Post-operative complications of cholecystectomy: what the radiologist needs to know.

Cholecystectomy is one of the most performed surgical procedures. The safety of this surgery notwithstanding, the sheer volume of operations results in a notable incidence of post-cholecystectomy complications. Early and accurate diagnosis of such complications is essential for timely and effective management. Imaging techniques are critical for this purpose, aiding in distinguishing between expected postsurgical changes and true complications. This review highlights current knowledge on the indications for cholecystectomy, pertinent surgical anatomy and surgical technique, and the recognition of anatomical variants that may complicate surgery. The article also outlines the roles of various imaging modalities in identifying complications, the spectrum of possible postsurgical anatomical changes, and the implications of such findings. Furthermore, we explore the array of complications that can arise post-cholecystectomy, such as biliary system injuries, gallstone-related issues, vascular complications, and the formation of postsurgical collections. Radiologists should be adept at identifying normal and abnormal postoperative findings to guide patient management effectively.

Endoscopic retrograde cholangiopancreatography-related early perforations: A study of effects of procedure duration, complexity, and endoscopist experience.

BACKGROUND: Perforations (Perf) during endoscopic retrograde cholangiopancreatography (ERCP) are rare (< 1%) but potentially fatal events (up to 20% mortality). Given its rarity, most data is through case series studies from centers or analysis of large databases. Although a meta-analysis has shown fewer adverse events as a composite (bleeding, pancreatitis, Perf) during ERCP performed at high-volume centers, there is very little real-world data on endoscopist and center procedural volumes, ERCP duration and complexity on the occurrence of Perf. AIM: To study the profile of Perf related to ERCP by center and endoscopist procedure volume, ERCP time, and complexity from a national endoscopic repository. METHODS: Patients from clinical outcomes research initiative-national endoscopic database (2000-2012) who underwent ERCP were stratified based on the endoscopist and center volume (quartiles), and total procedure duration and complexity grade of the ERCP based on procedure details. The effects of these variables on the Perf that occurred were studied. Continuous variables were compared between Perf and no perforations (NoPerf) using the Mann-Whitney U test as the data demonstrated significant skewness and kurtosis. RESULTS: A total of 14153 ERCPs were performed by 258 endoscopists, with 20 reported Perf (0.14%) among 16 endoscopists. Mean patient age in years 61.6 ± 14.8 vs 58.1 ± 18.8 (Perf vs. NoPerf, P = NS). The cannulation rate was 100% and 91.5% for Perf and NoPerf groups, respectively. 13/20 (65%) of endoscopists were high-volume performers in the 4th quartile, and 11/20 (55%) of Perf occurred in centers with the highest volumes (4th quartile). Total procedure duration in minutes was 60.1 ± 29.9 vs 40.33 ± 23.5 (Perf vs NoPerf, P < 0.001). Fluoroscopy duration in minutes was 3.3 ± 2.3 vs 3.3 ± 2.6 (Perf vs NoPerf P = NS). 50% of the procedures were complex and greater than grade 1 difficulty. 3/20 (15%) patients had prior biliary surgery. 13/20 (65%) had sphincterotomies performed with stent insertion. Peritonitis occurred in only 1/20 (0.5%). CONCLUSION: Overall adverse events as a composite during ERCP are known to occur at a lower rate with higher volume endoscopists and centers. However, Perf studied from the national database show prolonged and more complex procedures performed by high-volume endoscopists at high-volume centers contribute to Perf.

EUS-guided versus percutaneous liver biopsy: A prospective randomized clinical trial.

Background and Objectives: Prospective studies comparing EUS-guided liver biopsy (EUS-LB) to percutaneous LB (PC-LB) are scarce. We compared the efficacy and safety of EUS-LB with those of PC-LB in a prospective randomized clinical trial. Methods: Between 2020 and 2021, patients were enrolled and randomized (1:1 ratio). The primary outcome was defined as the proportion of patients with ≥11 complete portal tracts (CPTs). The sample size (n = 80) was calculated based on the assumption that 60% of those in the EUS-LB and 90% of those in the PC-LB group will have LB with ≥11 CPTs. The secondary outcomes included proportion of patients in whom a diagnosis was established, number of CPTs, pain severity (Numeric Rating Scale-Pain Intensity), duration of hospital stay, and adverse events. Results: Eighty patients were enrolled (median age, 53 years); 67.5% were female. Sixty percent of those in the EUS-LB and 75.0% of those in the PC-LB group met the primary outcome (P = 0.232). The median number of CPTs was higher in the PC-LB (17 vs 13; P = 0.031). The proportion of patients in whom a diagnosis was established was similar between the groups (92.5% [EUS-LB] vs 95.0% [PC-LB]; P = 1.0). Patients in the EUS-LB group had less pain severity (median Numeric Rating Scale-Pain Intensity, 2.0 vs 3.0; P = 0.003) and shorter hospital stay (2.0 vs 4.0 hours; P < 0.0001) compared with the PC-LB group. No patient experienced a serious adverse event. Conclusions: EUS-guided liver biopsy was safe, effective, better tolerated, and associated with a shorter hospital stay.

Mushroom Sign: Complete Esophageal Obstruction After Esophageal Variceal Band Ligation With Successful Removal of Variceal Band.

Esophageal varices due to portal hypertension are treated with endoscopic variceal band ligation (EVBL), a minimally invasive procedure with potential complications, such as pain, bleeding, and stricture formation. Rarely, complete esophageal obstruction can occur secondary to edema of the mucosa. Most cases can be managed conservatively, but intervention is necessary for severe symptoms with a risk for aspiration and airway compromise. Since EVBL is such a common procedure, it is important for clinicians to be aware of this rare but severe complication. An 80-year-old woman presented with severe dysphagia and chest discomfort after a recent EVBL. Esophagogastroduodenoscopy revealed esophageal mucosal edema and complete obstruction of the esophageal lumen. The band was removed with a loop cutter with subsequent balloon dilation to relieve the obstruction.

Gastroduodenal artery embolization for peptic ulcer hemorrhage refractory to endoscopic intervention: A single-center experience.

Objective: To determine the efficacy of gastroduodenal artery embolization (GDAE) for bleeding peptic ulcers that failed endoscopic intervention. To identify incidence and risk factors for failure of GDAE. Materials and Methods: A retrospective review of patients who underwent GDAE for hemorrhage from peptic ulcer disease refractory to endoscopic intervention were included in the study. Refractory to endoscopic intervention was defined as persistent hemorrhage following at least two separate endoscopic sessions with two different endoscopic techniques (thermal, injection, or mechanical) or one endoscopic session with the use of two different techniques. Demographics, comorbidities, endoscopic and angiographic findings, significant post-embolization pRBC transfusion, and index GDAE failure were collected. Failure of index GDAE was defined as the need for re-intervention (repeat embolization, endoscopy, or surgery) for rebleeding or mortality within 30 days after GDAE. Multivariate analyzes were performed to identify independent predictors for failure of index GDAE. Results: There were 70 patients that underwent GDAE after endoscopic intervention for bleeding peptic ulcers with a technical success rate of 100%. Failure of index GDAE rate was 23% (n = 16). Multivariate analysis identified ≥2 comorbidities (odds ratio [OR]: 14.2 [1.68-19.2], P = 0.023), days between endoscopy and GDAE (OR: 1.43 [1.11-2.27], P = 0.028), and extravasation during angiography (OR: 6.71 [1.16-47.4], P = 0.039) as independent predictors of index GDAE failure. Endoscopic Forrest classification was not a significant predictor for the failure of index GDAE (P > 0.1). Conclusion: The study demonstrates safety and efficacy of GDAE for hemorrhage from PUD that is refractory to endoscopic intervention. Days between endoscopy and GDAE, high comorbidity burden, and extravasation during angiography are associated with increased risk for failure of index GDAE.

The Utility and Diagnostic Accuracy of Transient Elastography in Adults with Morbid Obesity: A Prospective Study.

Patients with morbid obesity are at high risk for nonalcoholic fatty liver disease (NAFLD) complicated by liver fibrosis. The clinical utility of transient elastography (TE) by Fibroscan in patients with morbid obesity (body mass index (BMI) ≥ 40 kg/m2) is not well-defined. We examined the diagnostic accuracy of Fibroscan in predicting significant liver fibrosis (fibrosis stage ≥2) in morbidly obese patients (BMI ≥ 40 kg/m2). Patients scheduled for bariatric surgery were prospectively enrolled. Intraoperative liver biopsy, liver-stiffness measurement (LSM) by Fibroscan (XL probe), and biochemical evaluation were all performed on the same day. The endpoint was significant liver fibrosis defined as fibrosis stage ≥2 based on the Nonalcoholic Steatohepatitis Clinical Research Network. The optimal LSM cutoff value for detecting significant fibrosis was determined by using the Youden Index method. Routine clinical, laboratory, and elastography data were analyzed by stepwise logistic regression analysis to identify predictors of significant liver fibrosis and build a predictive model. An optimal cutoff point of the new model's regression formula for predicting significant fibrosis was determined by using the Youden index method. One hundred sixty-seven patients (mean age, 46.4 years) were included, of whom 83.2% were female. Histological assessment revealed the prevalence of steatohepatitis and significant fibrosis of 40.7% and 11.4%, respectively. The median LSM was found to be significantly higher in the significant fibrosis group compared to those in the no or non-significant fibrosis group (18.2 vs. 7.7 kPa, respectively; p = 0.0004). The optimal LSM cutoff for predicting significant fibrosis was 12.8 kPa, with an accuracy of 71.3%, sensitivity of 73.7%, specificity of 70.9%, positive predictive value of 24.6%, negative predictive value of 95.5%, and ROC area of 0.723 (95% CI: 0.62-0.83). Logistic regression analysis identified three independent predictors of significant fibrosis: LSM, hemoglobin A1c, and alkaline phosphatase. A risk score was developed by using these three variables. At an optimal cutoff value of the regression formula, the risk score had an accuracy of 79.6% for predicting significant fibrosis, sensitivity of 89.5%, specificity of 78.4%, positive predictive value of 34.7%, negative predictive value of 98.3%, and ROC area of 0.855 (95% CI: 0.76-0.95). Fibroscan utility in predicting significant liver fibrosis in morbidly obese subjects is limited with accuracy of 71.3%. A model incorporating hemoglobin A1c and alkaline phosphatase with LSM improves accuracy in detecting significant fibrosis in this patient population.

Compromised hepatic mitochondrial fatty acid oxidation and reduced markers of mitochondrial turnover in human NAFLD.

BACKGROUND AND AIMS: NAFLD and its more-advanced form, steatohepatitis (NASH), is associated with obesity and is an independent risk factor for cardiovascular, liver-related, and all-cause mortality. Available human data examining hepatic mitochondrial fatty acid oxidation (FAO) and hepatic mitochondrial turnover in NAFLD and NASH are scant. APPROACH AND RESULTS: To investigate this relationship, liver biopsies were obtained from patients with obesity undergoing bariatric surgery and data clustered into four groups based on hepatic histopathological classification: Control (CTRL; no disease); NAFL (steatosis only); Borderline-NASH (steatosis with lobular inflammation or hepatocellular ballooning); and Definite-NASH (D-NASH; steatosis, lobular inflammation, and hepatocellular ballooning). Hepatic mitochondrial complete FAO to CO2 and the rate-limiting enzyme in ß-oxidation (ß-hydroxyacyl-CoA dehydrogenase activity) were reduced by ~40%-50% with D-NASH compared with CTRL. This corresponded with increased hepatic mitochondrial reactive oxygen species production, as well as dramatic reductions in markers of mitochondrial biogenesis, autophagy, mitophagy, fission, and fusion in NAFL and NASH. CONCLUSIONS: These findings suggest that compromised hepatic FAO and mitochondrial turnover are intimately linked to increasing NAFLD severity in patients with obesity.

Comparison of postpolypectomy bleeding events between cold snare polypectomy and hot snare polypectomy for small colorectal lesions: a large-scale propensity score-matched analysis.

BACKGROUND AND AIMS: Cold snare polypectomy (CSP), a safe procedure for removing colon polyps, has a low prevalence of postpolypectomy bleeding (PPB). Previous studies have failed to demonstrate differences in PPB rates between CSP and hot snare polypectomy (HSP), possibly because of their small sample sizes. This study analyzed PPB rates after CSP and HSP. METHODS: This was a retrospective analysis of colorectal lesions (diameter <10 mm) treated using endoscopic resection at our institution between January 2015 and December 2019. Resections were performed using CSP or HSP, depending on the endoscopist's preference. Endoscopic and histologic findings were recorded in the endoscopic database at our institution. Propensity score (PS) matching was performed to match patient age, lesion size, macroscopic features, location of the lesions, clipping after resection, and antithrombotic agent use. The CSP and HSP groups were compared to determine the adverse event (PPB) rates. RESULTS: The CSP and HSP groups included 12,928 and 2408 lesions (total of 5371 patients), respectively. Univariate analysis revealed that the overall prevalence of PPB after HSP was higher than that after CSP (odds ratio [OR], 5.39; 95% confidence interval [CI], 2.50-11.60). After PS matching (2135 lesions per group), the prevalence of PPB after HSP remained higher than that after CSP (OR, 6.0; 95% CI, 1.34-26.8). CONCLUSIONS: For colorectal lesions <10 mm in diameter, the risk of PPB after CSP is significantly lower than that after HSP, after PS matching. CSP for lesions <10 mm could be safely performed compared with HSP.

A Model Incorporating Serum Alkaline Phosphatase for Prediction of Liver Fibrosis in Adults with Obesity and Nonalcoholic Fatty Liver Disease.

We assessed the relationship between serum alkaline phosphatase (ALP) and liver fibrosis by histology, in addition to other noninvasive parameters, in obese patients undergoing metabolic surgery. Patients scheduled for elective bariatric surgery were prospectively recruited from a bariatric clinic. An intraoperative liver biopsy was performed, and liver histology was evaluated by a pathologist blinded to the patients' data. The endpoint was significant fibrosis defined as fibrosis stage ≥ 2. Independent predictors of fibrosis were identified by logistic regression. Two hundred ten patients were recruited. Liver histology revealed steatosis in 87.1%, steatohepatitis in 21.9%, and significant fibrosis in 10%. Independent predictors of significant fibrosis were ALP (Odds Ratio (OR) 1.03; 95% Confidence interval (CI), 1.01-1.05), alanine aminotransferase (OR 1.02; 95% CI, 1.01-1.03), HbA1c (OR 1.58; 95% CI, 1.20-2.09), and body mass index (OR 1.06; 95% CI, 1.00-1.13). A tree-based model was developed to predict significant fibrosis, with a receiver operating characteristic (ROC) area of 0.845, sensitivity of 0.857, specificity of 0.836, and accuracy of 0.931. The applicability of serum ALP as an independent biomarker of liver fibrosis should be considered in obesity surgery patients, and in the broader context of obese patients with nonalcoholic fatty liver disease.

Newly Reported Studies on the Increase in Gastrointestinal Symptom Prevalence withCOVID-19 Infection: A Comprehensive Systematic Review and Meta-Analysis.

BACKGROUND AND AIM: Although constitutional and respiratory symptoms such as cough and fever are the most common symptoms in patients infected with COVID-19, gastrointestinal (GI) tract involvement has been observed by endoscopic biopsies. Multiple GI symptoms, including diarrhea, nausea or vomiting and abdominal pain, have also been reported. This review aims to present the currently available data regarding the GI symptoms of COVID-19 patients, and to compare the frequency of GI symptoms in early stage (Eastern) mostly Chinese data to the current stage (Western) non-Chinese data. METHODS: We performed a systematic literature search to identify both published studies by using PubMed, Google Scholar, and CNKI (Chinese medical search engine), and yet unpublished studies through medRxiv and bioRxiv. We also reviewed the cross references of the detected articles. We conducted a Medical Subject Headings (MeSH) search up until 20 September 2020. We pooled the prevalence of symptoms of diarrhea, anorexia, nausea, vomiting, and abdominal pain by using the Freeman-Tukey's transforming random effect model. RESULTS: A total of 118 studies were included in the systematic review and 44 of them were included in the meta-analysis. There was a significant heterogeneity between the studies; therefore, the random effects model was used. The pooled prevalence estimate of any GI symptoms reported was found to be 0.21 (95%CI, 0.16-0.27). Anorexia was the most commonly reported GI symptom at 18% (95%CI, 0.10-0.27) followed by diarrhea at 15% (95%CI, 0.12-0.19). Diarrhea, abdominal pain, nausea/vomiting, and respiratory symptoms were more common in non-Chinese studies. The prevalence of abdominal pain was lower in the "inpatient-only" studies when compared with studies that included outpatients only and those including both inpatients and outpatients. CONCLUSIONS: In this comprehensive systematic review and meta-analysis study, we observed higher rates of diarrhea, nausea/vomiting, and abdominal pain in COVID-19 infected patients among non-Chinese studies compared to Chinese studies. We also observed a higher prevalence of GI symptoms in Chinese studies than was reported previously. Non-respiratory symptoms, including GI tract symptoms, should be more thoroughly and carefully evaluated and reported in future studies.

The efficacy and safety of endoscopic ultrasound-guided liver biopsy versus percutaneous liver biopsy in patients with chronic liver disease: a retrospective single-center study.

BACKGROUND AND AIMS: There is limited literature on endoscopic ultrasound-guided liver biopsy (EUS-LB), a new method of obtaining liver biopsy (LB). METHODS: We conducted a retrospective study of the efficacy and safety of EUS-LB compared to percutaneous liver biopsy (PC-LB) in patients with chronic liver disease at our center between January 2018 and August 2019. RESULTS: Thirty patients underwent EUS-LB and 60 patients underwent PC-LB were identified (median follow-up post-LB was 8 days; interquartile range (IQR), 3-5 days). The median number of portal tracts was significantly higher in the PC-LB group (13 vs. 5; P < 0.0001). A histologic diagnosis was established in 93% of the EUS-LB group, compared to 100% in the PC-LB group (P = 0.841). Patients in EUS-LB group had significantly shorter hospital stay (median time of hospital stay was 3 vs. 4.2 h in the EUS-LB vs. PC-LB group, respectively; P = 0.004) and reported less pain compared to PC-LB group (median pain score was 0 vs. 3.5; P = 0.0009). EUS-LB were performed using a 19-gauge (n = 27) or 22-gauge (n = 3); there was a tendency towards higher number of portal tracts in the 22- vs. the 19-gauge needle group (6 vs. 5; P = 0.501). No patient in either group had significant adverse events such as bleeding or death. CONCLUSION: EUS-LB is safe and is associated with less pain, shorter hospital stay, and high diagnostic yield (93%) compared to PC-LB. Randomized trials are needed to standardize the utility of EUS-LB.

Defects in long-chain 3-hydroxy acyl-CoA dehydrogenase lead to hepatocellular carcinoma: A novel etiology of hepatocellular carcinoma.

The incidence of both nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) have been increasing at an alarming rate. Little is known about NAFLD without cirrhosis as a risk for HCC. Here we report, for the first time, generation of a mouse model with a defect in long-chain 3-hydoxy acyl-CoA dehydrogenase (LCHAD). The LCHAD exon 15 deletion was embryonic lethal to the homozygous mice whereas heterozygous mice (HT) develop significant hepatic steatosis starting at young age (3 months old) and HCC at older age (>13 months old) without any evidence of fibrosis or cirrhosis. None of the wild-type (WT) mice developed steatosis and HCC (n = 39), whereas HT-LCHAD mice (n = 41) showed steatosis and ~20% (8/41) developed liver masses with histological features of HCC. Proteomic analysis of liver tissues from WT-mice and HT-mice with no signs of HCC was conducted. Proteins with significant changes in abundance were identified by mass spectrometry. Abundance of 24 proteins was significantly different (p < 0.01) between WT and HT-LCHAD mice. The proteins found to vary in abundance are associated with different cellular response processes ranging from intermediary metabolism of carbohydrate, protein and lipid to oxidative stress, signal transduction and the process of tumorigenesis. Protein expression pattern of the HT-LCHAD mouse liver indicates predisposition to HCC and suggests that impaired hepatic mitochondrial fatty acid oxidation plays an important role in the development and progression of HCC. To assess the implication of these studies in human disease, we demonstrated significant downregulation of HADHA transcripts in HCC patients.

A rare case of plexiform fibromyxoma in stomach: FNA diagnosis with histological correlation and differential diagnoses.

Plexiform angiomyxoma (PF) is a rare benign mesenchymal neoplasm that arises in the antrum and pyloric region of the stomach. To the best of our knowledge, there are only two prior endoscopic ultrasound guided fine needle aspiration cytology examples have been reported. We report a case of PF which was diagnosed via EUS FNA and later confirmed on resection specimen. Differential diagnoses of this tumor are discussed. Although diagnosis of plexiform fibromyxoma on FNA specimen is difficult, a good FNA specimen with subsequent careful morphological evaluation and immunohistochemical staining work-up makes this task possible.

Fatty Acid Synthase Inhibitor TVB-2640 Reduces Hepatic de Novo Lipogenesis in Males With Metabolic Abnormalities.

BACKGROUND AND AIMS: Elevated hepatic de novo lipogenesis (DNL) is a key distinguishing characteristic of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis. In rodent models of NAFLD, treatment with a surrogate of TVB-2640, a pharmacological fatty acid synthase inhibitor, has been shown to reduce hepatic fat and other biomarkers of DNL. The purpose of this phase I clinical study was to test the effect of the TVB-2640 in obese men with certain metabolic abnormalities that put them at risk for NAFLD. APPROACH AND RESULTS: Twelve subjects (mean ± SEM, 42 ± 2 years, body mass index 37.4 ± 1.2 kg/m2 , glucose 103 ± 2 mg/dL, triacylglycerols 196 ± 27 mg/dL, and elevated liver enzymes) underwent 10 days of treatment with TVB-2640 at doses ranging from 50-150 mg/day. Food intake was controlled throughout the study. Hepatic DNL was measured before and after an oral fructose/glucose bolus using isotopic labeling with 1-13 C1 -acetate intravenous infusion, followed by measurement of labeled very low-density lipoprotein palmitate via gas chromatography mass spectometry. Substrate oxidation was measured by indirect calorimetry. Across the range of doses, fasting DNL was reduced by up to 90% (P = 0.003). Increasing plasma concentrations of TVB-2640 were associated with progressive reductions in the percent of fructose-stimulated peak fractional DNL (R2  = -0.749, P = 0.0003) and absolute DNL area under the curve 6 hours following fructose/glucose bolus (R2  = -0.554, P = 0.005). For all subjects combined, alanine aminotransferase was reduced by 15.8 ± 8.4% (P = 0.05). Substrate oxidation was unchanged, and safety monitoring revealed that the drug was well tolerated, without an increase in plasma triglycerides. Alopecia occurred in 2 subjects (reversed after stopping the drug), but otherwise no changes were observed in fasting glucose, insulin, ketones, and renal function. CONCLUSION: These data support the therapeutic potential of a fatty acid synthase inhibitor, TVB-2640 in particular, in patients with NAFLD and nonalcoholic steatohepatitis.

Removal of Esophageal Variceal Bands to Salvage Complete Esophageal Obstruction.

Esophageal varices develop in almost half of the patients with cirrhosis, and variceal hemorrhage constitutes an ominous sign with an increased risk of mortality. Variceal banding is considered an effective and mostly safe measure for primary and secondary prophylaxis. Although adverse events related to banding including dysphagia, stricture formation, bleeding, and ligation-induced ulcers have been described, complete esophageal obstruction is rare, with only 10 reported cases in the literature. Among those cases, 6 were managed conservatively; 1 patient had esophageal intraluminal dissection from an attempt to remove the bands using biopsy forceps but ultimately recovered with conservative management. Three patients developed strictures following removal of the bands, requiring repeated sessions of dilation therapy. We report on a patient who developed absolute dysphagia and complete esophageal obstruction after variceal banding. We successfully used the endoloop cutter hook to release the bands intact and restore luminal integrity.

Are we getting closer to understanding intratumor heterogeneity in hepatocellular carcinoma?

Hepatocellular carcinoma (HCC) is a highly heterogenous disease and intratumor heterogeneity is a well-known fact within each individual tumor, and may involve morphological, immunohistochemical, and molecular heterogeneities. Understanding of intratumor heterogeneity of HCC should provide critical knowledge about prognosis of the disease and response to therapy. In a recent article by Friemel and colleagues, the investigators utilized a comprehensive approach in linking immunohistochemical markers and molecular changes to morphological intratumor heterogeneity in HCC. The study found that intratumor heterogeneity was detectable in 87% of HCC cases. Combined heterogeneities with respect to morphologic, immunohistochemical, and mutational status of the two most important driver mutations CTNNB1 and TP53 were seen in 22% of HCC cases. The study demonstrates the challenges facing therapeutic strategies targeting single molecules and may explain the limited success so far in developing molecular targeted therapy for HCC.

Pathogenesis and Prevention of Hepatic Steatosis.

Hepatic steatosis is defined as intrahepatic fat of at least 5% of liver weight. Simple accumulation of triacylglycerols in the liver could be hepatoprotective; however, prolonged hepatic lipid storage may lead to liver metabolic dysfunction, inflammation, and advanced forms of nonalcoholic fatty liver disease. Nonalcoholic hepatic steatosis is associated with obesity, type 2 diabetes, and dyslipidemia. Several mechanisms are involved in the accumulation of intrahepatic fat, including increased flux of fatty acids to the liver, increased de novo lipogenesis, and/or reduced clearance through ß-oxidation or very-low-density lipoprotein secretion. This article summarizes the mechanisms involved in the accumulation of triacylglycerols in the liver, the clinical implications, and the prevention of hepatic steatosis, with a focus on the role of mitochondrial function and lifestyle modifications.

Usefulness of endoscopic ultrasound-guided fine needle aspiration in the diagnosis of hepatic, gallbladder and biliary tract Lesions.

Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) of the liver is a safe procedure in the diagnosis and staging of hepatobiliary malignancies with a minimal major complication rate. EUS-FNA is useful for liver lesions poorly accessible to other imaging modalities of the liver. EUS-guided FNA of biliary neoplasia and malignant biliary stricture is superior to the conventional endoscopic brushing and biopsy.