Enhanced stability of the SARS CoV-2 spike glycoprotein following modification of an alanine cavity in the protein core.

The spike (S) glycoprotein of SARS CoV-2 is the target of neutralizing antibodies (NAbs) that are crucial for vaccine effectiveness. The S1 subunit binds ACE2 while the S2 subunit mediates virus-cell membrane fusion. S2 is a class I fusion glycoprotein subunit and contains a central coiled coil that acts as a scaffold for the conformational changes associated with fusion function. The coiled coil of S2 is unusual in that the 3-4 repeat of inward-facing positions are mostly occupied by polar residues that mediate few inter-helical contacts in the prefusion trimer. We examined how insertion of bulkier hydrophobic residues (Val, Leu, Ile, Phe) to fill a cavity next to Ala1016 and Ala1020 in the 3-4 repeat affects the stability and antigenicity of S trimers. Substitution of Ala1016 with bulkier hydrophobic residues in the context of a prefusion-stabilized S trimer, S2P-FHA, was associated with increased thermal stability. S glycoprotein membrane fusion function was retained with Ala1016/Ala1020 cavity-filling mutations associated with improved recombinant S2P-FHA thermostability, however 2 mutants, A1016L and A1016V/A1020I, lacked ability to mediate entry of S-HIV-1 pseudoparticles into 293-ACE2 cells. When assessed as immunogens, two thermostable S2P-FHA mutants derived from the ancestral isolate, A1016L (16L) and A1016V/A1020I (VI) elicited neutralizing antibody with 50%-inhibitory dilutions (ID50s) in the range 2,700-5,110 for ancestral and Delta-derived viruses, and 210-1,744 for Omicron BA.1. The antigens elicited antibody specificities directed to the receptor-binding domain (RBD), N-terminal domain (NTD), fusion peptide and stem region of S2. The VI mutation enabled the production of intrinsically stable Omicron BA.1 and Omicron BA.4/5 S2P-FHA-like ectodomain oligomers in the absence of an external trimerization motif (T4 foldon), thus representing an alternative approach for stabilizing oligomeric S glycoprotein vaccines.

Location and appearance of dysplastic Barrett's esophagus recurrence after endoscopic eradication therapy: no additional yield from random biopsy sampling neosquamous mucosa.

BACKGROUND AND AIMS: Surveillance after complete remission of intestinal metaplasia (CRIM) is essential. Current recommendations are to sample visible lesions first, followed by random 4-quadrant biopsy sampling of the original Barrett's esophagus (BE) length. To inform post-CRIM surveillance protocols, we aimed to identify the anatomic location, appearance, and histology of BE recurrences. METHODS: We performed an analysis of 216 patients who achieved CRIM after endoscopic eradication therapy for dysplastic BE at a Barrett's Referral Unit between 2008 and 2021. The anatomic location, recurrence histology, and endoscopic appearance of dysplastic recurrences were evaluated. RESULTS: After a median of 5.5 years (interquartile range, 2.9-7.2) of follow-up after CRIM, 57 patients (26.4%) developed nondysplastic BE (NDBE) recurrence and 18 patients (8.3%) developed dysplastic recurrence. From 8158 routine surveillance biopsy samplings of normal-appearing tubular esophageal neosquamous epithelium, the yield for recurrent NDBE or dysplasia was 0%. One hundred percent of dysplastic tubular esophageal recurrences were visible and in BE islands, whereas 77.8% of gastroesophageal junction dysplastic recurrences were nonvisible. Four distinct endoscopic features suspicious for recurrent advanced dysplasia or neoplasia were identified: buried or subsquamous BE, irregular mucosal pattern, loss of vascular pattern, and nodularity or depression. CONCLUSIONS: The yield of routine surveillance biopsy sampling of normal-appearing tubular esophageal neosquamous epithelium was zero. BE islands with indistinct mucosal or loss of vascular pattern, nodularity or depression, and/or signs of buried BE should raise clinician suspicion for advanced dysplasia or neoplasia recurrence. We suggest a new surveillance biopsy sampling protocol with a focus on meticulous inspection, followed by targeted biopsy sampling of visible lesions and random 4-quadrant biopsy sampling of the gastroesophageal junction.

Direct percutaneous endoscopic gastrostomy for nutritional support in patients with aerodigestive tract cancers.

BACKGROUND: Conventional pull-through percutaneous endoscopic gastrostomy (PEG) risks infection and tumour implantation in head and neck cancers. Endoscopically inserted direct gastrostomy has lower rates of complications but is underutilised. AIMS: To describe the endoscopic steps for direct gastrostomy insertion and review our single-centre experience to assess the technical feasibility and safety. METHODS: Patients who underwent endoscopic direct gastrostomy insertion between December 2016 and June 2021 were included. A 24Fr introducer kit for gastrostomy feeding tube (Avanos Healthcare, Australia) was used. Patient and tumour characteristics, procedural data and 30-day outcomes were recorded. RESULTS: Thirty patients underwent direct PEG insertion (mean age 64 years and 24 male). All were planned for or currently undergoing radiotherapy. Twenty-six (87%) of 30 cases were performed under conscious sedation over a median procedure time of 21 min (interquartile range 11 min). No tumour seeding was seen, and one case of PEG-site infection was observed. CONCLUSIONS: Direct PEG is safe and effective and should be considered for patients with aerodigestive tract cancer in need of nutritional support.

Cholesterol-dependent cytolysins: The outstanding questions.

The cholesterol-dependent cytolysins (CDCs) are a major family of bacterial pore-forming proteins secreted as virulence factors by Gram-positive bacterial species. CDCs are produced as soluble, monomeric proteins that bind specifically to cholesterol-rich membranes, where they oligomerize into ring-shaped pores of more than 30 monomers. Understanding the details of the steps the toxin undergoes in converting from monomer to a membrane-spanning pore is a continuing challenge. In this review we summarize what we know about CDCs and highlight the remaining outstanding questions that require answers to obtain a complete picture of how these toxins kill cells.

Quality of upper GI endoscopy: a prospective cohort study on impact of endoscopist education.

BACKGROUND AND AIMS: Guidelines on quality of upper GI (UGI) endoscopy have been proposed by the British Society of Gastroenterology (BSG) and European Society of Gastrointestinal Endoscopy (ESGE). However, these guidelines have not been evaluated in clinical practice. We aimed to measure the impact of endoscopist education on the quality of gastroscopy based on these guidelines and the association between compliance with guidelines and the detection of clinically significant premalignant pathology such as Barrett's esophagus (BE), esophageal squamous dysplasia, gastric intestinal metaplasia (GIM), and Helicobacter pylori. METHODS: Endoscopists participated in a 1-hour education session on recommended performance measures and endoscopic detection of premalignant pathologies. A controlled before and after study was performed, measuring compliance with guidelines and rates of detection of pathology in control and intervention groups. RESULTS: Over 2 years, 2719 procedures were performed: 1412 in the control group and 1307 in the intervention group. The proportion of procedures complying with guidelines was higher in the intervention group. The use of biopsy sampling protocols (eg, management of precancerous conditions of the stomach, 52% vs 91%; P = .007) and standardized terminology (eg, Forrest classification, 24% vs 68%; P < .001) was significantly higher. Detection of H pylori was higher in the intervention group (5.5% vs 9.8%, P = .003). Minimum inspection time of 7 minutes was associated with detection of BE (7.4% vs 2.0%, P < .001). CONCLUSIONS: A simple endoscopist education session enhanced the quality of UGI endoscopy by improving compliance with BSG and ESGE recommendations and increasing the detection of clinically significant pathology. A minimum inspection time of 7 minutes was associated with increased diagnostic yield and may be a feasible quality indicator for clinical practice.

Evaluation of Endoscopic Practices and Outcomes in Follow-up of Gastric Ulcers.

GOAL: The aim of this study was to evaluate current practice in gastric ulcer follow-up to establish diagnostic yield and predictors of malignancy. BACKGROUND: Repeat gastroscopy is routinely performed to confirm gastric ulcer healing and exclude malignancy. However, the incidence of malignancy at follow-up endoscopy is low, without consensus regarding case selection and timing. STUDY: New gastric ulcers diagnosed on gastroscopy at 2 institutions in Australia were identified through keyword search of endoscopy reports over a 5-year period (2013 to 2017). Data collected included patient demographics, clinical presentation, and endoscopic and histologic findings from initial and subsequent gastroscopies. RESULTS: Of 795 patients, repeat gastroscopy was performed in 440 (55%). Malignancy was diagnosed in 52 (7%) with 83% identified at initial gastroscopy. Eight cancers were identified at repeat gastroscopy with malignancy yield of 2% (8/440). Three were diagnosed in patients with benign initial ulcer histology (3/286, 1%). One cancer was diagnosed during follow-up in a patient with benign histology but no repeat gastroscopy (1/286, 0.3%). Predictors of benign ulcers were absence of endoscopic suspicion [odds ratio (OR) 0.1 (0.03-0.13), P≤0.005], complete healing on repeat gastroscopy [OR 0.5 (0.34-0.70), P=0.036] and benign initial histology [OR 0.12 (0.43-0.90), P≤0.005]. CONCLUSIONS: Seven percent of new gastric ulcers were malignant with most identified with biopsy on initial gastroscopy. Malignancy yield from follow-up gastroscopy was 2%. Diagnostic yield of endoscopic follow-up may be low in ulcers with benign appearance and adequate histology. However, current practice of repeat gastroscopy is warranted in the absence of patient-based and lesion-based predictors of malignancy.

Endoscopic features of buried Barrett's mucosa.

BACKGROUND AND AIMS: Buried Barrett's mucosa is defined as intestinal metaplasia that is "buried" under the normal-appearing squamous epithelium. This can occur in Barrett's esophagus with or without previous endoscopic therapy. Dysplasia and neoplasia within buried Barrett's mucosa have also been reported. However, endoscopic features of buried Barrett's mucosa have not been described. At our tertiary referral center for Barrett's esophagus, several endoscopic features have been observed in patients who were found to have buried Barrett's mucosa on histology. These features are squamous epithelium which is (1) darker pink on white-light and darker brown on narrow-band imaging and/or (2) has a slightly raised or nodular appearance. It was also observed that either of these 2 features is frequently seen adjacent to a Barrett's mucosa island. This study aimed to (1) evaluate the diagnostic accuracy of these endoscopic features, and (2) evaluate the frequency of endoscopically identifiable buried Barrett's mucosa in patients with dysplastic Barrett's esophagus, before and after endoscopic eradication therapy. METHODS: This was a retrospective analysis of a prospectively observed cohort of all cases of dysplastic Barrett's esophagus referred to St Vincent's Hospital, Melbourne. Endoscopy documentation software and histopathology reports of esophageal biopsy and EMR specimens between March 2013 and March 2019 were searched for terms "buried" or "subsquamous" Barrett's mucosa. Endoscopic reports, images, and histopathology reports of suspected buried Barrett's mucosa were then reviewed to apply the endoscopic features and correlate with the histologic diagnosis. RESULTS: In a cohort of 506 patients with dysplastic Barrett's esophagus, 33 (7%) patients (73% male, median age at referral 70.5 years) had buried Barrett's mucosa on histology. Twenty-seven (82%) patients had previous treatment for dysplastic Barrett's esophagus; radiofrequency in 2 (6%), EMR in 4 (12%), and both modalities in 21 (64%). Six (18%) had no previous treatment. Histologically confirmed buried Barrett's mucosa was suspected at endoscopy in 26 patients (79%). Endoscopic features were (1) darker pink or darker brown mucosa underneath squamous epithelium (24%), (2) raised areas underneath squamous mucosa (27%), and both features present concurrently (27%). These features were associated with adjacent islands of Barrett's esophagus in 48%. Forty-four cases of buried Barrett's mucosa were suspected endoscopically, and these were sampled by biopsy (50%) and EMR (50%). Buried Barrett's mucosa was confirmed in 26 cases, with a positive predictive value of endoscopic suspicion of 59%. Eighteen cases of endoscopically suspected buried Barrett's mucosa had no buried Barrett's mucosa on histology; inflammation or reflux was identified in 12 (67%) patients. Dysplasia was identified within buried Barrett's mucosa in 12 (36%) patients; 5 intramucosal adenocarcinoma, 1 high-grade dysplasia, and 6 low-grade dysplasia. Endoscopic features of buried Barrett's mucosa were observed in 11 of 12 cases harboring dysplasia or neoplasia, compared with 15 of 21 cases of buried Barrett's mucosa without dysplasia. CONCLUSIONS: In this retrospective analysis of prospectively observed patients with dysplastic Barrett's esophagus, buried Barrett's mucosa was identified in 7%, including treatment-naive patients. The proposed endoscopic features of buried Barrett's mucosa were seen in 79% of patients with histology confirmed disease. These endoscopic features may predict the presence of buried Barrett's mucosa, which may contain dysplasia or neoplasia. An overlap between the endoscopic features of inflammation, reflux, and buried Barrett's mucosa was observed. Future prospective studies are required to develop and validate endoscopic criteria for identifying buried Barrett's mucosa.

Quantifying early gastric cancer in Australia: What is the opportunity for gastric endoscopic submucosal dissection?

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) is the recommended treatment for early gastric cancer (EGC). However, there are challenges in attaining expertise in ESD in countries where the incidence of gastric cancer and proportion diagnosed at an early stage of disease are relatively low. This study aims to establish the proportion of gastric cancer meeting histological criteria for EGC, which may be suitable for ESD, in a Western population. METHODS: Gastric cancers reported to the Victorian Cancer Registry between January 2011 and December 2016 were analyzed. EGC was defined as tumor confined to mucosa (T1a) or submucosa (T1b). Histology reports were analyzed using Japanese and European guidelines to identify potential ESD candidates. Criteria for extended ESD were based on grade of differentiation, tumor depth, lymphovascular and perineural invasion, and ulceration. RESULTS: Twenty percent of 1217 gastric cancers was EGC (237 cases), with detailed histopathology reports suitable for evaluating ESD criteria recorded in 182 cases. Standard and extended ESD criteria were met in 46% (84/182) and 75% (132/182), respectively. Actual treatment of the 237 EGC was endoscopic in 14% (n = 33) and surgery in 86% (n = 204). Endoscopically treated EGCs were more likely to be stage T1a and located in the proximal stomach. CONCLUSIONS: EGCs represented 20% of reported gastric adenocarcinomas with the majority fulfilling criteria for ESD. ESD should be considered in the management algorithm and discussed at tumor board meetings involving interventional endoscopists. To increase utilization of ESD, systems need to be implemented to improve training, accreditation, and access to ESD.

Efficacy of drug and endoscopic treatment of Crohn's disease strictures: A systematic review.

BACKGROUND AND AIMS: Strictures are the commonest complication in Crohn's disease. Surgery and endoscopic dilation are the mainstays of treatment, while drug therapy has often been considered contraindicated. The benefit of nonsurgical treatments, particularly drug and endoscopic therapy, need to be defined. METHODS: Ovid MEDLINE, Embase, Emcare, PsycINFO, CINAHL and the Cochrane Library (inception until August 30, 2019) were searched. Studies with ≥ 10 patients with Crohn's disease strictures, reporting on outcomes following medication or endoscopic treatment, were included. RESULTS: Of 3480 records, 85 studies met inclusion criteria and formed the basis of this analysis. Twenty-five studies assessed drug therapy; none were randomized trials. Despite study heterogeneity anti-tumor necrosis factor (TNF) therapy appeared effective, with 50% of patients avoiding surgery after 4 years of follow up. No other drug therapy was of demonstrable benefit. Sixty studies assessed endoscopic therapy including 56 on endoscopic balloon dilation, two assessed needle knife stricturotomy, and two stent insertion. Dilation was equally effective for de novo and anastomotic strictures ≤ 5 cm in length, with most studies reporting a subsequent surgical rate of 30% to 50%. Repeat dilation was required in approximately half of all patients. CONCLUSIONS: Anti-TNF drug therapy and endoscopic balloon dilation are effective strategies for avoiding surgery in patients with stricturing Crohn's disease. Additional endoscopic therapies require further evaluation. Early data suggest that combining these therapies may provide greater benefit than individual therapies. Optimization of current drug and endoscopic therapy, and the incorporation of newer therapies, are needed for stricturing Crohn's disease.

An Endoscopic Transluminal Approach, Compared With Minimally Invasive Surgery, Reduces Complications and Costs for Patients With Necrotizing Pancreatitis.

BACKGROUND & AIMS: Infected necrotizing pancreatitis is a highly morbid disease with poor outcomes. Intervention strategies have progressed from open necrosectomy to minimally invasive approaches. We compared outcomes of minimally invasive surgery vs endoscopic approaches for patients with infected necrotizing pancreatitis. METHODS: We performed a single-center, randomized trial of 66 patients with confirmed or suspected infected necrotizing pancreatitis who required intervention from May 12, 2014, through March 24, 2017. Patients were randomly assigned to groups that received minimally invasive surgery (laparoscopic or video-assisted retroperitoneal debridement, depending on location of collection, n = 32) or an endoscopic step-up approach (transluminal drainage with or without necrosectomy, n = 34). The primary endpoint was a composite of major complications (new-onset multiple organ failure, new-onset systemic dysfunction, enteral or pancreatic-cutaneous fistula, bleeding and perforation of a visceral organ) or death during 6 months of follow-up. RESULTS: The primary endpoint occurred in 11.8% of patients who received the endoscopic procedure and 40.6% of patients who received the minimally invasive surgery (risk ratio 0.29; 95% confidence interval 0.11-0.80; P = .007). Although there was no significant difference in mortality (endoscopy 8.8% vs surgery 6.3%; P = .999), none of the patients assigned to the endoscopic approach developed enteral or pancreatic-cutaneous fistulae compared with 28.1% of the patients who underwent surgery (P = .001). The mean number of major complications per patient was significantly higher in the surgery group (0.69 ± 1.03) compared with the endoscopy group (0.15 ± 0.44) (P = .007). The physical health scores for quality of life at 3 months was better with the endoscopic approach (P = .039) and mean total cost was lower ($75,830) compared with $117,492 for surgery (P = .039). CONCLUSIONS: In a randomized trial of 66 patients, an endoscopic transluminal approach for infected necrotizing pancreatitis, compared with minimally invasive surgery, significantly reduced major complications, lowered costs, and increased quality of life. Clinicaltrials.gov no: NCT02084537.

Magnetic resonance enterography for predicting the clinical course of Crohn's disease strictures.

BACKGROUND AND AIMS: Strictures are the most common Crohn's disease complication, but their natural history is unknown. This study aimed to characterize inflammation, predict prognosis, and understand the impact of drug therapy using magnetic resonance enterography (MRE). METHODS: Patients with a stricture diagnosed on MRE over a 5-year period were reviewed for MRE disease extent and inflammation, clinical course, C-reactive protein, response to anti-TNF therapy, endoscopic dilatation, hospitalization, and surgery. RESULTS: 136 patients had 235 strictures (77, one and 59, ≥ 2 strictures). TREATMENT: 46% of patients underwent surgery after a median 6 months; median follow-up for those not requiring surgery was 41 months. Predictors of surgery: Hospitalization because of obstruction predicted subsequent surgery (OR 2.50; 95% CI 1.06-5.90) while anti-TNF therapy commenced at stricture diagnosis was associated with a reduced risk (OR 0.23; 95% CI 0.05-0.99). MRE characteristics associated with surgery were proximal bowel dilatation ≥ 30-mm diameter (OR 2.98; 95% CI 1.36-6.55), stricture bowel wall thickness ≥ 10-mm (OR 2.42; 95% CI 1.11-5.27), and stricture length > 5-cm (OR 2.56; 95% CI 1.21-5.43). 81% of patients with these three adverse MRE features required surgery versus 17% if none were present (P < 0.001). Accuracy for these three MRE variables predicting surgery was high (AUC 0.76). CONCLUSION: Magnetic resonance enterography findings in Crohn's disease strictures are highly predictive of the disease course and the need for future surgery. MRE may also identify who would benefit from treatment intensification. Anti-TNF therapy is associated with reduced risk of surgery and appears to alter the natural history of this complication.

The impact of multiple low-level BCR-ABL1 mutations on response to ponatinib.

The third-generation tyrosine kinase inhibitor (TKI) ponatinib shows activity against all common BCR-ABL1 single mutants, including the highly resistant BCR-ABL1-T315I mutant, improving outcome for patients with refractory chronic myeloid leukemia (CML). However, responses are variable, and causal baseline factors have not been well-studied. The type and number of low-level BCR-ABL1 mutations present after imatinib resistance has prognostic significance for subsequent treatment with nilotinib or dasatinib as second-line therapy. We therefore investigated the impact of low-level mutations detected by sensitive mass-spectrometry before ponatinib initiation (baseline) on treatment response in 363 TKI-resistant patients enrolled in the PONATINIB for Chronic Myeloid Leukemia Evaluation and Ph(+)Acute Lymphoblastic Leukemia trial, including 231 patients in chronic phase (CP-CML). Low-level mutations were detected in 53 patients (15%, including low-level T315I in 14 patients); most, however, did not undergo clonal expansion during ponatinib treatment and, moreover, no specific individual mutations were associated with inferior outcome. We demonstrate however, that the number of mutations detectable by mass spectrometry after TKI resistance is associated with response to ponatinib treatment and could be used to refine the therapeutic approach. Although CP-CML patients with T315I (63/231, 27%) had superior responses overall, those with multiple mutations detectable by mass spectrometry (20, 32%) had substantially inferior responses compared with those with T315I as the sole mutation detected (43, 68%). In contrast, for CP-CML patients without T315I, the inferior responses previously observed with nilotinib/dasatinib therapy for imatinib-resistant patients with multiple mutations were not seen with ponatinib treatment, suggesting that ponatinib may prove to be particularly advantageous for patients with multiple mutations detectable by mass spectrometry after TKI resistance.

Prognosis for patients with CML and >10% BCR-ABL1 after 3 months of imatinib depends on the rate of BCR-ABL1 decline.

In chronic myeloid leukemia (CML) patients, a breakpoint cluster region-Abelson (BCR-ABL1) value >10% at 3 months of therapy is statistically associated with poorer outcome, yet many of these patients still achieve satisfactory outcomes. We investigated 528 first-line imatinib-treated patients to determine whether patients with the poorest outcome can be better discriminated at 3 months. All outcomes were significantly superior for the 410 patients with BCR-ABL1 ≤10% at 3 months (P < .001). However, the poorest outcomes among the 95 evaluable patients with BCR-ABL1 >10% at 3 months were identified by the rate of BCR-ABL1 decline from baseline, assessed by estimating the number of days over which BCR-ABL1 halved. Patients with BCR-ABL1 halving time <76 days (n = 74) had significantly superior outcomes compared with patients whose BCR-ABL1 values did not halve by 76 days (n = 21; 4-year overall survival, 95% vs 58%, P = .0002; progression-free survival, 92% vs 63%, P = .008; failure-free survival, 59% vs 6%, P < .0001; and major molecular response, 54% vs 5%, P = .008). By multivariate analysis, the halving time was an independent predictor of outcome in this poor risk group. Our study highlighted that the rate of BCR-ABL1 decline may be a critical prognostic discriminator of the patients with very poor outcome among those >10% at 3 months. The International Randomized IFN vs STI571 (IRIS) trial was registered at http://www.clinicaltrials.gov as #NCT00006343. The Tyrosine Kinase Inhibitor Optimization and Selectivity (TOPS) trial was registered at http://www.clinicaltrials.gov as #NCT00124748. The Therapeutic Intensification in DE-novo Leukaemia (TIDEL) I trial was registered at http://www.ANZCTR.org.au as #ACTRN12607000614493. The TIDEL II trial was registered at http://www.ANZCTR.org.au as #ACTRN12607000325404.

Biliary drainage: role of EUS guidance.

BACKGROUND AND AIMS: EUS-guided biliary drainage is a technique being increasingly used when ERCP fails, and it has been the focus of multiple studies and investment in recent years. However, the proportion of cases for which it is really indicated has not been established. The aim of this study is to determine how often EUS-guided biliary drainage is needed in a tertiary-care level therapeutic endoscopy unit. METHODS: This is a prospective cohort study at a single tertiary-care center with a high volume of therapeutic endoscopy. A thousand consecutive ERCPs performed from November 1, 2013 to September 12, 2014 were screened, and those with previous biliary intervention were excluded (n = 476). EUS-guided biliary drainage was performed in suitable patients with failed ERCP and malignant biliary obstruction. The main outcome measures were the rates of ERCP failure and EUS-guided biliary drainage. RESULTS: A total of 524 native papilla ERCPs were performed (41.2% male; median age 60 years, range 6-97 years; 9.4% outside failed ERCP; 1.9% surgically altered anatomy). The ampulla was reached in 518 (98.9%) and not reached in 6 (1.1%) because of surgically altered anatomy (n = 2), malignant duodenal stenosis (n = 3), or both (n = 1). The overall ERCP failure rate was 1.7% (9/524). Cannulation was successful in 99.4% (515/518) and unsuccessful in 0.6% (3/518) of cases in which the ampulla was reached. EUS-guided biliary drainage was indicated in 0.6% (3/524) of all referred native papilla ERCPs, or 33% (3/9) of those patients with failed ERCP; EUS-biliary drainage was successful in all cases. CONCLUSIONS: In a tertiary-care center, use of advanced ERCP techniques results in a high technical success rate. EUS-guided biliary drainage was required in only 0.6% of native papilla ERCPs, and although a number of excellent indications exist, it should not replace good ERCP technique.

Intraprocedural increase in heart rate during EUS-guided celiac plexus neurolysis: Clinically relevant or just a physiologic change?

BACKGROUND AND AIMS: Although EUS-guided celiac plexus neurolysis (EUS-CPN) is performed frequently for palliation of pain in pancreatic cancer, response to treatment is variable. Although intraprocedural increases in heart rate during alcohol injection are observed frequently, their significance and relationship to treatment outcome are unknown. The objective of this study was to examine whether a correlation exists between an increase in heart rate and treatment outcomes in patients undergoing EUS-CPN for pain relief in pancreatic cancer. METHODS: This is a prospective observational study of patients with abdominal pain caused by inoperable pancreatic cancer who underwent EUS-CPN. Heart rate change was defined as an increase of ≥15 beats per minute (bpm) for ≥30 seconds during alcohol injection. Main outcome measures were to compare pain, quality of life, opioid use, and survival between heart rate change and no-change groups. RESULTS: Heart rate change was observed in 25 of 51 patients (49.0%) who underwent EUS-CPN over a 12-month period. Although the heart rate change cohort had significantly better adjusted scores for pain (60 vs 73; P = .042) and components of quality of life such as nausea and/or vomiting (65 vs 81; P = .004), financial difficulties (41 vs 57; P = .02), weight loss (45 vs 65; P = .007), and satisfaction with body image (52 vs 62; P = .035), there was no significant difference in postprocedural opioid use or survival between groups. CONCLUSIONS: Because patients with an increase in intraprocedural heart rate experienced significant improvement in pain and quality of life components, this observation must be further explored in order to improve the technique and outcomes of EUS-CPN.

Endoscopic ultrasonography is not required for staging malignant esophageal strictures that preclude the passage of a diagnostic gastroscope.

BACKGROUND AND AIM: Endoscopic ultrasound (EUS) is considered the most sensitive modality for local staging of esophageal cancer (ECA) and current guidelines recommend EUS in all patients with non-metastatic disease. Our aim was to identify a subset of patients with stenotic, non-metastatic ECA who will not benefit from staging EUS. METHODS: This multicenter study evaluated consecutive patients with newly diagnosed non-metastatic ECA referred for local staging by EUS. All patients had endoscopic evaluation of malignant strictures with 9.8/9.9-mm diagnostic gastroscope prior to EUS. Main outcome measure was to evaluate the relationship between degree of malignant stenosis and tumor staging by EUS. RESULTS: Of 100 patients (median age, 65 years; male 81%), gastroscope could not be advanced past the stricture in 46, all of whom (100%) had locally advanced disease at EUS: T3N0/N+ in 39 and T4N0/N+ in seven. Echoendoscope could not traverse the stricture in any of these patients. Gastroscope could be advanced through the stricture in 54 patients in whom EUS staging was T1N0 in five, T2N0/N+ in eight and T3N0/N+ in 41; echoendoscope could not pass through the stricture in 24 of these 54 (44.4%) patients, all of whom had T3N0/N+ disease. On logistic regression analysis, inability to pass a gastroscope through the stricture was significantly associated with advanced (T3/4) tumor stage (OR = 28.7, 95% CI = 1.64-501.2; P = 0.021). CONCLUSION: Routine EUS examination may not be required in all patients with ECA as the inability to advance a diagnostic gastroscope past a malignant stricture correlates 100% with locally advanced disease on EUS.

Prophylactic endoscopic coagulation to prevent bleeding after wide-field endoscopic mucosal resection of large sessile colon polyps.

BACKGROUND & AIMS: Clinically significant postendoscopic mucosal resection bleeding (CSPEB) is the most frequent significant complication of wide-field endoscopic mucosal resection (WF-EMR) of advanced mucosal neoplasia (sessile or laterally spreading colorectal lesions > 20 mm). CSPEB requires resource-intensive management and there is no strategy for preventing it. We investigated whether prophylactic endoscopic coagulation (PEC) reduces the incidence of CSPEB. METHODS: We performed a prospective randomized controlled trial of 347 patients (mean age, 67.1 y; 55.3% with proximal colonic lesions) undergoing WF-EMR for advanced mucosal neoplasia at 3 Australian tertiary referral centers. Patients were assigned randomly (1:1) to groups receiving PEC (n = 172) or no additional therapy (n = 175, controls). PEC was performed with coagulating forceps, applying low-power coagulation to nonbleeding vessels in the resection defect. CSPEB was defined as bleeding requiring admission to the hospital. The primary end point was the proportion of CSPEB. RESULTS: Patients in each group were similar at baseline. CSPEB occurred in 9 patients receiving PEC (5.2%) and 14 controls (8.0%; P = .30). CSPEB was associated significantly with proximal colonic location on multivariate analysis (odds ratio, 3.08; P = .03). Compared with the proximal colon, there was a significantly greater number (3.8 vs 2.1; P = .002) and mean size (0.5-1 vs 0.3-0.5 mm; P = .04) of visible vessels in the distal colon. CONCLUSIONS: PEC does not significantly decrease the incidence of CSPEB after WF-EMR. There were significantly more and larger vessels in the WF-EMR mucosal defect of distal colonic lesions, yet CSPEB was more frequent with proximal colonic lesions. ClinicalTrials.gov NCT01368731.

Early molecular response and female sex strongly predict stable undetectable BCR-ABL1, the criteria for imatinib discontinuation in patients with CML.

Recent studies have demonstrated that some patients with chronic myeloid leukemia (CML) can maintain remission after discontinuation of imatinib. A prerequisite is stable, undetectable BCR-ABL1. It is not known how many patients achieve this response or the factors associated with its achievement. We examined 423 de novo imatinib-treated patients to determine the cumulative incidence of achieving the discontinuation criteria as defined in the CML8 study (≥2 years of undetectable BCR-ABL1 [Stable MR(4.5)]), and predictive factors. After 8 years of imatinib, the cumulative incidence of Stable MR(4.5) was 36.5%. Therefore, 9% to 15% of first-line imatinib-treated patients would maintain remission after discontinuation. The BCR-ABL1 level at 3 months and factors at diagnosis were examined for association with Stable MR(4.5): Sokal risk, age, sex, and assigned imatinib dose. The only independent predictors were female sex (54.4% vs 27.2%; P = .018) and the 3-month BCR-ABL1 (P < .001). The highest cumulative incidence of Stable MR(4.5) after 8 years was 78.2% for patients with BCR-ABL1 ≤ 0.10%(IS) at 3 months (n = 38). Time to major molecular response (MMR) influenced the time to reach Stable MR(4.5) (P < .001), suggesting slower dynamics of response with a delayed MMR. The findings justify the focus on rapid reduction of BCR-ABL1 as a strategy to maximize potential suitability for imatinib discontinuation studies. The Iris trial was registered at http://www.clinicaltrials.gov as NCT00006343. The Tops trial was registered at http://www.clinicaltrials.gov as NCT00124748. The TIDEL I trial was registered at www.ANZCTR.org.au as ACTRN12607000614493. The TIDEL II trial was registered at www.ANZCTR.org.au as ACTRN12607000325404.

Development and evaluation of a 3D printed endoscopic ampullectomy training model (with video).

BACKGROUND: Endoscopic ampullectomy is a technically challenging, high-risk procedure with limited training opportunities. Although simulation models can assist with endoscopic skill acquisition, an ampullectomy model does not currently exist. OBJECTIVE: To develop a training model that can be used to improve technical skills, knowledge, and confidence in performing endoscopic ampullectomy. DESIGN: Experimental study. SETTING: Tertiary hospital innovation laboratory. SUBJECTS: Twenty-one endoscopists attending an endoscopic resection workshop. INTERVENTIONS: A prototype for endoscopic ampullectomy was created by computer-aided design and 3-dimensional printing of an ampullary mount and base to which a chicken heart was attached and inserted into a silicone stomach-duodenum model. Study participants performed an ampullectomy and evaluated the prototype with a pre- and postampullectomy questionnaire by using a scale of 1 to 5 (very low to very high). MAIN OUTCOME MEASUREMENTS: Evaluation of core procedural steps, technical and visual realism, and proceduralist technical knowledge and confidence. RESULTS: Sixteen endoscopists participated in the study. All core procedural steps were completed by 14 participants. The mean overall technical and visual realism scores were 3.1 (standard deviation [SD], 0.9) and 3.2 (SD, 0.9), respectively. Ten participants (10/15, 66.7%) thought that their technical knowledge had improved, and 11 thought that it would increase further with additional sessions (11/15, 73.3%). Mean confidence score before and after using the model was 2.2 (SD, 1.2) and 2.9 (SD, 1.1), respectively (P=.132). LIMITATIONS: Pilot study, lack of follow-up of participants' endoscopic practice after model experience. CONCLUSION: Although further studies are necessary for validation, this novel prototype appears useful for endoscopic ampullectomy training.

Early metal stent insertion fails to prevent stricturing after single-stage complete Barrett's excision for high-grade dysplasia and early cancer.

BACKGROUND: Barrett's esophagus with high-grade dysplasia (HGD) or intramucosal adenocarcinoma (IMC) can be effectively treated by single-session EMR, resulting in complete Barrett's excision (CBE). CBE provides accurate histology for staging and clinical confirmation of neoplasia eradication but is limited by a high risk of esophageal stricture formation. OBJECTIVE: To evaluate the effectiveness of prophylactic temporary esophageal stenting to prevent post-CBE stricture formation. DESIGN AND SETTING: Single-center, investigator-initiated feasibility study. PATIENTS: Circumferential, short-segment Barrett's esophagus (≤C3≤M5) with HGD or IMC. INTERVENTION: Single-stage CBE and insertion of a fully covered metal esophageal stent at 10 days that was removed at 8 weeks. Patients were followed for a minimum of 2 surveillance endoscopies. MAIN OUTCOME MEASUREMENT: Symptomatic esophageal stricture formation. RESULTS: At the end of the follow-up period, 8 patients (57.1%) required esophageal dilation for symptomatic CBE-related (n = 7) or stent-related (n = 4) strictures. A median of 3 surveillance endoscopies were performed over a median endoscopic follow-up of 17 months (range 4-25 months). Single-stage CBE successfully eliminated Barrett's intestinal metaplasia and neoplasia in 71.4% and 92.9% of patients, respectively. Four patients were admitted to the hospital, and 4 patients had early stent removal because of pain or dysphagia. LIMITATIONS: Single-center feasibility study. CONCLUSIONS: In a prospective study evaluating prophylactic esophageal stent insertion after single-stage CBE, esophageal strictures formed in more than of half the study cohort, and stents were associated with significant morbidity. An alternative method to reduce stricture formation is required. ( CLINICAL TRIAL REGISTRATION NUMBER: NCT01554280.).