Meta-analysis: The diagnostic efficacy of chromoendoscopy for early gastric cancer and premalignant gastric lesions

Acute compartment syndrome due to skeletal muscle metastases from poorly differentiated upper gastrointestinal adenocarcinoma: a case report

BACKGROUND

Acute compartment syndrome (ACS) is characterized by increased pressure within the fascial network of any muscle, leading to impaired circulation and potential myonecrosis. Very rarely, soft tissue infiltration by metastatic disease can cause localized swelling that increases intercompartmental pressures. We report an unusual case of invasive, poorly differentiated upper gastrointestinal adenocarcinoma presented by acute compartment syndrome of the lower extremity and subsequent acute kidney injury (AKI) caused by myonecrosis-induced cast nephropathy.

CASE PRESENTATION

A 52-year-old male presented to the hospital with rapid onset unilateral right leg pain and tense edema accompanied by myonecrosis with no explicable etiology complicated by AKI. Surgical fasciotomy and subsequent muscle biopsy yielded poorly differentiated non-small cell adenocarcinoma. CT imaging identified diffuse adenopathy along with abnormal thickening of the distal esophagus, gastroesophageal (GE) junction, and gastric cardia. Further investigation via upper esophagogastroduodenoscopy (EGD) revealed an exophytic mass in the distal esophagus extending into the stomach. This lesion was confirmed via biopsy as primary invasive poorly differentiated upper gastrointestinal (UGI) adenocarcinoma.

CONCLUSION

This case highlights the need for clinicians to implement high-risk screening for UGI cancers and consider skeletal muscle metastasis as a cause of nontraumatic ACS. It emphasizes the importance of interdisciplinary collaboration in managing such complex cases and the role of timely surgical and oncological intervention in preventing long-term complications of ACS. Furthermore, it highlights the potential use of more efficient and specific MR imaging techniques to diagnose ambiguous cases of ACS.

Endoscopic detection and diagnostic strategies for minute gastric cancer: A real-world observational study

BACKGROUND

Minute gastric cancers (MGCs) have a favorable prognosis, but they are too small to be detected by endoscopy, with a maximum diameter ≤ 5 mm.

AIM

To explore endoscopic detection and diagnostic strategies for MGCs.

METHODS

This was a real-world observational study. The endoscopic and clinicopathological parameters of 191 MGCs between January 2015 and December 2022 were retrospectively analyzed. Endoscopic discoverable opportunity and typical neoplastic features were emphatically reviewed.

RESULTS

All MGCs in our study were of a single pathological type, 97.38% (186/191) of which were differentiated-type tumors. White light endoscopy (WLE) detected 84.29% (161/191) of MGCs, and the most common morphology of MGCs found by WLE was protruding. Narrow-band imaging (NBI) secondary observation detected 14.14% (27/191) of MGCs, and the most common morphology of MGCs found by NBI was flat. Another three MGCs were detected by indigo carmine third observation. If a well-demarcated border lesion exhibited a typical neoplastic color, such as yellowish-red or whitish under WLE and brownish under NBI, MGCs should be diagnosed. The proportion with high diagnostic confidence by magnifying endoscopy with NBI (ME-NBI) was significantly higher than the proportion with low diagnostic confidence and the only visible groups (94.19% > 56.92% > 32.50%, P < 0.001).

CONCLUSION

WLE combined with NBI and indigo carmine are helpful for detection of MGCs. A clear demarcation line combined with a typical neoplastic color using nonmagnifying observation is sufficient for diagnosis of MGCs. ME-NBI improves the endoscopic diagnostic confidence of MGCs.

Diagnostic performance of deep-learning-based virtual chromoendoscopy in gastric neoplasms

BACKGROUNDS

Cycle-consistent generative adversarial network (CycleGAN) is a deep neural network model that performs image-to-image translations. We generated virtual indigo carmine (IC) chromoendoscopy images of gastric neoplasms using CycleGAN and compared their diagnostic performance with that of white light endoscopy (WLE).

METHODS

WLE and IC images of 176 patients with gastric neoplasms who underwent endoscopic resection were obtained. We used 1,633 images (911 WLE and 722 IC) of 146 cases in the training dataset to develop virtual IC images using CycleGAN. The remaining 30 WLE images were translated into 30 virtual IC images using the trained CycleGAN and used for validation. The lesion borders were evaluated by 118 endoscopists from 22 institutions using the 60 paired virtual IC and WLE images. The lesion area concordance rate and successful whole-lesion diagnosis were compared.

RESULTS

The lesion area concordance rate based on the pathological diagnosis in virtual IC was lower than in WLE (44.1% vs. 48.5%, p < 0.01). The successful whole-lesion diagnosis was higher in the virtual IC than in WLE images; however, the difference was insignificant (28.2% vs. 26.4%, p = 0.11). Conversely, subgroup analyses revealed a significantly higher diagnosis in virtual IC than in WLE for depressed morphology (41.9% vs. 36.9%, p = 0.02), differentiated histology (27.6% vs. 24.8%, p = 0.02), smaller lesion size (42.3% vs. 38.3%, p = 0.01), and assessed by expert endoscopists (27.3% vs. 23.6%, p = 0.03).

CONCLUSIONS

The diagnostic ability of virtual IC was higher for some lesions, but not completely superior to that of WLE. Adjustments are required to improve the imaging system's performance.

Investigating the role of circulating tumor cells in gastric cancer: a comprehensive systematic review and meta-analysis

Investigating the role of circulating tumor cells (CTCs) and their characteristics is still controversial in patients with gastric cancer (GC). Therefore, in this study, to provide a comprehensive review and meta-analyses of the literature on association of CTCs with gastric cancer, Scopus, Web of Science, Embase, and Medline were searched for systematic reviews and meta-analyses conducted during February 2022 using the keywords. Risk of bias, hazard ratios (HRs), and risk differences (RD) were assessed. Forty-five studies containing 3,342 GC patients from nine countries were assessed. The overall prevalence of CTC in GC was 69.37% (60.27, 77.78). The pooled result showed that increased mortality in GC patients was significantly associated with positive CTCs, poor overall survival (HR = 2.73, 95%CI 2.34-3.24, p < 0.001), and progression-free survival rate (HR = 2.78, 95%CI 2.01-3.85, p < 0.001). Subgroup analyses regarding markers, detection methods, treatment type, presence of distance metastasis, presence of lymph node metastasis, and overall risk of bias showed significant associations between the groups in terms of the incidence rates of CTCs, OS, and PFS. In addition, the results of risk differences based on sampling time showed that the use of the cell search method (RD: - 0.19, 95%CI (- 0.28, - 0.10), p < 0.001), epithelial marker (RD: - 0.12, 95%CI (- 0.25, 0.00), p 0.05) and mesenchymal markers (RD: - 0.35, 95%CI (- 0.57, - 0.13), p 0.002) before the treatment might have a higher diagnostic power to identify CTCs and also chemotherapy treatment (RD: - 0.17, 95%CI (- 0.31, - 0.03), p 0.016) could significantly reduce the number of CTCs after the treatment. We also found that the risk differences between the clinical early and advanced stages were not statistically significant (RD: - 0.10, 95%CI (- 0.23, 0.02), P 0.105). Also, in the Lauren classification, the incidence of CTC in the diffuse type (RD: - 0.19, 95%CI (- 0.37, - 0.01), P0.045) was higher than that in the intestinal type. Meta-regression analysis showed that baseline characteristics were not associated with the detection of CTCs in GC patients. According to our systematic review and meta-analysis, CTCs identification may be suggested as a diagnostic technique for gastric cancer screening, and the outcomes of CTC detection may also be utilized in the future to create personalized medicine programs.

Umbrella systematic review of potential quality indicators for the detection of dysplasia and cancer at upper gastrointestinal endoscopy

Background and study aims Upper gastrointestinal (UGI) endoscopy lacks established quality indicators. We conducted an umbrella systematic review of potential quality indicators for the detection of UGI cancer and dysplasia. Methods Bibliographic databases were searched up to December 2021 for systematic reviews and primary studies. Studies reporting diagnostic accuracy, detection rates or the association of endoscopy or endoscopist-related factors with UGI cancer or dysplasia detection were included. AMSTAR2 and JBI checklists were used to assess systematic review and primary study quality. Clinical heterogeneity precluded meta-analysis and findings are summarized narratively. Results Eight systematic reviews and nine primary studies were included. Image enhancement, especially narrow band imaging, had high diagnostic accuracy for dysplasia and early gastric cancer (pooled sensitivity 0.87 (95% CI 0.84-0.89) and specificity 0.97 (0.97-0.98)). Higher detection rates with longer endoscopy examination times were reported in three studies, but no difference was observed in one study. Endoscopist biopsy rate was associated with increased gastric cancer detection (odds ratio 2.5; 95% confidence interval [CI] 2.1-2.9). Early esophageal cancer (0.17% vs 0.14%, P =0.04) and gastric cancer (0.16% vs 0.12%, P =0.02) detection rates were higher with propofol sedation compared to no sedation. Endoscopies performed by trained endoscopists on dedicated Barrett's surveillance lists had higher detection rates (8% vs 3%, P <0.001). The neoplasia detection rate during diagnostic endoscopies for Barrett's esophagus was 7% (95% CI 4%-10%). Conclusions Image enhancement use, longer examination times, biopsy rate and propofol sedation are potential quality indicators for UGI endoscopy. Neoplasia detection rate and dedicated endoscopy lists are additional potential quality indicators for Barrett's esophagus.

Gastric Intestinal Metaplasia: Challenges and the Opportunity for Precision Prevention

GIM is a persistent, premalignant lesion whereby gastric mucosa is replaced by metaplastic mucosa resembling intestinal tissue, arising in the setting of chronic inflammation, particularly in the context of Helicobacter pylori. While the overall rates of progression to gastric adenocarcinoma are low, estimated at from 0.25 to 2.5%, there are features that confer a much higher risk and warrant follow-up. In this review, we collate and summarise the current knowledge regarding the pathogenesis of GIM, and the clinical, endoscopic and histologic risk factors for cancer. We examine the current state-of-practice with regard to the diagnosis and management of GIM, which varies widely in the published guidelines and in practice. We consider the emerging evidence in population studies, artificial intelligence and molecular markers, which will guide future models of care. The ultimate goal is to increase the detection of early gastric dysplasia/neoplasia that can be cured while avoiding unnecessary surveillance in very low-risk individuals.

Histopathological Evaluation of Gastric Mucosal Atrophy for Predicting Gastric Cancer Risk: Problems and Solutions

Patients suffering from chronic gastritis and developing gastric mucosa atrophy are at increased risk of the development of gastric cancer. The diagnosis of chronic atrophic gastritis (CAG) is a complex procedure involving a detailed history taking, a thorough physical examination and the use of laboratory and instrumental diagnostic methods among which the endoscopy of the upper digestive tract is the cornerstone because it allows the assessment of the topography of gastritis and identification of erosions and areas of intestinal metaplasia with the use of NBI endoscopy. However, the diagnosis of CAG requires morphological examination of the gastric mucosa. So, in addition to assessing macroscopic changes in the gastric mucosa, it is necessary to take biopsy specimens in accordance with the protocols for their morphological and immunohistochemical examination. In the absence of specific diagnostic stigmas of CAG, close cooperation between a clinician, endoscopist and pathologist is necessary. The article presents systematized data on the histopathological assessment of the gastric mucosa atrophy to predict the risk of gastric cancer.

Toward next-generation endoscopes integrating biomimetic video systems, nonlinear optical microscopy, and deep learning

According to the World Health Organization, the proportion of the world's population over 60 years will approximately double by 2050. This progressive increase in the elderly population will lead to a dramatic growth of age-related diseases, resulting in tremendous pressure on the sustainability of healthcare systems globally. In this context, finding more efficient ways to address cancers, a set of diseases whose incidence is correlated with age, is of utmost importance. Prevention of cancers to decrease morbidity relies on the identification of precursor lesions before the onset of the disease, or at least diagnosis at an early stage. In this article, after briefly discussing some of the most prominent endoscopic approaches for gastric cancer diagnostics, we review relevant progress in three emerging technologies that have significant potential to play pivotal roles in next-generation endoscopy systems: biomimetic vision (with special focus on compound eye cameras), non-linear optical microscopies, and Deep Learning. Such systems are urgently needed to enhance the three major steps required for the successful diagnostics of gastrointestinal cancers: detection, characterization, and confirmation of suspicious lesions. In the final part, we discuss challenges that lie en route to translating these technologies to next-generation endoscopes that could enhance gastrointestinal imaging, and depict a possible configuration of a system capable of (i) biomimetic endoscopic vision enabling easier detection of lesions, (ii) label-free in vivo tissue characterization, and (iii) intelligently automated gastrointestinal cancer diagnostic.

Advanced Imaging in Gastrointestinal Endoscopy: A Literature Review of the Current State of the Art

BACKGROUND AND AIMS

Gastrointestinal (GI) endoscopy has known a great evolution in the last decades. Imaging techniques evolved from imaging with only standard white light endoscopes toward high-definition resolution endoscopes and the use of multiple color enhancement techniques, over to automated endoscopic assessment systems based on artificial intelligence. This narrative literature review aimed to provide a detailed overview on the latest evolutions within the field of advanced GI endoscopy, mainly focusing on the screening, diagnosis, and surveillance of common upper and lower GI pathology.

METHODS

This review comprises only literature about screening, diagnosis, and surveillance strategies using advanced endoscopic imaging techniques published in (inter)national peer-reviewed journals and written in English. Studies with only adult patients included were selected. A search was performed using MESH terms: dye-based chromoendoscopy, virtual chromoendoscopy, video enhancement technique, upper GI tract, lower GI tract, Barrett's esophagus, esophageal squamous cell carcinoma, gastric cancer, colorectal polyps, inflammatory bowel disease, artificial intelligence. This review does not elaborate on the therapeutic application or impact of advanced GI endoscopy.

CONCLUSIONS

Focusing on current and future applications and evolutions in the field of both upper and lower GI advanced endoscopy, this overview is a practical but detailed projection of the latest developments. Within this review, an active leap toward artificial intelligence and its recent developments in GI endoscopy was made. Additionally, the literature is weighted against the current international guidelines and assessed for its potential positive future impact.

Image-enhanced endoscopy in the diagnosis of gastric premalignant conditions and gastric cancer

Diagnosis of early gastric cancer and its precancerous lesions remains a challenge for great part of western endoscopists. Changes seen in the mucosal pattern are generally subtle and hence difficult to identify. In this article, we will review the usefulness of conventional and virtual chromoendoscopy and magnification endoscopy in the recognition and classification of these lesions.

Endoscopic Imaging for the Diagnosis of Neoplastic and Pre-Neoplastic Conditions of the Stomach

Gastric cancer is an aggressive disease with low long-term survival rates. An early diagnosis is essential to offer a better prognosis and curative treatment. Upper gastrointestinal endoscopy is the main tool for the screening and diagnosis of patients with gastric pre-neoplastic conditions and early lesions. Image-enhanced techniques such as conventional chromoendoscopy, virtual chromoendoscopy, magnifying imaging, and artificial intelligence improve the diagnosis and the characterization of early neoplastic lesions. In this review, we provide a summary of the currently available recommendations for the screening, surveillance, and diagnosis of gastric cancer, focusing on novel endoscopy imaging technologies.

Endoscopic advances in the management of gastric cancer and premalignant gastric conditions

Gastric cancer is the fifth most common cancer and in 2018, it was the third most common cause of cancer-related deaths worldwide. Endoscopic advances continue to be made for the diagnosis and management of both early gastric cancer and premalignant gastric conditions. In this review, we discuss the epidemiology and risk factors of gastric cancer and emphasize the differences in early vs late-stage gastric cancer outcomes. We then discuss endoscopic advances in the diagnosis of early gastric cancer and premalignant gastric lesions. This includes the implementation of different imaging modalities such as narrow-band imaging, chromoendoscopy, confocal laser endomicroscopy, and other experimental techniques. We also discuss the use of endoscopic ultrasound in the diagnosis and staging of early gastric cancer. We then discuss the endoscopic advances made in the treatment of these conditions, including endoscopic mucosal resection, endoscopic submucosal dissection, and hybrid techniques such as laparoscopic endoscopic cooperative surgery. Finally, we comment on the current suggested recommendations for surveillance of both gastric cancer and its premalignant conditions.

Diagnostic value of artificial intelligence-assisted endoscopy for chronic atrophic gastritis: a systematic review and meta-analysis

Background and aims

The diagnosis of chronic atrophic gastritis (CAG) under normal white-light endoscopy depends on the endoscopist's experience and is not ideal. Artificial intelligence (AI) is increasingly used to diagnose diseases with good results. This review aimed to evaluate the accuracy of AI-assisted diagnosis of CAG through a meta-analysis.

Methods

We conducted a comprehensive literature search of four databases: PubMed, Embase, Web of Science, and the Cochrane Library. Studies published by November 21, 2022, on AI diagnosis CAG with endoscopic images or videos were included. We assessed the diagnostic performance of AI using meta-analysis, explored the sources of heterogeneity through subgroup analysis and meta-regression, and compared the accuracy of AI and endoscopists in diagnosing CAG.

Results

Eight studies that included a total of 25,216 patients of interest, 84,678 image training set images, and 10,937 test set images/videos were included. The results of the meta-analysis showed that the sensitivity of AI in identifying CAG was 94% (95% confidence interval [CI]: 0.88-0.97, I² = 96.2%), the specificity was 96% (95% CI: 0.88-0.98, I² = 98.04%), and the area under the summary receiver operating characteristic curve was 0.98 (95% CI: 0.96-0.99). The accuracy of AI in diagnosing CAG was significantly higher than that of endoscopists.

Conclusions

AI-assisted diagnosis of CAG in endoscopy has high accuracy and clinical diagnostic value.

Systematic review registration

http://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42023391853.

Chinese integrated guideline on the management of gastric precancerous conditions and lesions

The standardized diagnosis and management of gastric precancerous conditions and lesions are important to prevent gastric cancer. This guideline, created by 5 traditional Chinese medicine and Western medicine associations, based on the current morbidity and diagnosis and treatment of gastric precancerous conditions and lesions, provides specific key points and strategies for diagnosis and treatment in the following five aspects: definition and epidemiology, diagnosis and stage, surveillance, treatment and efficacy evaluation. It is hoped that these aspects, assessed by integrating Western medicine and traditional Chinese medicine and involving multidisciplinary participation, will play a guiding role in clinical diagnosis and treatment and achieve effective secondary prevention of gastric cancer.

Quality performance measures in upper gastrointestinal endoscopy for lesion detection: Italian AIGO-SIED-SIGE joint position statement

Esophagogastroduodenoscopy (EGD) plays a crucial role in the management of gastroduodenal diseases by allowing a direct and accurate evaluation of the mucosa and the execution of several operative maneuvers. Despite a constant development of new imaging tools and operative devices, the widespread use of EGD has not resulted in a significant reduction of mortality for patients affected by esophageal/gastric cancer during the last three decades in Western countries. Evidence indicates that this disheartening scenario derives from a high variability of execution of EGD which determines its quality and diagnostic yield, delaying the diagnosis of neoplastic diseases. Based on this evidence, in recent years many scientific societies have produced different position papers aimed at defining quality performance measures in EGD. Thus, the Italian Association of Gastroenterologists and Endoscopists, the Italian Society of Digestive Endoscopy and the Italian Society of Gastroenterology have produced this joint document based on the review of ASGE, ACG, BSG, ESGE and Asian Consensus EGD position papers with the aim of indicating the quality standards of EGD (pre-, intra- and post-procedure) focused on lesion detection to be adopted in the Italian context.

Pernicious Anemia: The Hematological Presentation of a Multifaceted Disorder Caused by Cobalamin Deficiency

Pernicious anemia is still a neglected disorder in many medical contexts and is underdiagnosed in many patients. Pernicious anemia is linked to but different from autoimmune gastritis. Pernicious anemia occurs in a later stage of autoimmune atrophic gastritis when gastric intrinsic factor deficiency and consequent vitamin B₁₂ deficiency may occur. The multifaceted nature of pernicious anemia is related to the important role of cobalamin, which, when deficient, may lead to several dysfunctions, and thus, the proteiform clinical presentations of pernicious anemia. Indeed, pernicious anemia may lead to potentially serious long-term complications related to micronutrient deficiencies and their consequences and the development of gastric cancer and type 1 gastric neuroendocrine tumors. When not recognized in a timely manner or when pernicious anemia is diagnosed with delay, these complications may be potentially life-threatening and sometimes irreversible. The current review aimed to focus on epidemiology, pathogenesis, and clinical presentations of pernicious anemia in an attempt to look beyond borders of medical specialties. It aimed to focus on micronutrient deficiencies besides the well-known vitamin B₁₂ deficiency, the diagnostic approach for pernicious anemia, its long-term complications and optimal clinical management, and endoscopic surveillance of patients with pernicious anemia.

Gastric intestinal metaplasia: Long-term follow-up results

Baackground

Precancerous lesions are the most commonly cited factor in gastric cancer etiology. The sequence of events in intestinal-type gastric carcinogenesis is considered to be chronic gastritis, atrophy, intestinal metaplasia (IM), dysplasia, and carcinoma, respectively. Early diagnosis and treatment of advanced precursor lesions and gastric cancer is possible by identifying and monitoring patients with such premalignant lesions.

Aim

In our study, we aimed to evaluate the long-term follow-up results of intestinal metaplasia in our hospital and the rate of progression to malignancy by comparing these patients with patients who have undergone gastroscopy without a diagnosis of intestinal metaplasia.

Material and Method

One hundred and fifty-six followed-up patients out of 700 between the ages of 18 and 85 who were admitted to our hospital between 2009 and 2019, who were diagnosed with IM by pathological examination from biopsy material, and 150 patients who were not diagnosed with IM between 2009 and 2011 were included. The results of the cases were evaluated first retrospectively; then, the patients who were invited for control and underwent endoscopy were evaluated prospectively. IM and control groups were compared in terms of dysplasia and gastric cancer development. In addition, the IM group was compared in terms of 5 and 10 years of follow-up, extensive or local involvement, and complete and incomplete involvement in terms of dysplasia and cancer development.

Results

The follow-up period of the patients ranged from 1 to 10 years, and the mean follow-up interval was 4.2 ± 2.8 (min: 1; max: 10) years. Age, gender, and pathology results of the patients were examined in terms of IM type, localization of IM, pathology accompanying IM, and presence of Helicobacter pylori (Hp) infection and compared with the control group. While gastric carcinoma was detected in three of 156 patients in the IM group, gastric carcinoma was not detected in the follow-up of 150 patients in the control group. IM was most common in the antrum. Incomplete IM was detected in 89 patients, and complete IM in 69 patients. While two of the three patients with gastric carcinoma were localized to the antrum, one patient had incomplete-type IM and two patients had complete-type IM, and Hp was positive in two patients. While dysplasia was detected in nine of the patients diagnosed with IM, it was detected in two patients in the control group. A statistically significant difference was found between the IM and control groups in terms of dysplasia positivity (p = 0.037). On the other hand, no statistically significant difference was found between the IM and control groups in terms of age-group, gender, follow-up time group, and Hp positivity (p > 0.05). There was no significant difference between those who were followed up for 5 and 10 years in the IM group in terms of dysplasia and cancer development.

Conclusion

Therefore, it is considered that patients with intestinal metaplasia may be followed up at longer intervals, except for patients with race, ethnicity, incomplete type, extensive involvement, and a family history of gastric cancer.

Identifying the pre-malignant stomach: from guidelines to practice

Gastric adenocarcinoma develops after stepwise progression from normal mucosa through to adenocarcinoma most commonly after being triggered by Helicobacter pylori (H. pylori) infection. As disease is often diagnosed late, the prognosis for gastric adenocarcinoma is poor. Identifying pre-malignant mucosal lesions such as atrophic gastritis, intestinal metaplasia and dysplasia is one strategy adopted by clinicians to reduce cancer related mortality. Surveillance of high-risk individuals and endoscopic resection of dysplastic lesions is recommended by international and UK guidelines. The early detection and endoscopic management reduce the need for invasive surgery. The advancement of image enhanced endoscopy technology, endoscopic training, risk stratification and histological assessment has proven pivotal to the management of pre-malignant lesions. In this review we outline the development of a high-risk stomach, endoscopic assessment and review practical guidelines on identifying pre-malignant gastric mucosa.

Clinical Recommendations of Russian Gastroenterological Association and RENDO Endoscopic Society on Diagnosis and Treatment of Gastritis and Duodenitis

Aim.The clinical guidelines are intended to supplement specialty decision-making for improved aid quality in patients with gastritis and duodenitis though acknowledging the latest clinical evidence and principles of evidencebased medicine.Key points.Gastritis is an inflammatory disease of stomach mucosa, with a separate definition of acute and chronic gastritis. Chronic gastritis is a cohort of chronic diseases uniting a typical morphology of persistent inflammatory infiltration, impaired cellular renewal with emergent intestinal metaplasia, atrophy and epithelial dysplasia of gastric mucosa. Oesophagogastroduodenoscopy (OGDS) or high-resolution OGDS with magnified or non-magnified virtual chromoendoscopy, including targeted biopsy for atrophy and intestinal metaplasia grading and neoplasia detection, are recommended to verify gastritis and duodenitis, precancer states and/or gastric mucosal changes. All chronic gastritis patients positive for H. рylori should undergo eradication therapy as aetiological and subsidiary for gastric cancer prevention. Chronic gastritis patients with symptoms of dyspepsia (epigastric pain, burning and congestion, early satiety), also combined with functional dyspepsia, are recommended proton pump inhibitors, prokinetics, rebamipide and bismuth tripotassium dicitrate in symptomatic treatment. With focal restricted intestinal metaplasia, follow-up is not required in most cases, mainly when advanced atrophic gastritis is ruled out in high-quality endoscopy with biopsy. However, a familial history of gastric cancer, incomplete intestinal metaplasia and persistent H. pylori infection render endoscopy monitoring with chromoendoscopy and targeted biopsy desirable once in three years. Patients with advanced atrophic gastritis should have high-quality endoscopy every 3 years, and once in 1–2 years if complicated with a familial history of gastric cancer.Conclusion.The recommendations condense current knowledge on the aetiology and pathogenesis of gastritis and duodenitis, as well as laboratory and instrumental diagnostic techniques, main approaches to aetiological H. pylori eradication and treatment of dyspeptic states.

Advances in optical gastrointestinal endoscopy: a technical review

Optical endoscopy is the primary diagnostic and therapeutic tool for management of gastrointestinal (GI) malignancies. Most GI neoplasms arise from precancerous lesions; thus, technical innovations to improve detection and diagnosis of precancerous lesions and early cancers play a pivotal role in improving outcomes. Over the last few decades, the field of GI endoscopy has witnessed enormous and focused efforts to develop and translate accurate, user-friendly, and minimally invasive optical imaging modalities. From a technical point of view, a wide range of novel optical techniques is now available to probe different aspects of light-tissue interaction at macroscopic and microscopic scales, complementing white light endoscopy. Most of these new modalities have been successfully validated and translated to routine clinical practice. Herein, we provide a technical review of the current status of existing and promising new optical endoscopic imaging technologies for GI cancer screening and surveillance. We summarize the underlying principles of light-tissue interaction, the imaging performance at different scales, and highlight what is known about clinical applicability and effectiveness. Furthermore, we discuss recent discovery and translation of novel molecular probes that have shown promise to augment endoscopists' ability to diagnose GI lesions with high specificity. We also review and discuss the role and potential clinical integration of artificial intelligence-based algorithms to provide decision support in real time. Finally, we provide perspectives on future technology development and its potential to transform endoscopic GI cancer detection and diagnosis.

A Diagnostic Method for Gastric Cancer Using Two-Photon Microscopy With Enzyme-Selective Fluorescent Probes: A Pilot Study

BACKGROUND

Endoscopy is the most important tool for gastric cancer diagnosis. However, it relies on naked-eye evaluation by endoscopists, and the histopathologic confirmation is time-consuming. We aimed to visualize and measure the activity of various enzymes through two-photon microscopy (TPM) using fluorescent probes and assess its diagnostic potential in gastric cancer.

METHODS

β-Galactosidase (β-gal), carboxylesterase (CES), and human NAD(P)H: quinone oxidoreductase (hNQO1) enzyme activities in the normal mucosa, ulcer, adenoma, and gastric cancer biopsy samples were measured using two-photon enzyme probes. The fluorescence emission ratio at long and short wavelengths (Ch2/Ch1) for each probe was comparatively analyzed. Approximately 8,000 - 9,000 sectional images in each group were obtained by measuring the Ch2/Ch1 ratio according to the tissue depth. Each probe was cross-validated by measuring enzymatic activity from a solution containing lysed tissue.

RESULTS

Total of 76 subjects were enrolled in this pilot study (normal 21, ulcer 18, adenoma 17, and cancer 20 patients, respectively). There were significant differences in the mean ratio values of β-gal (0.656 ± 0.142 vs. 1.127 ± 0.109, P < 0.001) and CES (0.876 ± 0.049 vs. 0.579 ± 0.089, P < 0.001) between the normal and cancer, respectively. The mean ratio value of cancer tissues was different compared to ulcer and adenoma (P < 0.001). The hNQO1 activity showed no significant difference between cancer and other conditions. Normal mucosa and cancer were visually and quantitatively distinguished through β-gal and CES analyses using TPM images, and enzymatic activity according to depth, was determined using sectional TPM ratiometric images. The results obtained from lysis buffer-treated tissue were consistent with TPM results.

CONCLUSIONS

TPM imaging using ratiometric fluorescent probes enabled the discrimination of gastric cancer from normal, ulcer, and adenoma. This novel method can help in a visual differentiation and provide quantitative depth profiling in gastric cancer diagnosis.

Endoscopic diagnosis and treatment of gastric dysplasia and early cancer: Current evidence and what the future may hold

Gastric cancer accounts for a significant proportion of worldwide cancer-related morbidity and mortality. The well documented precancerous cascade provides an opportunity for clinicians to detect and treat gastric cancers at an endoscopically curable stage. In high prevalence regions such as Japan and Korea, this has led to the implementation of population screening programs. However, guidelines remain ambiguous in lower prevalence regions. In recent years, there have been many advances in the endoscopic diagnosis and treatment of early gastric cancer and precancerous lesions. More advanced endoscopic imaging has led to improved detection and characterization of gastric lesions as well as superior accuracy for delineation of margins prior to resection. In addition, promising early data on artificial intelligence in gastroscopy suggests a future role for this technology in maximizing the yield of advanced endoscopic imaging. Data on endoscopic resection (ER) are particularly robust in Japan and Korea, with high rates of curative ER and markedly reduced procedural morbidity. However, there is a shortage of data in other regions to support the applicability of protocols from these high prevalence countries. Future advances in endoscopic therapeutics will likely lead to further expansion of the current indications for ER, as both technology and proceduralist expertise continue to grow.

Endoscopic Advances for Gastric Neoplasia Detection

This article explores advances in endoscopic neoplasia detection with supporting clinical evidence and future aims. The ability to detect early gastric neoplastic lesions amenable to curative endoscopic submucosal dissection provides the opportunity to decrease gastric cancer mortality rates. Newer imaging techniques offer enhanced views of mucosal and microvascular structures and show promise in differentiating benign from malignant lesions and improving targeted biopsies. Conventional chromoendoscopy is well studied and validated. Narrow band imaging demonstrates superiority over magnified white light. Autofluorescence imaging, i-scan, flexible spectral imaging color enhancement, and bright image enhanced endoscopy show promise but insufficient evidence to change current clinical practice.

Markers of gastric intestinal metaplasia under digital chromoendoscopy: systematic review and meta-analysis

Diagnosis of gastric intestinal metaplasia (GIM) under digital chromoendoscopy presents various markers. The diagnostic yield of each marker has shown variable results. A systematic review and meta-analysis were performed to evaluate the following markers: light blue crest (LBC), marginal turbid band (MTB), groove type (GT), white opaque substance (WOS). Discussion of their joint diagnosis, reliability, assessment of local GIM severity and influencing factors was also provided. PubMed, EMBASE, Cochrane Library and Web of science were searched. The Meta-DiSc and Stata software were used to analyze the data. Fourteen studies were included with a total of 3081 lesions. There were 12 studies for LBC, six for GT, four for MTB and one for WOS, respectively. The pooled results showed that the diagnostic sensitivity and specificity of LBC were 0.79 [95% confidence interval (CI) 0.76-0.81] and 0.95 (95% CI 0.94-0.96). The sensitivity of GT and MTB were 0.49 (95% CI 0.43-0.54) and 0.47 (95% CI 0.40-0.53), and the specificity were 0.92 (95% CI 0.89-0.94) and 0.92 (95% CI 0.89-0.95). The area under the summary receiver operating characteristic curve was 0.9532, 0.7791 and 0.9553 for LBC, GT and MTB, respectively. LBC resulted the most classic marker. Proper combined diagnosis can improve the diagnostic efficiency. Reliability of these markers was acceptable. These markers can help endoscopic to assess the severity of local GIM. Besides intestinal metaplasia, many factors can potentially interfere with the diagnosis.

Beyond the Guidelines: The Grey Zones of the Management of Gastric Cancer. Consensus Statements from the Gastric Cancer Italian Network (GAIN)

BACKGROUND

Management of gastric and gastroesophageal junction (GEJ) adenocarcinoma remains challenging, because of the heterogeneity in tumor biology within the upper gastrointestinal tract. Daily clinical practice is full of grey areas regarding the complexity of diagnostic, staging, and therapeutic procedures. The aim of this paper is to provide a guide for clinicians facing challenging situations in routine practice, taking a multidisciplinary consensus approach based on available literature.

METHODS

The GAIN (GAstric cancer Italian Network) group was established with the aims of reviewing literature evidence, discussing key issues in prevention, diagnosis, and management of gastric and GEJ adenocarcinoma, and offering a summary of statements. A Delphi consensus method was used to obtain opinions from the expert panel of specialists.

RESULTS

Forty-nine clinical questions were identified in six areas of interest: role of multidisciplinary team; risk factors; diagnosis; management of early gastric cancer and multimodal approach to localized gastric cancer; treatment of elderly patients with locally advanced resectable disease; and treatment of locally advanced and metastatic cancer.

CONCLUSIONS

The statements presented may guide clinicians in practical management of this disease.

Gastric cancer- endoscopic treatment of early lesions, the West learns from the East

Gastric cancer still has one of the highest incidence rates worldwide. Screening programs have been established in high incidence regions, especially in Asia, but in the West, screening for gastric cancer is not generally recommended. Gastroscopy is the gold standard for diagnosing gastric cancer. For the treatment of early gastric cancer, endoscopic resection is the method of choice. With the ESD technique, larger lesions can be resected en-bloc. Guideline and extended guideline criteria for the choice of lesions for ESD have been evaluated extensively, initially in Asia and later in the West as well. For lesions which are out of indication, a surgical approach must be recommended. To detect early recurrence or metachronous lesions, follow-up should be performed after ER.

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.

Magnifying endoscopy in detecting early gastric cancer: A network meta-analysis of prospective studies

BACKGROUND

Conventional white-light imaging endoscopy (C-WLI) had a significant number of misdiagnosis in early gastric cancer (EGC), and magnifying endoscopy (ME) combined with different optical imaging was more accurate in the diagnosis of EGC. This study aimed to evaluate the accuracy of ME and compare the accuracy of ME with different optical imaging in detecting EGC.

METHODS

A comprehensive literature search was conducted to identify all relevant studies. Pair-wise meta-analysis was conducted to evaluate the accuracy of ME, and Bayesian network meta-analysis was performed to combine direct and indirect evidence and estimate the relative effects.

RESULTS

Eight prospective studies were identified with a total of 5948 patients and 3 optical imaging in ME (ME with WLI (M-WLI), ME with narrow-band imaging (M-NBI), and ME with blue laser imaging (M-BLI)). Pair-wise meta-analysis showed a higher accuracy of ME than C-WLI (OR: 2.97, 95% CI: 1.68∼5.25). In network meta-analysis, both M-NBI and M-BLI were more accurate than M-WLI (OR: 2.56, 95% CI: 2.13∼3.13; OR: 3.13, 95% CI: 1.85∼5.71). There was no significant difference between M-NBI and M-BLI.

CONCLUSION

ME was effective in improving the detecting rate of EGC, especially with NBI or BLI.

Complementary and alternative therapies for precancerous lesions of gastric cancer: A protocol for a Bayesian network meta analysis

BACKGROUND

Gastric cancer is one of the most common malignant tumors, which seriously affect peoples quality of life and threaten people's health. Precancerous lesions of gastric cancer (PLGC) are a critical stage in the occurrence and development of gastric cancer. Early effective intervention is an important means to prevent and control gastric cancer. In this study, we will evaluate the efficacy and safety of complementary and alternative therapies in the treatment of PLGC by Bayesian network meta-analysis (NMA).

METHODS

We will search PubMed, Cochrane Library, CNKI and other databases to gather randomized controlled trials (RCTs) on the treatment of PLGC with complementary and alternative therapies. Two reviewers will screen the literature and extract the data according to the inclusion and exclusion criteria, and then assess the quality and bias risk according to Cochrane's Risk of Bias Assessment Tool. Bayesian network meta-analysis will be conducted by Stata16.0 and WinBUGS1.4.3.

RESULTS

This study will compare and rank the efficacy and safety of different complementary and alternative therapies for PLGC.

CONCLUSION

This study can provide reliable evidence for the efficacy and safety of complementary and alternative therapies in treatment of PLGC. We expect to provide scientific and rigorous evidence support for clinicians and patients, and then assist them to choose the optimum treatment.

PROTOCOL REGISTRATION NUMBER

INPLASY2020120077.

Gastric cancer prevention strategies: A global perspective

Gastric cancer (GC) is the fifth most common cancer worldwide, and mortality rates are still high. Primary preventive strategies, aimed to reduce risk factors and promote protective ones, will lead to a decrease in GC incidence. Helicobacter pylori infection is a well-established carcinogen for GC, and its eradication is recommended as the best strategy for the primary prevention. However, the role of other factors such as lifestyle, diet, and drug use is still under debate in GC carcinogenesis. Unfortunately, most patients with GC are diagnosed at late stages when treatment is often ineffective. Neoplastic transformation of the gastric mucosa is a multistep process, and appropriate diagnosis and management of preneoplastic conditions can reduce GC-related mortality. Several screening strategies in relation to GC incidence have been proposed in order to detect neoplastic lesions at early stages. The efficacy of screening strategies in reducing GC mortality needs to be confirmed. This review provides an overview of current international guidelines and recent literature on primary and secondary prevention strategies for GC.

A deep learning method for delineating early gastric cancer resection margin under chromoendoscopy and white light endoscopy

BACKGROUND

Accurate delineation of cancer margins is critical for endoscopic curative resection. This study aimed to train and validate real-time fully convolutional networks for delineating the resection margin of early gastric cancer (EGC) under indigo carmine chromoendoscopy (CE) or white light endoscopy (WLE), and evaluated its performance and that of magnifying endoscopy with narrow-band imaging (ME-NBI).

METHODS

We collected CE and WLE images of EGC lesions to train fully convolutional networks ENDOANGEL. ENDOANGEL was tested both on stationary images and endoscopic submucosal dissection (ESD) videos. The accuracy and reliability of ENDOANGEL and NBI-dependent delineation were further evaluated by a novel endoscopy-pathology point-to-point marking.

RESULTS

ENDOANGEL had an accuracy of 85.7% in the CE images and 88.9% in the WLE images under an overlap ratio threshold of 0.60 in comparison with the manual markers labeled by the experts. In the ESD videos, the resection margins predicted by ENDOANGEL covered all areas of high-grade intraepithelial neoplasia and cancers. The minimum distance between the margins predicted by ENDOANGEL and the histological cancer boundary was 3.44 ± 1.45 mm which outperformed the resection margin based on ME-NBI.

CONCLUSIONS

ENDOANGEL has the potential to assist endoscopists in delineating the resection extent of EGC under CE or WLE during ESD.

Helicobacter pylori-induced inflammation masks the underlying presence of low-grade dysplasia on gastric lesions

BACKGROUND

Helicobacter pylori (H. pylori) infection has been associated with a long-term risk of precancerous gastric conditions (PGC) even after H. pylori eradication.

AIM

To investigate the efficacy of High-Resolution White-Light Endoscopy with Narrow-Band Imaging in detecting PGC, before/after H. pylori eradication.

METHODS

We studied 85 consecutive patients with H. pylori-related gastritis with/without PGC before and 6 mo after proven H. pylori eradication. Kimura-Takemoto modified and endoscopic grading of gastric intestinal metaplasia classifications, were applied to assess the endoscopic extension of atrophy and intestinal metaplasia. The histological result was considered to be the gold standard. The Sydney System, the Operative-Link on Gastritis-Assessment, and the Operative-Link on Gastric-Intestinal Metaplasia were used for defining histological gastritis, atrophy and intestinal metaplasia, whereas dysplasia was graded according to World Health Organization classification. Serum anti-parietal cell antibody and anti-intrinsic factor were measured when autoimmune atrophic gastritis was suspected.

RESULTS

After H. pylori eradication histological signs of mononuclear/polymorphonuclear cell infiltration and Mucosal Associated Lymphoid Tissue-hyperplasia, disappeared or decreased in 100% and 96.5% of patients respectively, whereas the Operative-Link on Gastritis-Assessment and Operative-Link on Gastric-Intestinal Metaplasia stages did not change. Low-Grade Dysplasia prevalence was similar on random biopsies before and after H. pylori eradication (17.6% vs 10.6%, P = 0.19), but increased in patients with visible lesions (0% vs 22.4%, P < 0.0001). At a multivariate analysis, the probability for detecting dysplasia after resolution of H. pylori-related active inflammation was higher in patients with regression or reduction of Mucosal Associated Lymphoid Tissue hyperplasia, greater alcohol consumption, and anti-parietal cell antibody and/or anti-intrinsic factor positivity [odds ratio (OR) = 3.88, 95% confidence interval (CI): 1.31-11.49, P = 0.01; OR = 3.10, 95%CI: 1.05-9.12, P = 0.04 and OR = 5.47, 95%CI: 1.33-22.39, P < 0.04, respectively].

CONCLUSION

High-Resolution White-Light Endoscopy with Narrow-Band Imaging allows an accurate diagnosis of Low-Grade Dysplasia on visible lesions after regression of H. pylori-induced chronic gastritis. Patients with an overlap between autoimmune/H. pylori-induced gastritis may require more extensive gastric mapping.

Hellenic consensus on Helicobacter pylori infection

The Hellenic Society of Gastroenterology recently organized the "Hellenic consensus on Helicobacter pylori (H. pylori) infection". The aim of this publication is to report the guidelines in order to aid the national gastroenterology community in the management of H. pylori infection. Forty-one delegates from all Greek regions, including gastroenterologists, pathologists, clinical microbiologists, epidemiologists and basic scientists, were invited to this meeting. The participants were allocated to 1 of the 4 main topics of the meeting: i.e., H. pylori diagnosis and association with diseases; H. pylori and gastric cancer; H. pylori and extragastric associated disorders; and H. pylori treatment. The results of each subgroup were submitted to a final consensus vote that included all participants. Relevant data based on international and Greek publications were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded. The cutoff level of 70% was considered as acceptance for the final statement. It is hoped that the recommendations and conclusions of this report will guide Greek doctors in their daily practice concerning the management of H. pylori infection.

Chronic atrophic gastritis: Natural history, diagnosis and therapeutic management. A position paper by the Italian Society of Hospital Gastroenterologists and Digestive Endoscopists [AIGO], the Italian Society of Digestive Endoscopy [SIED], the Italian Society of Gastroenterology [SIGE], and the Italian Society of Internal Medicine [SIMI]

Chronic atrophic gastritis (CAG) is an underdiagnosed condition characterised by translational features going beyond the strict field of gastroenterology as it may manifest itself by a variable spectrum of gastric and extra-gastric symptoms and signs. It is relatively common among older adults in different parts of the world, but large variations exist. Helicobacter pylori-related CAG [multifocal] and autoimmune CAG (corpus-restricted) are apparently two different diseases, but they display overlapping features. Patients with cobalamin and/or iron deficiency anaemia or autoimmune disorders, including autoimmune thyroiditis and type 1 diabetes mellitus, should be offered screening for CAG. Pepsinogens, gastrin-17, and anti-H. pylori antibodies serum assays seem to be reliable non-invasive screening tools for the presence of CAG, helpful to identify individuals to refer to gastroscopy with five standard gastric biopsies in order to obtain histological confirmation of diagnosis. Patients with CAG are at increased risk of developing gastric cancer, and they should be estimated with histological staging systems (OLGA or OLGIM). H. pylori eradication may be beneficial by modifying the natural history of atrophy, but not that of intestinal metaplasia. Patients with advanced stages of CAG (Stage III/IV OLGA or OLGIM) should undergo endoscopic surveillance every three years, those with autoimmune CAG every three-five years. In patients with CAG, a screening for autoimmune thyroid disease and micronutrient deficiencies, including iron and vitamin B12, should be performed. The optimal treatment for dyspeptic symptoms in patients with CAG remains to be defined. Proton pump inhibitors are not indicated in hypochlorhydric CAG patients.

Association Between Liquid Biopsy and Prognosis of Gastric Cancer Patients: A Systematic Review and Meta-Analysis

Background: Reports regarding liquid biopsy and gastric cancer (GC) have emerged rapidly in recent decades, yet their prognostic value still remains controversial. This study was aimed to assess the impact of liquid biopsy, including circulating tumor cells (CTCs) and cell-free nucleic acids, on GC patients' prognosis.

Methods: PubMed, Medline, EMBASE, and ClinicalTrial.gov databases were searched for studies that report GC patient survival data stratified by CTC/circulating tumor DNA (ctDNA)/circulating miRNAs' status. The hazard ratios (HRs) and their 95% confidence intervals (CIs) for patients' overall survival (OS) and disease-free survival (DFS)/progression-free survival (PFS) were recorded or calculated depending on circulating target status.

Results: We initially identified 4,221 studies, from which 43 were eligible for further analysis, comprising 3,814 GC patients. Pooled analyses showed that detection of certain CTCs, ctDNA, and circulating miRNA was associated with poorer OS (CTCs: HR = 1.84, 95%CI 1.50–2.26, p < 0.001; ctDNA: HR = 1.78, 95%CI 1.36–2.34, p < 0.001; circulating miRNA: HR = 1.74, 95%CI 1.13–2.69, p < 0.001) and DFS/PFS (CTCs: HR = 3.39, 95%CI 2.21–5.20, p < 0.001; ctDNA: HR = 2.38, 95%CI 1.31–4.32, p = 0.004; circulating miRNA: HR = 3.30, 95%CI 2.39–4.55, p < 0.001) of GC patients, regardless of disease stage and time point at which sample is taken (at baseline or post-treatment).

Conclusions: The presence of CTCs and/or cellular components identifies a group of GC with poorer prognosis. Among circulating markers, CTCs demonstrated a stronger and more stable predictive value for late-stage disease and among Mongolian populations with GC. Less data are available for ctDNA and miRNA; however, their presence may also reflect aggressive biology and warrants further prospective study.

Possible indication of endoscopic resection in undifferentiated early gastric cancer

Endoscopic resection for early gastric cancer (EGC) without lymph node metastasis may be a valuable treatment option. To date, endoscopic resection for undifferentiated EGC is being investigated. We evaluated the risk of lymph node metastasis in undifferentiated EGC by examining the preoperative endoscopic findings and operated pathologic specimen. The medical records of patients who underwent surgical resection because of undifferentiated EGC between November 2008 and December 2015 were reviewed retrospectively. The risk factors associated with lymph node metastasis and the lymph node metastasis rate in the expanded indication of undifferentiated EGC were evaluated. A total of 376 patients with undifferentiated EGC (233 signet ring cell type and 143 poorly differentiated type) were analyzed. Lymph node metastasis was found in 9.8% of the patients. Among the patients who met the expanded criteria (59 patients), only one patient had lymph node metastasis (signet ring cell type without ulceration and 15 mm in size). The risk factors associated with lymph node metastasis were lesion size >20 mm (OR 3.013), scar deformity (OR 2.248), surface depression (OR 2.360), submucosal invasion (OR 3.427), and lymphovascular invasion (OR 6.296). Before endoscopic resection of undifferentiated EGC, careful selection of patients should be considered. The undifferentiated EGC with size ≥15 mm, scar deformity, surface depression, submucosal invasion, and lymphovascular invasion should be considered surgical resection instead of endoscopic resection.

Short-term outcomes of traction-assisted versus conventional endoscopic submucosal dissection for superficial gastrointestinal neoplasms: a systematic review and meta-analysis of randomized controlled studies

Background

In recent years, some traction-assisted approaches have been introduced to facilitate endoscopic submucosal dissection (ESD) procedures by reducing the procedure time and risks related to the procedure. However, the relative advantages of traction-assisted endoscopic submucosal dissection (T-ESD) are still being debated. This study aimed to assess the efficacy of T-ESD for the treatment of superficial gastrointestinal neoplasms.

Methods

We searched MEDLINE, Embase, and Cochrane library up to March 31, 2019 for randomized controlled trials (RCTs) comparing T-ESD and conventional endoscopic submucosal dissection (C-ESD) for superficial gastrointestinal neoplasms. The main endpoints are en bloc resection, complete resection, procedure time, perforation, and delayed bleeding. Pooled risk ratio (RR), Peto odds ratio (OR), and mean difference (MD) were calculated to compare T-ESD and C-ESD. This study is registered with PROSPERO, number CRD42018108135.

Results

A total of 7 RCTs with 1007 patients were included in this meta-analysis. There were no significant differences between the T-ESD and C-ESD groups in the pooled estimate of en bloc resection, complete resection, and delayed bleeding (RR = 1.00, 95% CI 0.99, 1.01, I² = 0%, P = 0.66; RR = 1.00, 95% CI 0.98, 1.03, I² = 0%, P = 0.81; OR = 0.95, 95% CI 0.48, 1.86, I² = 19%, P = 0.87,respectively). The pooled estimate indicated that the procedure time was significantly shorter in the T-ESD group (MD = − 16.19, 95% CI − 29.24, − 3.13, I² = 87%, P = 0.02) than in the C-ESD group. Compared to C-ESD, T-ESD was associated with lower incidence of perforation (OR = 0.32, 95% CI 0.11, 0.91, I² = 0%, P = 0.03).

Conclusions

T-ESD is a safe and effective treatment option with a low perforation rate and shorter procedure time than C-ESD for superficial gastrointestinal neoplasms. Future multi-center (including European populations), randomized controlled trials of larger sample size and long-term outcomes of T-ESD are required.

New European guidelines for the management of patients with precancerous changes in the stomach

Aim of the review: to analyze the current aspects of the management of patients with precancerous changes in the stomach, as outlined in the new MAPS II European recommendations.

Basic provisions. For qualified diagnosis of precancerous changes in the stomach it is necessary to use modern endoscopic and morphological methods. Timely detection of atrophy, metaplasia and dysplasia significantly increases the effectiveness of gastric cancer prevention. Eradication of Helicobacter pylori infection is an important principle in the management of patients with precancerous changes in the stomach.

Conclusion. According to European recommendations, timely diagnosis, adequate treatment and follow-up of patients with precancerous gastric changes play an important role in the prevention of stomach cancer. The application of such principles in daily clinical practice will allow standardization of the approach to the management of patients with pre-tumor pathology. 

Advanced endoscopic methods in gastrointestinal diseases: a systematic review

Endoscopic imaging is the main method for detecting gastrointestinal diseases, which adversely affect human health. White light endoscopy (WLE) was the first method used for endoscopic examination and is still the preliminary step in the detection of gastrointestinal diseases during clinical examination. However, it cannot accurately diagnose gastrointestinal diseases owing to its poor correlation with histopathological diagnosis. In recent years, many advanced endoscopic methods have emerged to improve the detection accuracy by endoscopy. Chromoendoscopy (CE) enhances the contrast between normal and diseased tissues using biocompatible dye agents. Narrow band imaging (NBI) can improve the contrast between capillaries and submucosal vessels by changing the light source acting on the tissue using special filters to realize the visualization of the vascular structure. Flexible spectral imaging color enhancement (FICE) technique uses the reflectance spectrum estimation technique to obtain individual spectral images and reconstructs an enhanced image of the mucosal surface using three selected spectral images. The i-Scan technology takes advantage of the different reflective properties of normal and diseased tissues to obtain images, and enhances image contrast through post-processing algorithms. These abovementioned methods can be used to detect gastrointestinal diseases by observing the macroscopic structure of the digestive tract mucosa, but the ability of early cancer detection is limited with low resolution. However, based on the principle of confocal imaging, probe-based confocal laser endomicroscopy (pCLE) can enable cellular visualization with high-performance probes, which can present cellular morphology that is highly consistent with that shown by biopsy to provide the possibility of early detection of cancer. Other endoscopic imaging techniques including endoscopic optical coherence tomography (EOCT) and photoacoustic endoscopy (PAE), are also promising for diagnosing gastrointestinal diseases. This review focuses on these technologies and aims to provide an overview of different technologies and their clinical applicability.

An Asian consensus on standards of diagnostic upper endoscopy for neoplasia

BACKGROUND

This is a consensus developed by a group of expert endoscopists aiming to standardise the preparation, process and endoscopic procedural steps for diagnosis of early upper gastrointestinal (GI) cancers.

METHOD

The Delphi method was used to develop consensus statements through identification of clinical questions on diagnostic endoscopy. Three consensus meetings were conducted to consolidate the statements and voting. We conducted a systematic literature search on evidence for each statement. The statements were presented in the second consensus meeting and revised according to comments. The final voting was conducted at the third consensus meeting on the level of evidence and agreement.

RESULTS

Risk stratification should be conducted before endoscopy and high risk endoscopic findings should raise an index of suspicion. The presence of premalignant mucosal changes should be documented and use of sedation is recommended to enhance detection of superficial upper GI neoplasms. The use of antispasmodics and mucolytics enhanced visualisation of the upper GI tract, and systematic endoscopic mapping should be conducted to improve detection. Sufficient examination time and structured training on diagnosis improves detection. Image enhanced endoscopy in addition to white light imaging improves detection of superficial upper GI cancer. Magnifying endoscopy with narrow-band imaging is recommended for characterisation of upper GI superficial neoplasms. Endoscopic characterisation can avoid unnecessary biopsy.

CONCLUSION

This consensus provides guidance for the performance of endoscopic diagnosis and characterisation for early gastric and oesophageal neoplasia based on the evidence. This will enhance the quality of endoscopic diagnosis and improve detection of early upper GI cancers.

Secondary endoscopic submucosal dissection for locally recurrent or incompletely resected gastric neoplasms

AIM

To investigate the feasibility and safety of secondary endoscopic submucosal dissection (ESD) for residual or locally recurrent gastric tumors.

METHODS

Between 2010 and 2017, 1623 consecutive patients underwent ESD for gastric neoplasms at a single tertiary referral center. Among these, 28 patients underwent secondary ESD for a residual or locally recurrent tumor. Our analysis compared clinicopathologic factors between primary ESD and secondary ESD groups.

RESULTS

The en bloc resection and curative rate of resection of secondary ESD were 92.9% and 89.3%, respectively. The average procedure time of secondary ESD was significantly longer than primary ESD (78.2 min vs 55.1 min, P = 0.004), and the adverse events rate was not significantly different but trended slightly higher in the secondary ESD group compared to the primary ESD group (10.7% vs 3.8%, P = 0.095). Patients who received secondary ESD had favorable outcomes without severe adverse events. During a mean follow-up period, no local recurrence occurred in patients who received secondary ESD.

CONCLUSION

Secondary ESD of residual or locally recurrent gastric tumors appears to be a feasible and curative treatment though it requires greater technical efficiency and longer procedure time.

Past and current trends in endoscopic diagnosis for early stage gastric cancer in Japan

Methodology for the diagnosis and staging of early gastric cancer (EGC) has improved in Japan since the development of the gastro-camera and determination of a definition of EGC. Imaging technology has been steadily evolving in the endoscopy field. Improvements in the resolution of standard endoscopy images used in screening and surveillance provide greater opportunities to find gastric cancer earlier. Image enhancement endoscopy (IEE), such as narrow band imaging (NBI), highlights mucosal structures and vascularity. In particular, when NBI is used with magnifying endoscopy, it reveals fine details of subtle superficial abnormalities of EGC that are difficult to recognize using standard white light endoscopy. IEE-assisted magnifying endoscopy has improved the accuracy of the differentiation of superficial gastric cancer as well as delineation of the diseased mucosa. The advanced imaging technology enables precise assessment of the risk of lymph node metastasis of EGC and is widely used to determine indications for endoscopic treatment. It is not an overstatement to say that this has become the basis for the current development and dissemination of endoscopic treatments. Moreover, the resolution of endoscopic imaging has been upgraded to the microscopy level by the development of endomicroscopy, including endocytoscopy and confocal laser endomicroscopy. Endomicroscopy allows real-time histological analysis of living tissue during routine endoscopy and may reduce the number of biopsies needed to reach the correct diagnosis, minimizing the risk of sampling errors.

Advanced endoscopic imaging in gastric neoplasia and preneoplasia

Conventional white light endoscopy remains the current standard in routine clinical practice for early detection of gastric cancer. However, it may not accurately diagnose preneoplastic gastric lesions. The technological advancements in the field of endoscopic imaging for gastric lesions are fast growing. This article reviews currently available advanced endoscopic imaging modalities, in particular chromoendoscopy, narrow band imaging and confocal laser endomicroscopy, and their corresponding evidence shown to improve diagnosis of preneoplastic gastric lesions. Raman spectrometry and polarimetry are also introduced as promising emerging technologies.

Characteristics of Missed Simultaneous Gastric Lesions Based on Double-Check Analysis of the Endoscopic Image

BACKGROUND/AIMS

The detection of multifocal lesions is important for the successful management of gastric neoplasms. We investigated the characteristics of missed simultaneous lesions and the reason for the missed diagnoses.

METHODS

A total of 140 patients who underwent repeat endoscopy before endoscopic resection between June 2013 and June 2014 were retrospectively reviewed. We classified simultaneous lesions into three groups based on a review of earlier images: group 1, no images of the location of simultaneous lesions were taken; group 2, no corresponding lesion was evident in the previous images; and group 3, simultaneous lesions were visible in the earlier images but a biopsy was not performed.

RESULTS

Simultaneous lesions were found in 12 patients (8.6%) with 13 lesions, comprising 10 dysplasia (76.9%) and three adenocarcinoma (23.1%). Regarding the reasons for missed diagnoses, seven lesions (53.8%) were classified as group 3, five (38.5%) as group 1, and the remaining lesion (7.7%) as group 2. There were no significant differences in the characteristics of the patients with and without simultaneous lesions.

CONCLUSIONS

Lesions disregarded or unnoticed during endoscopic examination were the main reason for missed diagnosis of simultaneous lesions. Endoscopists should consider the possibility of simultaneous lesions and attempt to meticulously evaluate the entire gastric mucosa.