Screening for gastric cancer in Asia: current evidence and practice

Design of Low-Cost Endoscope Based on Novel Wire-Driven Rotary Valve and Water-Jet Mechanism

To improve the prevalence of screening for gastric cancer in low-income areas, a low-cost endoscope based on a novel wire-driven rotary valve and water-jet mechanism is proposed. The primary component of this endoscope is a rotary valve whose core is driven by a stepper motor through a flexible wire, which controls the direction of the water jet. This enables it to reach any point in the workspace by controlling the valve core angle and water-jet intensity. The envelope surface of the endoscope tip trajectory is likely a hemisphere. The horizontal diameter of the working space projection is approximately 350 mm, which is sufficient to observe most parts of the greater curvature of the stomach. The image-acquisition performance of the designed endoscope was satisfactory in a phantom experiment. The introduction of the novel rotary valve greatly simplifies the structure and reduces the cost of the proposed endoscope. With low cost and high portability, this endoscope provides a good alternative for early gastric cancer screening in low- and middle-income areas.

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.

Preferences of first-degree relatives of gastric cancer patients for gastric cancer screening: a discrete choice experiment

BACKGROUND

It is very necessary to implement gastric cancer screening in China to reduce the mortality of gastric cancer, but there are no national screening guidelines and programs. Understanding of individual preferences is conducive to formulating more acceptable screening strategies, and discrete choice experiments can quantify individual preferences. In addition, the first-degree relatives of gastric cancer patients are at high risk for gastric cancer. Compared with those without a family history of gastric cancer, the risk of gastric cancer in first-degree relatives of gastric cancer patients is increased by 60%. Therefore, a discrete choice experiment was carried out to quantitatively analyse the preferences of first-degree relatives of gastric cancer patients for gastric cancer screening to serve as a reference for the development of gastric cancer screening strategies.

METHODS

A questionnaire was designed based on a discrete choice experiment, and 342 first-degree relatives of gastric cancer patients were investigated. In STATA 15.0 software, the data were statistically analysed using a mixed logit model.

RESULTS

The five attributes included in our study had a significant influence on the preferences of first-degree relatives of gastric cancer patients for gastric cancer screening (P < 0.05). Participants most preferred the sensitivity of the screening program to be 95% (coefficient = 1.424, P < 0.01) with a willingness to pay 2501.902 Yuan (95% CI, 738.074-4265.729). In addition, the participants' sex and screening experiences affected their preferences. An increase in sensitivity 35 to 95% had the greatest impact on the participants' willingness to choose a gastric cancer screening program.

CONCLUSION

The formulation of gastric cancer screening strategies should be rooted in people's preferences. The influence of sex differences and screening experiences on the preferences of people undergoing screening should be considered, and screening strategies should be formulated according to local conditions to help them play a greater role.

A Case Study on Modeling the Time to Recurrence of Gastric Cancer Patients

BACKGROUND

Gastric cancer is a malignant tumor of the stomach and it is one of the leading causes of death worldwide. The study aimed to model the time to first recurrence of gastric cancer patients at the Tikur Anbesa specialized hospital.

METHODS

The data for this study were gastric cancer patients followed up from January 1, 2013 to February 29, 2020 at Tikur Anbesa Specialized Hospital, Oncology Center, Addis Ababa. We used Weibull, log-logistic and lognormal as baseline hazard functions with the gamma and the inverse Gaussian frailty distributions. Data analyzed with the statistical software R.

RESULTS

The median recurrence time of the patients was about 23.96 months with a maximum recurrence time of 60.81 months, of which about 61.2% had first recurrences of gastric cancer. The clustering effect is significant in modeling the time to recurrence of gastric cancer. According to the result of the log-logistic inverse Gaussian frailty model, the sex of the patient, the tumor size, smoking habit, the treatment carried out, the vascular invasion, the stage of the disease, the helicobacter pylori infection and the histological type were the significant prognostic factors  at 5% level of significance.

CONCLUSION

Inverse Gaussian frailty model is the model that best describes the time to recurrence of the gastric cancer data set. Gender of the patients, tumor size, treatment taken, vascular invasion, disease stage, helicobacter pylori infection and histological type were the determining prognostic factors. This requires measures to improve patient health and prevent relapse based on significant risk factors, and particular attention should be paid to patients with such factors.

Well differentiated carcinoma with a poor prognosis: a retrospective analysis of papillary gastric adenocarcinoma

PURPOSE

To explore the clinicopathological features and prognosis of papillary gastric adenocarcinoma (PGC).

METHODS

The subjects of this retrospective analysis were 1525 patients with gastric cancer in a single center in China.

RESULTS

The patients with PGC were generally of advanced age and the tumor was located in the upper 1/3 of the stomach. PGC was well or moderately differentiated, with serosal infiltration, early lymph node metastasis, TNM stages I/II, liver metastasis, and a short postoperative overall survival time. Patients with the secondary pathological type of papillary adenocarcinoma presented with clinicopathological similarities to those with primary PGC. PGC was a risk factor for poor survival in both univariate and multivariate analyses.

CONCLUSION

Papillary gastric adenocarcinoma (PGC) showed different clinicopathological characteristics and prognosis to other types of gastric cancer (GC), even if it was not the primary pathological type. The higher the proportion of papillary adenocarcinoma in gastric cancer samples, the shorter the postoperative survival time of patients. PGC needs further multicenter studies.

Clinicopathological features and prognosis of developed gastric cancer based on the diagnosis of mucosal atrophy and enlarged folds of stomach by double-contrast upper gastrointestinal barium X-ray radiography

BACKGROUND

Mucosal atrophy and enlarged folds of stomach by double-contrast upper gastrointestinal barium X-ray radiography (UGI-XR) are two major features of Helicobacter pylori-induced chronic gastritis. These were previously shown to be risk indicators of gastric cancer, but their predictability for clinicopathological characters of developed gastric cancer is unelucidated. In addition, evidence for decreasing the mortality of gastric cancer by appropriate follow-up of UGI screening is needed.

METHODS

The 5134 generally healthy UGI-XR examinees, who underwent follow-up UGI-XR or upper gastrointestinal endoscopy (UGI-ES) more than once, were prospectively observed for 10 years.

RESULTS

At the beginning of follow-up, 1515 (29.5%) had mucosal atrophy and 990 (19.5%) had enlarged folds. For the serum anti-H. pylori IgG, 1301 (25.3%) were positive, 177 (3.4%) were possibly positive, and 3656 (71.2%) were negative. During the 10-year observation period, gastric cancer developed in 15 subjects, among which 13 had mucosal atrophy and 10 had enlarged folds. These two features were expectedly useful indicators for gastric cancer incidence, but they showed no significant association with tumor stage or histological type of developed cancer. Only one of the 5134 subjects died of gastric cancer during 10 years, which was significantly lower than the predicted number of gastric cancer death (6.78 for 10 years) according to the mortality rate in Japan.

CONCLUSIONS

Neither mucosal atrophy nor enlarged folds of stomach showed a significant association with clinicopathological features of developed gastric tumors. Appropriate follow-up of cancer screening by UGI-XR or UGI-ES can reduce the risk of gastric cancer-related death.

L-Menthol for Gastrointestinal Endoscopy: A Systematic Review and Meta-Analysis

In randomized controlled trials, L-menthol inhibits gastrointestinal peristalsis during endoscopy. Our goal was to quantitatively synthesize the available evidence to evaluate the efficacy and safety of L-menthol for gastrointestinal endoscopy.

Long-Term Follow-up of Gastric Precancerous Lesions in a Low GC Incidence Area

Data on the evolution of gastric precancerous lesions (GPL), especially in countries of a Low gastric cancer incidence area are limited. Our objective was to study a long-term evolution of GPL in France.

International cost-effectiveness analysis evaluating endoscopic screening for gastric cancer for populations with low and high risk

BACKGROUND

Gastric cancer remains one of the 3 most common causes of cancer death worldwide. Understanding the health and economic factors that affect screening cost-effectiveness in different countries will help address when and where it makes most sense to screen for gastric cancer.

METHODS

We performed a cost-effectiveness analysis using a Markov model to compare screening and surveillance strategies for gastric cancer in Brazil, France, Japan, Nigeria, and the United States. Primary outcome was the incremental cost-effectiveness ratio. We then performed a sensitivity analysis to determine how each variable affected the overall model.

RESULTS

In all countries, the most cost-effective strategies, measured by incremental cost-effectiveness ratio relative to no screening, were screening every 10 years, surveillance of high- and low-risk patients every 5 and 10 years, respectively, and screening every 5 years. Only Japan had at least one cost-effective screening strategy. The most important variables across different screening strategies and countries were starting age of screening, cost of endoscopy, and baseline probability of local gastric cancer at time of diagnosis.

CONCLUSIONS

Our model suggests that screening for gastric cancer is cost-effective in countries with higher incidence and lower costs of screening, but screening may still be a viable option in high-risk populations within low incidence countries.

Endoscopic Screening and Surveillance for Gastric Cancer

Gastric cancer is one of the most common cancers worldwide. Gastric cancer is a multifactorial disease, and the incidence varies widely by geographic region, with half of new cases occurring in East Asia. Population-based nationwide screening for gastric cancer has been implemented in some Eastern Asian countries such as South Korea and Japan. In these countries, endoscopic screening decreased gastric cancer mortality. Endoscopic screening seems to be a cost-effective modality in countries with high incidence of gastric cancer. However, the usefulness of population-based screening has not yet been proved in countries with low incidence of gastric cancer.

Global Patterns and Trends in Gastric Cancer Incidence Rates (1988-2012) and Predictions to 2030

BACKGROUND & AIMS

The long-term trend in gastric cancer rates has rarely been reported from a global perspective. We aimed to explore the past temporal trends (1988-2012) in gastric cancer incidence rates in 43 countries and to predict future trends (2012-2030).

METHODS

Data on yearly gastric cancer incidence by age group and sex were drawn from 108 cancer registries in 43 countries in the Cancer Incidence in Five Continents Time Trends (CI5plus) database. Age-standardized incidence rates per 100,000 persons were computed from 1988-2012. The number of new cases and incidence rates were predicted to 2030 using the Bayesian age-period-cohort model.

RESULTS

Persistent decreasing trends in gastric cancer incidence rates were observed from 1988-2012 worldwide, with an overall average annual percentage change of -2.1% (95% confidence interval, -2.5--1.7). The trends will continue or remain stable until 2030 in most of the selected countries except for Ecuador and Lithuania, whose gastric cancer incidence rates will experience substantially increasing trends in the next several decades.

CONCLUSION

The incidence rates of gastric cancer are expected to decrease through 2030 in most countries except Ecuador and Lithuania. Reductions in smoking and Helicobacter pylori prevalence and improvement in diet probably contributed to the decrease. Gastric cancer still represents a major cancer burden worldwide, and the large number of gastric cancer cases worldwide may still call for lifestyle interventions in terms of smoking and diet and massive efforts for H pylori screening and treatment, especially in countries with predicted increasing incidence rates of gastric cancer.

SNHG10/DDX54/PBX3 Feedback Loop Contributes to Gastric Cancer Cell Growth

BACKGROUND

The importance of long noncoding RNAs (lncRNAs) has been identified in human cancers, such as emerged as tumor facilitator or tumor suppressor. Small nucleolar RNA host gene 10 (SNHG10) has been reported as an oncogenic lncRNA in hepatocellular carcinoma. However, its functional role and underlying mechanism in gastric cancer (GC) need to be further explored.

AIMS

Our study was conducted to investigate the function and molecular mechanism of SNHG10 in GC.

METHODS

SNHG10 expression was detected by qRT-PCR. The effect of SNHG10 on GC cell growth was assessed by colony formation, EdU, JC-1, flow cytometry, and wound-healing assays. The interaction between SNHG10 and PBX3 was confirmed through ChIP and luciferase reporter assay. RIP and RNA pull down assays was used to define the binding of DEAD-box helicase 54 (DDX54) to SNHG10 or PBX homeobox 3 (PBX3).

RESULTS

SNHG10 was expressed at a high level in GC cells. SNHG10 knockdown resulted in the inhibition on GC cell proliferation, migration but induced cell apoptosis. PBX3 could interact with SNHG10 promoter and thereby activate the expression of SNHG10. Subsequently, it was confirmed that SNHG10 positively modulated the expression of PBX3. Based on this, we found that DDX54 could bind to SNHG10 and PBX3, suggesting that SNHG10 maintained PBX3 mRNA stability through recruiting DDX54. Restoration assays indicated that PBX3 overexpression recovered SNHG10 silencing-induced inhibition on GC cell growth.

CONCLUSIONS

SNHG10 facilitates cell growth by affecting DDX54-mediated PBX3 mRNA stability in GC.

Mist1 Inhibits Epithelial-Mesenchymal Transition in Gastric Adenocarcinoma via Downregulating the Wnt/β-catenin Pathway

As a secretory cell transcription factor, muscle intestine stomach expression 1 (Mist1) is associated with serous secretory cell development and gastric chief cell maturation. Here, we focus on the function of Mist1 in gastric adenocarcinoma carcinogenesis. Based on clinical data and a mouse model of gastric cancer, we found that Mist1 expression was reduced in gastric cancer. Then, we overexpressed Mist1 using a lentivirus system and found that overexpression of Mist1 could inhibit gastric cancer cell proliferation, migration and invasion in vitro. Additionally, in vivo, we assessed the function of Mist1 in a gastric cancer xenograft model and distant pulmonary metastasis model. Overexpression of Mist1 decreased tumour growth and distant metastasis in vivo, suggesting that Mist1 acts as a tumour suppressor in gastric carcinogenesis. Furthermore, Mist1 overexpression inhibited epithelial-mesenchymal transition (EMT) in gastric cancer by suppressing β-catenin transcription activity and then the Wingless and INT-1 (Wnt)/β-catenin signalling pathway, which could be reversed by a Wnt/β-catenin-specific agonist. In conclusion, this study indicated that overexpression of Mist1 could reverse EMT in gastric carcinogenesis by inhibiting the Wnt/β-catenin signalling pathway and that Mist1 might be a novel marker for early gastric cancer screening.

Cost-benefit of serum pepsinogen screening for gastric adenocarcinoma in the Mexican population

INTRODUCTION AND AIM

Helicobacter pylori (H. pylori) is known to be capable of causing chronic inflammation of the gastric mucosa that slowly progresses through the premalignant stages, reaching localized gastric adenocarcinoma (GAC). Its outcome is closely related to the stage at which diagnosis is made. The aim of the present study was to determine cost-benefit by comparing esophagogastroduodenoscopy, serum pepsinogen detection, and no screening at all.

MATERIAL AND METHODS

Utilizing Markov chains and Monte Carlo simulation, the costs and effects of various detection modalities were simulated to analyze the cost-benefit of each strategy. For our population, we used the published data of patients with gastric cancer, applicable to the Mexican population.

RESULTS

The results were reported as incremental cost-effectiveness ratios. The best strategy was serum pepsinogen determination, followed by the strategy of endoscopic examination with continued monitoring every 3 years.

CONCLUSIONS

The performance of serum pepsinogen serology and directed endoscopic examination (and continued monitoring, if necessary) for GAC screening could be a cost-effective intervention in Mexico, despite the low-to-moderate general prevalence of the disease.

The Correlation Between Mutant p53 Protein Expression and Cell Atypia in Early Differentiated Gastric Adenocarcinoma

Objective

This study aims to explore the correlation between the expression of mutant p53 protein and cellular atypia in early differentiated gastric adenocarcinoma (DGA).

Methods

A total of 107 cases of early DGA samples resected by endoscopic submucosal dissection (ESD) were collected from the Pathology Department of Beijing Friendship Hospital from January 2018 to December 2019. The EnVision two-step immunohistochemical method was used to detect the expression of mutant p53 protein in these cancer tissues, and the correlation with cell atypia was analyzed.

Results

In early DGA tissues, the expression rate of mutant p53 protein was significantly higher than in normal gastric mucosa (P < 0.01). However, the expression of mutant p53 protein was not correlated to age or gender (P > 0.05) but to the location of the tumor, depth of invasion, and degree of differentiation (P < 0.01). The expression of mutant p53 protein was closely correlated to cell atypia. Furthermore, this was weakly positive in low-grade atypical adenocarcinoma but strongly positive or negative in high-grade atypical adenocarcinoma, and there was a significant difference between these two (P < 0.01).

Conclusion

Mutant p53 protein is highly expressed in early DGA, which can be used as an auxiliary index for the diagnosis of early gastric cancer. The different expression patterns of mutant p53 protein in high-grade and low-grade atypical gastric cancers suggest that these may have different genetic changes.

Chinese and global burdens of gastric cancer from 1990 to 2019

BACKGROUND

Gastric cancer is a common cancer in China. This project investigated the disease burden of gastric cancer from 1990 to 2019 in China and globally.

METHODS

The global age-standardized rates (ASRs) were extracted from the Global Burden of Disease. Moreover, the estimated annual percentage changes (eAPCs) in the ASRs of incidence (ASIR), mortality (ASMR), and disability-adjusted life-years (DALYs) were calculated to determine the trends by countries and regions.

RESULTS

In China, the ASIR declined from 37.56 to 30.64 per 100,000 and the ASMR declined from 37.73 to 21.72 per 100,000. The global ASIR decreased from 22.44 to 15.59 and the ASMR declined from 20.48 to 11.88 per 100,000 persons from 1990 to 2019. The ASIR was the lowest in Malawi (3.28 per 100,000) and the highest in Mongolia (43.7 per 100,000), whereas the ASMR was the lowest in the United States of America (3.40 per 100,000) and the highest in Mongolia (40.04 per 100,000) in 2019. The incidence of early-onset gastric cancer increased in China. The DALYs attributed to gastric cancer presented a slight decrease during the period. China had a higher mortality/incidence ratio (0.845) and 5-year prevalence (27.6/100,000) than most developed countries.

CONCLUSION

China presented a steady decline in the incidence and mortality rates for gastric cancer. The global ASIR, ASMR, and DALYs showed a slight rise decrease. Different patterns of gastric cancer rates and temporal trends have been identified in different geographical regions, indicating that specific strategies are needed to prevent the increase in some countries.

Screening value for gastrointestinal lesions of magnetic-controlled capsule endoscopy in asymptomatic individuals

BACKGROUND AND AIM

Most patients with gastric tumors and precancerous lesions are asymptomatic, which often results in delayed diagnosis and treatment. Compared with conventional gastroscopy and capsule endoscopy, magnetic-controlled capsule endoscopy is a non-invasive, effective, and cost-efficient diagnostic modality for gastric examination. We retrospectively investigated magnetic-controlled capsule endoscopy as a screening tool for gastrointestinal lesions (particularly gastric tumors and precancerous lesions) in asymptomatic individuals.

METHODS

In this retrospective study, 1757 patients who voluntarily underwent magnetic-controlled capsule endoscopy between January and December 2019 at nine medical centers across Shaanxi province based on strict inclusion and exclusion criteria were enrolled. The primary outcomes were gastric tumor and precancerous lesion detection rates and procedural safety.

RESULTS

The upper and lower gastrointestinal lesion detection rates were 98.35% (1728/1757) and 21.61% (78/361), respectively; 2.28% of patients were diagnosed with gastric tumors including gastric cancer (4/1757) and submucosal tumors (36/1757). Three types of precancerous lesions were found in 591 patients (33.64%), including chronic atrophic gastritis (23.16%), gastric polyp (10.98%), and gastric ulcer (2.96%). For patients aged over 40 years, the detection rate of precancerous lesions was higher (14.36% vs 42.58%, P < 0.001). No patient was diagnosed with small intestinal cancer. No adverse events occurred.

CONCLUSIONS

Magnetic-controlled capsule endoscopy could be used as a promising novel screening modality for diagnosis of gastrointestinal lesions in asymptomatic individuals, specifically gastric tumors and precancerous lesions, with the advantages of safety, non-invasiveness, effectiveness, and cost-efficiency.

Development and validation of a serum microRNA biomarker panel for detecting gastric cancer in a high-risk population

OBJECTIVE

An unmet need exists for a non-invasive biomarker assay to aid gastric cancer diagnosis. We aimed to develop a serum microRNA (miRNA) panel for identifying patients with all stages of gastric cancer from a high-risk population.

DESIGN

We conducted a three-phase, multicentre study comprising 5248 subjects from Singapore and Korea. Biomarker discovery and verification phases were done through comprehensive serum miRNA profiling and multivariant analysis of 578 miRNA candidates in retrospective cohorts of 682 subjects. A clinical assay was developed and validated in a prospective cohort of 4566 symptomatic subjects who underwent endoscopy. Assay performance was confirmed with histological diagnosis and compared with Helicobacter pylori (HP) serology, serum pepsinogens (PGs), 'ABC' method, carcinoembryonic antigen (CEA) and cancer antigen 19-9 (CA19-9). Cost-effectiveness was analysed using a Markov decision model.

RESULTS

We developed a clinical assay for detection of gastric cancer based on a 12-miRNA biomarker panel. The 12-miRNA panel had area under the curve (AUC)=0.93 (95% CI 0.90 to 0.95) and AUC=0.92 (95% CI 0.88 to 0.96) in the discovery and verification cohorts, respectively. In the prospective study, overall sensitivity was 87.0% (95% CI 79.4% to 92.5%) at specificity of 68.4% (95% CI 67.0% to 69.8%). AUC was 0.848 (95% CI 0.81 to 0.88), higher than HP serology (0.635), PG 1/2 ratio (0.641), PG index (0.576), ABC method (0.647), CEA (0.576) and CA19-9 (0.595). The number needed to screen is 489 annually. It is cost-effective for mass screening relative to current practice (incremental cost-effectiveness ratio=US$44 531/quality-of-life year).

CONCLUSION

We developed and validated a serum 12-miRNA biomarker assay, which may be a cost-effective risk assessment for gastric cancer.

TRIAL REGISTRATION NUMBER

This study is registered with ClinicalTrials.gov (Registration number: NCT04329299).

Breath analysis for the detection of digestive tract malignancies: systematic review

Background

In recent decades there has been growing interest in the use of volatile organic compounds (VOCs) in exhaled breath as biomarkers for the diagnosis of multiple variants of cancer. This review aimed to evaluate the diagnostic accuracy and current status of VOC analysis in exhaled breath for the detection of cancer in the digestive tract.

Methods

PubMed and the Cochrane Library database were searched for VOC analysis studies, in which exhaled air was used to detect gastro-oesophageal, liver, pancreatic, and intestinal cancer in humans, Quality assessment was performed using the QUADAS-2 criteria. Data on diagnostic performance, VOCs with discriminative power, and methodological information were extracted from the included articles.

Results

Twenty-three articles were included (gastro-oesophageal cancer n = 14, liver cancer n = 1, pancreatic cancer n = 2, colorectal cancer n = 6). Methodological issues included different modalities of patient preparation and sampling and platform used. The sensitivity and specificity of VOC analysis ranged from 66.7 to 100 per cent and from 48.1 to 97.9 per cent respectively. Owing to heterogeneity of the studies, no pooling of the results could be performed. Of the VOCs found, 32 were identified in more than one study. Nineteen were reported as cancer type-specific, whereas 13 were found in different cancer types. Overall, decanal, nonanal, and acetone were the most frequently identified.

Conclusion

The literature on VOC analysis has documented a lack of standardization in study designs. Heterogeneity between the studies and insufficient validation of the results make interpretation of the outcomes challenging. To reach clinical applicability, future studies on breath analysis should provide an accurate description of the methodology and validate their findings.

The Diagnostic Value of Serum Gastrin-17 and Pepsinogen for Gastric Cancer Screening in Eastern China

OBJECTIVE

To evaluate the diagnostic value of gastrin-17 (G-17) and pepsinogen (PG) in gastric cancer (GC) screening in China, especially eastern China, and to determine the best diagnostic combination and threshold (cutoff values) to screen out patients who need gastroscopy.

METHODS

The serum concentrations of G-17 and pepsinogen I and II (PGI and PGII) in 834 patients were analyzed, and the PGI/PGII ratio (PGR) was calculated. According to pathological results, patients can be divided into chronic nonatrophic gastritis (NAG)/chronic atrophic gastritis (CAG)/intraepithelial neoplasia (IN)/GC groups. The differences in G-17, PG, and PGR in each group were analyzed, and their values in GC diagnosis were evaluated separately and in combination.

RESULTS

There were differences in serum G-17, PGII, and PGR among the four groups (NAG/CAG/IN/GC) (P ≤ 0.001). In total, 54 GC cases were diagnosed, of which 50% were early GC. There was no significant difference in the PGI levels among the four groups (P = 0.377). NAG and CAG composed the chronic gastritis (CG) group. The G-17 and PGII levels in the IN and GC groups were higher than those in the CG group (both P ≤ oth C), while the PGR levels were lower (P ≤ lower). When distinguishing NAG from CAG, the best cutoff value for G-17 was 9.25 pmol/L, PGII was 7.06 μg/L, and PGR was 12.07. When distinguishing CG from IN, the best cutoff value for G-17 was 3.86 pmol/L, PGII was 11.92 μg/L, and PGR was 8.26. When distinguishing CG from GC, the best cutoff value for G-17 was 3.89 pmol/L, PGII was 9.16 μg/L, and PGR was 14.14. The sensitivity, specificity, accuracy, and positive and negative predictive values of G-17/PGII/PGR for GC diagnosis were 83.3%/70.4%/79.6%, 51.8%/56.3%/47.8%, 53.8%/57.2%/49.9%, 10.7%/10.9%/9.6%, and 97.8%/96.5%/97.1%, respectively. The sensitivity, specificity, accuracy, and positive predictive and negative predictive values of PGII/G-17 vs. PGR/G-17 vs. PGR/PGII in the diagnosis of GC were 63.0% vs. 70.4% vs. 64.8%, 70.5% vs. 70.1% vs. 60.4%, 70.0% vs. 70.1% vs. 60.7%, 12.9% vs. 14.0% vs. 10.2%, and 96.5% vs. 97.2% vs. 96.1%, respectively.

CONCLUSION

The PGII and G-17 levels in patients with gastric IN and GC were significantly increased, while the serum PGR level was significantly decreased. Serological detection is effective for screening GC. The combination of different markers can improve the diagnostic efficiency. The highest diagnostic accuracy was G-17 combined with PGR, and the best cutoff values were G - 17 > 3.89 pmol/L and PGR < 14.14.

Opportunistic upper endoscopy during colonoscopy as a screening strategy for countries with intermediate gastric cancer risk

BACKGROUND AND AIM

Screening upper endoscopy can detect esophagogastric (OG) cancers early with improved outcomes. Recent cost-utility studies suggest that opportunistic upper endoscopy at the same setting of colonoscopy might be a useful strategy for screening of OG cancers, and it may be more acceptable to the patients due to cost-saving and convenience. We aim to study the diagnostic performance of this screening strategy in a country with intermediate gastric cancer risk.

METHODS

A retrospective cohort study using a prospective endoscopy database from 2015 to 2017 was performed. Patients included were individuals age > 40 who underwent opportunistic upper endoscopy at the same setting of colonoscopy without any OG symptoms. Neoplastic OG lesions are defined as cancer and high-grade dysplasia. Pre-neoplastic lesions include Barrett's esophagus (BE), intestinal metaplasia (IM), and atrophic gastritis (AG).

RESULTS

The study population involved 1414 patients. Neoplastic OG lesions were detected in five patients (0.35%). Pre-neoplastic lesions were identified in 174 (12.3%) patients. IM was found in 146 (10.3%) patients with 21 (1.4%) having extensive IM. The number needed to scope to detect a neoplastic OG lesion is 282.8 with an estimated cost of USD$141 400 per lesion detected. On multivariate regression, age ≥ 60 (RR: 1.84, 95% CI: 1.29-2.63) and first-degree relatives with gastric cancer (RR: 1.64, 95% CI: 1.06-2.55) were independent risk factors for neoplastic or pre-neoplastic OG lesion.

CONCLUSION

For countries with intermediate gastric cancer risk, opportunistic upper endoscopy may be an alternative screening strategy in a selected patient population. Prospective trials are warranted to validate its performance.

Psoas muscle depletion during preoperative chemotherapy for advanced gastric cancer has a negative impact on long-term outcomes after gastrectomy

Aim

The significance of sarcopenia in cancers has been widely recognized. However, few studies have focused on chronological changes in sarcopenia in cancer patients. This study aimed to clarify the clinical significance of changes in the psoas muscle area before and after preoperative chemotherapy.

Methods

This study included 39 patients who underwent gastrectomy followed by preoperative chemotherapy for advanced gastric cancer between January 2010 and December 2016 in our hospital. The psoas muscle area was measured at the umbilical level before and after chemotherapy, and the relationship between its chronological changes and the long‐term prognosis was examined.

Results

Patients were classified into two groups according to changes in the psoas muscle area before and after preoperative chemotherapy: remarkable muscle depletion and normal groups. No significant differences were observed in clinicopathological factors. Notably, the remarkable muscle depletion group included significantly more male patients (P = .018) and showed a high weight loss rate (P < .001). Although no significant difference was observed in the recurrence‐free survival between the two groups (P = .484), overall survival was significantly worse in the remarkable muscle depletion group (P < .001). Multivariate analysis for prognosis revealed that pathological stage III or higher (P = .022) and decreased psoas muscle area (P = .038) were independent prognostic factors.

Conclusions

The present findings suggest that psoas muscle depletion during preoperative chemotherapy is a prognostic factor for poor long‐term outcomes in patients who underwent gastrectomy followed by preoperative chemotherapy for advanced gastric cancer.

Enhanced endoscopic detection of occult gastric cancer in carriers of pathogenic CDH1 variants

BACKGROUND

Germline inactivating variants in the CDH1 tumor suppressor gene impart an elevated lifetime risk of diffuse gastric cancer. The current endoscopic surveillance method depends upon random gastric biopsies for early cancer detection.

METHODS

Asymptomatic adults with pathogenic or likely pathogenic CDH1 variants referred for endoscopic gastric cancer surveillance were included in this retrospective cohort. Upper gastrointestinal endoscopy was performed according to the consensus Cambridge method, in the early period, or a systematic (Bethesda) protocol as part of an ongoing natural history study. The primary outcome measure was cancer detection.

RESULTS

Collectively, 135 endoscopic surveillance procedures were performed in 120 patients. Twenty-six (19%, 26/135) procedures were performed using Cambridge method and 109 (81%) using the Bethesda protocol. Gastric signet ring cell carcinomas were detected in 15% (4/26) using the Cambridge method and 36% (40/109) using the Bethesda protocol (p < 0.05). Almost half (44.2%, 53/120) of patients later elected for prophylactic total gastrectomy, of whom 51 (96%, 51/53) had a signet ring cell carcinoma (T1a) discovered by histopathology. On a per endoscopy basis, the false-negative rates of detection using Cambridge method and Bethesda protocol were 80% (12/15) and 37.7% (17/45), respectively (p < 0.01).

CONCLUSIONS

Gastric cancer detection was more frequent with implementation of a systematic surveillance protocol in CDH1 variant carriers. Given the decision for prophylactic surgery is often made by patients in the context of family history and pathologic result of surveillance biopsies, we propose the Bethesda protocol offers patients an opportunity to make more informed decisions.

Clinico-pathologic determinants of non-e-curative outcome following en-bloc endoscopic submucosal dissection in patients with early gastric neoplasia

Background

Endoscopic submucosal dissection (ESD) is gaining enormous popularity in the treatment of early gastric cancers (EGCs) in many institutions across the world. However, appropriate selection of candidates for endoscopic resection is crucial to sufficiently mitigate non-e-curative (NEC) resection. This study aims at identifying the various clinico-pathologic factors that independently predict the NEC outcome and depth of submucosal invasion following ESD procedure in patients with EGC.

Methods

Multiple logistic regression analysis was applied to investigate factors that independently predict both non-curability phenomenon and the level of submucosal invasion in patients with early gastric neoplasia. Statistical Packages for the Social Sciences version 23 was used for analysis.

Results

A total of 153 patients (162 EGC lesions) underwent en-bloc ESD after which the rate of complete resection and non-e-curative outcome were 95% and 22.2%, correspondingly. Multivariate analysis depicted that tumor location in the upper two third of stomach (odds ratio [OR], 5.46; 95% confidence interval [95% CI], 1.65–18.12; p = 0.006), tumor size > 2 cm (OR, 7.63; 95% CI, 2.29–25.42; p = 0.001), histologically undifferentiated tumor (OR, 15.54; 95% CI, 1.65–146.22; p = 0.001), and tumors with 0-IIa/0-IIc or their mixed variants with predominant 0-IIa/0-IIc (OR, 9.77; 95% CI, 1.23–77.65; p = 0.031) were all independent predictors of NEC resection for early gastric tumors. Additionally, location in the upper two third of the stomach (OR, 8.88; 95% CI, 2.90–27.17; p < 0.001), ulcerated lesions (OR, 3.70; 95% CI, 1.15–11.90; p = 0.028), lesions with > 2 cm (OR, 2.94; 95% CI, 1.08–8.02; p = 0.036) and those with poor differentiation (OR, 6.51; 95% CI, 2.23–18.98; p = 0.001) were found to have significant association with submucosal invasion.

Conclusions

Tumors located in the upper two third of the stomach having a larger size (> 2 cm), poor histo-differentiation and a gross type of 0-IIa/0-IIc or their mixed variants with predominant 0-IIa/0-IIc were significantly associated with a risk of NEC after ESD procedure. Thus, early gastric tumors displaying these features need to be handled carefully during endoscopic resection. Our findings may shed light on the pre-procedural detection of clinicopathologic factors that determine non-e-curability in patients with EGC.

Study on the correlation between Helicobacter Pylori and biological characteristics of early Gastric Cancer

Objective: Retrospective analysis was used to determine the population diagnosed with EGC, and HP infection was used as the cut-off point to further evaluate the correlation between helicobacter pylori (HP) infection and tumor biological characteristics of early gastric cancer (EGC). Methods: All cases were collected from patients diagnosed with EGC through endoscopic surgery or surgical procedures from January 2009 to October 2018. General information, tumor site, tumor pathology, HER2 immunohistochemical results, and degree of HP infection were collected for retrospective analysis. Results: A total of 111 cases were collected in this study. Among the HP negative group, there were statistically significant differences in tumor sites between the uninfected group and the previously infected group (P<0.05).There were significant differences in monocyte infiltration and neutrophil infiltration between the positive and negative groups (P<0.05).The differentiated adenocarcinoma in the positive group was significantly lower than that in the negative group. The incidence rate of Mixed type cancer was significantly higher than that in the positive group (P<0.01). In the positive group of HP, there was a statistically significant difference in HER2 between the unsterilized group and the previously sterilized group (P<0.05).There was a statistically significant difference in HER2 between the HP positive group and the HP negative group (P<0.01). HP infection was significantly correlated with HER2 index and presented a positive correlation (P=0.014). Conclusion: HP infection is related to the tumor site and mucosal inflammatory infiltration of EGC. The malignant degree of EGC complicated with HP infection is higher, and most of them are mixed type. The degree of HP infection was positively correlated with the degree of invasion and malignancy of ECG. Furthermore, the tumor indicator HER2 is closely related to HP infection, and the detection of HP combined with HER2 is of great significance in the discovery of EGC and the evaluation of its malignancy.

Feasibility of Plasma-Methylated SFRP2 for Early Detection of Gastric Cancer

Gastric cancer (GC) is fifth most frequently diagnosed cancer and second leading cause of cancer in China. More than 80% of GC are diagnosed at an advanced stage due to low uptake rate of invasive screening method. The performance of methylated SFRP2 test was evaluated in 236 plasma samples, including 92 patients with GC, 16 intestinal metaplasia patients, 26 gastric fundic gland polyp patients, 13 small adenoma patients, 39 hyperplastic polyp patients, and 50 control patients. The sensitivity of plasma methylated SFRP2 was compared to serum CEA, CA72-4, CA19-9, and CA242 results in 79 patients with GC. The sensitivities for detecting GC and gastric intestinal metaplasia by methylated SFRP2 test were 60.9% and 56.3% with a specificity of 86.0%. Methylated SFRP2 test had significantly higher positive detection rate for patients with GC than gastric fundic gland polyp, small adenoma, and hyperplastic polyp patients. In 79 patients with GC, the sensitivities of CEA, CA72-4, CA19-9, and CA242 for detecting GC were 22.8%, 16.5%, 12.7%, and 11.4%. In comparison, the sensitivity of methylated SFRP2 test for detecting GC was 58.2%. Plasma methylated SFRP2 test may become a valuable tool for the noninvasive detection of GC and precursor lesions and showed higher sensitivity than serum tumor markers.

Association of Intensive Endoscopic Screening Burden With Gastric Cancer Detection

IMPORTANCE

The rapidly increasing number of gastric cancer examinations performed over a short period might influence screening performance. Accessing the association between calendar month and gastric cancer detection rates might improve policy and guide institutional support.

OBJECTIVE

To evaluate the association between the increased number of examinations over a certain period and gastric cancer detection rates among a large population included in the Korean National Cancer Screening Program (KNCSP).

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, population-based cohort study used data from the KNCSP comprising 26 765 665 men and women aged 40 years or older who participated in the screening program between January 1, 2013, and December 31, 2016. Data were analyzed from November 1, 2019, to March 31, 2020.

EXPOSURES

Gastric cancer screening with endoscopy.

MAIN OUTCOMES AND MEASURES

The primary outcome was monthly gastric cancer detection rates in the KNCSP. A negative binomial regression model was used to evaluate the association between the screening month and detection rates.

RESULTS

In total, 21 535 222 individuals underwent endoscopy (mean [SD] age, 55.61 [10.61] years; 11 761 709 women [54.62%]). The quarterly number of participants was the highest in the last quarter of the study period (2013-2014: 4 094 951 [41.39%], 2015-2016: 4 911 629 [42.19%]); this proportion was 2.48 to 2.84 times greater than that of the first quarter. Cancer detection rates were the lowest in December (2013-2014: 0.22; 95% CI, 0.22-0.23; 2015-2016: 0.21; 95% CI, 0.21-0.22); this was approximately a 40.0% to 45.0% reduction compared with the rates in January. The age group was the significant factor for monthly detection rates. After adjustment for the age group and taking account of the number of screenings, the estimated coefficient range for the screening month was negative and the detection rate in December was significantly different than in January for both the consequent cycles (2013-2014: -0.05 to -0.18; P < .001; and 2015-2016: -0.06 to -0.19; P < .001). In the multivariable logistic model, the association of calendar month with detected cancer remained after adjusting for other confounding factors (December, 2013-2014: odds ratio, 0.82; 95% CI, 0.76-0.87; P < .001; 2015-2016: odds ratio, 0.83; 95% CI, 0.79-0.89; P < .001).

CONCLUSIONS AND RELEVANCE

The findings of this cohort study suggest that the workload of endoscopists increased with the increasing number of examinations toward the end of the year, as demonstrated by the decreased cancer detection rates. These findings may help to improve gastric cancer detection rates of screening programs by controlling the monthly screening number and policy modifications.

Screening for gastric cancer in China: Advances, challenges and visions

Gastric cancer (GC) is one of the major cancers in China and all over the world. Most GCs are diagnosed at an advanced stage with unfavorable prognosis. Along with some other countries, China has developed the government-funded national screening programs for GC and other major cancers. GC screening has been shown to effectively decrease the incidence of and mortality from GC in countries adopting nationwide screening programs (Japan and Korea) and in studies based on selected Chinese populations. The screening of GC relies mostly on gastroendoscopy, the accuracy, reliability and safety of which have been indicated by previous studies. However, considering its invasive screening approach, requirements on skilled endoscopists and pathologists, and a high cost, developing noninvasive methods to amend endoscopic screening would be highly needed. Numerous studies have examined biomarkers for GC screening and the combination of biomarkers involving pepsinogen, gastrin, and Helicobacter pylori antibodies has been proposed for risk stratification, seeking to narrow down the high-risk populations for further endoscopy. Despite all the achievements of endoscopic screening, evidence on appropriate screening age, intervals for repeated screening, novel biomarkers promoting precision prevention, and health economics need to be accumulated to inform policymakers on endoscopic screening in China. With the guide of Health China 2030 Planning Outline, we have golden opportunities to promote prevention and control of GC. In this review, we summarize the characteristics of screening programs in China and other East Asian countries and introduce the past and current approaches and strategies for GC screening, aiming for featuring the latest advances and key challenges, and illustrating future visions of GC screening.

Cell-free DNA as a liquid biopsy for early detection of gastric cancer

Gastric cancer (GC) is one of the most common malignant tumors with poor prognosis worldwide, mainly due to the lack of suitable modalities for population-based screening and early detection of this disease. Therefore, novel and less invasive tests with improved clinical utility are urgently required. The remarkable advances in genomics and proteomics, along with emerging new technologies for highly sensitive detection of genetic alterations, have shown the potential to map the genomic makeup of a tumor in liquid biopsies, in order to assist with early detection and clinical management. The present review summarize the current status in the identification and development of cell-free DNA (cfDNA)-based biomarkers in GC, and also discusses their potential utility and the technical challenges in developing practical cfDNA-based liquid biopsy for early detection of GC.

Epigenetic Variation Analysis Leads to Biomarker Discovery in Gastric Adenocarcinoma

As one of the most common malignant tumors worldwide, gastric adenocarcinoma (GC) and its prognosis are still poorly understood. Various genetic and epigenetic factors have been indicated in GC carcinogenesis. However, a comprehensive and in-depth investigation of epigenetic alteration in gastric cancer is still missing. In this study, we systematically investigated some key epigenetic features in GC, including DNA methylation and five core histone modifications. Data from The Cancer Genome Atlas Program and other studies (Gene Expression Omnibus) were collected, analyzed, and validated with multivariate statistical analysis methods. The landscape of epi-modifications in gastric cancer was described. Chromatin state transition analysis showed a histone marker shift in gastric cancer genome by employing a Hidden-Markov-Model based approach, indicated that histone marks tend to label different sets of genes in GC compared to control. An additive effect of these epigenetic marks was observed by integrated analysis with gene expression data, suggesting epigenetic modifications may cooperatively regulate gene expression. However, the effect of DNA methylation was found more significant without the presence of the five histone modifications in our study. By constructing a PPI network, key genes to distinguish GC from normal samples were identified, and distinct patterns of oncogenic pathways in GC were revealed. Some of these genes can also serve as potential biomarkers to classify various GC molecular subtypes. Our results provide important insights into the epigenetic regulation in gastric cancer and other cancers in general. This study describes the aberrant epigenetic variation pattern in GC and provides potential direction for epigenetic biomarker discovery.

Association of cytotoxic T lymphocyte-associated protein 4 gene -1772T/C polymorphism with gastric cancer risk: A prisma-compliant meta-analysis

BACKGROUND

We performed a meta-analysis to more precisely evaluate the association between the cytotoxic T lymphocyte-associated protein 4 (CTLA-4) -1772T/C polymorphism and overall gastric cancer (GC) risk and the influence of ethnicity and the source of controls on that association.

METHODS

A systematic literature search was performed in PubMed, EMBASE, the Cochrane Library, Web of Science (WOS) Database, Chinese National Knowledge Infrastructure (CNKI), China biomedical literature database (CBM), Wanfang database, and VIP. Two investigators independently reviewed the articles, and disagreements were resolved by discussion and consensus. The odds ratio (OR) with 95% confidence intervals (CIs) was used to assess the strength of the association between the CTLA-4 -1722T/C polymorphism and GC risk, based on the genotype frequencies in cases and controls. The meta-analyses were performed with Stata 12.0, using two-sided P values. Trial sequential analysis (TSA) was calculated by TSA Software.

RESULTS

Overall, we identified 5 studies including 1039 GC cases and 2136 controls that evaluated the association of the CTLA-4 -1722T/C polymorphism and GC risk. Overall, there was no significant association between the CTLA-4-1722T/C polymorphism and the risk of GC. In the subgroup analysis based on ethnicity, the results showed that the relationship between the CTLA-4 -1722T/C polymorphism and GC susceptibility was strongest in the Chinese population rather than in the Iranian population (TC vs CC: OR = 1.405, 95% CI: 1.100-1.796, P = .007; TC+TT vs CC: OR = 1.329, 95% CI: 1.052-1.680, P = .017). Then, there was a significant association between the CTLA-4 -1722T/C polymorphism and the risk of GC in studies with HB controls. However, the above correlation can only be reflected in specific populations and gene models. Therefore, we believe that the evidence of this correlation is insufficient.

CONCLUSION

Our meta-analysis showed that the CTLA-4 -1722T/C polymorphism may be associated with the susceptibility to GC. However, the slight correlation can only be reflected in specific populations and gene models. Therefore, we believe that this association is negligible. The large and well-designed case-control studies are needed to validate our findings.

High expression of VCAN is an independent predictor of poor prognosis in gastric cancer

Objective

Methods

Results

Conclusion

Berberine Improves Chemo-Sensitivity to Cisplatin by Enhancing Cell Apoptosis and Repressing PI3K/AKT/mTOR Signaling Pathway in Gastric Cancer

Gastric cancer is one of the most common malignancies ranks as the second leading cause of cancer-related mortality in the world. Cisplatin (DDP) is commonly used for gastric cancer treatment, whereas recurrence and metastasis are common because of intrinsic and acquired DDP-resistance. The aim of this study is to examine the effects of berberine on the DDP-resistance in gastric cancer and explore the underling mechanisms. In this study, we established the DDP-resistant gastric cancer cells, where the IC₅₀ values of DDP in the BGC-823/DDP and SGC-7901/DDP were significantly higher than that in the corresponding parental cells. Berberine could concentration-dependently inhibited the cell viability of BGC-823 and SGC-7901 cells; while the inhibitory effects of berberine on the cell viability were largely attenuated in the DDP-resistant cells. Berberine pre-treatment significantly sensitized BGC-823/DDP and SGC-7901/DDP cells to DDP. Furthermore, berberine treatment concentration-dependently down-regulated the multidrug resistance-associated protein 1 and multi-drug resistance-1 protein levels in the BGC-823/DDP and SGC7901/DDP cells. Interestingly, the cell apoptosis of BGC-823/DDP and SGC-7901/DDP cells was significantly enhanced by co-treatment with berberine and DDP. The results from animals also showed that berberine treatment sensitized SGC-7901/DDP cells to DDP in vivo. Mechanistically, berberine significantly suppressed the PI3K/AKT/mTOR in the BGC-823/DDP and SGC-7901/DDP cells treated with DDP. In conclusion, we observed that berberine sensitizes gastric cancer cells to DDP. Further mechanistic findings suggested that berberine-mediated DDP-sensitivity may be associated with reduced expression of drug transporters (multi-drug resistance-1 and multidrug resistance-associated protein 1), enhanced apoptosis and repressed PI3K/AKT/mTOR signaling.

Inverse time trends of peptic ulcer and reflux esophagitis show significant association with reduced prevalence of Helicobacter pylori infection

INTRODUCTION

Recent prevalence and trends of gastric/duodenal ulcer (GU/DU) and reflux esophagitis (RE) are inadequate.

METHODS

We reviewed the records of consecutive 211,347 general population subjects from 1991 to 2015.

RESULTS

During the 25 years, the prevalence of GU and DU has gradually decreased (from 3.0% to 0.3% and from 2.0% to 0.3%) whereas that of RE has markedly increased (from 2.0% to 22%). The prevalence of Helicobacter pylori (HP) infection has decreased from 49.8% (in 1996) to 31.2% (in 2010). Multivariable logistic regression analyses demonstrated that HP infection was positively associated with GU/DU and negatively associated with RE with statistical significance. The panel data analyses showed that reduced rate of HP infection is proportionally correlated with decrease of GU/DU and inversely correlated with increase of RE. It is further suggested other latent factors should be important for changed prevalence of these three acid-related diseases. Age-period-cohort analysis indicated the significant association of older age, male gender, and absence of HP infection with RE.

CONCLUSIONS

The prevalence of GU and DU has gradually decreased whereas that of RE has markedly increased in Japan. Inverse time trends of peptic ulcer and reflux esophagitis are significantly associated with reduced prevalence of HP infection. KEY MESSAGES The prevalence of gastric and duodenal ulcer has gradually decreased whereas that of reflux esophagitis has markedly increased in Japan. The prevalence of Helicobacter pylori infection in Japan has greatly decreased from 49.8% to 31.2% during the 14 years (from 1996 to 2010). Inverse time trends of peptic ulcer and reflux esophagitis are associated with reduced prevalence of Helicobacter pylori infection with statistical significance.

Towards Personalization in the Curative Treatment of Gastric Cancer

Gastric cancer is the fifth most common cancer worldwide and has a high mortality rate. In the last decades, treatment strategy has shifted from an exclusive surgical approach to a multidisciplinary strategy. Treatment options for patients with resectable gastric cancer as recommended by different worldwide guidelines, include perioperative chemotherapy, pre- or postoperative chemoradiotherapy and postoperative chemotherapy. Although gastric cancer is a heterogeneous disease with respect to patient-, tumor-, and molecular characteristics, the current standard of care is still according to a one-size-fits-all approach. In this review, we discuss the background of the different treatment strategies in resectable gastric cancer including the current standard, the specific role of radiotherapy, and describe the current areas of research and potential strategies for personalization of therapy.

Initial results from a multi-center population-based cluster randomized trial of esophageal and gastric cancer screening in China

Background

We initiated the first multi-center cluster randomized trial of endoscopic screening for esophageal cancer and gastric cancer in China. The objective of the study was to report the baseline screening findings in this trial.

Methods

We recruited a total of 345 eligible clusters from seven screening centers. In the intervention group, participants from high-risk areas were screened by endoscopy; in non-high-risk areas, high-risk individuals were identified using a questionnaire and advised for endoscopy. Lugol’s iodine staining in esophagus and indigo carmine dye in stomach were performed to aid in the diagnosis of suspicious lesions. The primary outcomes of this study were the detection rate (proportion of positive cases among individuals who underwent endoscopic screening) and early detection rate (the proportion of positive cases with stage 0/I among all positive cases).

Results

A total of 149,956 eligible subjects were included. The detection rate was 0.7% in esophagus and 0.8% in stomach, respectively. Compared with non-high-risk areas, the detection rates in high-risk areas were higher, both in esophagus (0.9% vs. 0.1%) and in stomach (0.9% vs. 0.3%). The same difference was found for early-detection rate (esophagus: 92.9% vs. 53.3%; stomach: 81.5% vs. 33.3%).

Conclusions

The diagnostic yield of both esophagus and stomach were higher in high-risk areas than in non-high-risk areas, even though in non-high-risk areas, only high-risk individuals were screened. Our study may provide important clues for evaluating and improving the effectiveness of upper-endoscopic screening in China.

Trial registration: Protocol Registration System in Chinese Clinical Trial Registry, ChiCTR-EOR-16008577. Registered 01 June 2016-Retrospectively registered, http://www.chictr.org.cn/showprojen.aspx?proj=14372

Contribution of chemotherapy to improved prognosis in stage 4 gastric cancer: trend analysis of a regional population-based cancer registry in Japan

OBJECTIVES

Little is known about time trends in the prognosis of gastric cancer (GC), since the introduction of new chemotherapeutic agents. This study aimed to analyze how the increased number of available chemotherapeutic options affected the prognosis of GC and which patient types benefited within in a large population.

METHODS

From a population-based cancer registry in Japan, 35,751 cases of GC were identified. Of these, 8214 cases were stage 4. The time trend for 3-year survival in stage 4 GC according to patient characteristics (age and tumor location) was estimated in relation to the introduction of new anticancer drugs. Multiple imputation was performed for sensitivity analysis to strengthen the missing data. In addition, we estimated the 5-year survival rate for distal-GC (DGC) and proximal-GC (PGC), and the hazard ratio (HR) was estimated by Cox proportional hazard model.

RESULTS

Improvement of overall survival was accelerated in stage 4 cases over time. The prognosis was improved from 11.4% to 13.2%, subsequent to the approval of several oncologic drugs since 2009. Younger patients were more likely to have improved survival rates in response to the increase in chemotherapy options (< 60-year-old, 5.4%: 60-70, 2.2%; 70-80, 0.3%) from 2007 to 2015. The HR for DGC vs. PGC was 1.11 (95% CI 1.08-1.15), and PGC showed a higher rate of improved outcomes (2.4% vs. 0.6%).

CONCLUSIONS

This analysis showed that improvement in the GC survival rate was accelerated by the introduction of new chemotherapeutic strategies and it was most evident among younger patients and in patients with PGC.

Gastrectomy Versus Endoscopic Resection for Patients With Early-stage Gastric Adenocarcinoma: A Population-based Propensity Matching Study

BACKGROUND

This study aimed to compare the long-term results of patients who received these therapies.

MATERIALS AND METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was queried in this research for data of patients with early gastric adenocarcinoma who underwent gastrectomy or endoscopic resection from 2007 to 2015. Propensity score matching was selected to generate a balanced cohort. Competing-risk regression analysis was carried out on the matched cohort. Cancer-specific mortality (CSM) and other cause-specific mortality (OCSM) were compared using adjusted subdistribution hazard ratios (SHRs).

RESULTS

In this study, 2214 patients with 191 underwent endoscopic treatment (ET) and 2023 who underwent surgery were identified. After propensity score matching, 474 patients were included in the analysis. The use of ET increased over time in patients, especially for those with cardia diseases. The ratio of 5-year CSM between ET and gastrectomy groups was 13.12% to 14.24% and the ratio of 5-year OCSM between them was 22.48% versus 14.31%. After adjusting for associated clinicopathologic factors, patients in both groups had similar CSM (SHR=0.87, 95% credible interval: 0.47-1.64, P=0.69) and OCSM (SHR=1.59, 95% credible interval: 0.94-2.68, P=0.08) in multivariable analysis.

CONCLUSION

The long-term prognosis appears equivalent t in patients with endoscopic resection and gastrectomy.

The endoluminal pressures during flexible gastrointestinal endoscopy

In flexible gastrointestinal (GI) endoscopy, endoscopic insufflation is crucial and directly affects visualization. Optimal visualization enables endoscopists to conduct better examinations and administer optimal treatments. However, endoscopic insufflation is typically performed manually and is subjective. We aimed to measure the GI endoluminal pressure during flexible GI endoscopy. Participants underwent esophagogastroduodenoscopy (EGD) at our endoscopy center. Pressure measurement was conducted after completing diagnostic or follow-up EGD. The endoluminal pressure in the esophagus and stomach was measured at 1-s intervals for 1 min while performing EGD for observational and diagnostic purposes. During the measurements, the endoscopists maintained what they subjectively considered to be adequate exposure for screening for lesions by dilating the lumen. Eighty patients were enrolled in this study. The upper GI endoluminal pressure was assessed during EGD without adverse events. The esophageal endoluminal pressure averaged 8.9 (- 3.0 to 20.7) mmHg, and the gastric endoluminal pressure averaged 10.0 (3.0-17.9) mmHg; the upper GI endoluminal pressures were not affected by patient-related factors or the number of endoscopists' postgraduate years. We have successfully obtained the GI endoluminal pressures during EGD. Further accumulation of these data may lead to more stable and reproducible flexible endoscopic diagnosis and intervention.

Protein expression-based classification of gastric cancer by immunohistochemistry of tissue microarray

Recently, the Cancer Genome Atlas and Asian Cancer Research Group propose two new classifications system of gastric cancer by using multi-platforms of molecular analyses. However, these highly complicated and cost technologies have not yet been translated into full clinical utility. In addition, the clinicians are expected to gain more guidance of treatment for different molecular subtypes. In this study, we developed a panel of gastric cancer patients in population from Southern China using commercially accessible TMA and immunohistochemical technology. A cohort of 259 GC patients was classified into 4 subtypes on the basis of expression of mismatch repair proteins (PMS2, MLH1, MSH2, and MSH6), E-cadherin and p21 protein. We observed that the subtypes presented distinct prognosis. dMMR-like subtype was associated with the best prognosis, and E-cadherin-a subtype was associated with the worst prognosis. Patients with p21-High and p21-Ligh subtypes had intermediate overall survival. In multivariate analysis, the dMMR-like subtype remained an independent prediction power for overall survival in the model. We described a molecular classification of gastric cancers using clinically applicable assay. The biological relevance of the four subtypes was illustrated by significant differences in prognosis. Our molecular classification provided an effective and inexpensive screening tool for improving prognostic models. Nevertheless, our study should be considered preliminary and carries a limited predictive value as a single-center retrospective study.

Epidemiology of Gastric Cancer in North Africa and the Middle East from 1990 to 2017

INTRODUCTION

Gastric cancer is the fifth most common cancer worldwide and the third cause of cancer deaths and disability-adjusted life years (DALYs) worldwide. The countries of the Middle East and North Africa are similar in many determinants of health, but there are significant differences in the incidence of gastric cancer in these countries. Therefore, the purpose of this study was to compare the burden of gastric cancer in MENA countries with appropriate policies to reduce the incidence and mortality of gastric cancer in the region.

MATERIALS AND METHODS

GBD database data were used to assess the gastric cancer indices in MENA countries consisted of 21 countries in the Middle East and North Africa in 1900 and 2017. Gastric cancer-related analysis using DALY counts, which is the sum of YLLs (total years lost due to premature death) and YLDs (years lost due to disability), and incidence rates, prevalence rates, death rates, and standardized age rates (ASR) were measured.

RESULTS

The incidence of gastric cancer has decreased in the world and the MENA region from 1990 to 2017, which is higher than the global average in MENA. But death rates in the region have decreased below the global average. The trend of changes in DALY count has increased from 1990 to 2017 in all countries in the region except Turkey. This increase is higher in men than in women and also in Iran. In these countries, the highest percentage of total DALY of gastric cancer is attributable to the risk factors for high sodium and cigarette consumption, in Turkey and the United Arab Emirates, respectively (from 1990 to 2017) Also, the largest decrease is in the UAE and Iraq, respectively.

CONCLUSION

Despite a decrease in the incidence of gastric cancer and, possibly, due to late diagnosis and poor health services, the attenuation of gastric cancer is high in MENA countries. Therefore, it is recommended to reduce the attenuation of screening programs before 50 years old for early detection in addition to prevention programs and to reduce smoking, especially in men.

Curriculum for optical diagnosis training in Europe: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement

This manuscript represents an official Position Statement of the European Society of Gastrointestinal Endoscopy (ESGE) aiming to guide general gastroenterologists to develop and maintain skills in optical diagnosis during endoscopy. In general, this requires additional training beyond the core curriculum currently provided in each country. In this context, ESGE have developed a European core curriculum for optical diagnosis practice across Europe for high quality optical diagnosis training. 1:  ESGE suggests that every endoscopist should have achieved general competence in upper and/or lower gastrointestinal (UGI/LGI) endoscopy before commencing training in optical diagnosis of the UGI/LGI tract, meaning personal experience of at least 300 UGI and/or 300 LGI endoscopies and meeting the ESGE quality measures for UGI/LGI endoscopy. ESGE suggests that every endoscopist should be able and competent to perform UGI/LGI endoscopy with high definition white light combined with virtual and/or dye-based chromoendoscopy before commencing training in optical diagnosis. 2:  ESGE suggests competency in optical diagnosis can be learned by attending a validated optical diagnosis training course based on a validated classification, and self-learning with a minimum number of lesions. If no validated training course is available, optical diagnosis can only be learned by attending a non-validated onsite training course and self-learning with a minimum number of lesions. 3:  ESGE suggests endoscopists are competent in optical diagnosis after meeting the pre-adoption and learning criteria, and meeting competence thresholds by assessing a minimum number of lesions prospectively during real-time endoscopy. ESGE suggests ongoing in vivo practice by endoscopists to maintain competence in optical diagnosis. If a competent endoscopist does not perform in vivo optical diagnosis on a regular basis, ESGE suggests repeating the learning and competence phases to maintain competence.Key areas of interest were optical diagnosis training in Barrett's esophagus, esophageal squamous cell carcinoma, early gastric cancer, diminutive colorectal lesions, early colorectal cancer, and neoplasia in inflammatory bowel disease. Condition-specific recommendations are provided in the main document.

'Four-position method' makes beginner endoscopists aware of spatial positioning of the left hand to master upper gastrointestinal endoscopy

Background and study aims  We developed a novel "four-position method" for facilitating endoscopy of the upper gastrointestinal tract, and this study aimed to verify its usefulness for beginner endoscopists. Methods  Medical students (n = 121) were divided into three groups. A simulator subsequently was used to perform endoscopy. Group A was taught how to hold the endoscope and move the dial; Group B was taught the "four-position method"; and Group C, in addition to being taught the "four-position method," was permitted to use an endoscope before introduction to the simulator. In each group, the transit time to various parts of the upper digestive tract was recorded in addition to the time to grasp a clip in the stomach with the forceps. We also surveyed the groups with respect to their impression of the difficulty level of endoscopic operation before and after instructions. Results  Transit time to the cardia was no different among the groups; however, with regard to other targets, Group C reached the sites significantly more quickly than did Groups A and B. Time to clip grasping was significantly shorter in Groups B and C than in Group A. Regarding the impression of the difficulty level, significantly more students in Groups B and C compared to Group A felt that endoscopy was easier after instructions. Conclusion  Learning the "four-position method" made it possible to achieve stable endoscopic manipulation at an early stage and improve subsequent endoscopic procedures.

Better prognosis of gastric cancer patients with high levels of tumor infiltrating lymphocytes is counteracted by PD-1 expression

The prognostic potential of anti-tumor immune responses is becoming increasingly important in adenocarcinoma of the gastroesophageal junction and stomach (AGE/S) especially regarding the use of immune checkpoint inhibitors. This study analyzes for the first time the prognostic impact of tumor-infiltrating lymphocytes (TILs) and checkpoint inhibitors in a large Caucasian cohort in patients with AGE/S. We screened tissue samples from 438 therapy-naïve patients with AGE/S undergoing surgery between 1992 and 2005, examined in a tissue microarray (TMA) and stained against human CD3, CD4, CD8, PD-1, and PD-L1. Out of 438 tissue samples, 210 were eligible for multivariate analysis. This revealed that high infiltration with CD3+, CD4+, or CD8+ TILs was associated with an increased overall survival in AGE/S patients, which could only be confirmed in multivariate analysis for CD3 (HR: 0.326; p = .023). Independent improved survival was limited to gastric cancer patients and to early tumor stages as long as TILs did not express PD-1 (HR: 1.522; p = .021). Subgroup analyses indicate that TIL-dependent anti-tumor immune response is only effective in gastric cancer patients in early stages of disease in PD-1 negative TILs. Combined analysis of PD-1 and CD3 could serve as a prognostic marker for the clinical outcome of gastric cancer patients and could also be of interest for immunotherapy.

Diagnosis and management of gastric cancer in pregnancy-An evidence-based case report

BACKGROUND

Gastric cancer in pregnancy is a very rare case with an incidence of 0.016% and is mostly detected in a locally advanced or advanced stage due to misinterpretation of non-specific signs and symptoms. Management of gastric cancer in pregnancy should emphasize mother and fetal survival. Currently, there is no diagnostic and management guidance for gastric cancer in pregnancy. The purpose of this study is to ascertain how to diagnose and manage gastric cancer in pregnancy.

METHODS

This study is an evidence-based case report performed in Digestive Division of Department of Surgery in Cipto Mangunkusumo hospital in September-October 2017. Literature search on databases such as Cochrane, PubMed, ScienceDirect, and Scholar Google used keywords like "gastric cancer" AND "pregnant" OR "pregnancy" with inclusion criteria which are systematic review, randomized-clinical trial (RCT), cohort study, case report, or case series, performed in human and published in the last 10 years in English language. Critical appraisal is done according to Oxford Centre For Evidence-Based Medicine 2011. This work is reported in line with the SCARE criteria.

RESULTS

There are 9 case-report studies and 1 case-control study. Radiology examination includes endoscopy, MRI, and CT scan. Management is given according to cancer stage which is; surgery, surgery with adjuvant therapy, and palliative chemotherapy.

CONCLUSION

Radiology examinations with a lower risk of adverse effects are endoscopy and MRI. CT scan may be performed when the benefits exceed the risk. Surgery and chemoradiation have the lowest rate of adverse effects when done in the second and third trimester.

<p>Seroprevalence of <em>Helicobacter pylori</em> Infection and Associated Factors Among Adult Dyspeptic Patients in Public Health Facilities, Mizan Aman Town, Southwest, Ethiopia: Institutional-Based Cross-Sectional Study</p>

Background

Helicobacter pylori infection is a public health problem associated with chronic gastritis, peptic ulcer, and gastric cancer. It is endemic in developing countries like Ethiopia. This study was aimed to assess seroprevalence of H. pylori infection and associated factors among adults’ dyspeptic patients in public health facilities of Mizan Aman Town, Southwest Ethiopia.

Methods

Cross-sectional study was conducted in public health facilities of Mizan Aman Town, from April 1, 2018, to June 30, 2018. A total of 208 adult dyspeptic patients were included in the study. A structured questionnaire was used to collect data. Serum was tested for anti-H. pylori antibody using a commercial test strip. Data were entered using Epi info 6.04 and exported to SPSS 21 for analysis. Bivariate and multivariate logistic regression was employed and OR with 95% CI was retrieved. P-value of less than 0.05 was considered as statistically significant.

Results

A total of 208 participants were interviewed. The mean age of respondents was 31.70 (SD ±9.123) years. Seroprevalence of H. pylori infection was 89 (42.8%). Presence of domestic animals (AOR = 13.33, 95% CI = (2.203–80.692)), sources of drinking water (AOR = 0.011, 95% CI = (0.001–0.110)), toilet type (AOR = 11.236, 95% CI = (1.921–65.73)), shared beds with siblings (AOR = 7.775, 95% CI = (1.676–36.082)), family size (AOR = 0.015, 95% CI = (0.003, 0.089)), storing and reusing water (AOR =0.014, 95% CI = (0.002–0.103)) and occupational status (AOR = 23.33, 95% CI = (2.034–67.661)) were variables significantly associated with seroprevalence of H. pylori.

Conclusion

Seroprevalence of H. pylori infection is relatively high in Ethiopia. Family size, shared bed, presences of domestic animals, storage and reuse of water, toilet type, sources of drinking water, and occupation were significant factors associated with H. pylori infection. The possible identified modifiable risk factors should be addressed through effective health education.

Evaluating the Use of microRNA Blood Tests for Gastric Cancer Screening in a Stratified Population-Level Screening Program: An Early Model-Based Cost-Effectiveness Analysis

OBJECTIVES

To evaluate cost-effectiveness of a novel screening strategy using a microRNA (miRNA) blood test as a screen, followed by endoscopy for diagnosis confirmation in a 3-yearly population screening program for gastric cancer.

METHODS

A Markov cohort model has been developed in Microsoft Excel 2016 for the population identified to be at intermediate risk (Singaporean men, aged 50-75 years with Chinese ethnicity). The interventions compared were (1) initial screening using miRNA test followed by endoscopy for test-positive individuals and a 3-yearly follow-up screening for test-negative individuals (proposed strategy), and (2) no screening with gastric cancer being diagnosed clinically (current practice). The model was evaluated for 25 years with a healthcare perspective and accounted for test characteristics, compliance, disease progression, cancer recurrence, costs, utilities, and mortality. The outcomes measured included incremental cost-effectiveness ratios, cancer stage at diagnosis, and thresholds for significant variables.

RESULTS

The miRNA-based screening was found to be cost-effective with an incremental cost-effectiveness ratio of $40 971/quality-adjusted life-year. Key drivers included test costs, test accuracy, cancer incidence, and recurrence risk. Threshold analysis highlights the need for high accuracy of miRNA tests (threshold sensitivity: 68%; threshold specificity: 77%). A perfect compliance to screening would double the cancer diagnosis in early stages compared to the current practice. Probabilistic sensitivity analysis reported the miRNA-based screening to be cost-effective in >95% of iterations for a willingness to pay of $70 000/quality-adjusted life-year (approximately equivalent to 1 gross domestic product/capita) CONCLUSIONS: The miRNA-based screening intervention was found to be cost-effective and is expected to contribute immensely in early diagnosis of cancer by improving screening compliance.

Impact of examined lymph node count on staging and long-term survival of patients with node-negative stage III gastric cancer: a retrospective study using a Chinese multi-institutional registry with Surveillance, Epidemiology, and End Results (SEER) data validation

BACKGROUND

Accumulating evidence has confirmed the potential prognostic value of examined lymph nodes (ELNs) in patients with gastric cancer (GC). However, there is currently no consensus on the threshold ELN number for predicting both stage migration and long-term survival, especially in patients with stage III GC. This study aimed to validate the need to increase the ELN count to improve its prognostic accuracy in node-negative patients with stage III GC after curative gastrectomy.

METHODS

This retrospective, population-based study analyzed the clinical data of 84 patients with node-negative stage III GC from three high-volume institutions in China and 196 cases from the Surveillance, Epidemiology and End Results (SEER) program registry. The optimal number of ELNs was determined by receiver operating characteristic (ROC) curve analysis. Clinicopathological characteristics significantly related to survival were evaluated using the Kaplan-Meier method and Cox proportional hazards analysis. Stratified analyses were adopted to assess the prognostic predictive ability of the identified optimal number of ELNs in different populations. Survival differences among subgroups were analyzed to assess the impact of ELN count on stage migration according to overall survival (OS) among GC patients.

RESULTS

The optimal number of ELNs was >31 according to ROC analysis of patients with node-negative stage III GC who underwent gastrectomy. Multivariate analysis identified ELNs as an independent predictor of postoperative OS in patients with node-negative stage III GC in both the Chinese cohort [hazard ratio (HR) 0.235; P<0.001] and the SEER cohort (HR 0.421; P<0.010). Stratified analysis demonstrated that >31 ELNs was a prerequisite for accurate prognostic evaluation of patients with node-negative stage III GC, regardless of sex, tumor size, and other factors. Stage migration between pT4bN0M0 and pT4bN1M0 was detected in patients with >31 ELNs. A nomogram was created to predict OS among patients with node-negative stage III GC. These results were validated using data from the SEER cohort.

CONCLUSIONS

The number of ELNs was significantly associated with prognosis in patients with stage III GC after gastrectomy with systemic lymphadenectomy in both the Chinese and SEER cohorts. The results suggest that >31 ELNs are required for an accurate prognostic evaluation in patients with GC, especially those with node-negative stage III GC.

Impacts of age and sedation on cardiocerebrovascular adverse events after diagnostic GI endoscopy: a nationwide population-based study

BACKGROUND AND AIMS

Data are limited regarding the impact of age and sedation on cardiocerebrovascular disease (CCD) adverse events after GI endoscopy. We investigated the incidence of and risk factors for CCD adverse events after diagnostic GI endoscopy and the impact of age and sedation on these unfavorable outcomes.

METHODS

In this nationwide population-based study, the incidence of and risk factors for newly diagnosed CCD within 14 days after diagnostic endoscopy were analyzed using Health Insurance Review and Assessment Service data from January to December 2015.

RESULTS

Among 1,943,150 subjects, CCD adverse events occurred in approximately 2.23% within 14 days after endoscopy. According to the performance of sedation during endoscopy (60.1% nonsedation vs 39.9% sedation, midazolam alone [96.4%]), the incidence rates of CCD adverse events (per 10,000 persons) were 275.8 versus 302.8 for EGD, 116.9 versus 143.8 for colonoscopy, and 230.4 versus 243.2 for EGD + colonoscopy, respectively. On multivariate analysis, older age (70-99 years) and sedation were independent risk factors for CCD adverse events. Regarding CCD risk stratified by age and sedation, older age had a significant impact on CCD adverse events in individuals who underwent EGD only or EGD + colonoscopy, but sedation did not. However, both older age and sedation had considerable influence on CCD adverse events in individuals who underwent colonoscopy only. Sedation during endoscopy was significantly associated with minor but not major CCD adverse events. CCD adverse events were significantly higher for inpatients.

CONCLUSION

CCD adverse events after diagnostic endoscopy were significantly frequent in individuals with older age (70-99 years) and/or sedation during endoscopy. Stratification by age and sedation shows that the impact of these 2 factors on CCD adverse events differs according to endoscopy type.