Molecular Analysis of Persistent and Recurrent Barrett's Esophagus in the Setting of Endoscopic Therapy.

INTRODUCTION: Early neoplastic progression of Barrett's esophagus (BE) is often treated with endoscopic therapy. Although effective, some patients are refractory to therapy or recur after apparent eradication of the BE. The goal of this study was to determine whether genomic alterations within the treated BE may be associated with persistent or recurrent disease. METHODS: We performed DNA sequencing on pre-treatment esophageal samples from 45 patients who were successfully treated by endoscopic therapy and did not recur as well as pre-treatment and post-treatment samples from 40 patients who had persistent neoplasia and 21 patients who had recurrent neoplasia. The genomic alterations were compared between groups. RESULTS: The genomic landscape was similar between all groups. Patients with persistent disease were more likely to have pre-treatment alterations involving the receptor tyrosine kinase pathway ( P = 0.01), amplifications of oncogenes ( P = 0.01), and deletions of tumor suppressor genes ( P = 0.02). These associations were no longer significant after adjusting for patient age and BE length. More than half of patients with persistent (52.5%) or recurrent (57.2%) disease showed pre-treatment and post-treatment samples that shared at least 50% of their driver mutations. DISCUSSION: Pre-treatment samples were genomically similar between those who responded to endoscopic therapy and those who had persistent or recurrent disease, suggesting there is not a strong genomic component to treatment response. Although it was expected to find shared driver mutations in pre-treatment and post-treatment samples in patients with persistent disease, the finding that an equal number of patients with recurrent disease also showed this relation suggests that many recurrences represent undetected minimal residual disease.

Efficacy and safety of long-term indwelling plastic stents after resolution of pancreatic fluid collections with endoscopic transmural drainage: a systematic review and meta-analysis.

BACKGROUND: Pancreatic fluid collections (PFCs) may recur after resolution with endoscopic transmural drainage (ETD) and standard stent removal (SSR). Herein, we compared the efficacy and safety of leaving long-term indwelling plastic stents (LTIS) vs. standard stent removal after PFC resolution with ETD. METHODS: We performed a systematic review of MEDLINE, EMBASE, CINAHL, Scopus, and Cochrane databases from inception to September 2022. Full-text articles comparing long-term (> 6 months) outcomes of LTIS and SSR were eligible, as well as single-arm studies with ≥ 10 patients with LTIS. Two independent reviewers selected studies, extracted data, and assessed the risk of bias using the Newcastle-Ottawa Scale. Measured outcomes included the following: (A) PFC recurrence; (B) interventions for PFC recurrence; (C) technical success; and (D) adverse events (AEs). Meta-analysis was carried out using random-effects models. RESULTS: We included 16 studies, encompassing 1285 patients. Compared to SSR after PFC resolution with ETD, LTIS was associated with significantly lower risk of PFC recurrence (3% vs. 23%; OR 0.22 [95%CI 0.09-0.52]; I2 = 45%) and need for interventions (2% vs. 14%; OR 0.35 [95%CI 0.16-0.78]; I2 = 0%). The superiority of LTIS on reducing PFC recurrence was found with walled-off necrosis, with or without disconnected pancreatic duct, and with placement of ≥ 2 LTIS. When using LTIS, the pooled proportion of AEs was 8% (95%CI 4-11%) and technical success was 93% (95%CI 86-99%). CONCLUSIONS: Our results show that LTIS after PFC resolution with ETD is feasible, safe, and superior to SSR in reducing the risk of PFC recurrence and need for interventions.

A technique for leaving long-term indwelling double-pigtail plastic stents after resolution of pancreatic fluid collections.

Video 1Demonstration of the endoscopic technique of leaving long-term indwelling plastic stent(s) when a lumen-apposing metal stent is removed after pancreatic fluid collection resolution.

Comparison of lumen-apposing metal stents versus endoscopic balloon dilation for the management of benign colorectal anastomotic strictures.

BACKGROUND AND AIMS: Limited data exist evaluating lumen-apposing metal stents (LAMSs) with endoscopic balloon dilation (EBD) for the treatment of benign colorectal anastomotic strictures (BCASs). This study compares outcomes of both interventions. METHODS: Patients with left-sided BCAS treated with LAMSs versus EBD were identified retrospectively. The primary outcome was a composite of crossover to another intervention to achieve clinical success or recurrence requiring reintervention. RESULTS: Twenty-nine patients (11 LAMS and 18 EBD) were identified with longer follow-up in the EBD group (734 vs 142 days; P = .003). No significant differences were found in the composite outcome, technical success, clinical success, or components of composite outcome. With LAMS, there was a nonsignificant trend toward fewer procedures (2.4 vs 3.3; P = .06) and adverse events (0% vs 16.7%; P = .26). CONCLUSIONS: LAMS appears to be as effective as EBD for the treatment of BCAS but may require fewer procedures and may be safer than EBD.

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.

Flexible fiber cholangioscope for detection of near-infrared fluorescence.

Video 1Flexible fiber cholangioscope for detection of near-infrared fluorescence.

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.

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.

Small Intestinal Bacterial Overgrowth Is Common in Chronic Pancreatitis and Associates With Diabetes, Chronic Pancreatitis Severity, Low Zinc Levels, and Opiate Use.

OBJECTIVES: Small intestinal bacterial overgrowth (SIBO) is often present in patients with chronic pancreatitis (CP) with persistent steatorrhea, despite pancreatic enzyme replacement therapy. Overall prevalence of SIBO, diagnosed by glucose breath test (GBT), varies between 0% and 40% but 0%-21% in those without upper gastrointestinal (GI) surgery. We investigated the prevalence and nonsurgical independent predictors of SIBO in CP without upper GI surgery. METHODS: Two hundred seventy-three patients ≥18 years old had a presumptive diagnosis of CP and a GBT between 1989 and 2017. We defined CP by Mayo score (0-16) ≥4 and a positive GBT for SIBO by Rome consensus criteria and retrospectively collected data for 5 a priori variables (age, opiates, alcohol use, diabetes mellitus (DM), gastroparesis) and 41 investigational variables (demographics, GI symptoms, comorbidities, CP etiologies and cofactors, CP symptom duration, Mayo score and nondiabetes components, and biochemical variables). RESULTS: Ninety-eight of 273 patients had definite CP and 40.8% had SIBO. Five of 46 variables predicted SIBO: opiates, P = 0.005; DM, P = 0.04; total Mayo score, P < 0.05; zinc, P = 0.005; and albumin, P < 0.05). Multivariable analysis of 3 noncorrelated variables identified zinc level (odds ratio = 0.0001; P = 0.03) as the sole independent predictor of SIBO (model C-statistic = 0.89; P < 0.001). DISCUSSION: SIBO, diagnosed by GBT, occurs in 40.8% of patients with CP without upper GI surgery. In patients with CP, markers of more severe CP (low zinc level, DM and increased Mayo score) and opiate use should raise clinical suspicion for SIBO, particularly in patients with persistent steatorrhea or weight loss despite pancreatic enzyme replacement therapy.

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.

Recent advances in understanding and managing acute pancreatitis.

This review highlights advances made in recent years in the diagnosis and management of acute pancreatitis (AP). We focus on epidemiological, clinical, and management aspects of AP. Additionally, we discuss the role of using risk stratification tools to guide clinical decision making. The majority of patients suffer from mild AP, and only a subset develop moderately severe AP, defined as a pancreatic local complication, or severe AP, defined as persistent organ failure. In mild AP, management typically involves diagnostic evaluation and supportive care resulting usually in a short hospital length of stay (LOS). In severe AP, a multidisciplinary approach is warranted to minimize morbidity and mortality over the course of a protracted hospital LOS. Based on evidence from guideline recommendations, we discuss five treatment interventions, including intravenous fluid resuscitation, feeding, prophylactic antibiotics, probiotics, and timing of endoscopic retrograde cholangiopancreatography (ERCP) in acute biliary pancreatitis. This review also highlights the importance of preventive interventions to reduce hospital readmission or prevent pancreatitis, including alcohol and smoking cessation, same-admission cholecystectomy for acute biliary pancreatitis, and chemoprevention and fluid administration for post-ERCP pancreatitis. Our review aims to consolidate guideline recommendations and high-quality studies published in recent years to guide the management of AP and highlight areas in need of research.

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.

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.

Endoscopic suture fixation is associated with reduced migration of esophageal fully covered self-expandable metal stents (FCSEMS).

BACKGROUND: Esophageal fully covered self-expandable metal stents (FCSEMS) are indicated for the management of benign and malignant conditions of the esophagus including perforations, leaks, and strictures. FCSEMS are resistant to tissue ingrowth and are removable; however, stent migration occurs in 30-55% of cases. Endoscopic suture fixation of FCSEMS has been utilized to decrease the risk of stent migration though data supporting this practice remain limited. The primary aim of this study was to compare clinical outcomes and migration rate of patients who underwent placement of esophageal FCSEMS with and without endoscopic suture fixation. METHODS: Our single-center, retrospective, cohort study includes patients who underwent esophageal FCSEMS placement with and without endoscopic suture fixation between January 1, 2012, and November 11, 2015. Baseline patient characteristics, procedural details, and clinical outcomes were abstracted. Logistic regression was performed to identify clinical and technical factors associated with outcomes and stent migration. RESULTS: A total of 51 patients underwent 62 FCSEMS placements, including 21 procedures with endoscopic suture fixation and 41 without. Suture fixation was associated with reduced risk of stent migration (OR 0.13, 95% CI 0.03-0.47). Prior stent migration was associated with significantly higher risk of subsequent migration (OR 6.4, 95% CI 1.6-26.0). Stent migration was associated with lower likelihood of clinical success (OR 0.21, 95% CI 0.06-0.69). There was a trend toward higher clinical success among patients undergoing suture fixation (85.7 vs. 60.9%, p = 0.07). CONCLUSIONS: Endoscopic suture fixation of FCSEMS was associated with a reduced stent migration rate. Appropriate patient selection for suture fixation of FCSEMS may lead to reduced migration in high-risk patients.

Duct Diameter and Size of Stones Predict Successful Extracorporeal Shock Wave Lithotripsy and Endoscopic Clearance in Patients With Chronic Pancreatitis and Pancreaticolithiasis.

OBJECTIVES: The need for endoscopic therapy before extracorporeal shock wave lithotripsy (SWL) to facilitate pancreatic duct stone removal is unclear. Predictive factors associated with successful fragmentation and subsequent complete duct clearance are variable. We hypothesize pancreatic duct strictures and large stones, but not pre-SWL endotherapy, correlate with successful fragmentation and complete duct clearance. METHODS: A retrospective cohort study of patients with pancreaticolithiasis who underwent SWL and endoscopic retrograde cholangiopancreatography between January 2009 and June 2014 was evaluated. RESULTS: Thirty-seven patients were treated. Technical success (TS) of fragmentation was achieved in 22 patients (60%). Technical success was associated with fewer stones and SWL sessions and smaller stone and duct size. By multivariate logistic regression, only duct dilation was associated with TS. Endoscopic success of complete duct clearance was achieved in 29 patients (80%). Endoscopic success was more frequent with stones 12 mm or less and with successful TS. By multivariate logistic regression, stones greater than 12 mm were associated with endoscopic failure. CONCLUSIONS: Pre-SWL endotherapy does not affect stone fragmentation. Patients with a dilated duct (>8 mm) and pancreatic stones 12 mm or greater were associated with unsuccessful TS and endoscopic success, respectively, and may benefit from early referral for surgical decompression.