British Society of Gastroenterology guidelines on the diagnosis and management of patients at risk of gastric adenocarcinoma

The significance of endoscopic Kyoto classification of gastritis in the gastric cancer risk assessment: A systematic review and meta‑analysis

BACKGROUND

Kyoto Classification of Gastritis is a newly proposed gastric cancer risk assessment in recent years. It selects important gastroscopic manifestations that have been reported and calculates score values. Although it has been extensively employed in clinical practice, there is no thorough review or systematic summary of its usage.

METHODS

We looked for works published before May 2022 on the correlation between the Kyoto Classification of Gastritis and gastric cancer (GC) risk in Web of Science, EMBASE, China National Knowledge Infrastructure, PubMed, Wanfang database, and other suitable sources. Statistical analysis was carried out using Stata 14.0 and RevMan 5.40. Two statistical methods were employed.

RESULTS

Eight case-control studies involving 6927 patients (continuous variables group: 1961 patients; dichotomy variables group: 4966 patients) were included, and the meta-analysis results showed a significant association between Kyoto Classification of Gastritis and GC. A Kyoto classification score ≥ 4 might indicate a risk of GC (odds ratios 7.30; 95% confidence intervals [CI] 3.62-14.72; P < .00001. There was a significant difference between gastritis and GC scores (mean difference [MD] 0.86; 95% CI 0.73-0.99; P < .00001). Moreover, we found that intestinal metaplasia and atrophy highly affected the Kyoto Classification score (MD = 0.35, MD = 0.72 95% CI 0.20-0.50,0.56-0.88). However, there was considerable heterogeneity in both statistical analyses. We found the source of heterogeneity in the first analysis method but failed to find it in the second analysis method, which may be due to the small number of studies.

CONCLUSIONS

The Kyoto Classification of gastritis score is crucial for detecting early stomach cancer. A score >4 suggests a significant risk for gastric cancer, with atrophy and intestinal metaplasia having the most impact. This score may be promoted at primary hospitals; however, because of the small number and quality of included studies, the results mentioned above need to be verified by randomized control trials with large samples and high-quality methods.

The effectiveness of a computer-aided system in improving the detection rate of gastric neoplasm and early gastric cancer: study protocol for a multi-centre, randomized controlled trial

BACKGROUND

This protocol is for a multi-centre randomised controlled trial to determine whether the computer-aided system ENDOANGEL-GC improves the detection rates of gastric neoplasms and early gastric cancer (EGC) in routine oesophagogastroduodenoscopy (EGD).

METHODS

Study design: Prospective, single-blind, parallel-group, multi-centre randomised controlled trial.

SETTINGS

The computer-aided system ENDOANGEL-GC was used to monitor blind spots, detect gastric abnormalities, and identify gastric neoplasms during EGD.

PARTICIPANTS

Adults who underwent screening, diagnosis, or surveillance EGD. Randomisation groups: 1. Experiment group, EGD examinations with the assistance of the ENDOANGEL-GC; 2. Control group, EGD examinations without the assistance of the ENDOANGEL-GC.

RANDOMISATION

Block randomisation, stratified by centre.

PRIMARY OUTCOMES

Detection rates of gastric neoplasms and EGC.

SECONDARY OUTCOMES

Detection rate of premalignant gastric lesions, biopsy rate, observation time, and number of blind spots on EGD.

BLINDING

Outcomes are undertaken by blinded assessors.

SAMPLE SIZE

Based on the previously published findings and our pilot study, the detection rate of gastric neoplasms in the control group is estimated to be 2.5%, and that of the experimental group is expected to be 4.0%. With a two-sided α level of 0.05 and power of 80%, allowing for a 10% drop-out rate, the sample size is calculated as 4858. The detection rate of EGC in the control group is estimated to be 20%, and that of the experiment group is expected to be 35%. With a two-sided α level of 0.05 and power of 80%, a total of 270 cases of gastric cancer are needed. Assuming the proportion of gastric cancer to be 1% in patients undergoing EGD and allowing for a 10% dropout rate, the sample size is calculated as 30,000. Considering the larger sample size calculated from the two primary endpoints, the required sample size is determined to be 30,000.

DISCUSSION

The results of this trial will help determine the effectiveness of the ENDOANGEL-GC in clinical settings.

TRIAL REGISTRATION

ChiCTR (Chinese Clinical Trial Registry), ChiCTR2100054449, registered 17 December 2021.

A 6-year nationwide population-based study on the current status of gastric endoscopic resection in Korea using administrative data

Gastric endoscopic resection (ER) is widely performed in Korea. This study aimed to investigate the overall status of gastric ER in Korea. We enrolled ESD or EMR cases performed for gastric cancer and adenoma from 2012 to 2017 by searching the NHIS database. The annual trend of gastric ER and the clinical characteristics were investigated. Institutions were classified into very high-, high-, low-, and very low volume centers (VHVC, HVC, LVC, and VLVC) by the procedure numbers, and institutional types, regional distributions, and medical resources were investigated accordingly. There were 175,370 ER cases during the study period, with an increasing trend over time. The average annual ESD procedure numbers were 3.9, 54.5, 249.5, and 540.3 cases in 131 VLVCs, 119 LVCs, 24 HVCs, and 12 VHVCs, respectively. Among ESD-performing institutions, 44.8% were located in the Seoul Capital Area. The distribution of medical resources showed a positive correlation with the procedural volume. Similar tendencies were also demonstrated in EMR, with some differences in hospital types and regional distribution. Gastric ER and ESD are increasing in Korea. There was a significant variance in the number of ER procedures and the distribution of types, regions, and medical resources according to the procedural volume.

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.

Genetic diversity of the oipA gene among Helicobacter pylori isolates and clinical outcome in Vietnam

Outer inflammatory protein A (OipA), which is encoded by the oipA gene, can induce interleukin-8 secretion in gastric epithelial cells. The functional status of the oipA gene is regulated by the slipped-strand mispairing mechanism based on the CT dinucleotide repeat number in the 5' region. This study aimed to investigate the oipA functional status ("on/off") of Helicobacter pylori (H. pylori) and its association with gastroduodenal diseases in southwestern Vietnam. The cross-sectional study was conducted on 173H. pylori isolates from 173 patients with gastroduodenal diseases. Sanger sequencing was used to determine the functional status of oipA. Multivariable logistic regression analysis was performed to identify the association between oipA status and gastroduodenal diseases. The oipA "on" status accounted for 96% of H. pylori isolates. Twenty-five CT repeat patterns of the oipA 5' signal region were observed, five of which were novel CT repeat patterns. The oipA "on" status was found in 100%, 97.8%, and 86.8% of H. pylori isolates from patients with peptic ulcer, precancerous lesions, and chronic gastritis, respectively (p < 0.01). The oipA "on" status was related to gastric precancerous lesions versus chronic gastritis (adjusted OR = 7.39, 95% CI: 1.35-40.59, p = 0.021) and peptic ulcers versus chronic gastritis (adjusted OR = 12.79, 95% CI: 1.19-1760.32, p = 0.033). Our data show a high prevalence of the oipA "on" status, which was associated with precancerous gastric lesions and peptic ulcers. Moreover, genetic diversity in the number and pattern of CT dinucleotide repeat of oipA among Vietnamese H. pylori strains was identified.

Global prevalence of Helicobacter pylori infection between 1980 and 2022: a systematic review and meta-analysis

BACKGROUND

Few studies have examined the temporal trends of Helicobacter pylori prevalence worldwide. We aimed to identify the changes in global prevalence of H pylori infection between 1980 and 2022.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Embase, MEDLINE, Scopus, and Web of Science, with no language restrictions, for observational studies on the prevalence of H pylori infection published between Jan 1, 1980, and Dec 31, 2022. Conference papers, meta-analyses, reviews, and case reports were excluded. We divided the study timeframe into four periods: 1980-90, 1991-2000, 2001-10, and 2011-22. Summary data were extracted from each selected publication. The prevalence of H pylori and its temporal trend were analysed according to WHO region, World Bank income level, WHO universal health coverage service coverage index of the country or region, sex and age of the patient, study type, and diagnostic method. The pooled prevalence was estimated by a random-effect meta-analysis, and the significance of the associated factors was analysed by multivariable meta-regression. This study is registered with the International Platform of Registered Systematic Review and Meta-analysis Protocols (INPLASY), 2022100026.

FINDINGS

Of the 56 967 records identified, 5236 were included in the quality assessment stage and 224 studies-from 71 countries or regions from all six WHO regions and including 2 979 179 individuals-were included in the final analysis. Significant heterogeneity was found between studies (I²=99·9%). The estimated global prevalence of H pylori infection decreased from 58·2% (95% CI 50·7-65·8) in the 1980-90 period to 43·1% (40·3-45·9) in the 2011-22 period. Prevalence was relatively static between 1991 and 2010 but declined sharply between 2011 and 2022, with the largest decline in the WHO African region. Overall, a lower prevalence of H pylori infection was reported in younger people, high-income countries, or countries with high levels of universal health coverage, and by retrospective studies. Studies based on serological diagnostic methods generally reported higher H pylori prevalence than studies based on non-serological methods (53·2% [49·8-56·6] vs 41·1% [38·1-44·2]) and fluctuated less over time.

INTERPRETATION

This meta-analysis shows a declining trend of H pylori prevalence globally, particularly in the 2011-22 period. These results could help to inform future health policy on prevention and management of this important infection. However, a considerable degree of heterogeneity exists between studies and further population-based epidemiological studies are needed.

FUNDING

None.

[Pathological evaluation of endoscopic submucosal dissection for early gastric cancer and precancerous lesion in 411 cases]

OBJECTIVE

To evaluate the pathological characteristics of endoscopic submucosal dissection (ESD) specimens for early gastric cancer and precancerous lesions, accumulating experience for clinical management and pathological analysis.

METHODS

A total of 411 cases of early gastric cancer or precancerous lesions underwent ESD. According to the Japanese guidelines for ESD treatment of early gastric cancer and classification of gastric carcinoma, the clinicopathological data, pathologic evaluation, concordance rate of pathological diagnosis between preoperative endoscopic forceps biopsies and their ESD specimens (in 400 cases), as well as the risk factors of non-curative resection of early gastric cancer, were analyzed retrospectively.

RESULTS

23.4% (96/411) of the 411 cases were adenoma/low-grade dysplasia and 76.6% (315/411) were early gastric cancer. The latter included 28.0% (115/411) non-invasive carcinoma/high-grade dysplasia and 48.7% (200/411) invasive carcinoma. The concordance rate of pathological diagnosis between endoscopic forceps biopsies and ESD specimens was 66.0% (264/400), correlating with pathological diagnosis and lesion location (P < 0.01). The rate of upgraded diagnosis and downgraded diagnosis after ESD was 29.8% (119/400) and 4.2% (17/400), respectively. Among the 315 cases of early gastric cancer, there were 277 cases (87.9%) of differentiated type and 38 cases (12.1%) of undifferentiated type. In the study, 262 cases (83.2%) met with absolute indication, while 53 cases (16.8%) met relative indication. En bloc and curative resection rates were 98.1% and 82.9%, respectively. Risk factors for non-curative resection included a long diameter >20 mm (OR=3.631, 95%CI: 1.170-11.270, P=0.026), tumor infiltration into submucosa (OR=69.761, 95%CI: 21.033-231.376, P < 0.001)and undifferentiated tumor histology (OR=16.950, 95%CI: 4.585-62.664, P < 0.001).

CONCLUSION

Several subjective and objective factors, such as the limitations of biopsy samples, the characteristics and distribution of the lesions, different pathological understanding, and the endoscopic sampling and observation, can lead to the differences between the preoperative and postoperative pathological diagnosis of ESD. In particular, the pathological upgrade of postoperative diagnosis was more significant and should receive more attention by endoscopists and pathologists. The curative resection rate of early gastric cancer in ESD was high. Non-curative resection was related to the long diameter, the depth of tumor invasion and histological classification. ESD can also be performed in undifferentiated early gastric cancer if meeting the indication criteria. The comprehensive and standardized pathological analysis of ESD specimens is clinically important to evaluate the curative effect of ESD operation and patient outcomes.

Clinical Practice Guideline for Gastritis in Korea

Gastritis is a disease characterized by inflammation of the gastric mucosa. It is very common and has various classification systems such as the updated Sydney system. As there is a lot of evidence that Helicobacter pylori infection is associated with the development of gastric cancer and that gastric cancer can be prevented by eradication, H. pylori gastritis has been emphasized recently. The incidence rate of gastric cancer in Korea is the highest in the world, and due to the spread of screening endoscopy, atrophic gastritis and intestinal metaplasia are commonly diagnosed in the general population. However, there have been no clinical guidelines developed in Korea for these lesions. Therefore, this clinical guideline has been developed by the Korean College of Helicobacter and Upper Gastrointestinal Research for important topics that are frequently encountered in clinical situations related to gastritis. Evidence-based guidelines were developed through systematic review and de novo processes, and eight recommendations were made for eight key questions. This guideline needs to be periodically revised according to the needs of clinical practice or as important evidence about this issue is published in the future.

Histopathologic findings in laparoscopic sleeve gastrectomy: is routine full pathologic evaluation indicated?

BACKGROUND

Laparoscopic sleeve gastrectomy (SG) is the most commonly performed bariatric surgery. The resected gastric segment is routinely sent for pathology evaluation. No formal national recommendation exists that mandates pathology review. We proposed to study the largest histopathologic series in SG patients yet reported.

OBJECTIVE

The primary objective of our study was to determine whether a subgroup of patients who underwent bariatric surgery in the northeastern Unites States is more susceptible to having clinically significant pathologic findings that may benefit from routine histopathologic evaluation of the gastric sleeve specimen.

SETTING

University hospital.

METHODS

A retrospective electronic chart review of patients who underwent SG at a single large academic institution was performed. Patient demographics, body mass index, and histopathologic reports of the gastric specimens obtained during SG were analyzed.

RESULTS

The records of 3543 patients were reviewed. A total of 1076 patients had abnormal pathologies, including gastritis (938), follicular gastritis (98), intestinal metaplasia (25), gastrointestinal stromal tumor (12), leiomyoma (1), lymphoma (1), and other malignancy (1). Black and Hispanic patients had a higher incidence of developing gastrointestinal stromal tumor and intestinal metaplasia. A higher incidence of Helicobacter pylori infection among specimens with abnormal pathologies was noted.

CONCLUSIONS

The findings of this study call into question the routine use of pathology workup in gastric specimens after SG. Our data suggest that such analysis may be warranted in certain subtypes of patients such as older Black and Hispanic patients in the northeastern United States.

Controlling Gastric Cancer in a World of Heterogeneous Risk

Gastric cancer (GC) is a leading cause of global mortality but also a cancer whose footprint is highly unequal. This review aims to define global disease epidemiology, critically appraise strategies of prevention and disease attenuation, and assess how these strategies could be applied to improve outcomes from GC in a world of variable risk and disease burden. Strategies of primary prevention focus on improving the detection and eradication of the main environmental risk factor, Helicobacter pylori. In certain countries of high incidence, endoscopic or radiographic screening of the asymptomatic general population has been adopted as a means of secondary prevention. By contrast, identification and targeted surveillance of individuals with precancerous lesions (such as intestinal metaplasia) is being increasingly embraced in nations of low incidence. This review also highlights existing knowledge gaps in GC prevention as well as the role of emerging technologies for early detection and risk stratification.

Orientation in upper gastrointestinal endoscopy—the only way is up

BACKGROUND

Oesophagogastroduodenoscopy is the gold standard investigation for the upper gastrointestinal (UGI) tract. Orientation during endoscopy is challenging and United Kingdom training focusses on technical competence and procedural safety. The reported location of UGI pathologies is crucial to post-endoscopic planning.

AIM

To evaluate endoscopists’ ability to spatially orientate themselves within the UGI tract.

METHODS

A cross sectional descriptive study elicited, using an anonymised survey, the ability of endoscopists to orientate themselves within the UGI tract. The primary outcome was percentage of correct answers from all surveyed; secondary outcomes were percentage of correct answers from experienced vs novice endoscopists. Pearson’s χ² test was applied to compare groups.

RESULTS

Of 188 respondents, 86 were experienced endoscopists having completed over 1000 endoscopies. 44.4% of respondents correctly identified the anterior stomach and 47.3% correctly identified the posterior of the second part of the duodenum (D2). Experienced endoscopists were significantly more likely than novice to identify the anterior stomach correctly [61.6% vs 31.3%, X² (1, n = 188) = 11.10, P = 0.001]. There was no significant difference between the two groups in identifying the posterior of D2.

CONCLUSION

The majority of endoscopists surveyed were unable to identify key landmarks within the UGI tract. Endoscopic orientation appears to improve with experience yet there are some areas still not well recognised. This has potential considerable impact on post-endoscopic management of patients with posterior duodenal ulcers being more likely to perforate and associated with a higher rebleeding risk. We suggest the development of a consensus statement on endoscopic description.

Magnifying endoscopy is superior at detecting easy-missed neoplastic lesions on the upper gastrointestinal tract

Magnifying endoscopy is advantageous in detecting precancerous lesions. Our study aimed to clarify its ability to detect easily missed neoplastic lesions on the upper gastrointestinal tract. A retrospective analysis of clinical, endoscopic, and pathological data of cases undergoing gastroscopy was performed using magnifying and routine endoscopy. The detection rates of overall lesions, the ability to identify flat-type neoplastic lesions, and the easily missed neoplastic lesions were compared between the two groups. Endoscopic data from 32,367 patients was analyzed in this study. The use of magnifying endoscopy was an independent factor in identifying flat lesions (OR 2.236, 95% CI 1.969-2.540, p < 0.001), particularly type IIb lesions (OR 3.117, 95% CI 2.333-4.165, p < 0.001). For neoplastic lesions, magnifying endoscopy was also identified as having better sensitivity than routine endoscopy (sensitivity, 90.4% vs. 78.9%, p < 0.001). Similarly, magnifying endoscopy was an independent factor for identifying flat lesions (OR 2.927, 95% CI 2.365-3.621, p < 0.001), especially type IIc lesions (OR 4.415, 95% CI 3.076-6.339, p < 0.001). Magnifying endoscopy was also identified as having superior sensitivity (44.7% vs. 13.3%, p = 0.034) for early cancerous lesions. Compared to routine endoscopy, magnification endoscopy is advantageous in detecting and identifying neoplastic lesions in the upper gastrointestinal tract, especially flat neoplastic lesions and early cancers.

Prevention of malignant digestive system tumors should focus on the control of chronic inflammation

Chronic inflammation, through a variety of mechanisms, plays a key role in the occurrence and development of digestive system malignant tumors (DSMTs). In this study, we feature and provide a comprehensive understanding of DSMT prevention strategies based on preventing or controlling chronic inflammation. The development and evaluation of cancer prevention strategies is a longstanding process. Cancer prevention, especially in the early stage of life, should be emphasized throughout the whole life course. Issues such as the time interval for colon cancer screening, the development of direct-acting antiviral drugs for liver cancer, and the Helicobacter pylori vaccine all need to be explored in long-term, large-scale experiments in the future.

Assessing the utility of pepsinogens and gastrin-17 in gastric cancer detection

OBJECTIVES

The aim of the study was to determine the proportion of gastric cancer patients with decreased levels of pepsinogen and gastrin-17 in plasma, with the goal of providing indirect evidence of the sensitivity of these biomarkers when applied in a cancer screening setting.

METHODS

The levels of pepsinogens I and II, gastrin-17, and Helicobacter pylori immunoglobulin antibodies in plasma samples of gastric cancer patients were evaluated using the GastroPanel test system (Biohit Oyj, Helsinki, Finland). A decreased level of the pepsinogen I/II ratio was defined as less than three, while a decrease in gastrin-17 was defined as less than 1 pmol/L. Univariate analysis using non-parametric tests was used to investigate differences between normal and low concentrations of biomarkers.

RESULTS

In total, 481 plasma samples from patients (59.9% male) with a median age of 64 years (ranging from 27 to 88 years) were analyzed. Out of the 400 cases of gastric cancer (83.2% of the total), 182 were categorized as the intestinal type, 141 as the diffuse type, 60 as the mixed type, and 17 as indeterminate according to the Lauren classification system. The H. pylori immunoglobulin test was positive in 74.0% of the patients. Pepsinogen I/II ratio was decreased in 32.4% (36.8% of the intestinal type); gastrin-17 in 12.3% (10.1% of the antral region) of all cases.

CONCLUSION

The majority of gastric cancer patients had normal levels of pepsinogen and gastrin-17, suggesting that these biomarkers have limited application as screening tools in the Caucasian population.

Endoscopic resection of gastric low-grade dysplasia with high risk factors is associated with decreased advanced neoplasia: a single-center retrospective cohort study

BACKGROUND

The natural course of gastric low-grade dysplasia (LGD) remains unclear, and there are inconsistent management recommendations among guidelines and consensus.

OBJECTIVE

This study aimed to investigate the incidence of advanced neoplasia in patients with gastric LGD and identify the related risk factors.

METHODS

Cases of biopsy demonstrated LGD (BD-LGD) at our center from 2010 to 2021 were reviewed retrospectively. Risk factors related to histological progression were identified, and outcomes of patients based on risk stratification were evaluated.

RESULTS

Ninety-seven (23.0%) of 421 included BD-LGD lesions were diagnosed as advanced neoplasia. Among 409 superficial BD-LGD lesions, lesion in the upper third of the stomach, H. pylori infection, larger size, and narrow band imaging (NBI)-positive findings were independent risk factors of progression. NBI-positive lesions and NBI-negative lesions with or without other risk factors had 44.7%, 1.7%, and 0.0% risk of advanced neoplasia, respectively. Invisible lesions, visible lesions (VLs) without a clear margin, and VLs with a clear margin and size ≤ 10 mm, or > 10 mm had 4.8%, 7.9%, 16.7%, and 55.7% risk of advanced neoplasia, respectively. In addition, endoscopic resection decreased the risk of cancer (P < 0.001) and advanced neoplasia (P < 0.001) in patients with NBI-positive lesions, but not in NBI-negative patients. Similar results were found in patients with VLs with clear margin and size > 10 mm. Moreover, NBI-positive lesions had higher sensitivity and lower specificity for predicting advanced neoplasia than VLs with a clear margin and size > 10 mm determined by white-light endoscopy (97.6% vs. 62.7%, P < 0.001; and 63.0% vs. 85.6%, P < 0.001, respectively).

CONCLUSION

Progression of superficial BD-LGD is associated with NBI-positive lesions, as well as with VLs with a clear margin (size > 10 mm) if NBI is unavailable, and selective resection of those lesions offers benefits for patients by decreasing the risk of advanced neoplasia.

Short-term outcomes of endoscopic submucosal dissection for the treatment of superficial gastric neoplasms in non-Asian countries: a systematic review and meta-analysis

Background

Endoscopic submucosal dissection (ESD) is now considered the standard treatment for early gastric cancer (EGC). However, the widespread adoption of ESD in western countries has been slow. We performed a systematic review to evaluate short-term outcomes of ESD for EGC in non-Asian countries.

Methods

We searched 3 electronic databases from inception until October 26, 2022. Primary outcomes were en bloc, R0 and curative resections rate by region. Secondary outcomes were overall complications, bleeding, and perforation rate by region. The proportion of each outcome, with the 95% confidence interval (CI), was pooled using a random-effects model with the Freeman-Tukey double arcsine transformation.

Results

Twenty-seven studies from Europe (n=14), South America (n=11) and North America (n=2) were included, involving 1875 gastric lesions. Overall, en bloc, R0, and curative resection rates were achieved in 96% (95%CI 94-98%), 85% (95%CI 81-89%), and 77% (95%CI 73-81%) of cases, respectively. Considering only information from lesions with adenocarcinoma, the overall curative resection was 75% (95CI 70-80%). Bleeding and perforation were observed in 5% (95%CI 4-7%) and 2% (95%CI 1-4%) of cases, respectively.

Conclusion

Our results suggest that short-term outcomes of ESD for the treatment of EGC are acceptable in non-Asian countries.

A deep-learning based system using multi-modal data for diagnosing gastric neoplasms in real-time (with video)

BACKGROUND

White light (WL) and weak-magnifying (WM) endoscopy are both important methods for diagnosing gastric neoplasms. This study constructed a deep-learning system named ENDOANGEL-MM (multi-modal) aimed at real-time diagnosing gastric neoplasms using WL and WM data.

METHODS

WL and WM images of a same lesion were combined into image-pairs. A total of 4201 images, 7436 image-pairs, and 162 videos were used for model construction and validation. Models 1-5 including two single-modal models (WL, WM) and three multi-modal models (data fusion on task-level, feature-level, and input-level) were constructed. The models were tested on three levels including images, videos, and prospective patients. The best model was selected for constructing ENDOANGEL-MM. We compared the performance between the models and endoscopists and conducted a diagnostic study to explore the ENDOANGEL-MM's assistance ability.

RESULTS

Model 4 (ENDOANGEL-MM) showed the best performance among five models. Model 2 performed better in single-modal models. The accuracy of ENDOANGEL-MM was higher than that of Model 2 in still images, real-time videos, and prospective patients. (86.54 vs 78.85%, P = 0.134; 90.00 vs 85.00%, P = 0.179; 93.55 vs 70.97%, P < 0.001). Model 2 and ENDOANGEL-MM outperformed endoscopists on WM data (85.00 vs 71.67%, P = 0.002) and multi-modal data (90.00 vs 76.17%, P = 0.002), significantly. With the assistance of ENDOANGEL-MM, the accuracy of non-experts improved significantly (85.75 vs 70.75%, P = 0.020), and performed no significant difference from experts (85.75 vs 89.00%, P = 0.159).

CONCLUSIONS

The multi-modal model constructed by feature-level fusion showed the best performance. ENDOANGEL-MM identified gastric neoplasms with good accuracy and has a potential role in real-clinic.

Rab31 promotes metastasis and cisplatin resistance in stomach adenocarcinoma through Twist1-mediated EMT

Stomach adenocarcinoma (STAD) is one of the leading causes of cancer-related death globally. Metastasis and drug resistance are two major causes of failures in current chemotherapy. Here, we found that the expression of Ras-related protein 31 (Rab31) is upregulated in human STAD tissues and high expression of Rab31 is closely associated with poor survival time. Furthermore, we revealed that Rab31 promotes cisplatin resistance and metastasis in human STAD cells. Reduced Rab31 expression induces tumor cell apoptosis and increases cisplatin sensitivity in STAD cells; Rab31 overexpression yielded the opposite result. Rab31 silencing prevented STAD cell migration, whereas the overexpression of Rab31 increased the metastatic potential. Further work showed that Rab31 mediates cisplatin resistance and metastasis via epithelial-mesenchymal transition (EMT) pathway. In addition, we found that both Rab31 overexpression and cisplatin treatment results in increased Twist1 expression. Depletion of Twist1 enhances sensitivity to cisplatin in STAD cells, which cannot be fully reversed by Rab31 overexpression. Rab31 could activate Twist1 by activating Stat3 and inhibiting Mucin 1 (MUC-1). The present study also demonstrates that Rab31 knockdown inhibited tumor growth in mice STAD models. These findings indicate that Rab31 is a novel and promising biomarker and potential therapeutic target for diagnosis, treatment and prognosis prediction in STAD patients. Our data not only identifies a novel Rab31/Stat3/MUC-1/Twist1/EMT pathway in STAD metastasis and drug resistance, but it also provides direction for the exploration of novel strategies to predict and treat STAD in the future.

Phosphomannomutase 2 (PMM2) variants leading to hyperinsulinism-polycystic kidney disease are associated with early-onset inflammatory bowel disease and gastric antral foveolar hyperplasia

Phosphomannomutase 2 (PMM2) deficiency causes Congenital Disorder of Glycosylation (PMM2-CDG), but does not have a recognised association with Inflammatory Bowel Disease (IBD). A distinct clinical syndrome of hyperinsulinism and autosomal recessive polycystic kidney disease (HIPKD) arises in the context of a specific variant in the PMM2 promotor, either in homozygosity, or compound heterozygous with a deleterious PMM2 variant. Here, we describe the development of IBD in three patients with PMM2-HIPKD, with onset of IBD at 0, 6, and 10 years of age. In each case, intestinal inflammation coincided with the unusual finding of gastric antral foveolar hyperplasia. IBD disease was of variable severity at onset but well controlled with conventional and first-line biologic treatment approaches. The organ-level pattern of disease manifestations in PMM2-HIPKD-IBD may reflect a loss of cis-acting regulatory control by hepatocyte nuclear factor 4 alpha (HNF4A). Analysis of published transcriptomic data suggests that IBD most likely arises due to an impact on epithelial cellular function. We identify a specific pattern of variation in PMM2 as a novel association of early-onset IBD with distinctive gastric pathology.

A root cause analysis system to establish the most plausible explanation for post-endoscopy upper gastrointestinal cancer

BACKGROUND : Missing upper gastrointestinal cancer (UGIC) at endoscopy may prevent curative treatment. We have developed a root cause analysis system for potentially missed UGICs at endoscopy (post-endoscopy UGIC [PEUGIC]) to establish the most plausible explanations. METHODS : The electronic records of patients with UGIC at two National Health Service providers were examined. PEUGICs were defined as UGICs diagnosed 6-36 months after an endoscopy that did not diagnose cancer. An algorithm based on the World Endoscopy Organization post-colonoscopy colorectal cancer algorithm was developed to categorize and identify potentially avoidable PEUGICs. RESULTS : Of 1327 UGICs studied, 89 (6.7 %) were PEUGICs (patient median [IQR] age at endoscopy 73.5 (63.5-81.0); 60.7 % men). Of the PEUGICs, 40 % were diagnosed in patients with Barrett's esophagus. PEUGICs were categorized as: A - lesion detected, adequate assessment and decision-making, but PEUGIC occurred (16.9 %); B - lesion detected, inadequate assessment or decision-making (34.8 %); C - possible missed lesion, endoscopy and decision-making adequate (8.9 %); D - possible missed lesion, endoscopy or decision-making inadequate (33.7 %); E - deviated from management pathway but appropriate (5.6 %); F - deviated inappropriately from management pathway (3.4 %). The majority of PEUGICs (71 %) were potentially avoidable and in 45 % the cancer outcome could have been different if it had been diagnosed on the initial endoscopy. There was a negative correlation between endoscopists' mean annual number of endoscopies and the technically attributable PEUGIC rate (correlation coefficient -0.57; P = 0.004). CONCLUSION : Missed opportunities to avoid PEUGIC were identified in 71 % of cases. Root cause analysis can standardize future investigation of PEUGIC and guide quality improvement efforts.

A Global Perspective on Gastric Cancer Screening: Which Concepts Are Feasible, and When?

BACKGROUND

Gastric cancer (GC) remains the fifth most common cancer and the third most common cause of cancer-related death globally. In 2022, GC fell into the scope of the updated EU recommendations for targeted cancer screening. Given the growing awareness of the GC burden, we aimed to review the existing screening strategies for GC in high-risk regions and discuss potentially applicable modalities in countries with low-to-intermediate incidence.

METHODS

The references for this Review article were identified through searches of PubMed with the search terms "gastric cancer", "stomach cancer", "Helicobacter pylori", and "screening" over the period from 1995 until August 2022.

RESULTS

As Helicobacter pylori (H. pylori)-induced gastritis is the primary step in the development of GC, the focus on GC prevention may be directed toward testing for and treating this infection. Such a strategy may be appealing in countries with low- and intermediate- GC incidence. Other biomarker-based approaches to identify at-risk individuals in such regions are being evaluated. Within high-incidence areas, both primary endoscopic screening and population-based H. pylori "test-and-treat" strategies represent cost-effective models.

CONCLUSIONS

Given the significant variations in GC incidence and healthcare resources around the globe, screening strategies for GC should be adjusted to the actual conditions in each region. While several proven tools exist for accurate GC diagnosis, a universal modality for the screening of GC populations remains elusive.

A Prediction Model Based on the Risk Factors Associated with Pathological Upgrading in Patients with Early-Stage Gastric Neoplasms Diagnosed by Endoscopic Forceps Biopsy

Background/Aims

The discrepancies between the diagnosis of preoperative endoscopic forceps biopsy (EFB) and endoscopic submucosal dissection (ESD) in patients with early gastric neoplasm (EGN) exist objectively. Among them, pathological upgrading directly influences the accuracy and appropriateness of clinical decisions. The aims of this study were to investigate the risk factors for the discrepancies, with a particular focus on pathological upgrading and to establish a prediction model for estimating the risk of pathological upgrading after EFB.

Methods

We retrospectively collected the records of 978 patients who underwent ESD from December 1, 2017 to July 31, 2021 and who had a final histopathology determination of EGN. A nomogram to predict the risk of pathological upgrading was constructed after analyzing subgroup differences among the 901 lesions enrolled.

Results

The ratio of pathological upgrading was 510 of 953 (53.5%). Clinical, laboratorial and endoscopic characteristics were analyzed using univariable and binary multivariable logistic regression analyses. A nomogram was constructed by including age, history of chronic atrophic gastritis, symptoms of digestive system, blood high density lipoprotein concentration, macroscopic type, pathological diagnosis of EFB, uneven surface, remarkable redness, and lesion size. The C-statistics were 0.804 (95% confidence interval, 0.774 to 0.834) and 0.748 (95% confidence interval, 0.664 to 0.832) in the training and validation set, respectively. We also built an online webserver based on the proposed nomogram for convenient clinical use.

Conclusions

The clinical value of identifying the preoperative diagnosis of EGN lesions is limited when using EFB separately. We have developed a nomogram that can predict the probability of pathological upgrading with good calibration and discrimination value.

Vietnam Association of Gastroenterology (VNAGE) consensus on the management of Helicobacter pylori infection

Helicobacter pylori (H. pylori) infection is prevalent and has a rapidly increasing antibiotic resistance rate in Vietnam. Reinfection is quite common, and gastric carcinoma remains one of the most common malignancies, which is not uncommon to develop after successful eradication. The purpose of this consensus is to provide updated recommendations on the management of H. pylori infection in the country. The consensus panel consisted of 32 experts from 14 major universities and institutions in Vietnam who were invited to review the evidence and develop the statements using the Delphi method. The process followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The consensus level was defined as ≥80% for agreement on the proposed statements. Due to the limited availability of high-quality local evidence, this consensus was also based on high-quality evidence from international studies, especially those conducted in other populations in the Asia-Pacific region. The panel finally reached a consensus on 27 statements after two voting rounds, which consisted of four sections (1) indications for testing and selection of diagnostic tests (2), treatment regimens, (3) post-treatment confirmation of H. pylori status, and (4) reinfection prevention methods and follow-up after eradication. Important issues that require further evidence include studies on third-line regimens, strategies to prevent H. pylori reinfection, and post-eradication follow-up for precancerous gastric lesions. We hope this consensus will help guide the current clinical practice in Vietnam and promote multicenter studies in the country and international collaborations.

Kyoto classification of gastritis, virtual chromoendoscopy and artificial intelligence: Where are we going? What do we need?

Chronic gastritis (CG) is a widespread and frequent disease, mainly caused by Helicobacter pylori infection, which is associated with an increased risk of gastric cancer. Virtual chromoendoscopy improves the endoscopic diagnostic efficacy, which is essential to establish the most appropriate therapy and to enable cancer prevention. Artificial intelligence provides algorithms for the diagnosis of gastritis and, in particular, early gastric cancer, but it is not yet used in practice. Thus, technological innovation, through image resolution and processing, optimizes the diagnosis and management of CG and gastric cancer. The endoscopic Kyoto classification of gastritis improves the diagnosis and management of this disease, but through the analysis of the most recent literature, new algorithms can be proposed.

Signaling pathways of oxidative stress response: the potential therapeutic targets in gastric cancer

Gastric cancer is one of the top causes of cancer-related death globally. Although novel treatment strategies have been developed, attempts to eradicate gastric cancer have been proven insufficient. Oxidative stress is continually produced and continually present in the human body. Increasing evidences show that oxidative stress contributes significantly to the development of gastric cancer, either through initiation, promotion, and progression of cancer cells or causing cell death. As a result, the purpose of this article is to review the role of oxidative stress response and the subsequent signaling pathways as well as potential oxidative stress-related therapeutic targets in gastric cancer. Understanding the pathophysiology of gastric cancer and developing new therapies for gastric cancer depends on more researches focusing on the potential contributors to oxidative stress and gastric carcinogenesis.

Research trends in endoscopic applications in early gastric cancer: A bibliometric analysis of studies published from 2012 to 2022

Background

Endoscopy is the optimal method of diagnosing and treating early gastric cancer (EGC), and it is therefore important to keep up with the rapid development of endoscopic applications in EGC. This study utilized bibliometric analysis to describe the development, current research progress, hotspots, and emerging trends in this field.

Methods

We retrieved publications about endoscopic applications in EGC from 2012 to 2022 from Web of Science™ (Clarivate™, Philadelphia, PA, USA) Core Collection (WoSCC). We mainly used CiteSpace (version 6.1.R3) and VOSviewer (version 1.6.18) to perform the collaboration network analysis, co-cited analysis, co-occurrence analysis, cluster analysis, and burst detection.

Results

A total of 1,333 publications were included. Overall, both the number of publications and the average number of citations per document per year increased annually. Among the 52 countries/regions that were included, Japan contributed the most in terms of publications, citations, and H-index, followed by the Republic of Korea and China. The National Cancer Center, based in both Japan and the Republic of Korea, ranked first among institutions in terms of number of publications, citation impact, and the average number of citations. Yong Chan Lee was the most productive author, and Ichiro Oda had the highest citation impact. In terms of cited authors, Gotoda Takuji had both the highest citation impact and the highest centrality. Among journals, Surgical Endoscopy and Other Interventional Techniques had the most publications, and Gastric Cancer had the highest citation impact and H-index. Among all publications and cited references, a paper by Smyth E C et al., followed by one by Gotoda T et al., had the highest citation impact. Using keywords co-occurrence and cluster analysis, 1,652 author keywords were categorized into 26 clusters, and we then divided the clusters into six groups. The largest and newest clusters were endoscopic submucosal dissection and artificial intelligence (AI), respectively.

Conclusions

Over the last decade, research into endoscopic applications in EGC has gradually increased. Japan and the Republic of Korea have contributed the most, but research in this field in China, from an initially low base, is developing at a striking speed. However, a lack of collaboration among countries, institutions, and authors, is common, and this should be addressed in future. The main focus of research in this field (i.e., the largest cluster) is endoscopic submucosal dissection, and the topic at the frontier (i.e., the newest cluster) is AI. Future research should focus on the application of AI in endoscopy, and its implications for the clinical diagnosis and treatment of EGC.

Histopathologic Diagnosis Discrepancies Between Preoperative Endoscopic Forceps Biopsies and Specimens Resected by Endoscopic Submucosal Dissection in Superficial Gastric Neoplasms

BACKGROUND

The standard of practice when a superficial lesion was identified during upper GI endoscopy is to take an endoscopic forceps biopsy (EFB) of the lesion. The histopathologic findings then will determine the management plan. Endoscopic submucosal dissection (ESD) enables en-bloc resection for early neoplasms of the gastrointestinal tract and provides an adequate specimen that permits a more reliable histopathologic assessment. The objective of this study was to determine the rate of histopathologic discrepancy between EFB and specimens resected by ESD, and to identify the predisposing risk factors for this discordance.

MATERIALS AND METHODS

This is a retrospective study, enrolling patients with superficial gastric neoplasms that underwent EFB followed by ESD. We divided cases to concordant or discordant group according to the histopathologic diagnosis of EFB and ESD specimens. We also analyzed the features that may have influenced the occurrence of histopathologic discordance and the association between discordant samples of adenocarcinoma and neoplastic invasion to deeper layers.

RESULTS

A total of 115 gastric ESD procedures were performed with 84 patients meeting the inclusion criteria. Histopathologic discordance between EFB and ESD specimens were observed in 35.8% of cases (30/84 lesions). The univariant-bivariant analysis and multivariate logistic regression analysis showed that histologic discordance was closely related to the size of the lesions ( P =0.028).

CONCLUSION

Histopathologic discrepancy between EFB and ESD specimens may occur in approximately one-third of cases, particularly for lesions over 20 mm, which may lead to crucial delays in gastric cancer precise diagnosis and treatment.

Construction of anoikis-related lncRNAs risk model: Predicts prognosis and immunotherapy response for gastric adenocarcinoma patients

Background: Anoikis acts as a programmed cell death that is activated during carcinogenesis to remove undetected cells isolated from ECM. Further anoikis based risk stratification is expected to provide a deeper understanding of stomach adenocarcinoma (STAD) carcinogenesis. Methods: The information of STAD patients were acquired from TCGA dataset. Anoikis-related genes were obtained from the Molecular Signatures Database and Pearson correlation analysis was performed to identify the anoikis-related lncRNAs (ARLs). We performed machine learning algorithms, including Univariate Cox regression and Least Absolute Shrinkage and Selection Operator (Lasso) analyses on the ARLs to build the OS-score and OS-signature. Clinical subgroup analysis, tumor mutation burden (TMB) detection, drug susceptibility analysis, immune infiltration and pathway enrichment analysis were further performed to comprehensive explore the clinical significance. Results: We established a STAD prognostic model based on five ARLs and its prognostic value was verified. Survival analysis showed that the overall survival of high-risk score patients was significantly shorter than that of low-risk score patients. The column diagrams show satisfactory discrimination and calibration. The calibration curve verifies the good agreement between the prediction of the line graph and the actual observation. TIDE analysis and drug sensitivity analysis showed significant differences between different risk groups. Conclusion: The novel prognostic model based on anoikis-related lncRNAs we identified could be used for prognosis prediction and precise therapy in gastric adenocarcinoma.

Deep learning-assisted diagnosis of chronic atrophic gastritis in endoscopy

Background

Chronic atrophic gastritis (CAG) is a precancerous condition. It is not easy to detect CAG in endoscopy. Improving the detection rate of CAG under endoscopy is essential to reduce or interrupt the occurrence of gastric cancer. This study aimed to construct a deep learning (DL) model for CAG recognition based on endoscopic images to improve the CAG detection rate during endoscopy.

Methods

We collected 10,961 endoscopic images and 118 video clips from 4,050 patients. For model training and testing, we divided them into two groups based on the pathological results: CAG and chronic non-atrophic gastritis (CNAG). We compared the performance of four state-of-the-art (SOTA) DL networks for CAG recognition and selected one of them for further improvement. The improved network was called GAM-EfficientNet. Finally, we compared GAM-EfficientNet with three endoscopists and analyzed the decision basis of the network in the form of heatmaps.

Results

After fine-tuning and transfer learning, the sensitivity, specificity, and accuracy of GAM-EfficientNet reached 93%, 94%, and 93.5% in the external test set and 96.23%, 89.23%, and 92.37% in the video test set, respectively, which were higher than those of the three endoscopists.

Conclusions

The CAG recognition model based on deep learning has high sensitivity and accuracy, and its performance is higher than that of endoscopists.

Endoscopic surveillance with systematic random biopsy for the early diagnosis of hereditary diffuse gastric cancer: a prospective 16-year longitudinal cohort study

BACKGROUND

Hereditary diffuse gastric cancer, generally caused by germline pathogenic variants in CDH1, presents with early-onset signet ring cell carcinoma. Prophylactic total gastrectomy is the definitive treatment. Endoscopic surveillance can inform the timing of prophylactic total gastrectomy through detection of microscopic signet ring cell carcinoma foci. However, evidence is scarce about the optimal endoscopic sampling technique and characterisation of signet ring cell carcinoma foci in hereditary diffuse gastric cancer. We aimed to formally assess the diagnostic yield of different sampling strategies and to identify criteria for the characterisation of endoscopic lesions.

METHODS

For this prospective longitudinal cohort study, we included individuals aged 18 years or older at the Cambridge University Hospitals National Health Service (NHS) Foundation Trust who fulfilled testing criteria for hereditary diffuse gastric cancer between June 1, 2005, and July 31, 2021. The primary outcome was detection of intramucosal signet ring cell carcinoma foci. We assessed the detection rate and anatomical location of signet ring cell carcinoma in random biopsy samples taken according to a systematic protocol compared with biopsies targeted to endoscopic findings. Endoscopic lesions were examined with white-light and narrow band imaging with magnification to assess the likelihood of cancerous foci.

FINDINGS

145 individuals were included, of whom 68 (47%) were male and 92 (63%) carried the CDH1 pathogenic variant. 58 (40%) patients were diagnosed with invasive signet ring cell carcinoma over a median follow-up time of 51 months (IQR 18-80). The first diagnosis of signet ring cell carcinoma was most commonly made from random biopsies (29 [50%] of 58 patients), rather than targeted biopsies (15 [26%] patients). The anatomical distribution of signet ring cell carcinoma foci detected by random biopsies more accurately reflected those identified in prophylactic total gastrectomy specimens than did targeted biopsies. Omitting random biopsies in our cohort would have led to an under-diagnosis rate of 42%. Using a novel panel of endoscopic criteria, gastric lesions containing signet ring cell carcinoma were predicted with a sensitivity of 67·3% and a specificity of 90·2%.

INTERPRETATION

Random biopsies enhance the early detection of signet ring cell carcinoma and are complementary to targeted biopsies in surveillance of hereditary diffuse gastric cancer. This sampling method should be the standard of care when performing all surveillance endoscopies for individuals with hereditary diffuse gastric cancer.

FUNDING

UK Medical Research Council.

Tumor heterogeneity and carcinoma in resected specimens of gastric low-grade dysplasia: A retrospective single center study

Lesions diagnosed as gastric low-grade dysplasia (LGD) may be pathologically upgraded to early gastric cancer (EGC) or high-grade dysplasia (HGD) after endoscopic resection (ER). In this study, we investigated the risk factors for pathological upgrades after ER and assessed the reason for these upgrades by retrospectively analyzing ER data between January 1999 and December 2019. We enrolled patients with LGD confirmed by forceps biopsy; the patients were classified into pathologically concordant (LGD) and upgraded (HGD and EGC) groups according to the pathology of their resected specimen. To determine the risk factors for upgrade, we compared the endoscopic findings of the concordant and upgraded groups via 1:1 matched case-control design. To find the reasons for discordance, all upgraded cases were pathologically re-evaluated. Among 1,643 cases of LGD, pathological upgrades were observed in 423 (25.7%) resected specimens and EGC was found in 111 (6.7%) lesions. After matching the upgraded and concordant cases, lesion sizes exceeding 1.5 cm (odds ratio (OR): 1.8; 95% CI: 1.1-3.0), mucosal nodularity (OR: 10.8; 95% CI: 5.6-21.0), heterogeneous color (OR: 3.0; 95% CI: 1.7-5.3), presence of erosion (OR: 2.7; 95% CI: 1.8-5.3), and open-type gastric atrophy (OR: 2.9; 95% CI: 1.7-4.9) were noted to be significantly associated with upgraded pathology to EGC. Among the EGC cases, 99 (89.2%) were found to have pre-existing dysplasia. In conclusion, endoscopic evaluations should be performed because of possible pathological upgrades and co-existence of carcinomas in LGDs, especially when they exhibit surface nodularity, erosion, heterogeneous color, and large size.

Where do we stand in AI for endoscopic image analysis? Deciphering gaps and future directions

Recent developments in deep learning have enabled data-driven algorithms that can reach human-level performance and beyond. The development and deployment of medical image analysis methods have several challenges, including data heterogeneity due to population diversity and different device manufacturers. In addition, more input from experts is required for a reliable method development process. While the exponential growth in clinical imaging data has enabled deep learning to flourish, data heterogeneity, multi-modality, and rare or inconspicuous disease cases still need to be explored. Endoscopy being highly operator-dependent with grim clinical outcomes in some disease cases, reliable and accurate automated system guidance can improve patient care. Most designed methods must be more generalisable to the unseen target data, patient population variability, and variable disease appearances. The paper reviews recent works on endoscopic image analysis with artificial intelligence (AI) and emphasises the current unmatched needs in this field. Finally, it outlines the future directions for clinically relevant complex AI solutions to improve patient outcomes.

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.

Endoscopic Surveillance and Treatment of Upper GI Tract Lesions in Patients with Familial Adenomatous Polyposis-A New Perspective on an Old Disease

Familial adenomatous polyposis (FAP) is an autosomal dominant disease caused by a germline mutation in the adenomatous polyposis coli (APC) gene. Patients with FAP develop up to thousands of colorectal adenomas as well as lesions in the upper GI tract. In FAP, the upper digestive lesions include gastric fundic gland polyps (FGPs), antrum adenomas, duodenal or small intestinal adenomas, and carcinoma. Patients, after colectomy, are still at significant risk for extracolonic malignancies. Advances in endoscope resolution and optical enhancement technologies allow endoscopists to provide assessments of benign and malignant polyps. For this reason, in the past decades, endoscopic resection techniques have become the first line of treatment in patients with polyps in the upper GI, whereby polyps and even early cancers can be successfully cured. In FAP patients, endoscopic ampullectomy appears to be a safe and effective way of treating patients with ampullary tumors. According to current indications, endoscopic retrograde cholangiopancreatography (ERCP) and stenting of the main pancreatic duct follow ampullectomy.

Clinical and endoscopic predictors of gastric precancerous conditions: a large population case control study

BACKGROUND

Atrophic gastritis (AG) and gastric intestinal metaplasia (GIM) are well defined intermediate precancerous conditions (PCCs) in the gastric cancer cascade. The diagnosis of PCCs may be suspected based on endoscopic findings but is established by histology. Estimates of the global prevalence of PCCs vary widely but simple clinical or endoscopic predictors of their diagnosis are ill defined. We aimed to evaluate the prevalence of gastric PCCs in our practice and to identify predictors for its diagnosis.

METHODS

We analyzed electronic reports of patients referred for gastroscopy procedures over a 5-year period and included those for whom gastric biopsies were performed. We investigated demographic, clinical, and endoscopic findings to identify possible association with histologic detection of gastric PCCs and performed multivariate analysis to identify predictors of its diagnosis.

RESULTS

A total of 4930 patients with full endoscopic and histologic data were included for the final analysis. Of these, 806 (16.3%) patients had a histologic diagnosis of gastric PCCs. Demographic and clinical variables including male sex (51.4% vs. 45.7%; P=0.003), age over 60 (69.8% vs. 45.2%; P<0.001), and anemia indication for gastroscopy (17.6% vs. 14.8%; P=0.04) were significantly associated with gastric PCCs diagnosis. Likewise, endoscopic findings of Barret's esophagus (2.6% vs. 1.3%; P=0.006), atrophic gastritis according to endoscopist's judgment (12.9% vs. 3.5%; P<0.01) and corpus predominant gastritis (22.5% vs. 14.7%; P=0.02) were significantly associated with gastric PCCs. In multivariate analysis, age>60 (please explain all acronyms HR 2.51, 95% CI 2.12-2.96), male sex (HR 1.235, 95% CI 1.05-1.44), corpus predominant (HR 1.284, 95% CI 1.04-1.57), and atrophic gastritis (HR 4, 95% CI 3.07-5.21) were independent predictors for PCCs diagnosis.

CONCLUSIONS

Not uncommonly encountered in our practice, a judicious performance of gastric biopsies to detect gastric PCCs should be adopted especially in older, male patients with endoscopic findings of corpus predominant and/or gastric atrophy.

The Effect of Quadruple Therapy with Polaprezinc or Bismuth on Gut Microbiota after Helicobacter pylori Eradication: A Randomized Controlled Trial

Background: Quadruple therapy with polaprezinc provided an alternative to Helicobacter pylori eradication; however, the effect on gut microbiota remains uncertain. This study aims to identify whether polaprezinc-containing quadruple therapy causes adverse microbiota effects among asymptomatic adults, compared with bismuth therapy. Methods: This was a randomized control trial. One hundred asymptomatic H. pylori-infected adults were randomly (1:1) assigned to two treatment groups (polaprezinc-containing therapy, PQT; or bismuth-containing therapy, BQT). Fecal samples were collected from subjects before and 4−8 weeks after therapy. Samples were sequenced for the V4 regions of the 16S rRNA gene. Results: The relative abundance of the three dominant bacterial phyla (Bacteroidota, Firmicutes, and Proteobacteria) accounted for more than 95% of each treatment group. The alpha diversity between eradications that succeeded and those that failed had no significant difference (p > 0.05). After successful eradication, the alpha diversity in the BQT group decreased in comparison with the baseline (p < 0.05). Subjects who were successfully eradicated by BQT showed considerably lower alpha diversity indices than those of the PQT at follow-up (p < 0.05). The abundance of Parasutterella in subjects who were successfully eradicated by PQT was four times greater than that of BQT (q < 0.05). Conclusion: A 14-day PQT may be superior to BQT in maintaining short-term gut microbiota homeostasis after H. pylori treatment. Our findings preliminarily provide evidence of the short-term impacts of the gut microbiota after PQT treatment of H. pylori infection.

When malignancy hits twice – synchronous gastric carcinoma and non-Hodgkin-B-cell lymphoma in a patient with common variable immunodeficiency

Patients with common variable immunodeficiency (CVID) generally bear a higher risk of non Hodgkin B-cell lymphomas and solid tumors, in particular gastric adenocarcinoma.

Here we report a case of a 58-year-old male CVID patient who developed both malignancies within a very short period, as documented by two subsequent esophagogastroduodenoscopies performed within 4 months. While the first upper gastrointestinal endoscopy for routine surveillance purposes was uneventful, the second one after developing unexplained weight loss revealed two new neoplastic lesions in the stomach. The histological evaluation revealed a poorly differentiated adenocarcinoma infiltrating the muscularis propria forcing gastrectomy as well as a high-grade B-non-Hodgkin-lymphoma with detection of a MYC- and BCL6-translocation, necessitating chemotherapy with R-CHOP.

This case emphasizes the necessity of high awareness for gastric neoplasia in patients with CVID and highlights the need of a standardized yet not established endoscopic surveillance protocol for this vulnerable group.

Cost comparison of oral, transnasal and magnet assisted capsule endoscopy in the examination of the upper gastrointestinal tract in patients with dyspepsia

Introduction

Conventional oral upper gastrointestinal (GI) endoscopy can obe uncomfortable. By comparison, transnasal endoscopy (TNE) and magnet assisted capsule endoscopy (MACE) have superior tolerability. A cost comparison of competing upper GI endoscopic modalities have yet to be performed.

Methods

We performed a cost comparison study of oral, TNE and MACE by a combination of activity-based costing and averaging of fixed costs over 24 481 upper GI endoscopies performed for dyspepsia over a 10-year period.

Results

On average, 9.4 procedures were performed daily. TNE was cheapest at €125.90 per procedure, costing 30% less than oral endoscopy at €184.10 and threefold cheaper than MACE at €407.10. Flexible endoscope reprocessing cost €53.80. TNE was cheaper than oral endoscopy as sedation was not required. Oral endoscopies have a further rate of infectious complications, estimated to cost €16.20 per oral procedure in inpatient admissions. Oral and TNE equipment are more expensive to purchase and maintain than MACE costing €79 330 and €81 819, respectively compared with MACE at €15 420 per annum. However, capsule endoscopes cost significantly more per procedure at €369.00 than the consumables for flexible endoscopy (per oral €12.30, TNE €5.30).

Conclusions

TNE cost less to perform than conventional per oral endoscopy. The cost of capsule endoscopes will need to be reduced significantly if routine use is to be expected.

Evolution of the Correa's cascade steps: A long-term endoscopic surveillance among non-ulcer dyspepsia and gastric ulcer after H. pylori eradication

BACKGROUND

This study is aimed toward investigating the evolution of each Correa's step after Helicobacter pylori eradication in a long-term follow-up and exploring the factors correlated with a high-risk of gastric cancer.

METHODS

A total of 1824 H. pylori-infected subjects were enrolled to receive screening endoscopy. Among them, 491 received surveillance endoscopy. The patients were divided into Correa's steps I to VI, from normal to gastric cancer. A group-based trajectory model was used to classify patients as persistent high-risk status or not.

RESULTS

The prevalence rates of positive corpus-predominant gastritis index (CGI) were 20%-40% in all age groups and Correa's steps IV-V increased >35% after 50 years based on screening endoscopy. Successful eradication of H. pylori regressed CGI after the 1st year-and-thereafter (P < 0.05) and decreased Correa's step progression (Relative risk 0.66 [95% CI 0.49-0.89], P = 0.01); however, it did not regress OLGA and OLGIM. Not only in steps IV-V, but also in step III, the patients had a risk of developing gastric cancer (11.13-76.41 and 4.61 per 1000 person-years). Age (Hazard ratio 1.012 [1.003-1.020], P = 0.01), OLGA stages ≥ I (2.127 [1.558-2.903], P < 0.001), and OLGIM stages ≥ I (1.409 [1.119-1.774], P = 0.004) were correlated independently with a persistent high-risk status.

CONCLUSION

The patients in Correa's steps III-V, but not I-II, were at risk of gastric cancer after H. pylori eradication. Age, OLGA stages ≥ I, and OLGIM stages ≥ I were independent factors correlated to a persistent high-risk of gastric cancer. The data may be useful when scheduling surveillance endoscopy for subjects in each Correa's step (NCT04527055).

A deep learning method to assist with chronic atrophic gastritis diagnosis using white light images

BACKGROUND

Chronic atrophic gastritis is a common preneoplastic condition of the stomach with a low detection rate during endoscopy.

AIMS

This study aimed to develop two deep learning models to improve the diagnostic rate.

METHODS

We collected 10,593 images from 4005 patients including 2280 patients with chronic atrophic gastritis and 1725 patients with chronic non-atrophic gastritis from two tertiary hospitals. Two deep learning models were developed to detect chronic atrophic gastritis using ResNet50. The detection ability of the deep learning model was compared with that of three expert endoscopists.

RESULTS

In the external test set, the diagnostic accuracy of model 1 for detecting gastric antrum atrophy was 0.890. The identification accuracies for the severity of gastric antrum atrophy were 0.773 and 0.590 in the internal and external test sets, respectively. In the other two external sets, the detection accuracies of model 2 for chronic atrophic gastritis were 0.854 and 0.916, respectively. Deep learning model 1's ability to identify gastric antrum atrophy was comparable to that of human experts.

CONCLUSION

Deep-learning-based models can detect chronic atrophic gastritis with good performance, which may greatly reduce the burden on endoscopists, relieve patient suffering, and improve the disease's detection rate in primary hospitals.

Cytokine profile in patients with atrophic gastritis in comorbidity with thyroid gland pathology

Background. Optimization of the management of patients with precancerous conditions of the stomach in comorbid pathology is an urgent task of gastroenterology. The purpose of the study: to evaluate the content of pro- and anti-inflammatory cytokines, as well as the level of vascular endothelial growth factor (VEGF) at different degrees of vascularization of the thyroid gland in patients with atrophic gastritis. Materials and methods. A study was conducted in 120 patients with atrophic gastritis and thyroid pathology. All of them underwent a sonological examination of the thyroid gland using an ultrasound scanner Toshiba Xario (Japan), which revealed poor vascularization of the parenchyma in 82 (68.3%) cases, moderate vascularization was diagnosed in 20 (16.7%) patients and marked— in 18 (15.0%). Quantitative content of cytokines (interleukins (IL) 8, 10, 18, tumor necrosis factorα), vascular endothelial growth factor in the blood serum was determined by immunoenzymatic assay using Vector-Best reagents. Results. Among patients with poor vascularization, only atrophic changes of the gastric mucosa were diagnosed in almost half— 39 (47.6%) people, while dysplastic changes of the gastric mucosa were found in a third of patients with marked vascularization. Intestinal metaplasia was detected in half of cases, regardless of the degree of vascularization of the thyroid parenchyma. Cytokine imbalance was found in patients with atrophic gastritis, with the greatest shift in case of marked vascularization of the thyroid parenchyma due to a 4-fold increase in the level of pro-inflammatory cytokines IL-8 (р<0.05) and by 1.7 times of IL-18 (p<0.05), with a simultaneous decrease in the content of the anti-inflammatory cytokine IL-10 by 3.2 times (p<0.05) compared to control indicators. The level of VEGF in the blood serum of patients with atrophic gastritis with moderate and marked vascularization of the thyroid parenchyma was significantly increased by 1.5 (p<0.05) and 1.7 times (p<0.05), respectively, compared to that of people with poor vascularization. Correlations were revealed between the degree of vascularization of the thyroid parenchyma and the level of IL-8 (r=0.491; p=0.031) and VEGF (r=0.444; p=0.019) in patients with atrophic gastritis. Conclusions. Patients with atrophic gastritis had a cytokine imbalance, which deepens as the vascularization of the thyroid gland increases that is possibly related to common pathogenetic mechanisms of the development of comorbid pathology.

Gastric intestinal metaplasia development in African American predominant United States population

BACKGROUND

Gastric cancer significantly contributes to cancer mortality globally. Gastric intestinal metaplasia (GIM) is a stage in the Correa cascade and a premalignant lesion of gastric cancer. The natural history of GIM formation and progression over time is not fully understood. Currently, there are no clear guidelines on GIM surveillance or management in the United States.

AIM

To investigate factors associated with GIM development over time in African American-predominant study population.

METHODS

This is a retrospective longitudinal study in a single tertiary hospital in Washington DC. We retrieved upper esophagogastroduodenoscopies (EGDs) with gastric biopsies from the pathology department database from January 2015 to December 2020. Patients included in the study had undergone two or more EGDs with gastric biopsy. Patients with no GIM at baseline were followed up until they developed GIM or until the last available EGD. Exclusion criteria consisted of patients age < 18, pregnancy, previous diagnosis of gastric cancer, and missing data including pathology results or endoscopy reports. The study population was divided into two groups based on GIM status. Univariate and multivariate Cox regression was used to estimate the hazard induced by patient demographics, EGD findings, and Helicobacter pylori (H. pylori) status on the GIM status.

RESULTS

Of 2375 patients who had at least 1 EGD with gastric biopsy, 579 patients were included in the study. 138 patients developed GIM during the study follow-up period of 1087 d on average, compared to 857 d in patients without GIM (P = 0.247). The average age of GIM group was 64 years compared to 56 years in the non-GIM group (P < 0.001). In the GIM group, adding one year to the age increases the risk for GIM formation by 4% (P < 0.001). Over time, African Americans, Hispanic, and other ethnicities/races had an increased risk of GIM compared to Caucasians with a hazard ratio (HR) of 2.12 (1.16, 3.87), 2.79 (1.09, 7.13), and 3.19 (1.5, 6.76) respectively. No gender difference was observed between the study populations. Gastritis was associated with an increased risk for GIM development with an HR of 1.62 (1.07, 2.44). On the other hand, H. pylori infection did not increase the risk for GIM.

CONCLUSION

An increase in age and non-Caucasian race/ethnicity are associated with an increased risk of GIM formation. The effect of H. pylori on GIM is limited in low prevalence areas.

Noninvasive detection and interpretation of gastrointestinal diseases by collaborative serum metabolite and magnetically controlled capsule endoscopy

Gastrointestinal diseases are complex diseases that occur in the gastrointestinal tract. Common gastrointestinal diseases include chronic gastritis, peptic ulcers, inflammatory bowel disease, and gastrointestinal tumors. These diseases may manifest a long course, difficult treatment, and repeated attacks.

Gastroscopy and mucosal biopsy are the gold standard methods for diagnosing gastric and duodenal diseases, but they are invasive procedures and carry risks due to the necessity of sedation and anesthesia. Recently, several new approaches have been developed, including serological examination and magnetically controlled capsule endoscopy (MGCE). However, serological markers lack lesion information, while MGCE images lack molecular information.

This study proposes combining these two technologies in a collaborative noninvasive diagnostic scheme as an alternative to the standard procedures. We introduce an interpretable framework for the clinical diagnosis of gastrointestinal diseases. Based on collected blood samples and MGCE records of patients with gastrointestinal diseases and comparisons with normal individuals, we selected serum metabolite signatures by bioinformatic analysis, captured image embedding signatures by convolutional neural networks, and inferred the location-specific associations between these signatures.

Our study successfully identified five key metabolite signatures with functional relevance to gastrointestinal disease. The combined signatures achieved discrimination AUC of 0.88. Meanwhile, the image embedding signatures showed different levels of validation and testing accuracy ranging from 0.7 to 0.9 according to different locations in the gastrointestinal tract as explained by their specific associations with metabolite signatures. Overall, our work provides a new collaborative noninvasive identification pipeline and candidate metabolite biomarkers for image auxiliary diagnosis. This method should be valuable for the noninvasive detection and interpretation of gastrointestinal and other complex diseases.

Dysplastic Stem Cell Plasticity Functions as a Driving Force for Neoplastic Transformation of Precancerous Gastric Mucosa

BACKGROUND & AIMS

Dysplasia carries a high risk of cancer development; however, the cellular mechanisms for dysplasia evolution to cancer are obscure. We have previously identified 2 putative dysplastic stem cell (DSC) populations, CD44v6neg/CD133+/CD166+ (double positive [DP]) and CD44v6+/CD133+/CD166+ (triple positive [TP]), which may contribute to cellular heterogeneity of gastric dysplasia. Here, we investigated functional roles and cell plasticity of noncancerous Trop2+/CD133+/CD166+ DSCs initially developed in the transition from precancerous metaplasia to dysplasia in the stomach.

METHODS

Dysplastic organoids established from active Kras-induced mouse stomachs were used for transcriptome analysis, in vitro differentiation, and in vivo tumorigenicity assessments of DSCs. Cell heterogeneity and genetic alterations during clonal evolution of DSCs were examined by next-generation sequencing. Tissue microarrays were used to identify DSCs in human dysplasia. We additionally evaluated the effect of casein kinase 1 alpha (CK1α) regulation on the DSC activities using both mouse and human dysplastic organoids.

RESULTS

We identified a high similarity of molecular profiles between DP- and TP-DSCs, but more dynamic activities of DP-DSCs in differentiation and survival for maintaining dysplastic cell lineages through Wnt ligand-independent CK1α/β-catenin signaling. Xenograft studies demonstrated that the DP-DSCs clonally evolve toward multiple types of gastric adenocarcinomas and promote cancer cell heterogeneity by acquiring additional genetic mutations and recruiting the tumor microenvironment. Last, growth and survival of both mouse and human dysplastic organoids were controlled by targeting CK1α.

CONCLUSIONS

These findings indicate that the DSCs are de novo gastric cancer-initiating cells responsible for neoplastic transformation and a promising target for intervention in early induction of gastric cancer.

The active form of Helicobacter pylori vacuolating cytotoxin induces decay-accelerating factor CD55 in association with intestinal metaplasia in the human gastric mucosa

High-level expression of decay-accelerating factor, CD55, has previously been found in human gastric cancer (GC) and intestinal metaplasia (IM) tissues. Therapeutic effects of CD55 inhibition in cancer have been reported. However, the role of Helicobacter pylori infection and virulence factors in the induction of CD55 and its association with histological changes of the human gastric mucosa remain incompletely understood. We hypothesised that CD55 would be increased during infection with more virulent strains of H. pylori, and with more marked gastric mucosal pathology. RT-qPCR and immunohistochemical analyses of gastric biopsy samples from 42 H. pylori-infected and 42 uninfected patients revealed that CD55 mRNA and protein were significantly higher in the gastric antrum of H. pylori-infected patients, and this was associated with the presence of IM, but not atrophy, or inflammation. Increased gastric CD55 and IM were both linked with colonisation by vacA i1-type strains independently of cagA status, and in vitro studies using isogenic mutants of vacA confirmed the ability of VacA to induce CD55 and sCD55 in gastric epithelial cell lines. siRNA experiments to investigate the function of H. pylori-induced CD55 showed that CD55 knockdown in gastric epithelial cells partially reduced IL-8 secretion in response to H. pylori, but this was not due to modulation of bacterial adhesion or cytotoxicity. Finally, plasma samples taken from the same patients were analysed for the soluble form of CD55 (sCD55) by ELISA. sCD55 levels were not influenced by IM and did not correlate with gastric CD55 mRNA levels. These results suggest a new link between active vacA i1-type H. pylori, IM, and CD55, and identify CD55 as a molecule of potential interest in the management of IM as well as GC treatment. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.