Endoscopic mucosal tissue sampling

Immunotherapy of gastric cancer: Present status and future perspectives

In this editorial, we comment on the article entitled "Advances and key focus areas in gastric cancer immunotherapy: A comprehensive scientometric and clinical trial review (1999-2023)," which was published in the recent issue of the World Journal of Gastroenterology. We focused on the results of the authors' bibliometric analysis concerning gastric cancer immunotherapy, which they analyzed in depth by compiling the relevant publications of the last 20 years. Before that, we briefly describe the most recent data concerning the epidemiological parameters of gastric cancer (GC) in different countries, attempting to give an interpretation based on the etiological factors involved in the etiopathogenesis of the neoplasm. We then briefly discuss the conservative treatment (chemotherapy) of the various forms of this malignant neoplasm. We describe the treatment of resectable tumors, locally advanced neoplasms, and unresectable (advanced) cases. Special attention is given to modern therapeutic approaches with emphasis on immunotherapy, which seems to be the future of GC treatment, especially in combination with chemotherapy. There is also a thorough analysis of the results of the study under review in terms of the number of scientific publications, the countries in which the studies were conducted, the authors, and the scientific centers of origin, as well as the clinical studies in progress. Finally, an attempt is made to draw some con-clusions and to point out possible future directions.

Diagnosis and Pharmacological Management of Microscopic Colitis in Geriatric Care

Microscopic colitis, a diagnosis under the umbrella term of inflammatory bowel disease, is a prevalent cause of watery diarrhea, often with symptoms of urgency and bloating, typically observed in older adults aged ≥ 60 years. Its incidence has been reported to exceed those of ulcerative colitis and Crohn's disease in some geographical areas. Although nonpathognomonic endoscopic abnormalities, including changes of the vascular mucosal pattern; mucosal erythema; edema; nodularity; or mucosal defects, e.g., "cat scratches" have been reported, a colonoscopy is typically macroscopically normal. As reliable biomarkers are unavailable, colonoscopy using random biopsies from various parts of the colon is compulsory. Based on the histological examination under a microscope, the disease is divided into collagenous (with a thickened subepithelial collagenous band) and lymphocytic (with intraepithelial lymphocytosis) colitis, although incomplete forms exist. In routine clinical settings, the disease has a high risk of being misdiagnosed as irritable bowel syndrome or even overlooked. Therefore, healthcare providers should be familiar with clinical features and rational management strategies. A 6-8-week oral budesonide treatment course (9 mg/day) is considered the first-line therapy, but patients often experience relapse when discontinued, or might become intolerant, dependent, or even fail to respond. Consequently, other therapeutic options (e.g., bismuth subsalicylate, biologics, loperamide, bile acid sequestrants, and thiopurines) recommended by available guidelines may be prescribed. Herein, clinically meaningful data is provided based on the latest evidence that may aid in reaching a diagnosis and establishing rational therapy in geriatric care to control symptoms and enhance the quality of life for those affected.

Risk factors associated with recurrence of gastric hyperplastic polyps: a single-center, long-term, retrospective cohort study

BACKGROUND

The likelihood of recurrence of gastric hyperplastic polyps (GHPs) following endoscopic resection and the need for long-term follow-up remain unknown. We, therefore, aimed to investigate the factors associated with the recurrence and cumulative incidence of GHPs over a 10-year period.

METHODS

Between May 1995 and December 2020, 1,018 GHPs > 1 cm were endoscopically resected from 869 patients. Medical records of these patients were retrospectively reviewed and their clinical features and outcomes were assessed. Groups of GHPs with recurrence and those without recurrence group were compared, and univariate and multivariable analyses were performed to identify the potential risk factors for GHP recurrence.

RESULTS

A total of 104 (12.0%) patients who underwent endoscopic removal of GHPs experienced recurrence. Compared to patients without recurrent GHPs, those with recurrent GHPs showed considerably larger median polyp size (28 mm vs. 14 mm, P < 0.001), a higher proportion of multiple polyps (41.3% vs. 29.3%, P = 0.020), polyps with lobulation (63.5% vs. 40.3%, P = 0.001), and exudate (63.5% vs. 46.8%, P = 0.001). Compared to the local recurrence (n = 52) group, the metachronous recurrence (n = 52) group had larger median polyp size (20 mm vs. 16 mm, P = 0.006) as well as higher rates of polyp lobulation (86.5% vs. 40.4%, P < 0.001) and exudate (82.7% vs. 44.4%, P = 0.001). After primary GHP excision, the cumulative incidence of recurrence was 7.2%, 12.7%, and 19.6% at 2 years, 5 years, and 10 years, respectively.

CONCLUSION

The incidence of GHP recurrence following endoscopic excision increased as the follow-up period increased, especially in patients whose GHPs were large-sized, multiple, or characterized by surface exudates/lobulations.

Study of Helicobacter pylori Isolated from a High-Gastric-Cancer-Risk Population: Unveiling the Comprehensive Analysis of Virulence-Associated Genes including Secretion Systems, and Genome-Wide Association Study

BACKGROUND

The prevalence of gastric cancer in Mongolia, in East Asia, remains the highest in the world. However, most Helicobacter pylori strains in Mongolia have a less virulent Western-type CagA. We aimed to determine how H. pylori genomic variation affected gastric diseases, especially gastric cancer, based on comprehensive genome analysis.

METHODS

We identified a set of 274 virulence-associated genes in H. pylori, including virulence factor and outer membrane protein (OMP) genes, the type four secretion system gene cluster, and 13 well-known virulence gene genotypes in 223 H. pylori strains and their associations with gastric cancer and other gastric diseases. We conducted a genome-wide association study on 158 H. pylori strains (15 gastric cancer and 143 non-gastric cancer strains).

RESULTS

Out of 274 genes, we found 13 genes were variable depending on disease outcome, especially iron regulating OMP genes. H. pylori strains from Mongolia were divided into two main subgroups: subgroup (Sg1) with high risk and Sg2 with low risk for gastric cancer. The general characteristics of Sg1 strains are that they possess more virulence genotype genes. We found nine non-synonymous single nucleotide polymorphisms in seven genes that are linked with gastric cancer strains.

CONCLUSIONS

Highly virulent H. pylori strains may adapt through host-influenced genomic variations, potentially impacting gastric carcinogenesis.

The Importance of Artificial Intelligence in Upper Gastrointestinal Endoscopy

Recently, there has been a growing interest in the application of artificial intelligence (AI) in medicine, especially in specialties where visualization methods are applied. AI is defined as a computer's ability to achieve human cognitive performance, which is accomplished through enabling computer "learning". This can be conducted in two ways, as machine learning and deep learning. Deep learning is a complex learning system involving the application of artificial neural networks, whose algorithms imitate the human form of learning. Upper gastrointestinal endoscopy allows examination of the esophagus, stomach and duodenum. In addition to the quality of endoscopic equipment and patient preparation, the performance of upper endoscopy depends on the experience and knowledge of the endoscopist. The application of artificial intelligence in endoscopy refers to computer-aided detection and the more complex computer-aided diagnosis. The application of AI in upper endoscopy is aimed at improving the detection of premalignant and malignant lesions, with special attention on the early detection of dysplasia in Barrett's esophagus, the early detection of esophageal and stomach cancer and the detection of H. pylori infection. Artificial intelligence reduces the workload of endoscopists, is not influenced by human factors and increases the diagnostic accuracy and quality of endoscopic methods.

Helicobacter bizzozeronii infection in a girl with severe gastric disorders in México: case report

BACKGROUND

Gastric non-Helicobacter pylori helicobacters (NHPH) naturally colonize the stomach of animals. In humans, infection with these bacteria is associated with chronic active gastritis, peptic ulceration and MALT-lymphoma. H. bizzozeronii belongs to these NHPH and its prevalence in children is unknown.

CASE PRESENTATION

This case report describes for the first time a NHPH infection in a 20-month-old girl with severe gastric disorders in Mexico. The patient suffered from melena, epigastric pain, and bloating. Gastroscopy showed presence of a Hiatus Hill grade I, a hemorrhagic gastropathy in the fundus and gastric body, and a Forrest class III ulcer in the fundus. Histopathologic examination revealed a chronic active gastritis with presence of long, spiral-shaped bacilli in the glandular lumen. Biopsies from antrum, body and incisure were negative for presence of H. pylori by culture and PCR, while all biopsies were positive for presence of H. bizzozeronii by PCR. Most likely, infection occurred through intense contact with the family dog. The patient received a triple therapy consisting of a proton pump inhibitor, clarithromycin, and amoxicillin for 14 days, completed with sucralfate for 6 weeks, resulting in the disappearance of her complaints.

CONCLUSION

The eradication could not be confirmed, although it was suggested by clear improvement of symptoms. This case report further emphasizes the zoonotic importance of NHPH. It can be advised to routinely check for presence of both H. pylori and NHPH in human patients with gastric complains.

Microscopic Colitis: Pathogenesis and Diagnosis

Microscopic colitis is a type of inflammatory bowel disease and is classified as either collagenous colitis or lymphocytic colitis. The typical presentation is chronic watery diarrhea. The disease occurs more frequently in women aged 60-65 years and is increasing in incidence. The pathophysiology of microscopic colitis remains poorly understood and has not been well-described with possible several pathogeneses. To date, the diagnosis of microscopic colitis depends on histological tissue obtained during colonoscopy. Other non-invasive biomarkers, such as inflammatory markers and fecal biomarkers, have been studied in microscopic colitis, but the results remains inconclusive. The approach to chronic diarrhea is important and being able to differentiate chronic diarrhea in patients with microscopic colitis from other diseases, such as inflammatory bowel disease, functional diarrhea, and malignancy, by using non-invasive biomarkers would facilitate patient management. The management of microscopic colitis should be based on each individual's underlying pathogenesis and involves budesonide, bile acid sequestrants, or immunosuppressive drugs in refractory cases. Cigarette smoking and certain medications, especially proton pump inhibitors, should be eliminated, when possible, after the diagnosis is made.

Diagnostic yield for video capsule endoscopy in gastrointestinal graft- versus -host disease: a systematic review and metaanalysis

BACKGROUND

The gastrointestinal tract is the second most involved organ for graft-versus-host disease where involvement of the small intestine is present in 50% of the cases. Therefore, the use of a non-invasive investigation i.e., video capsule endoscopy (VCE) seems ideal in the diagnostic work-up, but this has never been systematically evaluated before.

OBJECTIVE

The aim of this systematic review was to determine the efficacy and safety of VCE, in comparison with conventional endoscopy in patients who received hematopoietic stem cell transplantation.

METHOD

Databases searched were PubMed, Scopus, EMBASE, and Cochrane CENTRAL. All databases were searched from their inception date until June 17, 2022. The search identified 792 publications, of which 8 studies were included in our analysis comprising of 232 unique patients. Efficacy was calculated in comparison with the golden standard i.e., histology. Risk of bias assessment was performed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

RESULTS

The pooled sensitivity was higher for VCE at 0.77 (95% CI: 0.60-0.89) compared to conventional endoscopy 0.62 (95% CI: 0.47-0.75) but the difference was not statistically significant (p = 0.155, Q = 2.02). Similarly, the pooled specificity was higher for VCE at 0.68 (95% CI: 0.46-0.84) than for conventional endoscopy at 0.58 (95% CI: 0.40-0.74) but not statistically significant (p = 0.457, Q = 0.55). Moreover, concern for adverse events such as intestinal obstruction or perforation was not justified since none of the capsules were retained in the small bowel and no perforations occurred in relation to VCE. A limitation to the study is the retrospective approach seen in 50% of the studies.

CONCLUSION

The role of video capsule endoscopy in diagnosing or dismissing graft-versus-host disease is not yet established and requires further studies. However, the modality appears safe in this cohort.

Evaluation of non-gastric upper gastrointestinal system polyps: an epidemiological assessment

Non-gastric upper gastrointestinal system polyps are detected rarely and mostly incidentally during upper gastrointestinal endoscopy. While the majority of lesions are asymptomatic and benign, some lesions have the potential to become malignant, and may be associated with other malignancies. Between May 2010 and June 2022, a total of 127,493 patients who underwent upper gastrointestinal endoscopy were retrospectively screened. Among these patients, those who had polyps in the esophagus and duodenum and biopsied were included in the study. A total of 248 patients with non-gastric polyps were included in this study. The esophageal polyp detection rate was 80.00/100,000, while the duodenal polyp detection rate was 114.52/100,000. In 102 patients (41.1%) with esophageal polyps, the mean age was 50.6 ± 15.1, and 44.1% (n = 45) were male. The most common type of polyps was squamous papilloma (n = 61, 59.8%), followed by inflammatory papilloma (n = 18, 17.6%). In 146 patients (58.9%) with duodenal polyps, the mean age of patients was 58.3 ± 16.5, and 69.8% (n = 102) were male. Brunner's gland hyperplasia, inflammatory polyp, ectopic gastric mucosa, and adenomatous polyp were reported to be the most prevalent types of polyps in the duodenum overall (28.1%, 27.4%, 14.4%, and 13.7%, respectively). It is crucial to identify rare non-gastric polyps and create an effective follow-up and treatment plan in the era of frequently performed upper gastrointestinal endoscopies. The epidemiological assessment of non-gastric polyps, as well as a follow-up and treatment strategy, are presented in this study.

Image-enhanced endoscopy for real-time differentiation between hyperplastic and fundic gland polyps in the stomach

BACKGROUND

Fundic gland polyps (FGP) of stomach are benign, while some hyperplastic polyps (HP) may harbor dysplasia or malignancy. Conventional white light endoscopy (WLE) cannot reliably distinguish FGP from HP. We investigated the role of image-enhanced endoscopy in differentiating FGP from HP.

METHODS

Patients with gastric polyps were recruited prospectively. The characteristics of the polyps were assessed using WLE and magnification narrow band imaging (mNBI). The microsurface, intervening space (IS), and microvascular (V) features of polyps were evaluated on mNBI. The pattern characteristic of FGP and HP were determined. Histopathology of polyps was the gold standard for diagnosis. Finally, in the validation phase, five endoscopists applied the characteristic features identified in this study to predict the type of gastric polyp and their performance was assessed.

RESULTS

Forty-five patients with a total of 70 gastric polyps (HP-46, FGP-24) were included in this study. On mNBI, the pattern characteristic of HP included peripheral curved type of white structures forming large circular/villous loops (microsurface), enlarged intervening space, and microvessels appearing as dark patches in the intervening space (p<0.001 vs. FGP). These were noted in 95.7% HP. In contrast, 95.8% FGP had a pattern characterized by dotted/elliptical/tubular white structures (microsurface), normal width of intervening space, and microvessels surrounding the white structures in a network pattern. This IS-V pattern classification had an accuracy of >90% in the validation phase with intra-class correlation coefficient of 0.95. The accuracy of mNBI was higher than WLE (97.1% vs. 67%) in predicting the type of gastric polyp.

CONCLUSIONS

Image-enhanced endoscopy with mNBI (IS-V pattern) performs very well in differentiating HP from FGP.

Histological assessment of new cholangioscopy-guided forceps in ERCP biliary stricture sampling: a blinded comparative study

Background and study aims  Obtaining quality tissue during ERCP biliary stricture sampling is of paramount importance for a timely diagnosis. While single-operator cholangioscopy (SOC)-guided biopsies have been suggested to be the superior biliary tissue acquisition modality given direct tissue visualization, less is known about the specimen histological quality. We aimed to analyze the specimen quality of SOC biopsies and compare the new generation forceps with prior "legacy" forceps. Patients and methods  Patients who underwent SOC from January 2017-August 2021 for biliary sampling were reviewed. In February 2020, the SOC-guided biopsy forceps were changed from legacy SpyBite to the SpyBite Max forceps (max). Specimens were assessed by blinded pathologists for crush artifact (none, mild, or severe) and gross size (greatest dimension in mm). Crush artifact and gross size were compared between the two groups. The diagnostic performance characteristics for cholangiocarcinoma (CCA), were assessed in an exploratory fashion. Results  Eighty-one patients (max = 27, legacy = 54) with similar baseline characteristics were included in this study. On blinded pathological assessment, 58 % had crush artifact, without significant differences between the two groups (Max 63 % vs. Legacy 56 %; P  = 0.64). A similar mean specimen size was found (max 3 mm vs. legacy 3.2 mm; P  = 0.24). The overall prevalence of CCA was 40 %. The sensitivity, specificity, positive predictive value, and negative predictive value of the entire cohort using a combination of cytology, fluorescence in situ hybridization, and SOC-guided biopsies were 78.1 %, 91.8 %, 86.2 %, and 86.5 %, respectively. No difference between legacy or max groups was found. Conclusions  A high rate of crush artifact was found in SOC-guided biopsy specimens. Further investigation regarding proper biopsy technique and handling is necessary to increase the diagnostic yield with SOC-guided biopsies.

Estimating the optimum number of colon biopsies for diagnosing microscopic colitis: a systematic review

Microscopic colitis (MC) is an inflammatory disease of the colon characterized by persistent watery, nonbloody diarrhea. Subtypes of MC include collagenous and lymphocytic MC. Microscopic examination of colon tissue is crucial to confirming the diagnosis because the colonic mucosa often appears normal during flexible sigmoidoscopy or colonoscopy. We aim to determine the optimal sites and minimum number of colon biopsies required to diagnose MC from published studies. We systematically searched PubMed, Web of Science, Scopus, and Cochrane databases from inception until October 2020 using the following keywords: microscopic, lymphocytic, collagenous, colitis, biopsy, and biopsies. We screened the search results for eligibility and extracted data from the included studies. We pooled the numbers of biopsies provided by each study to calculate the mean number of biopsies, SD, and SEM. We included three retrospective cohort studies with 356 patients (148 collagenous, 192 lymphocytic, and 16 mixed), and the total number of biopsies were 1854. The mean number of biopsies that were recommended by the included studies are 4, 4, and 9, respectively. The pooled mean ± SD is 5.67 ± 2.89. The included studies reported that biopsies from the ascending colon (AC) and descending colon (DC) had the highest diagnostic rates. To ensure a high level of certainty in diagnosing MC, a total of six biopsies should be taken from the AC and DC (3 AC and 3 DC). However, special care should be directed toward differentiating MC from other forms of colitis. In addition, detailed and comparative studies are needed to provide stronger recommendations to diagnose MC.

Fungal Microbiota Dysbiosis and Ecological Alterations in Gastric Cancer

Changes in bacteriome composition have a strong association with gastric cancer (GC). However, the relationship between stomach fungal microbiota composition and human host immune factors remains largely unknown. With high-throughput internal transcribed spacer region 2 (ITS2) sequencing, we characterized gastric fungal microbiome among the GC (n = 22), matched para-GC (n = 22), and healthy individuals (n = 11). A total of 4.5 million valid tags were generated and stratified into 1,631 operational taxonomic units (OTUs), and 10 phyla and 301 genera were identified. The presence of GC was associated with a distinct gastric fungal mycobiome signature, characterized by a decreased biodiversity and richness and significant differences in fungal composition. In addition, fungal dysbiosis was reflected by the increased ratio of Basidiomycota to Ascomycota and a higher proportion of opportunistic fungi, such as Cutaneotrichosporon and Malassezia, as well as the loss of Rhizopus and Rhodotorula during the progression of cancers. A panel of GC-associated fungi (e.g., Cutaneotrichosporon and Rhodotorula) was found to adequately exhibit diagnostic value. Furthermore, the mRNA levels of cytokines and chemokines were detected and correlated with the specific fungal dysbiosis, indicating the possible mechanism of GC. This study reveals GC-associated mycobiome dysbiosis characterized by altered fungal composition and ecology and suggests that the fungal mycobiome might play a role in the pathogenesis of GC.

Gastric polyps: a 10-year analysis of 18,496 upper endoscopies

Background/aims

Gastric polyps (GPs) are usually asymptomatic lesions of the upper gastrointestinal tract observed in 1–3% of esophagogastroduodenoscopies (EGD). Most GPs are benign. The aim of this study was to precise the frequency of different types of gastric polyps in our population, and to analyze their possible association with other factors.

Materials and methods

A total of 18,496 consecutive patients undergoing EGD over a 10-year period (between 2007 and 2018) in a tertiary hospital were retrospectively reviewed. Eighty-six patients diagnosed with gastric polyps were analysed. Demographics, medical history of the patients, and indication for gastroscopy were collected. Morphological, histological characteristics of polyps, and therapeutic management data were also collected.

Results

GPs were found in 86 out of 18,496 (0.46%) reviewed EGD, corresponding to a total of 141 polyps. There were 64 female (74.4%) and 22 male patients (25.6%) with a sex ratio (M/F) of 0.34. The average age was 58.1 years. One hundred and forty one polyps were included, and histopathology was obtained on 127 GPs. The most common location was the fundus (59.6%) and 48.9% were smaller than 5 mm. The polyp was unique in 75.6% of cases. According to Paris classification, 80% of the polyps were sessile (Is). Hyperplastic polyps were the most common (55.9%), followed by sporadic fundic gland polyps observed in 23 patients (18.1%), 7 (5.5%) were adenomas and 4 (3.1%) were neuroendocrine tumors type 1. The following factors were associated with hyperplastic polyps: anemia (p = 0.022), single polyp (p = 0.025) and size ≥ 5 mm (p = 0.048). Comparing hyperplastic polyps’ biopsies to resected polyps, no difference was found in the evolutionary profile of the 2 groups. A size less than 10 mm (p = 0.013) was associated with fundic gland polyps. Sixty polyps (47.2%) were treated by cold forceps, 19 (15%) treated by a mucosal resection and 15 (11.8%) with diathermic snare. Five procedural bleeding incidents were observed (3.9%). Only the use of anticoagulant treatment was associated with a high bleeding risk (p = 0.005). The comparative histological study between specimens of biopsied GPs and endoscopic polypectomy led to an overall agreement of 95.3%.

Conclusion

In our study, the GPs frequency was 0.36%. Hyperplastic polyps and fundic gland are the most common in our country. The high frequency of Helicobacter pylori infection in our patients and in our area may explain the high frequency of HP.

Endoscopic tissue sampling - Part 1: Upper gastrointestinal and hepatopancreatobiliary tracts. European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends that, where there is a suspicion of eosinophilic esophagitis, at least six biopsies should be taken, two to four biopsies from the distal esophagus and two to four biopsies from the proximal esophagus, targeting areas with endoscopic mucosal abnormalities. Distal and proximal biopsies should be placed in separate containers.Strong recommendation, low quality of evidence. 2: ESGE recommends obtaining six biopsies, including from the base and edge of the esophageal ulcers, for histologic analysis in patients with suspected viral esophagitis.Strong recommendation, low quality of evidence. 3: ESGE recommends at least six biopsies are taken in cases of suspected advanced esophageal cancer and suspected advanced gastric cancer.Strong recommendation, moderate quality of evidence. 4: ESGE recommends taking only one to two targeted biopsies for lesions in the esophagus or stomach that are potentially amenable to endoscopic resection (Paris classification 0-I, 0-II) in order to confirm the diagnosis and not compromise subsequent endoscopic resection.Strong recommendation, low quality of evidence. 5: ESGE recommends obtaining two biopsies from the antrum and two from the corpus in patients with suspected Helicobacter pylori infection and for gastritis staging.Strong recommendation, low quality of evidence. 6: ESGE recommends biopsies from or, if endoscopically resectable, resection of gastric adenomas.Strong recommendation, moderate quality of evidence. 7: ESGE recommends fine-needle aspiration (FNA) and fine-needle biopsy (FNB) needles equally for sampling of solid pancreatic masses.Strong recommendation, high quality evidence. 8: ESGE suggests performing peroral cholangioscopy (POC) and/or endoscopic ultrasound (EUS)-guided tissue acquisition in indeterminate biliary strictures. For proximal and intrinsic strictures, POC is preferred. For distal and extrinsic strictures, EUS-guided sampling is preferred, with POC where this is not diagnostic.Weak recommendation, low quality evidence. 9: ESGE suggests obtaining possible non-neoplastic biopsies before sampling suspected malignant lesions to prevent intraluminal spread of malignant disease.Weak recommendation, low quality of evidence. 10: ESGE suggests dividing EUS-FNA material into smears (two per pass) and liquid-based cytology (LBC), or the whole of the EUS-FNA material can be processed as LBC, depending on local experience.Weak recommendation, low quality evidence.

Endoscopy biopsy is not efficiency enough for diagnosis of mucinous colorectal adenocarcinoma

BACKGROUND

Endoscopy biopsy (EB) is the standard diagnostic method for colorectal cancer (CRC), whereas its accuracy and efficiency in mucinous adenocarcinoma (MAC) initial diagnosis is unclear.

METHODS

The initial EB and postoperative specimen (PS) pathological diagnosis of MAC from two centers were retrospectively collected and analyzed. The accuracy and efficiency of initial EB compared with PS pathological diagnosis were analyzed. The potential factors which would affect the initial EB diagnosis of MAC were analyzed.

RESULTS

280 and 78 eligible cases were enrolled in this study from two centers respectively. The initial EB diagnosis accuracy for MAC were 84.62% and 83.33%. However, among the cases of PS diagnosis with MAC, the diagnostic efficiency of initial EB was only 36.49% and 32.50% respectively. Lower tumor differentiation and more EB number were associated with an increased probability for the EB diagnosis of MAC, but only tumor differentiation was an independent diagnositic factor for EB in the two cohorts.

CONCLUSIONS

The accuracy of initial EB with MAC is high, but the diagnostic efficiency was extremely low. Tumor differentiation and EB number were associated with the diagnosis efficiency of MAC before surgery.

No Microscope Needed: A Macroscopic Presentation of Collagenous Colitis

Microscopic colitis (MC) is a common cause of chronic secretory diarrhea with variable etiologies, including nonsteroidal anti-inflammatory drugs. As its name implies, the diagnosis requires consistent histopathologic findings that typically accompany normal-appearing mucosa. However, accumulating evidence suggests that the presence of distinct endoscopic features is associated with MC. We present a case of MC that highlights the importance of recognizing these macroscopic findings because they can aid in diagnosis and have significant management implications.

Advantage of 16S rRNA amplicon sequencing in Helicobacter pylori diagnosis

BACKGROUND

16S rRNA amplicon sequencing is an accurate method of detecting microbial infection without culture. It is unclear if sequencing has additional benefits over routine diagnostic methods for Helicobacter pylori testing.

METHODS

We enrolled Mongolian volunteers with dyspepsia. Using routine diagnostic methods, positive H. pylori was defined as positive results on histology/immunohistochemistry, culture, rapid urease test, or serology; negative H. pylori was defined by negative results from all these tests. We performed 16S rRNA sequencing on gastric biopsy specimens and calculated cutoffs for operational taxonomic units (OTUs) and relative abundance (RA) to define positive results using ROC curves.

RESULTS

We examined 161 individuals with a mean age of 43.6 years, and 64.6% were women. Using routine diagnostic methods, 122 (75.8%) participants were H. pylori positive, the sensitivity and specificity for 16S rRNA sequencing were 94.3% and 82.1% or 93.4% and 82.1% when cutoff values were set to 1113 (OTU number) or 4.4% RA, respectively (both p < .001). When combining the validated values, the concordance rate was high (91.1%); however, 16S rRNA sequencing had additional positive yield in 9 cases (5.6%) compared with routine diagnostic methods, and much greater additional positive yield compared to histopathology/IHC, culture, RUT, serology separately with 12 (7.4%), 37 (23.0%) and 43 (26.7%).

CONCLUSION

16S rRNA amplicon sequencing detects potentially important proportion of H. pylori-positive cases that test negative with routine diagnostic methods. The quantitative number of H. pylori can help to understand how it can be changing by diseases and RA give opportunity to understand how H. pylori communicate with other microbiota.

Is Endoscopic Assessment of the Esophagus and Stomach Enough to Determine the Need for Biopsy at These Sites in Pediatric Patients Undergoing Endoscopy for Elevated TTG?

OBJECTIVES

The goal of our study was to determine whether visual assessment of the esophagus and stomach could predict abnormal histology and determine the frequency of interventions based on biopsies in patients undergoing endoscopy for elevated tissue transglutaminase immunoglobulin A antibody (TTG).

METHODS

Pathology records were searched for patients with biopsy performed for elevated TTG. Pathology report, endoscopy report, and follow-up were obtained and slides from the duodenum reviewed. Pathology was considered gold standard for sensitivity and specificity calculations.

RESULTS

240 patients were included. 215 patients had esophageal biopsies performed. Esophageal endoscopic visual assessment had sensitivity of 47% and specificity of 93% for abnormal histology. 16(7%) patients had therapy or referral related to results and, of these, 6(38%) had visually normal endoscopy. 237 biopsies were performed of stomach. Gastric endoscopic visual assessment had a sensitivity and specificity of 20% and 87%. 24(10%) patients had therapy based on findings and, of these, 12 (50%) had visually normal endoscopy.

CONCLUSIONS

Endoscopic assessment of esophagus and stomach has low sensitivity and high specificity for pathologic abnormalities when indication for endoscopy is elevated TTG. When endoscopy is visually normal clinical interventions based on biopsy are rare, and foregoing biopsy may be considered.

Quality in diagnostic upper gastrointestinal endoscopy for the detection and surveillance of gastric cancer precursor lesions: Position paper of AEG, SEED and SEAP

This position paper, sponsored by the Asociación Española de Gastroenterología [Spanish Association of Gastroenterology], the Sociedad Española de Endoscopia Digestiva [Spanish Gastrointestinal Endoscopy Society] and the Sociedad Española de Anatomía Patológica [Spanish Anatomical Pathology Society], aims to establish recommendations for performing an high quality upper gastrointestinal endoscopy for the screening of gastric cancer precursor lesions (GCPL) in low-incidence populations, such as the Spanish population. To establish the quality of the evidence and the levels of recommendation, we used the methodology based on the GRADE system (Grading of Recommendations Assessment, Development and Evaluation). We obtained a consensus among experts using a Delphi method. The document evaluates different measures to improve the quality of upper gastrointestinal endoscopy in this setting and makes recommendations on how to evaluate and treat the identified lesions. We recommend that upper gastrointestinal endoscopy for surveillance of GCPL should be performed by endoscopists with adequate training, administering oral premedication and use of sedation. To improve the identification of GCPL, we recommend the use of high definition endoscopes and conventional or digital chromoendoscopy and, for biopsies, NBI should be used to target the most suspicious areas of intestinal metaplasia. Regarding the evaluation of visible lesions, the risk of submucosal invasion should be evaluated with magnifying endoscopes and endoscopic ultrasound should be reserved for those with suspected deep invasion. In lesions amenable to endoscopic resection, submucosal endoscopic dissection is considered the technique of choice.

The indications for biopsy in routine upper gastrointestinal endoscopy

This review describes the indications and contraindications for endoscopic biopsy, in routine practice, of the upper gastrointestinal (GI) tract. We accept that this review provides grounds for controversy, as our stance in certain situations is counter to some national guidelines. Nevertheless, we provide evidence to support our viewpoints, especially on efficiency and economic grounds. We describe the particular controversies concerning the biopsy assessment of Barrett's oesophagus, chronic gastritis and the duodenum in the investigation of coeliac disease. We accept that there are indications for more extensive upper GI biopsy protocols in children than in adults; the latter constitute our main focus in this article. We would encourage detailed discussion between pathologists and their endoscopy colleagues about the indications, or lack of them, for routine upper GI endoscopic biopsy, as studies have shown that adherence to agreed guidelines has resulted in a very considerable diminution in the biopsy workload without compromising patient management. Furthermore, where biopsy is indicated, we emphasise the importance of accompanying clinical information provided to the pathologist, in particular regarding biopsy site(s), and regular feedback to endoscopists to improve and maintain the quality of such information. Finally, local dialogue is also advised, when necessary, to indicate to endoscopists the need to appropriately segregate biopsies into separate, individually labelled specimens, to maximise the information that can be derived by pathological evaluation and thereby improve the quality of the final pathology report.

The role of histopathology in the diagnosis and management of coeliac disease and other malabsorptive conditions

Most absorption of nutrients takes place in the proximal small intestine, and the most common disorders leading to malabsorption are associated with a morphological abnormality in the duodenal mucosa that is appreciable in histological sections of biopsy specimens. Coeliac disease is the most well-known example, causing intraepithelial lymphocytosis, inflammation and villous atrophy in the duodenum. Remarkably similar inflammatory changes can be induced by other processes, including medications, e.g. angiotensin II receptor blockers and immune checkpoint inhibitors, immune dysregulation disorders, e.g. common variable immunodeficiency and autoimmune enteropathy, infections, collagenous sprue, and tropical sprue. However, there are often subtle histological differences from coeliac disease in the type of inflammatory infiltrate, the presence of crypt apoptosis, and the extent and type of inflammation beyond the duodenum. The clinical setting and serological investigation usually allow diagnostic separation, but some cases remain challenging. Histopathology is also important in assessing the response to treatment, such as the change in villous architecture caused by a gluten-free diet, or the response to cessation of a potentially causative medication. This review examines the practical role that histopathology of duodenal biopsy specimens plays in the assessment and management of inflammatory malabsorptive processes of the proximal small intestine, with a particular emphasis on coeliac disease.

Quality indicators in gastroscopy. Gastroscopy procedure

Within the project "Quality indicators in digestive endoscopy", pioneered by the Spanish Society for Digestive Diseases (SEPD), the objective of this research is to suggest the structure, process, and results procedures and indicators necessary to implement and assess quality in the gastroscopy setting. First, a chart was designed with the steps to be followed during a gastroscopy procedure. Secondly, a team of experts in care quality and/or endoscopy performed a qualitative review of the literature searching for quality indicators for endoscopic procedures, including gastroscopies. Finally, using a paired analysis approach, a selection of the literature obtained was undertaken. For gastroscopy, a total of nine process indicators were identified (one preprocedure, eight intraprocedure). Evidence quality was assessed with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) classification scale.

Biopsies From Ascending and Descending Colon Are Sufficient for Diagnosis of Microscopic Colitis

BACKGROUND & AIMS

Lymphocytic and collagenous colitis are types of microscopic colitis (MC) that commonly cause chronic watery diarrhea, but there are no macroscopic features of MC that can be detected during colonoscopy. Endoscopists therefore often collect multiple random colonic biopsies, potentially oversampling, increasing times of colonoscopy and slide review. We sought to identify sites from which biopsies could be taken and analyzed to identify patients with MC with a high level of sensitivity and determine the appropriate number of biopsies to take at these sites.

METHODS

We performed a retrospective study using biopsies from 101 consecutive patients with MC (52 cases of collagenous colitis, 42 cases of lymphocytic colitis, 7 combined cases), without comorbidities, from 2017 through 2018. Slides were reviewed, and the proportion of biopsies that were diagnostic of MC were calculated at each biopsy site.

RESULTS

The proportions of biopsy fragments from each site of the colon found to be positive for MC were as follows: cecum, 90.0%; ascending colon, 96.9%; hepatic flexure, 77.8%; transverse colon, 95.7%; splenic flexure, 75.0%; descending colon, 85.0%; sigmoid colon, 90.9%; and rectum, 82.2%. For biopsies labeled random, 95.7% were positive for MC. When findings from ascending and descending colon biopsies were combined, 100% of MC cases were detected.

CONCLUSIONS

MC can be detected with certainty by analyzing biopsies from the ascending and descending colon. Fewer biopsies than were collected from our cases are sufficient for diagnosis. We propose a Western protocol (taking 2 biopsies from each of the ascending and descending colon) in evaluation of patients for MC.

Antibiotic resistance and clonal relatedness of Helicobacter pylori strains isolated from stomach biopsy specimens in northeast of Iran

BACKGROUND

Resistant Helicobacter pylori to commonly used antimicrobial agents are associated with severe upper gastrointestinal disorders. To provide an epidemiological picture of H pylori and characterize the resistance pattern and genetic variation of clinical isolates, stomach biopsies from patients with functional dyspepsia were evaluated in northeast of Iran.

MATERIALS AND METHODS

In this study, 80 patients were recruited. Finally, fifty H pylori strains were isolated from antrum and corpus biopsies by culturing on Columbia agar. All strains were identified by standard laboratory procedures. Susceptibility testing of antibiotics was performed using minimum inhibitory concentration test. Allele-specific primer (ASP)-PCR of 23S rRNA which associated with clarithromycin resistance was done among resistant strains. Moreover, cagA gene and polymorphism in vacA were detected. Random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) was applied to investigate the genetic variations among all strains.

RESULTS

Antibiotic resistance pattern of H pylori strains was as follows: 68% (34/50) to metronidazole, 50% (25/50) to rifampicin, 30% (15/50) to amoxicillin, 28% (14/50) to levofloxacin, 22% (11/50) to clarithromycin, and 16% (8/50) to tetracycline. Multidrug-resistant strains were observed in 19 strains (38%). ASP-PCR of 23S rRNA showed four strains had A2143G mutation, six strains had A2142G mutation, and one strain had a Wt+A2143G mutation. Amplification of virulence-associated genes revealed that cagA was present in 27 isolates (54%) and vacA in 36 isolates (72%). The most common genotype of H pylori was vacA s1am2 (40%) followed by vacA s2m2 (14%), vacA s1am1 (12%), vacA s1bm1 (4%), and vacA s1bm2 (2%). DNA fingerprinting pattern indicated a high heterogeneity among isolated strains.

CONCLUSION

An alarming level of resistance to metronidazole and rifampicin and high heterogeneity among H pylori isolates highlighted the importance of continued monitoring of antimicrobial susceptibility and epidemiological surveillance of this pathogen.

Gastric mucosal microbiota in a Mongolian population with gastric cancer and precursor conditions

BACKGROUND

Incidence and mortality of gastric cancer (GC) are high in Mongolia despite Helicobacter pylori in the Mongolian population being less virulent.

AIM

To evaluate gastric bacterial microbiota profiles in patients with GC and its precursor histological conditions.

METHODS

We conducted a case-control study among 48 GC and 120 noncancer patients (20 normal gastric mucosa [control], 20 gastritis, 40 with atrophy and 40 intestinal metaplasia [IM]). We performed 16S rRNA gene amplicon sequencing and compared taxonomic and functional prediction profiles based on the diagnosis group and H pylori infection status.

RESULTS

The highest overall bacterial alpha diversity metrics were observed in the control group, followed by the IM and cancer groups. The gastritis and atrophy groups had the least diversity. Lactobacilli and Enterococci were the dominant genus in several cancer patients especially in the absence of H pylori. In addition, Carnobacterium, Glutamicibacter, Paeniglutamicibacter, Fusobacterium and Parvimonas were associated with GC regardless of H pylori infection. Firmicutes were decreased in the gastritis and atrophy groups and increased in the IM and cancer groups. The functional metabolic activity of the Embden-Meyerhof-Parnas pathway and the utilization of sugar, were significantly increased in cancer group compared with the noncancer group.

CONCLUSION

Microbial factors other than H pylori may play a role in Mongolian GC. We identified novel associations between GC and the genera Enterococcus, Lactobacillus, Carnobacterium, Glutamicibacter, Paeniglutamicibacter, Fusobacterium, and Parvimonas.

Lesion Retrieval, Specimen Handling, and Endoscopic Marking in Colonoscopy

Retrieval of lesions after endoscopic polypectomy enables histopathologic analysis and guides future surgical management and endoscopic surveillance intervals. Various techniques and devices have been described with distinct advantages and disadvantages to accomplish retrieval. Appropriate histopathologic analysis depends on lesion handling and preparation. How lesions are handled further depends on size, endoscopic appearance, and removal technique. Endoscopic marking or tattooing is a well-described process that uses dye mediums to leave longstanding marks in the colon. Techniques, dye mediums, and locations within the colon influence tattoo approach.

The Mexican consensus on non-cardiac chest pain

INTRODUCTION

Non-cardiac chest pain is defined as a clinical syndrome characterized by retrosternal pain similar to that of angina pectoris, but of non-cardiac origin and produced by esophageal, musculoskeletal, pulmonary, or psychiatric diseases.

AIM

To present a consensus review based on evidence regarding the definition, epidemiology, pathophysiology, and diagnosis of non-cardiac chest pain, as well as the therapeutic options for those patients.

METHODS

Three general coordinators carried out a literature review of all articles published in English and Spanish on the theme and formulated 38 initial statements, dividing them into 3 main categories: (i)definitions, epidemiology, and pathophysiology; (ii)diagnosis, and (iii)treatment. The statements underwent 3rounds of voting, utilizing the Delphi system. The final statements were those that reached >75% agreement, and they were rated utilizing the GRADE system.

RESULTS AND CONCLUSIONS

The final consensus included 29 statements. All patients presenting with chest pain should initially be evaluated by a cardiologist. The most common cause of non-cardiac chest pain is gastroesophageal reflux disease. If there are no alarm symptoms, the initial approach should be a therapeutic trial with a proton pump inhibitor for 2-4weeks. If dysphagia or alarm symptoms are present, endoscopy is recommended. High-resolution manometry is the best method for ruling out spastic motor disorders and achalasia and pH monitoring aids in demonstrating abnormal esophageal acid exposure. Treatment should be directed at the pathophysiologic mechanism. It can include proton pump inhibitors, neuromodulators and/or smooth muscle relaxants, psychologic intervention and/or cognitive therapy, and occasionally surgery or endoscopic therapy.

Western-Type Helicobacter pylori CagA are the Most Frequent Type in Mongolian Patients

Helicobacter pylori infection possessing East-Asian-type CagA is associated with carcinogenesis. Mongolia has the highest mortality rate from gastric cancer. Therefore, we evaluated the CagA status in the Mongolian population. High risk and gastric cancer patients were determined using endoscopy and histological examination. H. pylori strains were isolated from different locations in Mongolia. The CagA subtypes (East-Asian-type or Western-type, based on sequencing of Glu-Pro-Ile-Tyr-Ala (EPIYA) segments) and vacA genotypes (s and m regions) were determined using PCR-based sequencing and PCR, respectively. In total, 368 patients were examined (341 gastritis, 10 peptic ulcer, and 17 gastric cancer). Sixty-two (16.8%) strains were cagA-negative and 306 (83.1%) were cagA-positive (293 Western-type, 12 East-Asian-type, and one hybrid type). All cagA-negative strains were isolated from gastritis patients. In the gastritis group, 78.6% (268/341) had Western-type CagA, 2.9% (10/341) had East-Asian-type, and 18.2% (61/341) were cagA-negative. However, all H. pylori from gastric cancer patients possessed Western-type CagA. Histological analyses showed that East-Asian-type CagA was the most virulent strains, followed by Western-type and cagA-negative strains. This finding agreed with the current consensus. CagA-positive strains were the most virulent type. However, the fact that different CagA types can explain the high incidence of gastric cancer might be inapplicable in Mongolia.

Gastric Microbiota in Helicobacter pylori-Negative and -Positive Gastritis Among High Incidence of Gastric Cancer Area

Helicobacter pylori (H. pylori) related chronic gastritis is a well-known major etiological factor for gastric cancer development. However, H. pylori-negative gastritis (HpN) is not well described. We aimed to examine gastric mucosal microbiota in HpN compared to H. pylori-positive gastritis (HpP) and H. pylori-negative non-gastritis group (control). Here, we studied 11 subjects with HpN, 40 with HpP and 24 controls. We performed endoscopy with six gastric biopsies. Comparison groups were defined based on strict histological criteria for the disease and H. pylori diagnosis. We used 16S rRNA gene amplicon sequencing to profile the gastric microbiota according to comparison groups. These results demonstrate that the HpP group had significantly lower bacterial richness by the operational taxonomic unit (OTU) counts, and Shannon and Simpson indices as compared to HpN or controls. The linear discriminant analysis effect size analysis showed the enrichment of Firmicutes, Fusobacteria, Bacteroidetes and Actinobacteria at phylum level in the HpN group. In the age-adjusted multivariate analysis, Streptococcus sp. and Haemophilus parainfluenzae were at a significantly increased risk for HpN (odds ratio 18.9 and 12.3, respectively) based on abundance. Treponema sp. was uniquely found in HpN based on occurrence. In this paper, we conclude that Streptococcus sp., Haemophilus parainfluenzae and Treponema sp. are candidate pathogenic bacterial species for HpN. These results if confirmed may have important clinical implications.

Management of microscopic colitis: challenges and solutions

Microscopic colitis (MC) is a chronic inflammatory bowel disease characterized by nonbloody diarrhea in the setting of normal appearing colonic mucosa. MC has two main subtypes based on histopathologic features, collagenous colitis and lymphocytic colitis. Management of both subtypes is the same, with treatment goal of reducing the number of bowel movements and improving consistency. First-line treatment involves counseling the patient about decreasing their risk factors, like discontinuing smoking and avoiding medications with suspected association such as NSAIDs, proton pump inhibitor, ranitidine, and sertraline. Starting loperamide for immediate symptomatic relief is used as an adjunct to therapy with glucocorticoids. Budesonide is considered first-line treatment for MC given its favorable side effect profile and good efficacy, though relapse rates are high. Systemic glucocorticoids should be reserved to patients unable to take budesonide. In glucocorticoid refractory disease, medications that have been tried include cholestyramine, bismuth salicylate, antibiotics, probiotics, aminosalicylates, immunomodulators, and anti-tumor necrosis factor-alpha inhibitors. More research is needed for the creation of a systematic stepwise approach for relapsing and refractory disease.

Management patterns of gastric polyps in the United States

OBJECTIVE

Recent guidelines on endoscopic sampling recommend complete gastric polyp removal for solitary fundic polyps >10 mm, hyperplastic polyps >5 mm and all adenomatous polyps. We aim to describe endoscopic approach to polyps in the time period prior to the American Society of Gastrointestinal Endoscopy (ASGE) guidelines and to identify opportunities for clinical practice improvements.

DESIGN

Retrospective review of the Clinical Outcome Research Initiative (CORI) database, including all oesophagogastroduodenoscopies (OGDs). Reviewers grouped interventions during procedures based on instruments used for polyp sampling by forceps or snare polypectomy. Logistic regression estimated the effect of variables of interest on method of polypectomy.

RESULTS

Of 783 037 OGDs reported in the CORI database, 25 670 (3.3%) described gastric polyps and met the inclusion criteria. Mean gastric polyp size was 6.5±4.9 mm, and 46.2% and 14.5% were located in the corpus and antrum, respectively. Polyps in the forceps group were smaller than polyps in the snare group (5.7±4.0 mm vs 9.3±6.4 mm, respectively, p<0.001). We identified 1056 polyps (41.3%) >10 mm that only underwent forceps biopsy. Forceps were used more frequently in the gastric fundus.

CONCLUSIONS

Snare polypectomy was underused in gastric polyps, per current ASGE guidelines. Anatomical location and endoscopic features of polyps were important predictors of the approach to gastric polypectomy.

Evaluation of serum markers for gastric cancer and its precursor diseases among high incidence and mortality rate of gastric cancer area

BACKGROUND

Mongolia has the highest mortality rate of gastric cancer. The early detection of cancer and down-staging screening for high risk patients are essential. Therefore, we aimed to validate serum markers for stratifying patients for further management.

METHODS

Endoscopy and histological examination were performed to determine high risk and gastric cancer patients. Rapid urease test, culture and histological tests were performed to diagnose Helicobacter pylori infection. Serum pepsinogen (PG) I and II and anti-H. pylori IgG were measured by ELISA. Receiver Operating Characteristic analysis was used to extract the best cut-off point.

RESULTS

Totally 752 non-cancer and 50 consecutive gastric cancer patients were involved. The corpus chronic gastritis (72%: 36/50 vs. 56.4%: 427/752), corpus atrophy (42.0%: 21/50 vs. 18.2%: 137/752) and intestinal metaplasia (IM) (64.0%: 32/50 vs. 21.5%: 162/752) were significantly higher in gastric cancer than non-cancer patients, respectively. Therefore, corpus chronic gastritis, corpus atrophy and IM were considered as high risk disease. The best serum marker to predict the high risk status was PGI/II < 3.1 (sensitivity 67.2%, specificity 61%) and PGI/II further reduced to < 2.2 (sensitivity 66%, specificity 65.1%) together with PGI < 28 ng/mL (sensitivity 70%, specificity 70%) were the best prediction for gastric cancer. The best cut-off point to diagnose H. pylori infection was anti-H. pylori IgG > 8 U/mL. Multivariate analysis showed that anti-H. pylori IgG > 8 U/mL and PGI/II < 3.1 increased risk for high risk status and PGI/II < 3.1 remained to increase risk for gastric cancer.

CONCLUSION

The serum diagnosis using PGI/II < 3.1 cut-off value is valuable marker to predict high risk patients for population based massive screening.

Gastroesophageal reflux disease in an area with low Helicobacter pylori infection prevalence

The association between gastroesophageal reflux disease (GERD) prevalence and its risk factors in an area with low Helicobacter pylori prevalence is important to clarify. We analyzed the prevalence of GERD and risk factors in an area of Indonesia with low prevalence of H. pylori infection. We recruited 104 dyspeptic patients who underwent endoscopy in Surabaya. Patients were diagnosed with GERD based on the Los Angeles classification. We evaluated gastric biopsy specimens and measured serum pepsinogen levels. Interleukin polymorphisms were evaluated by polymerase chain reaction-restriction fragment length polymorphism. Of 104 patients, 56 (53.8%) were endoscopically found to have GERD, with most categorized as grade A; 48 (46.2%) were classified as non-GERD. Higher economic status, smoking, and a history of proton-pump inhibitor use significantly increased the risk of GERD. GERD Questionnaire scores showed a positive correlation with GERD (P < 0.001). An association was found between antral atrophic gastritis and GERD (P = 0.030), and patients with GERD more frequently had severe antral atrophy than nonerosive reflux disease (P = 0.018). We found an association between pepsinogen I/II levels and GERD (P = 0.047), but with low accuracy. IL-1β -511 TT and CT were predominant among the IL-1β -511 genotypes, and IL-8-251 AT and TT were predominant among the IL-8-251 genotypes. In conclusion, we found a high prevalence of GERD in an area with low prevalence of H. pylori infection, which could be associated with acid reflux. Smoking, history of proton-pump inhibitor use, and higher economic group significantly increased the risk of GERD.

Prevalence, Pathogenesis, Diagnosis, and Management of Microscopic Colitis

Microscopic colitis (MC), which is comprised of lymphocytic colitis and collagenous colitis, is a clinicopathological diagnosis that is commonly encountered in clinical practice during the evaluation and management of chronic diarrhea. With an incidence approaching the incidence of inflammatory bowel disease, physician awareness is necessary, as diagnostic delays result in a poor quality of life and increased health care costs. The physician faces multiple challenges in the diagnosis and management of MC, as these patients frequently relapse after successful treatment. This review article outlines the risk factors associated with MC, the clinical presentation, diagnosis and histologic findings, as well as a proposed treatment algorithm. Prospective studies are required to better understand the natural history and to develop validated histologic endpoints that may be used as end points in future clinical trials and serve to guide patient management.

Rate of missed oesophageal cancer at routine endoscopy and survival outcomes: A multicentric cohort study

Background

Missed oesophageal cancer (MEC) at upper gastrointestinal endoscopy (UGE) is poorly documented.

Objective

The objectives of this study were: (1) to assess the rate, predictors and survival of MEC; (2) to compare MEC and non-MEC tumours.

Methods

This was a retrospective cohort study conducted at four tertiary centres. Oesophageal cancers (ECs) diagnosed between 2008 and 2015 were included. Patients with a premalignant condition (Barrett, achalasia), prior diagnosis of EC or oesophagogastric junction tumour of gastric origin were excluded. MEC was defined as EC detected within 36 months after negative UGE.

Results

123,395 UGEs were performed during the study period, with 502 ECs being diagnosed (0.4%). A total of 391 ECs were finally included. Overall MEC rate was 6.4% (95% confidence intervals (CI): 4.4-9.3%). The interval between negative and diagnostic UGE was less than 2 years in 84% of the cases. Multivariate analysis showed that a negative endoscopy was associated with proton pump inhibitor (PPI) therapy and less experienced endoscopists. MEC was smaller than non-MEC at diagnosis (25 versus 40 mm, p = 0.021), more often flat or depressed (p = 0.013) and less frequently diagnosed as metastatic disease (p = 0.013). Overall 2-year survival rate was similar for MEC (20%) and non-MEC (24.1%) (p = 0.95).

Conclusions

MEC accounted for 6.4% of all ECs and was associated with poor survival. High-quality UGE and awareness of MEC may help to reduce its incidence.

Effect of Helicobacter pylori eradication on the regression of gastric polyps in National Cancer Screening Program

BACKGROUND/AIMS

Western guidelines recommend Helicobacter pylori eradication in H. pylori-associated gastric polyps; however, there is no standard guideline in Korea. The aim of this study is to assess the effect of H. pylori eradication on the regression of gastric hyperplastic polyps in National Cancer Screening Cohort, representative of general population.

METHODS

Among participants in National Cancer Screening Program, subjects who had H. pylori positive gastric hyperplastic polyps less than 10 mm and underwent follow-up endoscopy and H. pylori testing were enrolled. The effect of H. pylori eradication on hyperplastic gastric polyps was estimated using odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

A total of 183 H. pylori infected subjects with hyperplastic polyp at baseline underwent follow-up endoscopy and H. pylori test after mean of 2.2 years. Successful H. pylori eradication markedly induced the disappearance of hyperplastic polyps comparing to non-eradication group (83.7% vs. 34.1%, p = 0.001). Successful eradication increased the possibility of disappearance of hyperplastic polyps (adjusted OR, 5.56; 95% CI, 2.63 to 11.11). Polyp size was inversely related with the disappearance of hyperplastic polyps (adjusted OR, 59; 95% CI, 0.48 to 0.71).

CONCLUSIONS

Eradication of H. pylori infection may induce disappearance of gastric hyperplastic polyps in National Cancer Screening Cohort.

Metastatic Renal Cell Carcinoma as Solitary Subcentimeter Polypoid Gastric Mucosal Lesions: Clinicopathologic Analysis of Five Cases

Background

The stomach is an uncommon site for metastatic carcinoma. Approximately 6% of renal cell carcinomas (RCCs) may metastasize to the stomach. The majority of the reported metastatic RCCs in the stomach presented as large masses or ulcers greater than a centimeter in size. It is very rare to encounter metastatic RCC as a solitary small polypoid gastric mucosal lesion.

Methods

In this study, we collected surgical pathology cases of gastric metastasis from RCC that measured 1.0 cm or less at the time of endoscopy. The clinicopathological characteristics were analyzed.

Results

Five patients with subcentimeter metastatic RCC involving the gastric mucosa were identified. The clinical presentation for upper endoscopic examination was non-specific. Two of the five patients did not have a known history of RCC. In the three patients with a previous history of RCC, the interval from primary RCC diagnosis to the detection of gastric mucosal metastasis was 5, 6, and 10 years, respectively. Endoscopically, all the lesions were solitary, ranging in size from 0.4 to 1 cm. Histologically, all five cases were of the clear cell type consisting of a bland clear cell proliferation within the lamina propria. Although the tumor cells were relatively bland, the presence of clear cytoplasm, nuclear membrane irregularity, occasional enlarged hyperchromatic atypical nuclei, and destructive growth in the center of the lesion should promote immunohistochemical workup. Immunohistochemically, the RCC cells exhibited at least patchy immunoreactivity for cytokeratin and RCC markers. In two cases, there were many CD68 positive foamy histiocytes intermingled with the tumor cells.

Conclusion

Metastatic RCC can rarely present as subcentimeter polypoid gastric mucosal lesions. The remote or unknown history of RCC, the non-specific endoscopic appearance, and the bland histological features may lead to a potential diagnostic pitfall. It is of importance to raise the awareness of such an unusual presentation of metastatic RCC in the stomach and to include metastatic RCC in the differential diagnosis for gastric mucosal polyps with clear cell morphology.

Preliminary opinion on assessment categories of stomach ultrasound report and data system (Su-RADS)

OBJECTIVE

Transabdominal ultrasound after oral administration of an echoic cellulose-based gastric ultrasound contrast agent (TUS-OCCA) has recently been suggested as a valuable mass-screening tool for gastric cancer. The aim of this study was to propose a producible stomach ultrasound reporting and data system (Su-RADS) using TUS-OCCA for gastric cancer screening.

PATIENTS

The study includes information of 2738 patients who underwent both gastroscopy and TUS-OCCA examinations recorded in software system. Gastroscopy examination with pathological diagnosis was considered as gold standard. Various gastric lesions were classified into category 1-5 based on gastric wall thicknesses of them (especially the mucosa layer).

RESULTS

The total malignant ratios of patients enrolled in this study were 17.1% (469/2738). The malignant ratios for category 1-5 were, respectively, 1.1, 1.7, 12.2, 34.2 and 78.1%. Category 2 indicated mild thickening of gastric wall at low risk for malignancy (1.7%); category 3 indicated moderate thickening at moderate risk for malignancy (12.2%); category 4 indicated severe thickening at high risk for malignancy (34.2%); category 5 indicated extremely severe thickening at extremely high risk for malignancy (78.1%). If category 2 was identified as cut-off point distinguishing between benign and malignant, the sensitivity and specificity by Su-RADS are 95.1 and 78.6%, respectively.

CONCLUSION

The Su-RADS system could inform the physicians about key findings, indicating the risk for malignancy and necessity of additional gastroscopy examination. Prospectively randomly controlled study design with larger clinical trial is needed for further investigations.

[Gastric adenocarcinoma arising in giant hyperplastic polyp]

Gastric hyperplastic polyps are usually solitary, their development is supposed to be associated with excessive proliferation of foveolar cells. It is essential to differentiate hyperplastic polyps from other sporadic polyps (adenomatous and fundic gland polyps) and lesions, included in familial polyposis syndromes. The frequency of adenocarcinoma in large gastric hyperplastic polyps (more than 1-2 cm in size) is about 2,1%. This article includes case report of gastric adenocarcinoma arised in large hyperplastic polyp in a 56-year-old patient. On histological examination a well-differentiated adenocarcinoma without invasion in the peduncle was identified. Immunohistochemically cells of adenocarcinoma showed elevated expression of claudin-3, CDX2, p53 and Ki67 compared to hyperplastic glands and dysplastic areas of the polyp. Also focal expression of MUC2 was revealed in adenocarcinoma. Expression of MUC5AC, CD44 and cyclin D1 was less prominent in cancer areas compared to hyperplastic and dysplastic glands. Levels of expression of claudin-1, claudin-4 and β-catenin were equal in adenocarcinoma and hyperplastic structures. Control endoscopic examination with following morphologic examination was performed three months after surgical operation. No signs of tumor growth were identified.

Acute graft-versus-host disease of the gut: considerations for the gastroenterologist

Haematopoietic stem cell transplantation (HSCT) is central to the management of many haematological disorders. A frequent complication of HSCT is acute graft-versus-host disease (GVHD), a condition in which immune cells from the donor attack healthy recipient tissues. The gastrointestinal system is among the most common sites affected by acute GVHD, and severe manifestations of acute GVHD of the gut portends a poor prognosis in patients after HSCT. Acute GVHD of the gastrointestinal tract presents both diagnostic and therapeutic challenges. Although the clinical manifestations are nonspecific and overlap with those of infection and drug toxicity, diagnosis is ultimately based on clinical criteria. As reliable serum biomarkers have not yet been validated outside of clinical trials, endoscopic and histopathological evaluation continue to be utilized in diagnosis. Once a diagnosis of gastrointestinal acute GVHD is established, therapy with systemic corticosteroids is typically initiated, and non-responders can be treated with a wide range of second-line therapies. In addition to treating the underlying disease, the management of complications including profuse diarrhoea, severe malnutrition and gastrointestinal bleeding is paramount. In this Review, we discuss strategies for the diagnosis and management of acute GVHD of the gastrointestinal tract as they pertain to the practising gastroenterologist.

Evaluation and management of gastric epithelial polyps

Gastric polyps include a wide spectrum of lesions with different histology and neoplastic potential. They are found in up to 6% of upper gastrointestinal endoscopy and are usually asymptomatic and incidentally diagnosed, being in the vast majority epithelial gastric polyps. Hyperplastic, fundic gland and adenomas are the most common types of gastric polyps and, although each type may have typical endoscopic appearances, they all must be sampled at the initial endoscopy for histological assessment. Also, the normal appearing gastric mucosa should be sampled to stage atrophic changes, rule out endoscopically non-visible dysplasia and to diagnose Helicobacter pylori. Polyposis syndromes that affect the stomach are rare but should be taken into account. Hamartomatous polyps can be found in Juvenile polyposis, Cowden syndrome and Peutz-Jeghers syndrome. On the other hand, multiple fundic gland polyps are present in the majority of patients with familial adenomatous polyposis. In this study we provide a comprehensive review on the evaluation and management of gastric epithelial polyps, in this way helping physicians to properly handle this type of lesions.

Evaluation of Transabdominal Ultrasound with Oral Cellulose-Based Contrast Agent in the Detection and Surveillance of Gastric Ulcer

The aim of this study was to assess the role of transabdominal ultrasound with cellulose-based oral contrast agent (TUS-OCCA) in the detection and surveillance of gastric ulcer. The study was approved by the institutional review board at Shengjing Hospital of China Medical University. A total of 124 consecutive patients with benign gastric ulcer diagnosed by gastroscopy and biopsy were enrolled. Serial TUS-OCCA (approximately 1 exam every 2 wk) was performed to monitor the effects of treatment, and additional interventions were planned according to the results. TUS-OCCA detected gastric ulcer in 76% of patients (94 of 124). The detection rates for lesions of ≤5 mm, lesions of 5-10 mm, lesions of 10-15 mm and lesions >15 mm were 32% (10 of 31), 77% (27 of 35), 96% (25 of 26) and 100% (32 of 32), respectively. The detection rates for lesions located in the antrum, angle and body were 70%, 84% and 85%, respectively. Among 30 undetected lesions, which ranged 2-13 mm in size, 11 were at the antrum, 9 at the angle, 3 in the body, 6 at the cardia and 1 at the fundus. During the follow-up period, patients underwent a mean of 3.8 TUS-OCCA examinations (range 2-7), and ulcers were healed after 8 wk (range 2-12 wk) of standard therapy in 76 patients. Eighteen patients who did not show improvement after standard therapy underwent repeat gastroscopy with biopsy. Repeat biopsy was positive for gastric cancer in 4 of these: 2 of the remaining 14 were diagnosed with gastric cancer at gastrectomy, and 12 were diagnosed with chronic benign ulcer. These results indicate that serial TUS-OCCA can be used for close monitoring during routine treatment of gastric ulcers that are detectable by TUS-OCCA and that monitoring by TUS-OCCA can guide additional interventions. A non-invasive follow-up program based on TUS-OCCA can also help to detect gastric cancers that have been misdiagnosed as benign ulcers at the initial endoscopic biopsy.

Adherence to Celiac Disease and Eosinophilic Esophagitis Biopsy Guidelines Is Poor in Children

OBJECTIVES

Celiac disease (CD) and eosinophilic esophagitis (EoE) are underdiagnosed gastrointestinal conditions, which adversely affect children's health. Previous studies have shown that diagnostic guidelines for CD are not consistently followed in adults. The aims of the present study are to assess the frequency with which endoscopists comply with diagnostic guidelines for CD and EoE in children, and to determine whether an association exists between adherence to biopsy guidelines and disease detection in pediatric patients.

METHODS

We reviewed pathology reports from 9171 children (ages 0-18) with at least 1 duodenal biopsy, and 8280 children with at least 1 esophageal biopsy, with specimens submitted to a national pathology laboratory. Frequency of adherence to diagnostic guidelines and recommendations for CD and EoE were determined, and the effect of this upon detection of CD and EoE.

RESULTS

Overall, 35% of cases were biopsied according to the 2006 American Gastroenterological Association guidelines for CD diagnosis; 8% were biopsied according to the 2007 American Gastroenterological Association EoE consensus recommendations. Detection of CD and EoE increased with the number of biopsies collected (P for trend in each <0.001). Adherence to diagnostic guidelines was particularly poor among those found to have histologically normal mucosa in both cohorts. The likelihood of CD and EoE diagnosis was significantly associated with adherence to diagnostic guidelines (odds ratio for CD 6.3, 95% confidence interval 4.4-8.9; odds ratio for EoE 2.4, 95% confidence interval 1.9-2.9).

CONCLUSION

Adherence to established guidelines is poor, and improved guideline adherence is associated with greater disease detection rates for CD and EoE.