Comparison of clinical outcomes among different endoscopic resection methods for treating colorectal neoplasia

BACKGROUND/AIM

Endoscopic treatments of colorectal neoplasms have yet to be standardized. This study aimed to compare efficacy and tolerability of different endoscopic resection methods for colorectal epithelial tumors.

METHODS

Patients with non-pedunculated colorectal tumors undergoing endoscopic treatments were consecutively enrolled, and their medical records were reviewed retrospectively. The resection methods were classified into three groups: endoscopic mucosal resection with circumferential precutting (EMR-P), endoscopic submucosal dissection with snaring (ESD-S), and endoscopic submucosal dissection alone (ESD). We compared en bloc resection, pathological complete resection, and complications associated with these methods.

RESULTS

Overall, 206 lesions from 203 patients were included in the study (mean size 25.2 ± 10.1 mm). The number of lesions treated with EMR-P, ESD-S, and ESD was 91 (44.2 %), 57 (27.7 %), and 58 (28.2 %), respectively. There was a significant difference in both the en bloc resection rates (EMR-P, 61.5 %; ESD-S, 64.9 %; ESD, 96.6 %; p = 0.001) and complete resection rates (EMR-P, 51.6 %; ESD-S, 54.4 %; ESD, 75.9 %; p = 0.009). Bleeding and perforation were less frequently observed in the EMR-P group. In the subgroup-analysis of lesions less than 20 mm, however, these differences were not observed.

CONCLUSIONS

All endoscopic resection methods, including EMR-P, ESD-S, and ESD, were effective and safe for the treatment of colorectal neoplasms. Technically demanding ESD with high en bloc and complete resection rate should be reserved for the suspicious cancer lesion, which requires the precise histological evaluation. EMR-P with good feasibility can be considered an alternative to ESD for the lesions less than 20 mm.

Comparison of clinical outcomes among different endoscopic resection methods for treating colorectal neoplasia

BACKGROUND/AIM

Endoscopic treatments of colorectal neoplasms have yet to be standardized. This study aimed to compare efficacy and tolerability of different endoscopic resection methods for colorectal epithelial tumors.

METHODS

Patients with non-pedunculated colorectal tumors undergoing endoscopic treatments were consecutively enrolled, and their medical records were reviewed retrospectively. The resection methods were classified into three groups: endoscopic mucosal resection with circumferential precutting (EMR-P), endoscopic submucosal dissection with snaring (ESD-S), and endoscopic submucosal dissection alone (ESD). We compared en bloc resection, pathological complete resection, and complications associated with these methods.

RESULTS

Overall, 206 lesions from 203 patients were included in the study (mean size 25.2 ± 10.1 mm). The number of lesions treated with EMR-P, ESD-S, and ESD was 91 (44.2 %), 57 (27.7 %), and 58 (28.2 %), respectively. There was a significant difference in both the en bloc resection rates (EMR-P, 61.5 %; ESD-S, 64.9 %; ESD, 96.6 %; p = 0.001) and complete resection rates (EMR-P, 51.6 %; ESD-S, 54.4 %; ESD, 75.9 %; p = 0.009). Bleeding and perforation were less frequently observed in the EMR-P group. In the subgroup-analysis of lesions less than 20 mm, however, these differences were not observed.

CONCLUSIONS

All endoscopic resection methods, including EMR-P, ESD-S, and ESD, were effective and safe for the treatment of colorectal neoplasms. Technically demanding ESD with high en bloc and complete resection rate should be reserved for the suspicious cancer lesion, which requires the precise histological evaluation. EMR-P with good feasibility can be considered an alternative to ESD for the lesions less than 20 mm.

Premalignant conditions of gastric cancer

Premalignant lesions of gastric cancer encompass a variety of conditions such as chronic gastritis, intestinal metaplasia and dysplasia, in which elevated risk of developing gastric cancer have been documented. Among them, intestinal metaplasia is frequently encountered in our daily endoscopic examination, yet its clinical significance is often underestimated despite of a number of reports demonstrating genetic and epigenetic alterations in the intestinal metaplastic mucosa. In this review, I will describe the molecular mechanisms of phenotypic changes from gastric mucosa to intestinal metaplasia based on our analysis of mouse model of intestinal metaplasia generated by ectopic expression of CDX2 in conjunction with the studies with human intestinal metaplasia.

Highlights of the 48th seminar of korean society of gastrointestinal endoscopy

This special May issue of Clinical Endoscopy discusses the tutorial contents dealing with either the diagnostic or therapeutic gastrointestinal (GI) endoscopy that contain very fundamental and essential points in this filed. The seminar of Korean Society of Gastrointestinal Endoscopy (KSGE) had positioned as one of prime educational seminars covering the very beginner to advanced experts of GI endoscopy. Besides of four rooms allocated for each lecture, two additional rooms were open for either live demonstration or hands-on course, covering totally 20 sessions including one special lecture. Among these prestigious lectures, 12 lectures were selected for the current review articles in this special issue of Clinical Endoscopy journal. Basic course for beginner to advanced tips to expert were all covered in this seminar. This introductory review prepared by four associated editors of Clinical Endoscopy contained core contents divided into four sessions-upper gut, lower gut, pancreaticobiliary, and specialized topic session part-to enhance understandings not covered by enlisted review articles in this issue.

Evaluation of the reliability of clinical staging of T2 N0 esophageal cancer: a review of the Society of Thoracic Surgeons database

BACKGROUND

Clinical staging of esophageal cancer has improved with positron-emission tomography/computed tomography and endoscopic ultrasound imaging. Despite such progress, small single-center studies have questioned the reliability of clinical staging of T2 N0 esophageal cancer. This study broadly examines the adequacy of clinical staging of T2 N0 disease using The Society of Thoracic Surgeons database.

METHODS

We retrospectively studied 810 clinical stage T2 N0 patients from 2002 to 2011, with 58 excluded because of incomplete pathologic staging data. Clinical stage, pathologic stage, and preoperative characteristics were recorded. Logistic regression analysis was used to identify factors associated with upstaging at the time of surgical intervention.

RESULTS

Among 752 clinical stage T2 N0 patients, 270 (35.9%) received induction therapy before the operation. Of 482 patients who went directly to surgical intervention, 132 (27.4%) were confirmed as pathologic T2 N0, 125 (25.9%) were downstaged (ie, T0-1 N0), and 225 (46.7%) were upstaged at the operation (T3-4 N0 or Tany N1-3). Exclusive tumor upstaging (ie, pathologic T3-4 N0) accounted for 41 patients (18.2%), whereas exclusive nodal upstaging (ie, pathological T1-2 N1-3) accounted for 100 (44.5%). Combined tumor and nodal upstaging (ie, pathological T3-4 N1-3) accounted for 84 patients (37.3%). Among patients who received induction therapy, 103 (38.1%) were upstaged vs 225 (46.7%) without induction therapy (p = 0.026). Comparing the induction therapy group and the primary surgical group, postoperative 30-day mortality (3.7% vs 3.7%, p > 0.99) and morbidity (46.3% vs 45%, p = 0.76) were similar.

CONCLUSIONS

Despite advances in staging techniques, clinical staging of T2 N0 esophageal cancer remains unreliable. Recognizing T2 N0 as a threshold for induction therapy in esophageal cancer, many surgeons have opted to treat T2 N0 disease with induction therapy, even though one-quarter of these patients will be pathologic T1 N0. Although this study demonstrated similar perioperative morbidity and mortality with and without induction therapy, further study is needed to examine the effect of upstaging on long-term survival.

Gastric carcinoma: imaging diagnosis, staging and assessment of treatment response

Gastric carcinoma (GC) is one of the most common causes of cancer-related death worldwide. Surgical resection is the only cure available and is dependent on the GC stage at presentation, which incorporates depth of tumor invasion, extent of lymph node and distant metastases. Accurate preoperative staging is therefore essential for optimal surgical management with consideration of preoperative and/or postoperative chemotherapy. Multidetector computed tomography (MDCT) with its ability to assess tumor depth, nodal disease and metastases is the preferred technique for staging GC. Endoscopic ultrasonography is more accurate for assessing the depth of wall invasion in early cancer, but is limited in the assessment of advanced local or stenotic cancer and detection of distant metastases. Magnetic resonance imaging (MRI), although useful for staging, is not proven to be effective. Positron emission tomography (PET) is most useful for detecting and characterizing distant metastases. Both MDCT and PET are useful for assessment of treatment response following preoperative chemotherapy and for detection of recurrence after surgical resection. This review article discusses the usefulness of imaging modalities for detecting, staging and assessing treatment response for GC and the potential role of newer applications including CT volumetry, virtual gastroscopy and perfusion CT in the management of GC.

Recurrence of non-invasive intraductal papillary municious neoplasm seven years following total pancreatectomy

INTRODUCTION

Intraductal papillary mucinous neoplasm is an increasingly recognized disease with varying premalignant potential and unclear incidence, characterized by a mucin-producing epithelium and dilation of the pancreatic duct.

PRESENTATION OF CASE

We present the first documented case of distant intestinal intraductal papillary mucinous neoplasm recurrence following total pancreatectomy for side-branch non-invasive borderline malignant intraductal papillary mucinous neoplasm.

DISCUSSION

We review the current literature in order to try and answer important questions regarding our ability to predict intraductal papillary mucinous neoplasm recurrence, our understanding of the potential for recurrence and what follow-up should be recommended to properly monitor recurrence after a benign, albeit borderline malignant, side-branch lesion resection.

CONCLUSION

Our case report confirms that the low risk classification of an intraductal papillary mucinous neoplasm lesion even after total pancreatectomy does not always predict recurrence and that definitive prognostic factors of recurrence in the setting of non-invasive disease have yet to be identified. A vigilant long-term approach to follow-up may thus be required even in low risk cases.

[Pain in connection with colonoscopy in Norway]

BACKGROUND

Colonoscopies are common examinations at Norwegian hospitals. In contrast to many other countries, the majority of colonoscopies in Norway are conducted without routine sedation or analgesia. We wanted to investigate whether current Norwegian practice offers adequate pain relief.

MATERIAL AND METHOD

The material consists of prospectively recorded outpatient colonoscopies in the period January 2003-December 2011 performed at Norwegian hospitals in the quality assurance network for gastrointestinal endoscopy (Gastronet). We analysed demographic patient data and data from colonoscopies. Patients' experience of pain (none, slight, moderate or severe pain) in connection with the examination was established with the aid of a validated questionnaire.

RESULTS

Data from 61,749 colonoscopies (55% on women) performed at 29 different hospitals were analysed. Colonoscopies were perceived as moderately or very painful by 33% of the patients (41% of the women, 24% of the men, p < 0.001). There were substantial differences between hospitals as to the percentage of colonoscopies that were perceived as moderately or very painful (from 9% to 43%, p < 0.001) and the use of sedatives and analgesics for the colonoscopies (from 1% to 92% of the examinations, p < 0.001). Only 23% of those who found the colonoscopy painful received analgesics. Pethidine was used in 95% of the cases in which analgesics were used during the examination.

INTERPRETATION

Many patients find colonoscopies painful. Pain relief practice varies substantially between hospitals. Pethidine is an analgesic with a slow onset of action, and should perhaps be replaced with more rapidly acting opiates.

Constitutive formulations for the mechanical investigation of colonic tissues

A constitutive framework is provided for the characterization of the mechanical behavior of colonic tissues, as a fundamental tool for the development of numerical models of the colonic structures. The constitutive analysis is performed by a multidisciplinary approach that requires the cooperation between experimental and computational competences. The preliminary investigation pertains to the review of the tissues histology. The complex structural configuration of the tissues and the specific distributions of fibrous elements entail the nonlinear mechanical behavior and the anisotropic response. The identification of the mechanical properties requires to perform mechanical tests according to different loading situations, as different loading directions. Because of the typical functionality of colon structures, the tissues mechanics is investigated by tensile tests, which are performed on taenia coli and haustra specimens from fresh pig colons. Accounting for the histological investigation and the results from the mechanical tests, a specific hyperelastic framework is provided within the theory of fiber-reinforced composite materials. Preliminary analytical formulations are defined to identify the constitutive parameters by the inverse analysis of the experimental tests. Finite element models of the specimens are developed accounting for the actual configuration of the colon structures to verify the quality of the results. The good agreement between experimental and numerical model results suggests the reliability of the constitutive formulations and parameters. Finally, the developed constitutive analysis makes it possible to identify the mechanical behavior and properties of the different colonic tissues.

Arterial bleeding during EUS-guided pseudocyst drainage stopped by placement of a covered self-expandable metal stent

BACKGROUND

Hemorrhagic complications during EUS-guided pseudocyst drainage can occur, because the vessels on the internal wall of the pseudocyst might be compressed by the fluid and thus not visible on color Doppler or even power Doppler EUS.

CASE PRESENTATION

We report a case of an immediate internal spurting arterial bleeding precipitated during EUS-guided pseudocyst drainage which stopped instantaneously by placement of a double flanged covered self-expandable metal stent through mechanical hemostasis.

CONCLUSION

In an unusual situation of bleeding from collateral circulation near the pseudocyst wall during pseudocyst drainage, the placement of an expandable metal stent proved to be useful.

Is idiopathic recurrent pancreatitis attributed to small stones?

Idiopathic recurrent pancreatitis remains a clinical challenge. Intraductal ultrasonography in the management of idiopathic recurrent pancreatitis may be a new strategy for undetermined causes after initial diagnostic approaches, including endoscopic retrograde cholangio-pancreatography (ERCP). However, no definite cause after ERCP should be defined under optimal settings and with experienced technique.

Comparison of magnetic resonance enterography, capsule endoscopy and gastrointestinal radiography of children with small bowel Crohn's disease

The aim of this study was to compare magnetic resonance enterography (MRE) findings with those of video capsule endoscopy (VCE) or conventional gastrointestinal radiography (CGR) in pediatric patients with small bowel Crohn's disease. A total of 55 cases of small bowel Crohn's disease that were diagnosed through clinical, laboratory, surgical and histopathological findings were reviewed. Prior to the examination, children suspected of having other types of diseases of the small intestinal were identified. The pulse sequences included coronal T2-true-fast imaging with steady-state precession (TrueFISP) images, navigation axial and coronal T1-weighted images, T2-weighted fat-suppressed images and coronal fat-suppressed three-dimensional gradient-echo images, immediately followed by contrast-enhanced axial and coronal T1-weighted fat-suppressed images. Findings from MRE were compared with those of VCE (n=39) and CGR (n=37). MRE results exhibited a number of features characteristic to small bowel Crohn's disease, including wall thickening, mesenteric fibrofatty changes and mesenteric vasculature changes. VCE, MRE and CGR demonstrated sensitivities of 94.6, 85.7 and 71.1% with specificities of 72.7, 70 and 40%; accuracies of 89.6, 82.2 and 61.1%; positive predictive values of 92.1, 90.9 and 59.6%; and negative predictive values of 80, 58.3 and 40%, respectively. VCE depicted mucosal pathologies missed by MRE in three patients. MRE revealed 83 extraenteric findings in 55 patients and CGR was able to show the dynamic evolution of the gastrointestinal function. MRE is a simple, safe, non-invasive and effective method for evaluating small bowel Crohn's disease. VCE allows visualization and readily characterizes subtle mucosal lesions missed by MRE, whereas MRE yields additional mural, perienteric and extraenteric information. However, oral barium CGR utilizes radiation, which is not suitable for repeated use in children.

EUS-Guided Vascular Procedures: A Literature Review

Endoscopic ultrasound (EUS) is continuously stepping into the therapeutic arena, simultaneously evolving in different directions, such as the management of pancreatic and biliary diseases, celiac neurolysis, delivering local intratumoral therapy, and EUS-guided endosurgery. EUS-guided vascular procedures are also challenging, considering the variety of vascular pathology, proximity of the vascular structures to the GI tract wall, high resolution, and real-time guidance offering an attractive access route and precise delivery of the intervention. The literature on vascular therapeutic EUS demonstrates techniques for the management of upper GI variceal and nonvariceal bleeding, pseudoaneurysms, and coiling and embolization procedures, as well as the creation of intrahepatic portosystemic shunts. The paucity of studies, diversity of study designs, and the number of animal model studies hamper a systematic approach to the conclusion and decision making important to clinicians and healthcare policy makers. Nevertheless, theoretical benefits and findings up to date concerning technical feasibility, efficacy, and safety of the procedures drive further research and development in this rather young therapeutic arena.

Metal stents: a bridge to surgery in hilar cholangiocarcinoma

BACKGROUND

Obstructive jaundice in patients with hilar cholangiocarcinoma is a known risk factor for hepatic failure after liver resection. Plastic stents are most widely used for preoperative drainage. However, plastic stents are known to have limited patency time and therefore, in palliative settings, the self-expanding metal stent (SEMS) is used. This type of stent has been shown to be superior because it allows for rapid biliary decompression and a reduced complication rate after insertion. This study explores the use of the SEMS for biliary decompression in patients with operable hilar cholangiocarcinoma.

METHODS

A retrospective evaluation of a prospectively maintained database at a tertiary hepatobiliary referral centre was carried out. All patients with resectable cholangiocarcinoma were recorded.

RESULTS

Of 260 patients referred to this unit with cholangiocarcinoma between January 2008 and April 2012, 50 patients presented with operable cholangiocarcinoma and 27 of these had obstructive jaundice requiring stenting. Ten patients were initially treated with SEMSs; no stent failure occurred in these patients. Seventeen patients initially received plastic stents, seven of which failed in the interval between stent placement and laparotomy. These stents were replaced by SEMSs in four patients and by plastic stents in three patients. Median time to laparotomy was 45 days and 68 days in patients with SEMSs and plastic stents, respectively.

CONCLUSIONS

Self-expanding metal stents provide adequate and rapid biliary drainage in patients with obstruction caused by hilar cholangiocarcinoma. No re-interventions were required. This probably reflects the relatively short interval between stent placement and laparotomy.

Routine use of simultaneous laparoendoscopic approach in patients with confirmed gallbladder and bile duct stones: fit for laparoscopy fit for "rendezvous"

BACKGROUND

The aim of the present work was to determine the feasibility and efficacy, in terms of equipment coordination and timing, of the laparoendoscopic intraoperative rendezvous technique (RVT) for the treatment of gallbladder and common bile duct stones (CBDS).

METHODS

The procedure was considered in 269 unselected patients with a suspicion or preoperative imaging demonstration of CBDS who were fit for laparoscopic cholecystectomy (LC). Common bile duct stones were confirmed by intraoperative laparoscopic cholangiography (IOC) in only 113 of these patients (42 %). In 17 (15 %) patients the planned procedure was aborted because of organizational problems, mainly the unavailability of endoscopists in the urgent setting. The remaining 96 patients (84 %) underwent a formal attempt at RVT. Intraoperative endoscopic retrograde cholangiography (ERC) was performed, during LC, by means of a guidewire that reached the duodenum through the cystic duct.

RESULTS

In 18 patients (19 %) the complete procedure failed, either because of difficulty in passing the guidewire through the papilla or because of other technical difficulties that required conversion to laparotomy. An intraoperative ERC was completed in six patients in the classical way (no guidewire) without conversion. No mortality and few complications were recorded (3 % overall: 1 perforation and 2 cholangitis). Retained stones were successively detected in 6 patients (6 %) and successfully retreated by a further ERC. Globally, the one-stage procedure (with and without the guidewire) was possible in 84 of 96 patients (87 %).

CONCLUSIONS

The RVT appears to be effective and safe as it was performed at our institution, with an overall percentage of definitive success (passed guide wire and no further ERC) of 81 %. The RVT should be considered as a good option for the treatment of simultaneous gallstones and CBDS.

Interobserver agreement for confocal imaging of ampullary lesions: a multicenter single-blinded study

BACKGROUND

Malignant ampullary lesions can be difficult to classify by endoscopy alone. Probe-based confocal laser endomicroscopy (pCLE) permits in vivo assessment of mucosal structures in the gastrointestinal tracts in the real time.

AIM

The objective of this pilot multicenter study was to assess the interobserver agreement and variance in interpretation of pCLE of ampullary lesions.

METHODS

Twelve pCLE video clips of ampullary lesions were distributed to 6 gastrointestinal specialists at 5 medical centers, blinded to final pathologic results. Six variables were assessed for interobserver agreement using κ statistics. Variables included an epithelial outer border with irregular thickness, dark epithelium without discernable individual cells, heterogenously distributed elongated crypts, reduced number of goblet cells, neovascularization, and final diagnosis.

RESULTS

The overall interobserver agreement for all observers was poor to slight for all variables (κ=0.02, 0.05, -0.01, 0.04, 0.018) except for the first variable with fair degree of agreement (κ=0.27). On the basis of experience, 3 observers were classified as less experienced, whereas 3 were classified as most experienced. Upon stratification, the less experienced observers had poor interobserver agreement for all variables, except 1. The most experienced observers had poor agreement for 2 variables, slight agreement for 3 variables, and fair agreement for the final diagnosis variable.

CONCLUSIONS

The overall interpersonal agreement on pCLE for ampullary lesions was poor. The interobserver agreement was not substantially improved for experienced raters. Further standardization of pCLE image criteria is needed for ampullary lesions. Standardized training may improve interrater reliability to an acceptable level.

Refractory strictures post-esophageal atresia repair: what are the alternatives?

Esophageal strictures remain the most frequent complication after esophageal atresia (EA) repair despite refinements in operative techniques. With an incidence of anastomotic stricture between 8% and 49%, EA is the most frequent cause of benign esophageal stricture in children. The mainstay of treatment for esophageal stricture is dilatation with a 58-96% success rate. In order to relieve dysphagia, between 1 and 15 dilatations will be required in each EA patient with an esophageal stricture. However dilatations may lead to complications including perforation (0.1-0.4% of all esophageal benign strictures) and sociopsychological morbidity. Fifty percent of EA strictures will improve in 6 months. However, 30% will persist and require repeat dilatations. The present article explores the variety of non-surgical alternative treatments for anastomotic strictures after EA repair, focusing on triamcinolone acetonide, mitomycin C and esophageal stents. We propose an algorithm for a more standardized therapeutic approach, with the hope that an international panel of experts could meet and establish a consensus.

Small bowel video capsule endoscopy: an overview

Video capsule endoscopy (VCE) is being increasingly used to investigate small bowel pathology. It is the gold standard for obscure gastrointestinal bleeding and iron deficiency anemia. VCE has been in use since 2001 and indications for its use are expanding. VCE is also a useful diagnostic tool in small bowel Crohn's disease, celiac disease, surveillance of polyps, small bowel malignancy and drug-induced small bowel injury. Although VCE is considered a safe and easy procedure, there are a few limitations. These include cost, capsule retention and inability to take a biopsy and perform any therapeutic maneuvers. Contraindications for VCE include pregnancy, patients with a swallowing disorder, history of previous abdominal surgery or concurrent abdomino-pelvic irradiation. This is an overview of VCE, its role and indications in clinical practice, potential complications and contraindications, as well as the ongoing and expected advances in the field.

Wireless insufflation of the gastrointestinal tract

Despite clear patient experience advantages, low specificity rates have thus far prevented swallowable capsule endoscopes from replacing traditional endoscopy for diagnosis of colon disease. One explanation for this is that capsule endoscopes lack the ability to provide insufflation, which traditional endoscopes use to distend the intestine for a clear view of the internal wall. To provide a means of insufflation from a wireless capsule platform, in this paper we use biocompatible effervescent chemical reactions to convert liquids and powders carried onboard a capsule into gas. We experimentally evaluate the quantity of gas needed to enhance capsule visualization and locomotion, and determine how much gas can be generated from a given volume of reactants. These experiments motivate the design of a wireless insufflation capsule, which is evaluated in ex vivo experiments. These experiments illustrate the feasibility of enhancing visualization and locomotion of endoscopic capsules through wireless insufflation.

Narrow-band imaging with dual focus magnification in differentiating colorectal neoplasia

BACKGROUND

Real-time optical diagnosis of colorectal polyps may lead to substantial time and cost savings and could potentially reduce complications associated with polypectomy. We prospectively assessed the utility of a novel narrow-band imaging (NBI) system with dual focus magnification (DF) in differentiating colorectal polyps in consecutive patients undergoing colonoscopy.

PATIENTS AND METHODS

All procedures were carried out with a prototype 190 series Exera III NBI system with Dual Focus capability. Histology of each polyp was predicted in real time with NBI-DF based on the modified Sano's classification with a confidence level (low/high). NBI-DF diagnosis was then compared to the final (blinded) histopathology results. Primary endpoint was the accuracy of endoscopic prediction with the modified Sano's classification of all polyps when they were diagnosed with high confidence. Secondary endpoints were the accuracy of post-polypectomy surveillance intervals for diminutive polyps(≤ 5 mm). A total of 164 polyps in 87 patients (53 males) with a mean age of 63 (range 28-86) years were evaluated.

RESULTS

149 polyps were diagnosed with high confidence on endoscopic prediction, out of which 80 were diminutive, 31 small (6-9 mm) and 38 large (>10 mm). Overall accuracy of NBI-DF compared to final histopathology was 97%. The accuracy for post-polypectomy surveillance interval based on the endoscopic prediction was 97%. The NPV for diminutive rectosigmoid polyps for adenomatous histology was 100%.

CONCLUSION

In this preliminary feasibility study, NBI-DF permitted prediction of histology of colorectal polyps with high accuracy. In addition, both of the secondary endpoints exceeded the ASGE PIVI thresholds for the management of diminutive polyps.

Comparison of gastrotomy closure modalities for natural orifice transluminal surgery: a canine study

BACKGROUND

Reliable closure of the gastrotomy after transgastric natural orifice transluminal endoscopic surgery (NOTES) remains unresolved.

OBJECTIVE

To compare the technical aspects and clinical and histologic outcomes of NOTES gastrotomy closure techniques.

DESIGN

Experimental study.

SETTING

Animal laboratory.

PATIENTS

Thirty-four dogs, 14 for nonsurvival study and 20 for survival study.

INTERVENTIONS

The animals randomly received different gastrotomy closures after NOTES: endoclip, omentoplasty, over-the-scope-clip (OTSC), and hand-suturing.

MAIN OUTCOME MEASUREMENTS

Procedure time, closure strength, survival, postoperative adverse events, and histologic evaluation of wound healing.

RESULTS

Omentoplasty and OTSC groups needed shorter procedure times and fewer clips than the endoclip group. The endoclip and omentoplasty groups generated similar leakage pressures (34.5 ± 2.6 vs 42.2 ± 4.1 mm Hg, P > .05), both lower than OTSC and hand-suturing groups (81.5 ± 2.1 and 87.0 ± 3.0 mm Hg, respectively, P < .001). Of the 20 animals in the survival study (all 4 groups), only 2 of 6 in the endoclip group were killed prematurely due to sepsis. Necropsy revealed the OTSC group reached a 100% clip retention rate, higher than the endoclip (47.9%) and omentoplasty groups (44.4%, P < .05) rates. Complete healing, defined as intact and continuous gastric layers microscopically, was seen in 83.3% of animals (5 of 6) in the omentoplasty group, comparable with OTSC (4 of 6, 66.7%, P = .500) but higher than the endoclip group (1 of 6, 16.7%, P = .04).

LIMITATIONS

Animal study.

CONCLUSIONS

Omentoplasty is easier and safer for NOTES gastrotomy closure than endoclips and offers safety profile and efficacy similar to OTSC and hand-suturing.

Water intubation method can reduce patients' pain and sedation rate in colonoscopy: a meta-analysis

Several randomized controlled trials (RCT) have shown that water infusion in lieu of air insufflation reduces sedation rate and pain score and increases cecal intubation rate in colonoscopy. The aim of the present study was to confirm the beneficial effects of the water intubation method over the air method. Electronic databases were searched to identify RCT reporting colonoscopy detection using the water method. The pooled data of sedation rate, pain score and other procedure-related outcomes were analyzed. Then, 15 full-text articles were selected and assessed. Nine trials with high-quality scores were enrolled into this meta-analysis including a total of 1414 participants. Pooled odds ratio (OR) of sedation rate was 0.392 (95% confidence interval (CI): 0.288-0.533, P = 0.000). Pooled weighted mean difference (WMD) of pain score was -1.543 (95% CI: -2.107--1.069,P = 0.000). Pooled OR of cecal intubation rate was 1.90 (95% CI: 1.29-2.82, P = 0.001). Pooled OR of polyp detection rate and adenoma detection rate were 0.805 (95% CI: 0.606-1.069, P = 0.134) and 0.913 (95% CI: 0.681-1.223, P = 0.168), respectively. Pooled WMD of cecal intubation time was 0.701 (95% CI: -0.486-1.889, P = 0.247). This meta-analysis confirmed that the water method significantly reduced sedation rate and degree of pain without decreasing cecal intubation rate and disease detection rate and without requiring more cecal intubation time, suggesting that the novel water method is better than the conventional air method in colonoscopy detection.

Duodenal somatostatinoma: a case report and review of the literature

Introduction

About 70% of well-differentiated endocrine tumors arise from the gastrointestinal tract. Duodenal well-differentiated endocrine tumors account for only 2.6% of all neuroendocrine tumors. Following the first two case reports of somatostatin-secreting tumors in 1977, fewer than 200 cases of somatostatinoma have been reported. These tumors of the duodenum are usually silent and asymptomatic, but can cause gastrointestinal symptoms. Depending on the localization of the tumor, multiple surgical procedures can be performed, ranging from local resection to pancreaticoduodenectomy.

Case presentation

Here, we report a case of a submucosal duodenal mass in a 42-year-old Turkish White man presenting with nausea, vomiting, fatigue and abdominal pain. The treatment decision of pancreaticoduodenectomy made preoperatively was later altered to intraoperative removal via local resection with sphincteroplasty.

Conclusion

Tumors of the periampullary region are considered highly malignant, and the Whipple operation is usually the only procedural treatment. In the current case, we decided not to perform pancreaticoduodenectomy but to excise the mass intraoperatively, and consequently avoided unnecessary resection of the pancreas and anastomosis to undilated hepatic and pancreatic ducts. This protective strategy prevented duodenum- and pancreas-related morbidity.

Different healing process of esophageal large mucosal defects by endoscopic mucosal dissection between with and without steroid injection in an animal model

Background

Stricture formation is one of the major complications after endoscopic removal of large superficial squamous cell neoplasms of the esophagus, and local steroid injections have been adopted to prevent it. However, fundamental pathological alterations related to them have not been well analyzed so far. The aim of this study was to analyze the time course of the healing process of esophageal large mucosal defects resulting in stricture formation and its modification by local steroid injection, using an animal model.

Methods

Esophageal circumferential mucosal defects were created by endoscopic mucosal dissection (ESD) for four pigs. One pig was sacrificed five minutes after the ESD, and other two pigs were followed-up on endoscopy and sacrificed at the time of one week and three weeks after the ESD, respectively. The remaining one pig was followed-up on endoscopy with five times of local steroid injection and sacrificed at the time of eight weeks after the ESD. The esophageal tissues of all pigs were subjected to pathological analyses.

Results

For the pigs without steroid injection, the esophageal stricture was completed around three weeks after the ESD on both endoscopy and esophagography. Histopathological examination of the esophageal tissues revealed that spindle-shaped α-smooth muscle actin (SMA)-positive myofibroblasts arranged in a parallel fashion and extending horizontally were identified at the ulcer bed one week after the ESD, and increased contributing to formation of the stenotic luminal ridge covered with the regenerated epithelium three weeks after the ESD. The proper muscle layer of the stricture site was thinned with some myocytes which seemingly showed transition to the myofibroblast layer. By contrast, for the pig with steroid injection, esophageal stricture formation was not evident with limited appearance of the spindle-shaped myofibroblasts, instead, appearance of stellate or polygocal SMA-positive stromal cells arranged haphazardly in the persistent granulation tissue of the ulcer site.

Conclusions

Proliferation of spindle-shaped myofibroblasts arranged in a parallel fashion is likely to play an important role in stricture formation after circumferential mucosal defects by esophageal ESD, which may be related to the thinning of the proper muscle layer in the healing course of the defects. Local steroid injection seems to be effective to prevent the stricture through the modification of this process.

Robotic control of a traditional flexible endoscope for therapy

In therapeutic flexible endoscopy a team of physician and assistant(s) is required to control all independent translations and rotations of the flexible endoscope and its instruments. As a consequence the physician lacks valuable force feedback information on tissue interaction, communication errors easily occur, and procedures are not cost-effective. Current tools are not suitable for performing therapeutic procedures in an intuitive and user-friendly way by one person. A shift from more invasive surgical procedures that require external incisions to endoluminal procedures that use the natural body openings could be expected if enabling techniques were available. This paper describes the design and evaluation of a robotic system which interacts with traditional flexible endoscopes to perform therapeutic procedures that require advanced maneuverability. The physician uses one multi-degree-of-freedom input device to control camera steering as well as shaft manipulation of the motorized flexible endoscope, while the other hand is able to manipulate instruments. We identified critical use aspects that need to be addressed in the robotic setup. A proof-of-principle setup was built and evaluated to judge the usability of our system. Results show that robotic endoscope control increases efficiency and satisfaction. Participants valued its intuitiveness, its accuracy, the feeling of being in control, and its single-person setup. Future work will concentrate on the design of a system that is fully functional and takes safety, cleanability, and easy positioning close to the patient into account.

Evaluation of the WHO 2010 grading and AJCC/UICC staging systems in prognostic behavior of intestinal neuroendocrine tumors

Background

The increasing incidence and heterogeneous behavior of intestinal neuroendocrine tumors (iNETs) pose a clinicopathological challenge. Our goal was to decribe the prognostic value of the new WHO 2010 grading and the AJCC/UICC TNM staging systems for iNETs. Moreover, outcomes of patients treated with somatostatin analogs were assessed.

Methods

We collected epidemiological and clinicopathological data from 93 patients with histologically proven iNETs including progression and survival outcomes. The WHO 2010 grading and the AJCC/UICC TNM staging systems were applied for all cases. RECIST criteria were used to define progression. Kaplan-Meier analyses for progression free survival (PFS) and overall survival (OS) were performed.

Results

Mean follow-up was 58.6 months (4–213 months). WHO 2010 grading yielded PFS and disease-specific OS of 125.0 and 165.8 months for grade 1 (G1), 100.0 and 144.2 months for G2 and 15.0 and 15.8 months for G3 tumors (p = 0.004 and p = 0.001). Using AJCC staging, patients with stage I and II tumors had no progression and no deaths. Stage III and IV patients demonstrated PFS of 138.4 and 84.7 months (p = 0.003) and disease-specific OS of 210.0 and 112.8 months (p = 0.017). AJCC staging also provided informative PFS (91.2 vs. 50.0 months, p = 0.004) and OS (112.3 vs. 80.0 months, p = 0.005) measures with somatostatin analog use in stage IV patients.

Conclusion

Our findings underscore the complementarity of WHO 2010 and AJCC classifications in providing better estimates of iNETS disease outcomes and extend the evidence for somatostatin analog benefit in patients with metastatic disease.

Mucosal-incision assisted biopsy for suspected gastric gastrointestinal stromal tumors

To evaluate the diagnostic yield of the procedure, mucosal-incision assisted biopsy (MIAB), for the histological diagnosis of gastric gastrointestinal stromal tumor (GIST), we performed a retrospective review of the 27 patients with suspected gastric GIST who underwent MIAB in our hospitals. Tissue samples obtained by MIAB were sufficient to make a histological diagnosis (diagnostic MIAB) in 23 out of the 27 patients, where the lesions had intraluminal growth patterns. Alternatively, the samples were insufficient (non-diagnostic MIAB) in remaining 4 patients, three of whom had gastric submucosal tumor with extraluminal growth patterns. Although endoscopic ultrasound and fine needle aspiration is the gold standard for obtaining tissue specimens for histological and cytological analysis of suspected gastric GISTs, MIAB can be used as an alternative method for obtaining biopsy specimens of lesions with an intraluminal growth pattern.

Interference between pacemakers/implantable cardioverter defibrillators and video capsule endoscopy

Our Letter to the Editor, related to the article “Small bowel capsule endoscopy in patients with cardiac pacemakers and implantable cardioverter defibrillators: Outcome analysis using telemetry” by Cuschieri et al, comments on some small errors, that slipped into the authors discussions. The given informations concerning the pacemaker- and implantable cardioverter defibrillators modes were inaccurate and differ between the text and the table. Moreover, as 8 of 20 patient’s pacemakers were programmed to VOO or DOO (“interference mode”) and one patient was not monitored by telemetry during capsule endoscopy, 9 of 20 patients (45%) lack the informations of possible interference between capsule endoscopy their implanted device. Another objection refers to the interpretation of an electrocardiogram (figure 1, trace B) presented: in contrast to the author’s opinion the marked spike should be interpreted as an artefact and not as ”undersensing of a fibrillatory wave”. Finally, three comments to cited reviews were not complete respectively not quoted correctly.

Tumors and new endoscopic ultrasound-guided therapies

With the advent of linear echoendoscopes, endoscopic ultrasound (EUS) has become more operative and a new field of oncological application has been opened up. From tumor staging to tissue acquisition under EUS-guided fine-needle aspiration, new operative procedures have been developed on the principle of the EUS-guided puncture. A hybrid probe combining radiofrequency with cryotechnology is now available, to be passed through the operative channel of the echoendoscope into the tumor to create an area of ablation. EUS-guided fine-needle injection is emerging as a method to deliver anti-tumoral agents inside the tumor. Ethanol lavage, with or without paclitaxel, has been proposed for the treatment of cystic tumors in non-resectable cases and complete resolution has been recorded in up to 70%-80%. Many other chemical or biological agents have been investigated for the treatment of pancreatic adenocarcinoma: activated allogenic lymphocyte culture (Cytoimplant), a replication-deficient adenovirus vector carrying the tumor necrosis factor-α gene, or an oncolytic attenuated adenovirus (ONYX-015). The potential advantage of treatment under EUS control is the real-time imaging guidance into a deep target like the pancreas which is extremely difficult to reach by a percutaneous approach. To date there are no randomized controlled trials to confirm the real clinical benefits of these treatments compared to standard therapy so it seems wise to reserve them only for experimental protocols approved by ethics committees.

Endocytoscopic visualization of squamous cell islands within Barrett's epithelium

AIM

To study the endocytoscopic visualization of squamous cell islands within Barrett's epithelium.

METHODS

Endocytoscopy (ECS) has been studied in the surveillance of Barrett's esophagus, with controversial results. In initial studies, however, a soft catheter type endocytoscope was used, while only methylene blue dye was used for the staining of Barrett's mucosa. Integrated type endocytoscopes (GIF-Q260 EC, Olympus Corp, Tokyo, Japan) have been recently developed, with the incorporation of a high-power magnifying endocytoscope into a standard endoscope together with narrow-band imaging (NBI). Moreover, double staining with a mixture of 0.05% crystal violet and 0.1% of methylene blue (CM) during ECS enables higher quality images comparable to conventional hematoxylin eosin histopathological images.

RESULTS

In vivo endocytoscopic visualization of papillary squamous cell islands within glandular Barrett's epithelium in a patient with long-segment Barrett's esophagus is reported. Conventional white light endoscopy showed typical long-segment Barrett's esophagus, with small squamous cell islands within normal Barrett's mucosa, which were better visualized by NBI endoscopy. ECS after double CM staining showed regular Barrett's esophagus, while higher magnification (× 480) revealed the orifices of glandular structures better. Furthermore, typical squamous cell papillary protrusion, classified as endocytoscopic atypia classification (ECA) 2 according to ECA, was identified within regular glandular Barrett's mucosa. Histological examination of biopsies taken from the same area showed squamous epithelium within glandular Barrett's mucosa, corresponding well to endocytoscopic findings.

CONCLUSION

To our knowledge, this is the first report of in vivo visualization of esophageal papillary squamous cell islands surrounded by glandular Barrett's epithelium.

Endoscopic management of acute pancreatitis

Patients presenting with acute pancreatitis can be complex on different levels. Having a multifaceted approach to these patients is often necessary with radiographic, endoscopic, and surgical modalities all working to benefit the patient. Major surgical intervention can often be avoided or augmented by therapeutic and diagnostic endoscopic maneuvers. The diagnostic role of endoscopy in patients presenting with acute idiopathic pancreatitis can help define specific causative factors and ameliorate symptoms by endoscopic maneuvers. Etiologies of an acute pancreatitis episode, such as choledocholithiasis with or without concomitant cholangitis, microlithiasis or biliary sludge, and anatomic anomalies, such as pancreas divisum and pancreatobiliary ductal anomalies, often improve after endoscopic therapy.

Treatments for esophageal cancer: a review

Esophageal cancer is the eighth most common form of cancer worldwide. The treatments for esophageal cancer depend on its etiology. For mucosal cancer, endoscopic mucosal resection and endoscopic submucosal dissection are standard, while for locally advanced cancer, esophagectomy remains the mainstay. The three most common techniques for thoracic esophagectomy are the transhiatal approach, the Ivor Lewis esophagectomy (right thoracotomy and laparotomy), and the McKeown technique (right thoracotomy followed by laparotomy and neck incision with cervical anastomosis). Surgery for carcinoma of the cervical esophagus requires an extensive procedure with laryngectomy in many cases. When the tumor is more advanced, neoadjuvant chemotherapy or neoadjuvant chemoradiotherapy is added. The theoretical advantages of adding chemotherapy to the treatment of esophageal cancer are potential tumor down-staging prior to surgery, as well as targeting micrometastases and, thus, decreasing the risk of distant metastasis. Cisplatin- and 5-fluorouracil-based regimes are used worldwide. Chemoradiotherapy is the standard for unresectable esophageal cancer and could also be considered as an option for resectable tumors. For patients who are medically or technically inoperable, concurrent chemoradiotherapy should be the standard of care. Although neoadjuvant chemoradiotherapy followed by surgery or salvage surgery after definitive chemoradiotherapy is a practical treatment; judicious patient selection is crucial. It is important to have a thorough understanding of these therapeutic modalities to assist in this endeavor.

Transvaginal pure NOTES sigmoid resection using a single port device

BACKGROUND

The amount of published experience using natural orifice transluminal endoscopic surgery (NOTES) is increasing. However, approximately half of the technical approaches described include NOTES as part of a hybrid procedure. Colonic resections performed using NOTES have mainly been described using a hybrid approach.

METHODS

An 84-year-old female presented with a symptomatic volvulus of the sigmoid colon. Endoscopic detorsion and desufflation were successfully performed. Definitive treatment was accomplished by performing a sigmoid resection entirely via a transvaginal route using a single port device (SILS™ Covidien, Westbury, MA, USA).

RESULTS

Operative time was 135 min. No intraoperative or postoperative complications occurred. Only minimal narcotic analgesia was required and oral intake was initiated on postoperative day 3. At the last follow-up assessment, 2 months postoperatively, no complications or recurrent volvulus were observed.

CONCLUSION

Transvaginal NOTES sigmoid colectomy for sigmoid volvulus is feasible and can be performed safely.

Synchronous vs sequential laparoscopic cholecystectomy for cholecystocholedocholithiasis

AIM

To compare synchronous laparoscopic cholecystectomy (LC) combined with endoscopic sphincterotomy (EST) and sequential LC combined with EST for treating cholecystocholedocholithiasis.

METHODS

A total of 150 patients were included and retrospectively studied. Among these, 70 were selected for the synchronous operation, in which the scheme was endoscopic retrograde cholangiopancreatography combined with EST during LC. The other 80 patients were selected for the sequential operation, in which the scheme involved first cutting the papillary muscle under endoscopy and then performing LC. The indexes in the two groups, including the operation time, the success rate, the incidence of complications, and the length of the hospital stay, were observed.

RESULTS

There were no significant differences between the groups in terms of the numbers of patients, sex distribution, age, American Society of Anesthesiologists score, serum bilirubin, γ-glutamyl transpeptidase, mean diameter of common bile duct stones, and previous medical and surgical history (P = 0.54, P = 0.18, P = 0.52, P = 0.22, P = 0.32, P = 0.42, P = 0.68, P = 0.70, P = 0.47 and P = 0.57). There was no significant difference in the surgical operation time between the two groups (112.1 ± 30.8 min vs 104.9 ± 18.2 min). Compared with the sequential operation group, the incidence of pancreatitis was lower (1.4% vs 6.3%), the incidence of hyperamylasemia (1.4% vs 10.0%, P < 0.05) was significantly reduced, and the length of the hospital stay was significantly shortened in the synchronous operation group (3 d vs 4.5 d, P < 0.001).

CONCLUSION

For treatment of cholecystocholedocholithiasis, synchronous LC combined with EST reduces incidence of complications, decreases length of hospital stay, simplifies the surgical procedure, and reduces operation time.

Missed diagnosis of early gastric cancer or high-grade intraepithelial neoplasia

AIM: To investigate the causes of missed diagnosis of early gastric cancer (EGC) or high-grade intraepithelial neoplasia (HGIN) in Chongqing, China.

METHODS: The present study summarizes 103 cases of EGC/HGIN detected by esophagogastroduodenoscopy (EGD) and pathological analysis from January 2010 to December 2011. Dimethyl silicone oil was administrated orally 15 min before the EGD procedures. The stomach was cleaned by repeated washing with saline when the gastroscope entered the stomach cavity. Suspected EGC lesions were subject to conventional biopsy sampling and pathological examinations. The correlation between lesion locations, endoscopic morphology of cancerous sites, training level of the examiners, pathological biopsies, and missed diagnosis was analyzed.

RESULTS: Twenty-three cases were missed among the 103 cases (22.23%) of EGC/HGIN. The rate of missed EGC in the gastroesophageal junction (8/19, 42.1%) was significantly higher than at other sites (15/84, 17.86%) (χ² = 5.253, P = 0.022). In contrast, the rate of missed EGC in the lower stomach body (2/14, 14.29%) was lower than at other sites (21/89, 23.6%), but there were no significant differences (χ² = 0.289, P = 0.591). The rate of missed EGC in the gastric antrum (5/33, 15.15%) was lower than at other sites (18/70, 25.71%), but there were no significant differences (χ² = 1.443, P = 0.230). Endoscopists from less prestigious hospitals were more prone to not diagnosing EGC than those from more prestigious hospitals (χ² = 4.261, P = 0.039). When the number of biopsies was < 4, the rate of missed diagnosis was higher (20/23, 89.96%) than for when there were > 4 biopsies (3/23, 13.04%) (P < 0.001). In addition, there was no significant difference in the rate of missed diagnosis in patients with 1-3 biopsy specimens (χ² = 0.141, P = 0.932).

CONCLUSION: Endoscopists should have a clear understanding of the anatomical characteristics of the esophagus/stomach, and endoscopic identification of early lesions increases with the number of biopsies.

Asymptomatic isolated partial hiatal herniation of the pancreas: MDCT evaluation and anatomical explanation: case report and review of literature

Isolated herniation of the pancreas through a gastroesophageal hiatus is an extremely rare condition, and only one case has been reported in the world literature. We describe a MDCT diagnosis of isolated partial hiatal hernia containing the body of a normal pancreas in an asymptomatic patient, give an anatomical explanation and review the corresponding literature.

Capsule Endoscopy in Patients with Implantable Electromedical Devices is Safe

Background and Study Aims. The presence of an implantable electromechanical cardiac device (IED) has long been considered a relative contraindication to the performance of video capsule endoscopy (CE). The primary aim of this study was to evaluate the safety of CE in patients with IEDs. A secondary purpose was to determine whether IEDs have any impact on images captured by CE. Patients and Methods. A retrospective chart review of all patients who had a capsule endoscopy at Mayo Clinic in Scottsdale, AZ, USA, or Rochester, MN, USA, (January 2002 to June 2010) was performed to identify CE studies done on patients with IEDs. One hundred and eighteen capsule studies performed in 108 patients with IEDs were identified and reviewed for demographic data, method of preparation, and study data. Results. The most common indications for CE were obscure gastrointestinal bleeding (77%), anemia (14%), abdominal pain (5%), celiac disease (2%), diarrhea (1%), and Crohn's disease (1%). Postprocedure assessments did not reveal any detectable alteration on the function of the IED. One patient with an ICD had a 25-minute loss of capsule imaging due to recorder defect. Two patients with LVADs had interference with capsule image acquisition. Conclusions. CE did not interfere with IED function, including PM, ICD, and/or LVAD and thus appears safe. Additionally, PM and ICD do not appear to interfere with image acquisition but LVAD may interfere with capsule images and require that capsule leads be positioned as far away as possible from the IED to assure reliable image acquisition.

IMPROVEMENT OF SCHISTOSOMAL PORTAL HYPERTENSIVE COLOPATHY AFTER SURGICAL TREATMENT

Context Data on vascular alterations in patients with hepatosplenic schistosomiasis and portal hypertensive colopathy and changes in these after surgery to decrease portal hypertension are limited. Objective The purpose of this study was to analyse the alterations of portal hypertensive colopathy previously and 6-12 months after splenectomy and gastric devascularization. Methods Twelve patients with hepatosplenic schistosomiasis who also had upper gastrointestinal bleeding were studied prospectively. Their endoscopic findings before and 6-12 months after the surgery were analysed. In addition, mucosal biopsies from ascending colon, sigmoid colon and rectum at these time points were subjected to histological and histomorphometric assessment. It was used a control group due to lack of normal pattern of the histomorphometric measures of vessels in individuals without portal hypertension. The critical level of significance adopted in all tests was of a maximum probability error of 5%. Results Surgery did not lead to significant improvement in histological and endoscopic findings. However, on histomorphometry, there was a significant decrease in the area, diameter and thickness of the vessels in mucosa at all colonic sites. Conclusion Surgery for decompression of schistosomal portal hypertension has a beneficial effect on the associated colopathy, being best indicated in patients with gastrointestinal bleeding and esophageal varices.