus 89%, P < 0.01 and 83.8% versus 17%, P < 0.01, respectively). More patients embarked on a curative pathway (P < 0.01), with greater use of neo-adjuvant therapies. Acceptable lymph node yields were less in oesophagectomies (88.2% versus 96.2%, P < 0.01) and similar in gastrectomies (77.4% versus 74.6%, P = 0.61). Higher overall complications were observed in Alfred patients (P < 0.01), predominantly due to respiratory complications. Perioperative mortality after resection and 1-year survival was similar., Conclusions: Comparing a range of quality domains as a means of identifying areas of deficiency is feasible. This allows for contemporaneous improvements in service quality and may be more appropriate in the Australian setting than focusing on volume., (© 2016 Royal Australasian College of Surgeons.)

Background: Non-alcoholic fatty liver disease (NAFLD) and its progressive form, non-alcoholic steatohepatitis (NASH), are endemic in obesity. We aimed to evaluate the diagnostic accuracy and reproducibility of a simple intraoperative visual liver score to stratify the risk of NASH and NAFLD in obesity and determine the need for liver biopsy., Methods: This is a prospective cohort study of obese adults undergoing bariatric surgery. The surgical team used a visual liver score to evaluate liver colour, size and surface. This was compared to histology from an intraoperative liver biopsy., Results: There were 152 participants, age 44.6 ± 12 years, BMI 45 ± 8.3 kg/m 2 . Prevalence of NAFLD was 70.4%, with 12.1% NASH and 26.4% borderline NASH. Single-visual components were less accurate than total composite score. Steatosis was most accurately identified (significant steatosis: AUROC 0.746, p < 0.05; severe steatosis: AUROC 0.855, p < 0.05). NASH was identified with moderate accuracy (AUROC 0.746, p = 0.001), with sensitivity 75% for a score ≥ 2. Stratification into low (≤ 1) and high-risk (≥ 4) scores accurately identified patients who should or should not have an intraoperative biopsy. Most patients with a normal-appearing liver did not have disease (94.4%). The structured visual assessment was quick and interobserver agreement was reasonable (κ = 0.53, p < 0.05)., Conclusions: A simple, structured tool based on liver appearance can be a useful and reliable tool for NAFLD risk stratification and identification of patients who would most and least benefit from a biopsy. A normal liver appearance reliably excludes significant liver disease, avoiding the need for liver biopsy in patients otherwise at high clinical risk of NASH.

Background: Non-alcoholic fatty liver disease (NAFLD) is a significant disease burden in obesity. Liver fibrosis is an important prognostic factor in NAFLD, and detection is vital. The pathophysiological changes of obesity can alter the accuracy of non-invasive NAFLD tests. We aimed to review current evidence for common non-invasive tests for NAFLD-related fibrosis in obesity., Methods: We systematically searched for studies assessing the diagnostic accuracy of 11 biomarker panels and elastography techniques for NAFLD-related fibrosis in obesity. Meta-analyses were performed where possible., Results: Thirty-eight studies were identified assessing the selected tests in obese populations. Simple biomarker panels (e.g. NAFLD fibrosis score) were the most validated. Evidence showed better accuracy of complex biomarker panels (NAFLD fibrosis score: summary receiver operator characteristic [SROC] 0.795-0.813 vs. enhanced liver fibrosis: SROC 0.962); however, these were poorly validated in obesity. Elastography techniques were better studied and had high diagnostic accuracy (transient elastography: SROC 0.859; magnetic resonance elastography: SROC 0.965) but were limited by BMI-dependent failure. Limited evidence was found to validate the accuracy of any test in exclusively obese populations., Conclusion: In obese subjects, complex biomarker panels and elastography have been reasonable to good accuracy for NAFLD-related fibrosis; however, these methods have not been well validated. Further study in this high-risk population is needed., (© 2017 World Obesity Federation.)

Introduction: The effect of the laparoscopic adjustable gastric band (LAGB) on esophageal acid exposure and reflux is poorly understood. Optimal technique and normative values for acid exposure have not been established in this group., Methods: High-resolution manometry (HRM) and 24-h ambulatory esophageal pH monitoring were performed in three groups: asymptomatic LAGB, symptomatic LAGB, and pre-operative reflux patients. This technique utilized intraluminal pressure signatures during HRM to guide accurate pH sensor placement., Results: The LAGB groups were well matched: age 48 vs 51 years (p = 0.249), weight loss 27.3 vs 26.7 kg (p = 0.911). The symptomatic group had a larger gastric pouch (5.2 vs 3.3 cm, p = 0.012), with higher esophageal acid exposure (10.8 vs 0.9%, p < 0.001). Two acidification patterns were observed: irritant and volume acidification, associated with substantial supine acidification. Symptomatic LAGB had altered esophageal motility, with poorer lower esophageal sphincter basal tone (8.0 vs 17.7 mmHg, p = 0.022) and impaired contractility of the lower esophageal segment (90 vs 40%, p = 0.009). Compared to pre-operative reflux patients, symptomatic LAGB patients demonstrated higher total and supine esophageal acid exposure (10.8 vs 7.0%, p = 0.010; 14.9 vs 5.1%, p < 0.001), less symptoms (2 vs 6, p = 0.001) and lower symptom index (0.7 vs 0.9, p = 0.010)., Conclusions: Ambulatory pH monitoring is an effective technique if the pH sensor is positioned appropriately using HRM. The correctly positioned LAGB appears associated with low esophageal acidification. In contrast, patients with symptoms or pouch dilatation can have markedly elevated esophageal acidification, particularly when supine. This is a different pattern compared to pre-operative patients and importantly can be disproportionate to symptoms.

Background: Substantial weight loss in the setting of obesity has considerable metabolic benefits. Yet some studies have shown improvements in obesity-related metabolic comorbidities with more modest weight loss. By closely monitoring patients undergoing bariatric surgery, we aimed to determine the effects of weight loss on the metabolic syndrome and its components and determine the weight loss required for their resolution., Methods: We performed a prospective observational study of obese participants with metabolic syndrome (Adult Treatment Panel III criteria) who underwent laparoscopic adjustable gastric banding. Participants were assessed for all criteria of the metabolic syndrome monthly for the first 9 months, then 3-monthly until 24 months., Results: There were 89 participants with adequate longitudinal data. Baseline body mass index was 42.4±6.2 kg m -2 with an average age was 48.2±10.7 years. There were 56 (63%) women. Resolution of the metabolic syndrome occurred in 60 of the 89 participants (67%) at 12 months and 60 of the 75 participants (80%) at 24 months. The mean weight loss when metabolic syndrome resolved was 10.9±7.7% total body weight loss (TBWL). The median weight loss at which prevalence of disease halved was 7.0% TBWL (17.5% excess weight loss (EWL)) for hypertriglyceridaemia; 11% TBWL (26.1-28% EWL) for high-density lipoprotein cholesterol and hyperglycaemia; 20% TBWL (59.5% EWL) for hypertension and 29% TBWL (73.3% EWL) for waist circumference. The odds ratio for resolution of the metabolic syndrome with 10-12.5% TBWL was 2.09 (P=0.025), with increasing probability of resolution with more substantial weight loss., Conclusions: In obese participants with metabolic syndrome, a weight loss target of 10-12.5% TBWL (25-30% EWL) is a reasonable initial goal associated with significant odds of having metabolic benefits. If minimal improvements are seen with this initial target, additional weight loss substantially increases the probability of resolution.

Objectives: Nonalcoholic fatty liver disease (NAFLD) affects over 80% of obese patients and is fueled by the metabolic syndrome. Weight loss is strongly advocated as a central treatment for NAFLD and has been shown to induce histological improvement. We aimed to define the patterns of improvement in NAFLD with weight loss and determine target weight goals for NAFLD resolution., Methods: A prospective study of 84 morbidly obese patients with NAFLD undergoing bariatric surgery was conducted. Intraoperative liver biopsies were taken. Monthly follow-up, including blood tests and measurements, was performed. We monitored improvements in NAFLD by monthly alanine aminotransferase (ALT) and gamma glutamyltransferase (GGT) levels over 1 year., Results: There was rapid improvement in ALT, particularly in the first 6 months following surgery, with statistically significant reduction in ALT at 2 months (35 vs 27 IU/L, p < 0.001). In multivariate analysis, there were significantly increased odds of ALT normalization after a %TBWL of 10-15% (odds ratio 2.49, p = 0.005). The odds of resolution increased with increasing weight loss. Triglyceride levels (odds ratio 0.59, p = 0.021) and baseline NAFLD activity score (odds ratio 0.28, p < 0.001) were also significantly related to ALT normalization. Improvements in ALT occurred prior to metabolic improvement and well before traditional ideal weight goals were reached., Conclusion: Improvements in NAFLD occurred rapidly after bariatric surgery and were closely related to weight loss and metabolic factors. A 10-15% reduction in body weight is an appropriate target to achieve substantial improvement in ALT levels., Trial Registration Number: Australian Clinical Trials Registry (ACTRN12610000049077).

Background: Patient-reported outcomes and perceptions are critical to the overall efficacy and acceptability of a surgical procedure. Outcomes, such as patient satisfaction and perceived success of the surgery and adverse symptoms, have not been described in detail following bariatric surgery. The associations and predictors of patient satisfaction have not been defined. This study aimed to examine long-term outcomes and perceptions after laparoscopic adjustable gastric banding (LAGB)., Methods: We conducted a prospective study of outcomes, satiety and adverse upper gastrointestinal symptoms, as well as quality of life and subjective patient satisfaction in LAGB patients. Data were collected at 3 years (T1) and 8 years post-operatively (T2)., Results: One-hundred and sixty patients completed follow-up at T1 and T2. The average age was 44.0 ± 11.2 years. At T2, the total body weight loss was 17.8 ± 11.9 %. Satisfaction decreased significantly between time points (8.6 ± 1.8 vs 7.2 ± 2.9, p < 0.01), and quality of life reduced slightly across all domains. Hunger scores remained low (3.8 ± 1.8 vs 3.9 ± 1.8, p = 0.61). The dysphagia score did not change significantly (p = 0.54). There was minimal change in frequency of regurgitation, although there was significant increase in patient assessment of how bothered they were by regurgitation. Multivariate analysis identified increased awareness of regurgitation as a principal driver of reduced satisfaction., Conclusions: Weight loss, satiety and adverse symptoms demonstrated only slight changes between 3 and 8 years post-operatively. Despite this, overall satisfaction and perception of success of the procedure reduced markedly. This appeared mediated by reduced tolerance of adverse symptoms. These data inform follow-up practises aimed at optimizing outcomes.

Background: Obesity and its related comorbidities are significant risk factors for nonalcoholic fatty liver disease (NAFLD). Liver fibrosis is the major determinant of long-term outcomes in NAFLD. A non-invasive tool that accurately identifies obese patients at elevated risk of liver fibrosis would be of significant value. Fibrosis risk scores in patients with NAFLD have been proposed but have not been validated in obese populations. We aimed to validate established simple fibrosis scores in bariatric surgical patients., Methods: We conducted a prospective study of 107 consecutive high-risk obese patients undergoing primary bariatric surgery. Proposed fibrosis scores (NAFLD fibrosis score; body mass index (BMI), aspartate aminotransferase (AST)/alanine aminotransferase ratio (ALT), and diabetes (BARD); Fibrosis-4 (FIB-4); Forn; and AST to platelet ratio index) were calculated and compared hepatic fibrosis determined by histology of intraoperative liver biopsies. Accuracy was determined, and fibrosis score thresholds were optimized. These modified thresholds were then validated in an independent bariatric surgical population., Results: Liver biopsies were available in 101 patients. Sixty-eight patients had some degree of fibrosis, with 23 patients (23 %) having significant fibrosis (F2-4). The Forn score best predicted significant fibrosis (area under the receiver operator characteristic curve (AUROC) 0.724, p = 0.001). With standard thresholds, the sensitivity for the Forn score for identification of significant fibrosis (F2-4) was 0 %. Using modified thresholds of 3.5, the sensitivity and negative predictive value increased to 85.7 and 94.7 %. This threshold was applied to an independent validation cohort with good accuracy., Conclusions: Fibrosis risk scores using simple markers have moderate success at delineating obese patients with significant NAFLD-related fibrosis. Thresholds, however, need to be lowered to maximize diagnostic accuracy in this cohort.

Background: Oesophageal cancer following bariatric surgery adds significant complexity to an already challenging disease. There is limited data on the diagnosis, presentation and management in these complex cases., Methods: A retrospective cohort study on prospectively collected data over 10 years was conducted. The oesophago-gastric cancer database was searched for patients with prior bariatric surgery. Data were retrieved on bariatric and cancer management., Results: We identified nine patients with oesophageal or gastro-oesophageal junction adenocarcinoma after bariatric surgery. Mean age was 58.3 ± 6.9 years, and duration from bariatric surgery was 13.2 ± 9.4 years. Weight loss at diagnosis was 30.6 ± 23.3 kg (excess weight loss 58.1 % ± 29.6). Modes of presentation were Barrett's surveillance (n = 3), reflux symptoms (n = 4) and incidental (n = 2). Management was surgical resection (n = 4), endoscopic mucosal resection (n = 2) and palliative (n = 3). Surgical resections were challenging due to adhesions, obesity, luminal dilatation and scarring on the stomach. There were two substantial leaks following gastroplasty., Conclusions: Oesophageal cancer following bariatric surgery is a challenging problem, and surgical resection carries high risk. A high index of suspicion is required and symptoms investigated precipitously. Technical challenges of operating on obese patients and the specific effects of previous bariatric procedures need to be understood, particularly the limitations on reconstructive options.

Fourier transform infrared (FTIR) microspectroscopic imaging and small angle x-ray scattering (SAXS) were combined to investigate the supramolecular structure of collagen from 27 tissue sections from patients undergoing mastectomy, excisional biopsy, or mammoplasty. Both techniques were correlated by matching the scattering profile from the SAXS data with the integrated area of the infrared collagen region (1300-1180 cm(-1)). The FTIR spectral profiles and multivariate analysis of various tissue components showed consistent differences between all major tissue components, particularly between cancer and normal tissue cells. Analysis of the SAXS data revealed broad differences between cancer and normal tissue, but were inconclusive due to the small sample size. Parameters were extracted from each technique in relation to their characterization of collagen to reveal a good correlation between the two techniques, which diagnostically parallels with gold-standard Hematoxylin and Eosin (H&E) stained sections. The results show that the integrated area of collagen region in the FTIR spectrum for cancerous samples is greater than that for noncancerous samples indicating collagen disorder. This supports the notion that collagen is structurally disrupted in cancer tissue consistent with the interpretation of the SAXS data. Overall, both these techniques successfully distinguished cancer from normal breast tissue. Integration of these two techniques was able to better segregate cancer as well as provide a more complete understanding of the differences in collagen on all structural levels during breast cancer development.