Gastric intestinal metaplasia: when to treat? How to treat?

PURPOSE OF REVIEW: Gastric intestinal metaplasia (GIM) is an attractive target for surveillance and treatment as it can progress to gastric adenocarcinoma (GAC). Yet, GIM remains a challenging area for clinicians as most patients do not progress to cancer, and there are conflicting data regarding the benefits of surveillance and therapy. This review aims to summarize recently published GIM surveillance guidelines, to discuss, which patients with GIM may benefit from treatment, and to review pivotal and recent literature on GIM therapy. RECENT FINDINGS: Guidelines published by American, British, and European gastroenterology societies do not recommend universal surveillance, but do suggest endoscopic surveillance in patients with risk factors for progression to GAC. Although light examination for at least 7 min and mapping biopsies may increase yield for dysplasia and GAC. In randomized trials, Helicobacter pylori eradication reduced risk of dysplasia and cancer. In GIM with visible dysplasia and early-stage GAC, endoscopic resection improves quality of life without reducing survival compared with surgery. Endoscopic ablation therapies have shown promise for invisible or extensive dysplasia. SUMMARY: Endoscopic resection is appropriate for visible dysplasia and early-stage GAC without high-risk features that persists despite H. pylori eradication therapy. Prospective studies are needed to assess the utility of endoscopic ablation in GIM.

Surgery Reduces Risk of Complications Even in High-Risk Veterans After Endoscopic Therapy for Biliary Stone Disease.

BACKGROUND: In otherwise healthy patients, randomized trials have shown reduced mortality with cholecystectomy (CCY) when compared to non-operative management after endoscopic retrograde cholangiopancreatography (ERCP) for biliary stone disease. These findings may not apply to veterans with multiple comorbidities, who have an increased risk of postoperative complications. AIMS: Our study assessed the benefit of CCY among veterans with multiple comorbidities. METHODS: Medical records of patients undergoing ERCP for biliary stone-related diseases from July 2008 to December 2016 were reviewed. Among patients who did not undergo CCY, risk of postoperative complications or death with CCY was estimated using the American College of Surgeons National Surgery Quality Improvement Program risk calculator. Charlson comorbidity index (CCI) and American Society of Anesthesiologists classification system (ASA) were used to assess patient's functional status. The primary outcome was incidence of recurrent biliary events or death with non-operative management, compared to estimated risk of serious postoperative complications or death with CCY. RESULTS: A total of 152 patients met inclusion criteria, 81 of whom did not undergo CCY. Patients managed non-operatively were older and less medically fit than patients who underwent CCY. Biliary complications recurred in 23 patients managed non-operatively, including 3 deaths due to cholangitis. Among patients with CCI ≥ 3 and ASA ≥ 3 who were managed non-operatively (n = 43), the risk of serious biliary events was significantly higher than estimated risk of serious postoperative complications with laparoscopic CCY (26 vs 5%, p < 0.001). CONCLUSION: Our study suggests that non-operative management is associated with a higher risk of complications than laparoscopic CCY, even among veterans with significant comorbidities.

Diagnostic Accuracy of Laboratory Tests and Diagnostic Imaging in Detecting Biliary Strictures After Liver Transplantation.

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is often required to diagnose post-liver transplant (LT) biliary strictures. We evaluated the diagnostic accuracy of noninvasive laboratory and imaging tests in detecting post-LT biliary strictures. METHODS: Adult LT recipients who underwent ERCP between 2008 and 2015 were evaluated. Biliary strictures were diagnosed after blinded review of cholangiograms by three interventional endoscopists. The accuracy of liver enzymes, ultrasound, and MRI was determined using cholangiography as the reference standard. To evaluate the accuracy of change in liver enzymes, the difference between baseline and liver enzymes prior to ERCP (Δlab) was utilized. RESULTS: Biliary strictures were present on cholangiogram in 48 (58%) of 82 LT recipients meeting inclusion criteria. Baseline liver enzyme values did not differ significantly between patients with and without strictures. The optimal cutoffs for ΔALT, ΔAST, Δbilirubin, and Δalkaline phosphatase (AP) were determined to be 174 IU/L, 75 IU/L, 3.1 mg/dL, and 225 IU/L, respectively. ΔALT had a sensitivity of 100%, specificity 43%, and negative predictive value 100%. ΔAP had the highest specificity (53%) but modest sensitivity (69%) with a positive predictive value of 67%. Ultrasound had sensitivity of 29% and specificity of 69%, while MRI had sensitivity of 78% and specificity of 56%. DISCUSSION: The diagnostic accuracy of liver enzymes and imaging modalities is modest in detecting post-LT biliary strictures and cannot be used solely to identify patients needing further workup.

Candida Esophagitis Presenting as an Esophageal Pseudotumor.

The typical appearance of Candida esophagitis is white plaque-like membranes within the esophagus. We describe a unique case of Candida esophagitis that presented as a bulky, malignant-appearing, positron emission tomography-computed tomography-avid mass on endoscopy. Esophageal candidiasis persisted despite a standard course of antifungal medications (fluconazole 400 mg daily for 14 days), and eradication was successful only after fluconazole 800 mg daily was administered. Malignancy was excluded based on 2 separate sessions of endoscopy with multiple biopsies and finally with endoscopic full-thickness resection assisted by preresection closure with an over-the-scope clip.

Deep learning systems detect dysplasia with human-like accuracy using histopathology and probe-based confocal laser endomicroscopy.

Probe-based confocal laser endomicroscopy (pCLE) allows for real-time diagnosis of dysplasia and cancer in Barrett's esophagus (BE) but is limited by low sensitivity. Even the gold standard of histopathology is hindered by poor agreement between pathologists. We deployed deep-learning-based image and video analysis in order to improve diagnostic accuracy of pCLE videos and biopsy images. Blinded experts categorized biopsies and pCLE videos as squamous, non-dysplastic BE, or dysplasia/cancer, and deep learning models were trained to classify the data into these three categories. Biopsy classification was conducted using two distinct approaches-a patch-level model and a whole-slide-image-level model. Gradient-weighted class activation maps (Grad-CAMs) were extracted from pCLE and biopsy models in order to determine tissue structures deemed relevant by the models. 1970 pCLE videos, 897,931 biopsy patches, and 387 whole-slide images were used to train, test, and validate the models. In pCLE analysis, models achieved a high sensitivity for dysplasia (71%) and an overall accuracy of 90% for all classes. For biopsies at the patch level, the model achieved a sensitivity of 72% for dysplasia and an overall accuracy of 90%. The whole-slide-image-level model achieved a sensitivity of 90% for dysplasia and 94% overall accuracy. Grad-CAMs for all models showed activation in medically relevant tissue regions. Our deep learning models achieved high diagnostic accuracy for both pCLE-based and histopathologic diagnosis of esophageal dysplasia and its precursors, similar to human accuracy in prior studies. These machine learning approaches may improve accuracy and efficiency of current screening protocols.

Deep Learning for Whole-Slide Tissue Histopathology Classification: A Comparative Study in the Identification of Dysplastic and Non-Dysplastic Barrett's Esophagus.

The gold standard of histopathology for the diagnosis of Barrett's esophagus (BE) is hindered by inter-observer variability among gastrointestinal pathologists. Deep learning-based approaches have shown promising results in the analysis of whole-slide tissue histopathology images (WSIs). We performed a comparative study to elucidate the characteristics and behaviors of different deep learning-based feature representation approaches for the WSI-based diagnosis of diseased esophageal architectures, namely, dysplastic and non-dysplastic BE. The results showed that if appropriate settings are chosen, the unsupervised feature representation approach is capable of extracting more relevant image features from WSIs to classify and locate the precursors of esophageal cancer compared to weakly supervised and fully supervised approaches.

Significant infections in liver transplant recipients undergoing endoscopic retrograde cholangiography are few and unaffected by prophylactic antibiotics.

INTRODUCTION: Current practice guidelines recommend prophylactic antibiotics prior to endoscopic retrograde cholangiopancreatography (ERCP) in liver transplant recipients (LTR). This study evaluated the risk of clinically significant infections after ERCP in LTR who received antibiotic prophylaxis compared to those who did not. METHODS: This retrospective case-cohort study evaluated all LTR who underwent elective, outpatient ERCP from 2008 to 2015. Hospitalized patients, pediatric allograft recipients and patients with cholangitis or incomplete biliary drainage were excluded. The primary outcome was unanticipated hospitalization from procedure-related clinically significant infection occurring within 3 days of ERCP. RESULTS: Sixty-nine patients (48 males; mean age 60.5 ±â€¯7.4 years) underwent 191 ERCPs after liver transplantation. Prophylactic antibiotics were administered during 82 ERCPs and not administered for 109 ERCPs. Unscheduled admissions for fever within 3 days occurred in 4 patients. Only 2 patients had documented bacteremia, of which only 1 patient received prophylactic antibiotics and also met primary outcome. Interventions during ERCP, patient demographics, and time from transplantation were not associated with increased risk of hospitalization from infections or bacteremia. CONCLUSIONS: The risk of infectious complications after ERCP in LTR is low and not affected by administration of prophylactic antibiotics. A tailored approach to antibiotic prophylaxis may be more appropriate than universal prophylaxis in selected LTR at low risk of infections.

The risk of hepatocellular carcinoma in cirrhotic patients with small liver nodules on MRI.

BACKGROUND AND AIM: The presence of hepatocellular carcinoma (HCC) has important implications for patients with cirrhosis. Studies have not compared the risk of cancer in cirrhotic patients with small liver nodules to cirrhotic patients without nodules. Our aim was to determine the risk of HCC in cirrhotic patients with small liver nodules on MRI compared to those without nodules. METHODS: We conducted a prospective study to determine the rate of HCC in cirrhotic patients with and without liver nodules. Cases were patients with liver nodule(s) less than 2 cm on MRI and controls were cirrhotic patients without nodules. Kaplan-Meier estimates and multivariate analysis were performed to estimate the risk of HCC in the two groups. RESULTS: A total of 310 liver transplant candidates with a mean follow-up of 663 days were included in the study and 133 underwent liver transplant during follow-up. The 1-yr incidence of HCC in the liver nodule group and control group was 11% and 0.5%, respectively, p < 0.001. The adjusted risk for HCC in the liver nodule group was 25 times higher compared to the control group, HR = 25.1 [95% CI 8.0, 78.9]. In 133 candidates who underwent transplant with and without liver nodules the rate of HCC was 11 (50%) and 4 (3.6%), respectively, p < 0.001. CONCLUSION: The incidence of HCC in patients with small liver nodules is significantly higher compared to patients with cirrhosis without liver nodules. The presence of small liver nodules warrants increased imaging surveillance for HCC.

Accuracy of magnetic resonance imaging for preoperative detection of portal vein thrombosis in liver transplant candidates.

The detection of main portal vein thrombosis (PVT) on preoperative imaging of liver transplant candidates has important technical implications for the transplantation procedure. Data are scarce regarding the accuracy of magnetic resonance imaging (MRI) at detecting PVT. The aim of our study was to compare preoperative findings of the portal vein on MRI to operative findings at liver transplantation. Abdominal MRI and clinical records of 172 consecutive patients who received liver transplants between January 1999 and September 2004 were reviewed. Two radiologists independently evaluated the last abdominal magnetic resonance examinations obtained before liver transplantation, blinded to the original reading, operative findings, and clinical data. Findings on MRI were compared with intraoperative findings at transplantation. Main PVT was detected in 12 patients, in whom 8 were found to have thrombus at surgery, with 6 requiring a jump graft or thrombectomy. Sensitivity and specificity of MRI for detecting main PVT were 100% and 98%, respectively. The cause of discordance between findings on MRI and at transplantation in 2 cases was a diminutive caliber of the main portal vein that was interpreted as recanalized chronic thrombosis on MRI. In conclusion, in our study group MRI detected PVT in all liver transplant recipients requiring jump grafts at transplantation. The major reason for a false-positive MRI was a diminutive but patent portal vein.