Detection of Barrett's neoplasia with a near-infrared fluorescent heterodimeric peptide.

BACKGROUND: Esophageal adenocarcinoma (EAC) is a molecularly heterogeneous disease with poor prognosis that is rising rapidly in incidence. We aimed to demonstrate specific binding by a peptide heterodimer to Barrett's neoplasia in human subjects. METHODS: Peptide monomers specific for EGFR and ErbB2 were arranged in a heterodimer configuration and labeled with IRDye800. This near-infrared (NIR) contrast agent was topically administered to patients with Barrett's esophagus (BE) undergoing either endoscopic therapy or surveillance. Fluorescence images were collected using a flexible fiber accessory passed through the instrument channel of an upper gastrointestinal endoscope. Fluorescence images were collected from 31 BE patients. A deep learning model was used to segment the target (T) and background (B) regions. RESULTS: The mean target-to-background (T/B) ratio was significantly greater for high grade dysplasia (HGD) and EAC versus BE, low grade dysplasia (LGD), and squamous epithelium. At a T/B ratio of 1.5, sensitivity and specificity of 94.1 % and 92.6 %, respectively, were achieved for the detection of Barrett's neoplasia with an area under the curve of 0.95. No adverse events attributed to the heterodimer were found. EGFR and ErbB2 expression were validated in the resected specimens. CONCLUSIONS: This "first-in-human" clinical study demonstrates the feasibility of detection of early Barrett's neoplasia using a NIR-labeled peptide heterodimer.

Long-Term Quality of Life Following Endoscopic Therapy Compared to Esophagectomy for Neoplastic Barrett's Esophagus.

INTRODUCTION: Endoscopic therapy (ET) and esophagectomy result in similar survival for Barrett's esophagus (BE) with high-grade dysplasia (HGD) or T1a esophageal adenocarcinoma (EAC), but the long-term quality of life (QOL) has not been compared. AIMS: We aimed to compare long-term QOL between patients who had undergone ET versus esophagectomy. METHODS: Patients were included if they underwent ET or esophagectomy at the University of Michigan since 2000 for the treatment of HGD or T1a EAC. Two validated survey QOL questionnaires were mailed to the patients. We compared QOL between and within groups (ET = 91, esophagectomy = 62), adjusting for covariates. RESULTS: The median time since initial intervention was 6.8 years. Compared to esophagectomy, ET patients tended to be older, had a lower prevalence of EAC, and had a shorter duration since therapy. ET patients had worse adjusted physical and role functioning than esophagectomy patients. However, the adjusted odds ratio (OR) of having symptoms was significantly less with ET for diarrhea (0.287; 95% confidence interval [CI] = 0.114, 0.724), trouble eating (0.207; 0.0766, 0.562), choking (0.325; 0.119, 0.888), coughing (0.291; 0.114, 0.746), and speech difficulty (0.306; 0.0959, 0.978). Amongst the ET patients, we found that the number of therapy sessions and need for dilation were associated with worse outcomes. DISCUSSION: Multiple measures of symptom status were better with ET compared to esophagectomy following treatment of BE with HGD or T1a EAC. We observed worse long-term physical and role functioning in ET patients which could reflect unmeasured baseline functional status rather than a causal effect of ET.

Preoperative predictors of choledocholithiasis in patients presenting with acute calculous cholecystitis.

BACKGROUND AND AIMS: Markedly increased liver chemistries in patients presenting with acute calculous cholecystitis (AC) often prompt an evaluation for concomitant choledocholithiasis (CDL). However, current guidelines directing the workup for CDL fail to address this unique population. The aims of this study are to define the range of presenting laboratory values and imaging findings in AC, develop a model to predict the presence of concurrent CDL, and develop a management algorithm that can be easily applied on presentation. METHODS: We conducted a retrospective review of patients presenting with AC to a large tertiary hospital over a 3.5-year period. CDL was defined as common bile duct (CBD) stone(s), sludge, or debris seen on any of the following studies: US, CT, magnetic resonance imaging/MRCP, EUS, ERCP, or intraoperative cholangiogram. A multivariable model to predict CDL was developed on 70% of the patients and validated on the remaining 30%. RESULTS: A total of 366 patients were identified and 65 (17.8%) had concurrent CDL. Univariable analysis was used to predict CDL and demonstrated statistically significant odds ratios for transaminases >3 times the upper limit of normal, alkaline phosphatase (AlkPhos) above normal, lipase >3 times the upper limit of normal, total bilirubin ≥1.8 mg/dL, and CBD diameter >6 mm. In the validation cohort, an optimal model containing alanine transaminase (ALT) >3 times the upper limit of normal, abnormal AlkPhos, and CBD diameter >6 mm was found to have an area under the receiver operating curve of 0.91. When 0 or 1 risk factors were present, 98.6% of patients did not have CDL. When all 3 risk factors were present, 77.8% were found to have CDL. CONCLUSIONS: The prevalence of CDL is high among patients with AC. When a validated model is used, application of cutoffs for ALT, AlkPhos, and CBD diameter can effectively triage patients with low and high likelihood for CDL to surgery or ERCP, respectively.

Detection of Sessile Serrated Adenomas in the Proximal Colon Using Wide-Field Fluorescence Endoscopy.

BACKGROUND & AIMS: Many cancers in the proximal colon develop via from sessile serrated adenomas (SSAs), which have flat, subtle features that are difficult to detect with conventional white-light colonoscopy. Many SSA cells have the V600E mutation in BRAF. We investigated whether this feature could be used with imaging methods to detect SSAs in patients. METHODS: We used phage display to identify a peptide that binds specifically to SSAs, using subtractive hybridization with HT29 colorectal cancer cells containing the V600E mutation in BRAF and Hs738.St/Int cells as a control. Binding of fluorescently labeled peptide to colorectal cancer cells was evaluated with confocal fluorescence microscopy. Rats received intra-colonic 0.0086 mg/kg, 0.026 mg/kg, or 0.86 mg/kg peptide or vehicle and morbidity, mortality, and injury were monitored twice daily to assess toxicity. In the clinical safety study, fluorescently labeled peptide was topically administered, using a spray catheter, to the proximal colon of 25 subjects undergoing routine outpatient colonoscopies (3 subjects were given 2.25 µmol/L and 22 patients were given 76.4 µmol/L). We performed blood cell count, chemistry, liver function, and urine analyses approximately 24 hours after peptide administration. In the clinical imaging study, 38 subjects undergoing routine outpatient colonoscopies, at high risk for colorectal cancer, or with a suspected unresected proximal colonic polyp, were first evaluated by white-light endoscopy to identify suspicious regions. The fluorescently labeled peptide (76.4 µmol/L) was administered topically to proximal colon, unbound peptide was washed away, and white-light, reflectance, and fluorescence videos were recorded digitally. Fluorescence intensities of SSAs were compared with those of normal colonic mucosa. Endoscopists resected identified lesions, which were analyzed histologically by gastrointestinal pathologists (reference standard). We also analyzed the ability of the peptide to identify SSAs vs adenomas, hyperplastic polyps, and normal colonic mucosa in specimens obtained from the tissue bank at the University of Michigan. RESULTS: We identified the peptide sequence KCCFPAQ and measured an apparent dissociation constant of Kd = 72 nM and an apparent association time constant of K = 0.174 min-1 (5.76 minutes). During fluorescence imaging of patients during endoscopy, regions of SSA had 2.43-fold higher mean fluorescence intensity than that for normal colonic mucosa. Fluorescence labeling distinguished SSAs from normal colonic mucosa with 89% sensitivity and 92% specificity. The peptide had no observed toxic effects in animals or patients. In the analysis of ex vivo specimens, peptide bound to SSAs had significantly higher mean fluorescence intensity than to hyperplastic polyps. CONCLUSIONS: We have identified a fluorescently labeled peptide that has no observed toxic effects in animals or humans and can be used for wide-field imaging of lesions in the proximal colon. It distinguishes SSAs from normal colonic mucosa with 89% sensitivity and 92% specificity. This targeted imaging method might be used in early detection of premalignant serrated lesions during routine colonoscopies. ClinicalTrials.gov ID: NCT02156557.

Stent migration following endoscopic suture fixation of esophageal self-expandable metal stents: a systematic review and meta-analysis.

BACKGROUND: Covered self-expandable metal stents (SEMS) are utilized for the management of benign and malignant esophageal conditions; however, covered SEMS are prone to migration. Endoscopic suture fixation may mitigate the migration risk of covered esophageal SEMS. Hence, we conducted a systematic review and meta-analysis to evaluate the effectiveness and safety of endoscopic suture fixation for covered esophageal SEMS. METHODS: Following PRISMA guidelines, we performed a systematic review from 2011 to 2016 to identify studies (case control/case series) reporting the technical success and migration rate of covered esophageal SEMS following endoscopic suture fixation. We searched multiple electronic databases and conference proceedings. We calculated pooled rates (and 95% confidence intervals [CI]) of technical success and stent migration using a random effects model. RESULTS: We identified 14 studies (212 patients) describing covered esophageal SEMS placement with endoscopic suture fixation. When reported, SEMS indications included leak/fistula (n = 75), stricture (n = 65), perforation (n = 10), and achalasia (n = 4). The pooled technical success rate was 96.7% (95% CI 92.3-98.6), without heterogeneity (I 2 = 0%). We identified 29 SEMS migrations at rate of 15.9% (95% CI 11.4-21.6), without heterogeneity (I 2 = 0%). Publication bias was observed, and using the trim-and-fill method, a more conservative estimate for stent migration was 17.0%. Suture-related adverse events were estimated to occur in 3.7% (95% CI 1.6-8.2) of cases. CONCLUSIONS: Endoscopic suture fixation of covered esophageal SEMS appears to reduce stent migration when compared to published rates of non-anchored SEMS. However, SEMS migration still occurs in approximately 1 out of 6 cases despite excellent immediate technical success and low risk of suture-related adverse events.

Specialist Endoscopists Are Associated with a Decreased Risk of Incomplete Polyp Resection During Endoscopic Mucosal Resection in the Colon.

BACKGROUND: Endoscopic experience is known to correlate with outcomes of endoscopic mucosal resection (EMR), particularly complete resection of the polyp tissue. Whether specialist endoscopists can protect against incomplete polypectomy in the setting of known risk factors for incomplete resection (IR) is unknown. AIMS: We aimed to characterize how specialist endoscopists may help to mitigate the risk of IR of large sessile polyps. METHODS: This is a retrospective cohort study of patients who underwent EMR at the University of Michigan from January 1, 2006, to November 15, 2015. The primary outcome was endoscopist-reported polyp tissue remaining at the end of the initial EMR attempt. Specialist endoscopists were defined as endoscopists who receive tertiary referrals for difficult colonoscopy cases and completed at least 20 EMR colonic polyp resections over the study period. RESULTS: A total of 257 patients with 269 polyps were included in the study. IR occurred in 40 (16%) cases. IR was associated with polyp size ≥ 40 mm [adjusted odds ratio (aOR) 3.31, 95% confidence interval (CI) 1.38-7.93], flat/laterally spreading polyps (aOR 2.61, 95% CI 1.24-5.48), and difficulty lifting the polyp (aOR 11.0, 95% CI 2.66-45.3). A specialist endoscopist performing the initial EMR was protective against IR, even in the setting of risk factors for IR (aOR 0.13, 95% CI 0.04-0.41). CONCLUSIONS: IR is associated with polyp size ≥ 40 mm, flat and/or laterally spreading polyps, and difficulty lifting the polyp. A specialist endoscopist initiating the EMR was protective of IR.

The Race-Specific Incidence of Esophageal Squamous Cell Carcinoma in Individuals With Exposure to Tobacco and Alcohol.

OBJECTIVES: The relative impact of esophageal squamous cell carcinoma (ESCC) in minority populations is incompletely understood. We aimed to estimate the race-specific incidences of ESCC and place these in the context of the incidence of esophageal adenocarcinoma (EAC) in white men with gastroesophageal reflux disease (GERD). METHODS: The race- and sex-specific exposures to tobacco and alcohol in the United States were obtained from the National Health Interview Survey. The standardized incidence ratios of exposure to tobacco smoke and/or alcohol for ESCC were estimated from meta-analyses. Existing incidences of ESCC in the United States were obtained from the Surveillance, Epidemiology, and End Results (SEER) program. We then used this data to inform a Markov computer model estimating the incidence of ESCC. RESULTS: The incidence of ESCC reported in SEER was the greatest among African-Americans compared with white non-Hispanics, Hispanics, or Asians. In our model, the estimated incidence of ESCC in African-American men exposed to tobacco and alcohol approached the risk of EAC in white non-Hispanic men with weekly GERD. For instance, at age 60 years, the incidence of ESCC in African-American men who have used both tobacco and alcohol was 30/100,000 compared with an incidence of EAC in white men with GERD of 40/100,000. In comparison, the risk of EAC in white non-Hispanic women with weekly GERD at this age was 6.2/100,000. CONCLUSIONS: The incidence of ESCC in African-American men who use alcohol and tobacco is the highest and comparable to other screened diseases. Development of screening and prevention programs for ESCC in high-risk populations should be considered.

Variation in learning curves and competence for ERCP among advanced endoscopy trainees by using cumulative sum analysis.

BACKGROUND AND AIMS: There are limited data on learning curves and competence in ERCP. By using a standardized data collection tool, we aimed to prospectively define learning curves and measure competence among advanced endoscopy trainees (AETs) by using cumulative sum (CUSUM) analysis. METHODS: AETs were evaluated by attending endoscopists starting with the 26th hands-on ERCP examination and then every ERCP examination during the 12-month training period. A standardized ERCP competency assessment tool (using a 4-point scoring system) was used to grade the examination. CUSUM analysis was applied to produce learning curves for individual technical and cognitive components of ERCP performance (success defined as a score of 1, acceptable and unacceptable failures [p1] of 10% and 20%, respectively). Sensitivity analyses varying p1 and by using a less-stringent definition of success were performed. RESULTS: Five AETs were included with a total of 1049 graded ERCPs (mean ± SD, 209.8 ± 91.6/AET). The majority of cases were performed for a biliary indication (80%). The overall and native papilla allowed cannulation times were 3.1 ± 3.6 and 5.7 ± 4, respectively. Overall learning curves demonstrated substantial variability for individual technical and cognitive endpoints. Although nearly all AETs achieved competence in overall cannulation, none achieved competence for cannulation in cases with a native papilla. Sensitivity analyses increased the proportion of AETs who achieved competence. CONCLUSION: This study demonstrates that there is substantial variability in ERCP learning curves among AETs. A specific case volume does not ensure competence, especially for native papilla cannulation.

Transpapillary drainage has no added benefit on treatment outcomes in patients undergoing EUS-guided transmural drainage of pancreatic pseudocysts: a large multicenter study.

BACKGROUND AND AIMS: The need for transpapillary drainage (TPD) in patients undergoing transmural drainage (TMD) of pancreatic fluid collections (PFCs) remains unclear. The aims of this study were to compare treatment outcomes between patients with pancreatic pseudocysts undergoing TMD versus combined (TMD and TPD) drainage (CD) and to identify predictors of symptomatic and radiologic resolution. METHODS: This is a retrospective review of 375 consecutive patients with PFCs who underwent EUS-guided TMD from 2008 to 2014 at 15 academic centers in the United States. Main outcome measures included TMD and CD technical success, treatment outcomes (symptomatic and radiologic resolution) at follow-up, and predictors of treatment outcomes on logistic regression. RESULTS: A total of 375 patients underwent EUS-guided TMD of PFCs, of which 174 were pseudocysts. TMD alone was performed in 95 (55%) and CD in 79 (45%) pseudocysts. Technical success was as follows: TMD, 92 (97%) versus CD, 35 (44%) (P = .0001). There was no difference in adverse events between the TMD (15%) and CD (14%) cohorts (P = .23). Median long-term (LT) follow-up after transmural stent removal was 324 days (interquartile range, 72-493 days) for TMD and 201 days (interquartile range, 150-493 days) (P = .37). There was no difference in LT symptomatic resolution (TMD, 69% vs CD, 62%; P = .61) or LT radiologic resolution (TMD, 71% vs CD, 67%; P = .79). TPD attempt was negatively associated with LT radiologic resolution of pseudocyst (odds ratio, 0.11; 95% confidence interval, 0.02-0.8; P = .03). CONCLUSIONS: TPD has no benefit on treatment outcomes in patients undergoing EUS-guided TMD of pancreatic pseudocysts and negatively affects LT resolution of PFCs.

The synergistic effects of alcohol and tobacco consumption on the risk of esophageal squamous cell carcinoma: a meta-analysis.

OBJECTIVES: Tobacco and alcohol use are established risk factors for esophageal squamous cell carcinoma (ESCC). We sought to determine whether these factors act synergistically to increase the risk of ESCC. METHODS: We performed a systematic literature search in multiple electronic databases regardless of language. Eligible studies were population-based case-control or cohort studies of ESCC that assessed the effects of tobacco and/or alcohol. Departures from multiplicative effects were quantified by the synergy factor (SF); SF >1 indicates positive synergy. Meta-analyses were performed to estimate summary-adjusted odds ratios (ORs) and the summary crude SF using random-effect models. Heterogeneity was defined by Cochrane's Q P<0.10 and the inconsistency index. RESULTS: Systematic review identified 7,629 unique citations, of which 5 were eligible. Either tobacco or alcohol use was associated with a 20-30% increased risk for ESCC compared with nonuse, but the use of both was associated with an approximately threefold risk for ESCC; the summary-adjusted OR for combined alcohol and tobacco use was 3.28 (95% confidence interval (CI)=2.11, 508; Cochrane's Q P value=0.05; I(2)=55.3%). The summary SF for ever-use of both tobacco and alcohol was 1.85 (95% CI=1.45, 2.38; Cochrane's Q P value=0.49; I(2)=0.0%). CONCLUSIONS: There is a positive synergistic effect of alcohol and tobacco use for ESCC. The observed combined effect of the two factors is almost double if there were no synergy. Efforts for controlling the burden of ESCC should focus on individuals who use both alcohol and tobacco.

KRT17High/CXCL8+ tumor cells display both classical and basal features and regulate myeloid infiltration in the pancreatic cancer microenvironment.

PURPOSE: Pancreatic ductal adenocarcinoma (PDAC) is generally divided in two subtypes, classical and basal. Recently, single cell RNA sequencing has uncovered the co-existence of basal and classical cancer cells, as well as intermediary cancer cells, in individual tumors. The latter remains poorly understood; here, we sought to characterize them using a multimodal approach. EXPERIMENTAL DESIGN: We performed subtyping on a single cell RNA sequencing dataset containing 18 human PDAC samples to identify multiple intermediary subtypes. We generated patient-derived PDAC organoids for functional studies. We compared single cell profiling of matched blood and tumor samples to measure changes in the local and systemic immune microenvironment. We then leveraged longitudinally patient-matched blood to follow individual patients over the course of chemotherapy. RESULTS: We identified a cluster of KRT17-high intermediary cancer cells that uniquely express high levels of CXCL8 and other cytokines. The proportion of KRT17High/CXCL8+ cells in patient tumors correlated with intra-tumoral myeloid abundance, and, interestingly, high pro-tumor peripheral blood granulocytes, implicating local and systemic roles. Patient-derived organoids maintained KRT17High/CXCL8+cells and induced myeloid cell migration in an CXCL8-dependent manner. In our longitudinal studies, plasma CXCL8 decreased following chemotherapy in responsive patients, while CXCL8 persistence portended worse prognosis. CONCLUSIONS: Through single cell analysis of PDAC samples we identified KRT17High/CXCL8+ cancer cells as an intermediary subtype, marked by a unique cytokine profile and capable of influencing myeloid cells in the tumor microenvironment and systemically. The abundance of this cell population should be considered for patient stratification in precision immunotherapy.

EUS-Guided hepaticogastrostomy in a pregnant patient with Roux-en-Y hepaticojejunostomy anatomy.

Video 1EUS-Guided hepaticogastrostomy in a pregnant patient with Roux-en-Y hepaticojejunostomy anatomy.

Simulation Training Improves Trainee Technical Skill and Procedural Attitudes in Endoscopic Gastrostomy Tube Placement.

INTRODUCTION: Percutaneous endoscopic gastrostomy (PEG) tube placement remains a core competency of gastroenterology fellowship, although this procedure is performed infrequently. Some training programs lack sufficient procedural volume for trainees to develop confidence and competence in this procedure. We aimed to determine the impact of a simulation-based educational intervention on trainee technical skill and procedural attitudes in simulated PEG tube placement. METHODS: Gastroenterology fellows were invited to participate in the study. Baseline procedural attitudes toward PEG tube placement (self-confidence, perceived skill level, perceived level of required supervision) were assessed before simulation training using a Likert scale. Baseline technical skills were assessed by video recording-simulated PEG tube placement on a PEG tube simulator with scoring using a procedural checklist. Fellows next underwent individualized simulation training and repeated simulated PEG tube placement until greater than 90% of checklist items were achieved. Procedural attitudes were reassessed directly after the simulation. Technical skill and procedural attitudes were then reassessed 6 to 12 weeks later (delayed posttraining). RESULTS: Twelve fellows completed the study. Simulation training led to significant improvement in technical skill at delayed reassessment (52.9 ± 14.3% vs. 78.0 ± 8.9% correct, P = 0.0002). Simulation training also led to significant immediate improvements in self-confidence (2.1 ± 0.7 vs. 3.1 ± 0.3, P = 0.001), perceived skill level (2.2 ± 1.0 vs. 4 ± 1.1, P < 0.001), and perceived level of required supervision (2.2 ± 0.9 vs. 3.2 ± 0.6, P = 0.003). CONCLUSIONS: Simulation training led to sustained improvements in gastroenterology fellows' technical skill and procedural attitudes in PEG tube placement. Incorporation of simulation curricula in gastroenterology fellowships for this infrequently performed procedure should be considered.

Multimodal Mapping of the Tumor and Peripheral Blood Immune Landscape in Human Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDA) is characterized by an immune-suppressive tumor microenvironment that renders it largely refractory to immunotherapy. We implemented a multimodal analysis approach to elucidate the immune landscape in PDA. Using a combination of CyTOF, single-cell RNA sequencing, and multiplex immunohistochemistry on patient tumors, matched blood, and non-malignant samples, we uncovered a complex network of immune-suppressive cellular interactions. These experiments revealed heterogeneous expression of immune checkpoint receptors in individual patient's T cells and increased markers of CD8+ T cell dysfunction in advanced disease stage. Tumor-infiltrating CD8+ T cells had an increased proportion of cells expressing an exhausted expression profile that included upregulation of the immune checkpoint TIGIT, a finding that we validated at the protein level. Our findings point to a profound alteration of the immune landscape of tumors, and to patient-specific immune changes that should be taken into account as combination immunotherapy becomes available for pancreatic cancer.