Effectiveness of the Korean National Cancer Screening Program in Reducing Gastric Cancer Mortality

Global incidence and mortality trends of gastric cancer and predicted mortality of gastric cancer by 2035

OBJECTIVE

To study the historical global incidence and mortality trends of gastric cancer and predicted mortality of gastric cancer by 2035.

METHODS

Incidence data were retrieved from the Cancer Incidence in Five Continents (CI5) volumes I-XI, and mortality data were obtained from the latest update of the World Health Organization (WHO) mortality database. We used join-point regression analysis to examine historical incidence and mortality trends and used the package NORDPRED in R to predict the number of deaths and mortality rates by 2035 by country and sex.

RESULTS

More than 1,089,000 new cases of gastric cancer and 769,000 related deaths were reported in 2020. The average annual percent change (AAPC) in the incidence of gastric cancer from 2003 to 2012 among the male population, South Korea, Japan, Malta, Canada, Cyprus, and Switzerland showed an increasing trend (P > 0.05); among the female population, Canada [AAPC, 1.2; (95%Cl, 0.5-2), P < 0.05] showed an increasing trend; and South Korea, Ecuador, Thailand, and Cyprus showed an increasing trend (P > 0.05). AAPC in the mortality of gastric cancer from 2006 to 2015 among the male population, Thailand [3.5 (95%cl, 1.6-5.4), P < 0.05] showed an increasing trend; Malta Island, New Zealand, Turkey, Switzerland, and Cyprus had an increasing trend (P > 0.05); among the male population aged 20-44, Thailand [AAPC, 3.4; (95%cl, 1.3-5.4), P < 0.05] showed an increasing trend; Norway, New Zealand, The Netherlands, Slovakia, France, Colombia, Lithuania, and the USA showed an increasing trend (P > 0.05). It is predicted that the mortality rate in Slovenia and France's female population will show an increasing trend by 2035. It is predicted that the absolute number of deaths in the Israeli male population and in Chile, France, and Canada female population will increase by 2035.

CONCLUSION

In the past decade, the incidence and mortality of gastric cancer have shown a decreasing trend; however, there are still some countries showing an increasing trend, especially among populations younger than 45 years. Although mortality in most countries is predicted to decline by 2035, the absolute number of deaths due to gastric cancer may further increase due to population growth.

Gastric cancer detection rates using GI endoscopy with serologic risk stratification: a randomized controlled trial

BACKGROUND AND AIMS

Efforts have been made to develop an endoscopic screening system incorporating serologic gastric cancer (GC) risk stratification (ABC classification) alongside annual population-based GC screening using barium. We conducted a randomized controlled trial (RCT) to compare GC detection rates between the Ba-Endo group, which underwent annual barium tests for primary screening followed by detailed endoscopic examinations, and the ABC-Endo group, where endoscopy intervals were determined based on individual gastric cancer risk in the ABC classification.

METHODS

In total, 1206 individuals from Yurihonjo and Nikaho City, Akita Prefecture, were randomized through the minimization method using sex and age as allocation factors. The intervention study was conducted for both groups over 5 years. The Ba-Endo group received annual barium tests, and the ABC-Endo group underwent EGD at different intervals: group A, EGD only at entry; group B, EGD once every 3 years; group C, EGD once every 2 years; and group D, EGD every year.

RESULTS

There were 24 detected GC lesions, with a GC detection rate of 1.9%. GC detection rates in the Ba-Endo and ABC-Endo groups were 2.0% and 1.8%, respectively, with no significant differences between groups (P = 1.0). However, the rate of GC cured by endoscopic resection alone was 41.6% in the Ba-Endo group and was significantly higher at 90.9% in the ABC-Endo group (P = .02).

CONCLUSIONS

There were no differences between the Ba-Endo and ABC-Endo groups in GC detection rates. However, the rate of detected GCs that could be cured by endoscopic resection alone was significantly higher in the ABC-Endo group. (Clinical trial registration number: UMIN000005962.).

Family history and gastric cancer incidence and mortality in Asia: a pooled analysis of more than half a million participants

BACKGROUND

The family history of gastric cancer holds important implications for cancer surveillance and prevention, yet existing evidence predominantly comes from case-control studies. We aimed to investigate the association between family history of gastric cancer and gastric cancer risk overall and by various subtypes in Asians in a prospective study.

METHODS

We included 12 prospective cohorts with 550,508 participants in the Asia Cohort Consortium. Cox proportional hazard regression was used to estimate study-specific adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between family history of gastric cancer and gastric cancer incidence and mortality, then pooled using random-effects meta-analyses. Stratified analyses were performed for the anatomical subsites and histological subtypes.

RESULTS

During the mean follow-up of 15.6 years, 2258 incident gastric cancers and 5194 gastric cancer deaths occurred. The risk of incident gastric cancer was higher in individuals with a family history of gastric cancer (HR 1.44, 95% CI 1.32-1.58), similarly in males (1.44, 1.31-1.59) and females (1.45, 1.23-1.70). Family history of gastric cancer was associated with both cardia (HR 1.26, 95% CI 1.00-1.60) and non-cardia subsites (1.49, 1.35-1.65), and with intestinal- (1.48, 1.30-1.70) and diffuse-type (1.59, 1.35-1.87) gastric cancer incidence. Positive associations were also found for gastric cancer mortality (HR 1.30, 95% CI 1.19-1.41).

CONCLUSIONS

In this largest prospective study to date on family history and gastric cancer, a familial background of gastric cancer increased the risk of gastric cancer in the Asian population. Targeted education, screening, and intervention in these high-risk groups may reduce the burden of gastric cancer.

Optimal number of images and 2-year interval affect cancer detection in screening esophagogastroduodenoscopy: An observational study

We aimed to identify quality indicator for esophagogastroduodenoscopy for detecting upper gastrointestinal (UGI) cancer. Data from 43,526 consecutive health checkups from August 2012 to January 2022 were retrospectively collected. The study ultimately analyzed 42,387 examinations by 12 endoscopists who performed more than 1000 examinations, including all cancers detected. These endoscopists were classified either into fast/slow group based on their mean examination time for a normal finding of esophagogastroduodenoscopy during their first year of the examination, or small/large group based on number of endoscopic images, respectively. The association between UGI cancer detection rate and examination time or the number of images was analyzed, using 5 minutes or 50 images as cutoff values. The detection rate of overall (8 pharyngeal, 39 esophageal, 69 gastric) cancers in the fast, slow, small, and large groups were 0.17%, 0.32%, 0.21%, and 0.31%, respectively. On multivariable analysis, endoscopists in the fast group or the small group were less likely to detect overall UGI cancer (OR: 0.596, 95% CI: 0.373-0.952, P = .030; OR: 0.652, 95% CI: 0.434-0.979, P = .039). Additionally, repeated endoscopy within 2 years had a higher overall cancer detection rate, compared with repeated screening after 2 years. In a sub-analysis, a significant negative relationship was found between the detection rate of gastric cancer and the number of gastric images < 35 (OR: 0.305, 95% CI: 0.189-0.492, P = .000). There was also a negative correlation trend between the detection rate of pharyngeal and esophageal cancers and the number of esophageal images < 11 (OR: 0.395, 95% CI: 0.156-1.001, P = .050). The optimal number of images and screening 2-year interval are considered useful quality indicators for detecting UGI cancer. This study also suggests that a total of 50 images, or 35 images of the stomach are suitable for detecting UGI cancer, or gastric cancer, during screening endoscopy.

A mathematical simulation model to determine the optimal endoscopic screening strategy for detection of H. pylori-naïve gastric neoplasms

BACKGROUND

The effectiveness of esophagogastroduodenoscopy (EGD) screening in cohorts with low Helicobacter pylori prevalence is unknown. This study aimed to develop an optimally efficient EGD screening strategy for detecting H. pylori-naïve gastric neoplasms (HpNGNs).

METHODS

EGD data of 12 institutions from 2016 to 2022 were retrospectively analyzed. Age-related HpNGN prevalence, tumor growth rate, missing rate, and detection threshold size were calculated from the databases. Subsequently, using clinical data, a novel mathematical model that simultaneously simulated demographic changes and HpNGN detection was developed. Screening strategies using different starting ages (40/45/50 years) and intervals (2/5/10 years) were also compared. The detection rates of all tumors occurring within the virtual cohort and number-needed-to-test (NNT) were measured as outcomes.

RESULTS

Data of 519,368 EGDs and 97 HpNGNs (34 pure signet ring cell carcinomas, 26 gastric adenocarcinomas of the fundic gland type, 30 foveolar gastric adenoma-Raspberry type, and seven undifferentiated-type cancer cases) were analyzed. A virtual cohort with a 70-year time horizon was used to simulate the occurrence, growth, and detection of 346,5836 people. Among the strategies with detection rate > 50%, the screening strategy with a 5-year interval starting at 45 years of age had the lowest NNT. Adopting this strategy, most HpNGNs were detected at < 20 mm in size, and the deep submucosal invasion rate was less than 30%.

CONCLUSIONS

A mathematical simulation model revealed that screening every 5 years starting at 45 years of age could efficiently assist in identifying HpNGNs at an early stage.

Culture-based susceptibility-guided tailored versus empirical concomitant therapy as first-line Helicobacter pylori treatment: A randomized clinical trial

BACKGROUND

With the increasing resistance to antimicrobial agents, susceptibility-guided tailored therapy has been emerging as an ideal strategy for Helicobacter pylori treatment. However, susceptibility-guided tailored therapy requires additional cost, time consumption, and invasive procedure (endoscopy) and its superiority over empirical quadruple therapy as the first-line H. pylori treatment remains unclear.

AIMS

To compare the efficacy of culture-based susceptibility-guided tailored versus empirical concomitant therapy as the first-line Helicobacter pylori treatment.

METHODS

This open-label, randomized trial was performed in four Korean institutions. A total of 312 Patients with H. pylori-positive culture test and naïve to treatment were randomly assigned in a 3:1 ratio to either culture-based susceptibility-guided tailored therapy (clarithromycin-based or metronidazole-based triple therapy for susceptible strains or bismuth quadruple therapy for dual-resistant strains, n = 234) or empirical concomitant therapy (n = 78) for 10 days. Eradication success was evaluated by 13C-urea breath test at least 4 weeks after treatment.

RESULTS

Prevalence of dual resistance to both clarithromycin and metronidazole was 8%. H. pylori eradication rates for tailored and concomitant groups were 84.2% and 83.3% by intention-to-treat analysis (p = 0.859), respectively, and 92.9% and 91.5% by per-protocol analysis, respectively (p = 0.702), which were comparable between the two groups. However, eradication rates for dual-resistant strains were significantly higher in the tailored group than in the concomitant group. All adverse events were grade 1 or 2 based on the Common Terminology Criteria for Adverse Events and the incidence was significantly lower in the tailored group. The proportion of patients discontinuing treatment for adverse events was comparable between the two groups (2.1% vs. 2.6%).

CONCLUSIONS

The culture-based susceptibility-guided tailored therapy failed to show superiority over the empirical concomitant therapy in terms of eradication rate. Based on these findings, the treatment choice in clinical practice would depend on the background rate of antimicrobial resistance, availability of resources and costs associated with culture and susceptibility testing.

The Role of Screening and Early Detection in Upper Gastrointestinal Cancers

Upper gastrointestinal cancers are among the leading causes of cancer deaths worldwide with exceptionally poor prognosis, which is largely attributable to frequently delayed diagnosis. Although effective screening is critical for early detection, the highly variable incidence of upper gastrointestinal cancers presents challenges, rendering universal screening programs suboptimal in most populations globally. Optimal strategies in regions of modest incidence, such as the United States, require a targeted approach, focused on high-risk individuals based on demographic, familial, and clinicopathologic risk factors. Assessment of underlying precancerous lesions has key implications for risk stratification and informing clinical decisions to improve patient outcomes.

The diagnostic utility of endocytoscopy for the detection of gastric cancer: a systematic review and meta-analysis

INTRODUCTION

Endocytoscopy (ECS) is an evolving technology that utilizes ultra-high power magnification for real time cellular imaging without the need for physical biopsy. Its application for gastric cancer (GC) detection is not well evaluated at the current time, but there is potential that ECS can make a real time histopathological diagnosis to differentiate neoplastic from benign lesions. We aimed to investigate the diagnostic utility of ECS for GC detection.

EVIDENCE ACQUISITION

Literature searches through multiple databases were performed for studies using ECS for GC detection until November 2021. Measured outcomes included the pooled sensitivity, specificity and accuracy. Quality assessment of diagnostic studies tool was used to assess the risk of bias.

EVIDENCE SYNTHESIS

Four studies (N.=245) were included. The pooled sensitivity was 83.5% (95% CI: 75-89%, I2: 0) and specificity was 91.7% (95% CI: 79-97%, I2: 58%). The pooled accuracy was 89.2% (95% CI: 83-94%, I2: 38%). There was a low risk of bias.

CONCLUSIONS

ECS is an accurate diagnostic modality and has the potential to serve as a complimentary tool in screening for GC. Larger prospective studies are needed to validate these findings before its further widespread use.

Enhanced multi-class pathology lesion detection in gastric neoplasms using deep learning-based approach and validation

This study developed a new convolutional neural network model to detect and classify gastric lesions as malignant, premalignant, and benign. We used 10,181 white-light endoscopy images from 2606 patients in an 8:1:1 ratio. Lesions were categorized as early gastric cancer (EGC), advanced gastric cancer (AGC), gastric dysplasia, benign gastric ulcer (BGU), benign polyp, and benign erosion. We assessed the lesion detection and classification model using six-class, cancer versus non-cancer, and neoplasm versus non-neoplasm categories, as well as T-stage estimation in cancer lesions (T1, T2-T4). The lesion detection rate was 95.22% (219/230 patients) on a per-patient basis: 100% for EGC, 97.22% for AGC, 96.49% for dysplasia, 75.00% for BGU, 97.22% for benign polyps, and 80.49% for benign erosion. The six-class category exhibited an accuracy of 73.43%, sensitivity of 80.90%, specificity of 83.32%, positive predictive value (PPV) of 73.68%, and negative predictive value (NPV) of 88.53%. The sensitivity and NPV were 78.62% and 88.57% for the cancer versus non-cancer category, and 83.26% and 89.80% for the neoplasm versus non-neoplasm category, respectively. The T stage estimation model achieved an accuracy of 85.17%, sensitivity of 88.68%, specificity of 79.81%, PPV of 87.04%, and NPV of 82.18%. The novel CNN-based model remarkably detected and classified malignant, premalignant, and benign gastric lesions and accurately estimated gastric cancer T-stages.

Stomach Cancer Prediction Model (SCoPM): An approach to risk stratification in a diverse U.S. population

BACKGROUND AND AIMS

Population-based screening for gastric cancer (GC) in low prevalence nations is not recommended. The objective of this study was to develop a risk-prediction model to identify high-risk patients who could potentially benefit from targeted screening in a racial/ethnically diverse regional US population.

METHODS

We performed a retrospective cohort study from Kaiser Permanente Southern California from January 2008-June 2018 among individuals age ≥50 years. Patients with prior GC or follow-up <30 days were excluded. Censoring occurred at GC, death, age 85 years, disenrollment, end of 5-year follow-up, or study conclusion. Cross-validated LASSO regression models were developed to identify the strongest of 20 candidate predictors (clinical, demographic, and laboratory parameters). Records from 12 of the medical service areas were used for training/initial validation while records from a separate medical service area were used for testing.

RESULTS

1,844,643 individuals formed the study cohort (1,555,392 training and validation, 289,251 testing). Mean age was 61.9 years with 53.3% female. GC incidence was 2.1 (95% CI 2.0-2.2) cases per 10,000 person-years (pyr). Higher incidence was seen with family history: 4.8/10,000 pyr, history of gastric ulcer: 5.3/10,000 pyr, H. pylori: 3.6/10,000 pyr and anemia: 5.3/10,000 pyr. The final model included age, gender, race/ethnicity, smoking, proton-pump inhibitor, family history of gastric cancer, history of gastric ulcer, H. pylori infection, and baseline hemoglobin. The means and standard deviations (SD) of c-index in validation and testing datasets were 0.75 (SD 0.03) and 0.76 (SD 0.02), respectively.

CONCLUSIONS

This prediction model may serve as an aid for pre-endoscopic assessment of GC risk for identification of a high-risk population that could benefit from targeted screening.

Hotspots and trends of risk factors in gastric cancer: A visualization and bibliometric analysis

BACKGROUND

The lack of specific symptoms of gastric cancer (GC) causes great challenges in its early diagnosis. Thus it is essential to identify the risk factors for early diagnosis and treatment of GC and to improve the survival rates.

AIM

To assist physicians in identifying changes in the output of publications and research hotspots related to risk factors for GC, constructing a list of key risk factors, and providing a reference for early identification of patients at high risk for GC.

METHODS

Research articles on risk factors for GC were searched in the Web of Science core collection, and relevant information was extracted after screening. The literature was analyzed using Microsoft Excel 2019, CiteSpace V, and VOSviewer 1.6.18.

RESULTS

A total of 2514 papers from 72 countries and 2507 research institutions were retrieved. China (n = 1061), National Cancer Center (n = 138), and Shoichiro Tsugane (n = 36) were the most productive country, institution, or author, respectively. The research hotspots in the study of risk factors for GC are summarized in four areas, namely: Helicobacter pylori (H. pylori) infection, single nucleotide polymorphism, bio-diagnostic markers, and GC risk prediction models.

CONCLUSION

In this study, we found that H. pylori infection is the most significant risk factor for GC; single-nucleotide polymorphism (SNP) is the most dominant genetic factor for GC; bio-diagnostic markers are the most promising diagnostic modality for GC. GC risk prediction models are the latest current research hotspot. We conclude that the most important risk factors for the development of GC are H. pylori infection, SNP, smoking, diet, and alcohol.

Evaluation of the value of combined detection of tumor markers CA724, carcinoembryonic antigen, CA242, and CA19-9 in gastric cancer

BACKGROUND

Gastric cancer is a global health concern that poses a significant threat to human well-being.

AIM

To detecting serum changes in carcinoembryonic antigen (CEA), carbohydrate antigens (CA) 724, CA242, and CA19-9 expression among patients with gastric cancer.

METHODS

Eighty patients diagnosed with gastric cancer between January 2020 and January 2023 were included in the observation group, while 80 patients with benign gastric diseases were included in the control group. Both groups were tested for tumor markers (CA724, CEA, CA242, and CA19-9]. Tumor marker indicators (CA724, CEA, CA242, and CA19-9) were compared between the two groups, assessing positive rates of tumor markers across various stages in the observation group. Additionally, single and combined detection of various tumor markers were examined.

RESULTS

The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value observed for the combined detection of CA724, CEA, CA242, and CA19-9 were higher than those of CA724, CEA, CA242, and CA19-9 individually. Therefore, the combined detection of CA724, CEA, CA242, and CA19-9 has a high diagnostic accuracy and could reduce the occurrence of missed or misdiagnosed cases, facilitating the early diagnosis and treatment of patients.

CONCLUSION

CA724, CEA, CA242, and CA19-9 serum levels in gastric cancer patients significantly surpassed those in non-gastric cancer patients (P < 0.05). Their combined detection can improve the diagnostic accuracy for gastric cancer, warranting clinical promotion.

Efficacy and safety of three-dimensional magnetically assisted capsule endoscopy for upper gastrointestinal and small bowel examination

BACKGROUND

Magnetically assisted capsule endoscopy (MACE) showed the feasibility for upper gastrointestinal examination. To further enhance the performance of conventional MACE, it is necessary to provide quality-improved and three-dimensional images. The aim of this clinical study was to determine the efficacy and safety of novel three-dimensional MACE (3D MACE) for upper gastrointestinal and small bowel examination at once.

METHODS

This was a prospective, single-center, non-randomized, and sequential examination study (KCT0007114) at Dongguk University Ilsan Hospital. Adult patients who visited for upper endoscopy were included. The study protocol was conducted in two stages. First, upper gastrointestinal examination was performed using 3D MACE, and a continuous small bowel examination was performed by conventional method of capsule endoscopy. Two hours later, an upper endoscopy was performed for comparison with 3D MACE examination. The primary outcome was confirmation of major gastric structures (esophagogastric junction, cardia/fundus, body, angle, antrum, and pylorus). Secondary outcomes were confirmation of esophagus and duodenal bulb, accuracy for gastric lesions, completion of small bowel examination, 3D image reconstruction of gastric lesion, and safety.

RESULTS

Fifty-five patients were finally enrolled. The examination time of 3D MACE was 14.84 ± 3.02 minutes and upper endoscopy was 5.22 ± 2.39 minutes. The confirmation rate of the six major gastric structures was 98.6% in 3D MACE and 100% in upper endoscopy. Gastric lesions were identified in 43 patients during 3D MACE, and 40 patients during upper endoscopy (Sensitivity 0.97). 3D reconstructed images were acquired for all lesions inspected by 3D MACE. The continuous small bowel examination by 3D MACE was completed in 94.5%. 3D MACE showed better overall satisfaction (3D MACE 9.55 ± 0.79 and upper endoscopy 7.75 ± 2.34, p<0.0001). There were no aspiration or significant adverse event or capsule retention in the 3D MACE examination.

CONCLUSIONS

Novel 3D MACE system is more advanced diagnostic modality than the conventional MACE. And it is possible to perform serial upper gastrointestinal and small bowel examination as a non-invasive and one-step test. It would be also served as a bridge to pan-endoscopy.

Barriers to upper gastrointestinal screening among the general population in high-prevalence areas: a cross-sectional study

BACKGROUND

In China, there are large differences between regions in the use of gastroscopies and public awareness of upper gastrointestinal (UGI) screening.

OBJECTIVE

This study investigated the current context and analyzed the barriers that influence UGI screening behavior among the general population in UGI cancer high-prevalence areas.

METHODS

A total of 320 participants anonymously answered an online questionnaire. The rank sum test was used to analyze the difference in the scores of the UGI screening awareness questionnaire among participants with different socio-demographic characteristics. Using the awareness level of UGI screening and gastroscopy as the dependent variable, and the socio-demographic characteristics as the independent variable, simple linear regression and binary logistic regression analysis were used to determine the factors influencing attitudes toward gastroscopy screening. We used Spearman's correlation analysis to examine the correlation between UGI screening awareness level and willingness to undergo a gastroscopy.

RESULTS

There was a correlation between the willingness to undergo gastroscopy and the awareness level of UGI screening (r = 0.243, p < 0.001). Linear regression analysis found that age, type of residence, education level, employment status, monthly income, history of gastroscopy, dietary habits, physical exercise, and convenience in obtaining information were significantly correlated with the awareness level of UGI screening ( p < 0.05). Binary logistic regression analysis found that factors significantly associated with gastric cancer screening behavior include residence, monthly income, and self-perceived health status ( p  < 0.05).

CONCLUSION

It is necessary to improve education about UGI cancer and screening knowledge, with a focus on populations with lower education and income.

Efficacy evaluation of upper gastrointestinal endoscopy screening for secondary prevention of gastric cancer using the standardized detection ratio during a medical check-up in Japan

We used standardized detection ratio to evaluate the quality of nasal upper gastrointestinal endoscopy screening for the secondary prevention of gastric cancer, and examined the gastric cancer risk in the era of total Helicobacter pylori (H. pylori) eradication. We performed 21,931 upper gastrointestinal endoscopies, 77 subjects were diagnosed with gastric cancer. Of these, 28 had gastric cancer after H. pylori eradication, 47 had gastric cancer with H. pylori-positive or others, and 2 had H. pylori-negative gastric cancer. The Standardized detection ratios for men and women were 5.33 and 4.82, respectively. Multivariable logistic regression analyses performed exclusively on first endoscopy subjects, excluding H. pylori-negative gastric cancer, revealed that smoking was a risk factor for developing gastric cancer (adjusted odds ratio, 3.31; 95% confidence interval, 1.65-6.64; p = 0.001). A statistically significant interaction was found between daily alcohol consumpption and H. pylori eradication on gastric cancer development (p = 0.005). In conclusion, relatively high standardized detection ratio values suggest that an appropriate endoscopic diagnosis of gastric cancer should be performed during a medical check-up. Smoking is a risk factor for developing gastric cancer, and continued alcohol consumption suggests a possible risk for developing gastric cancer after H. pylori eradication.

Population-level cancer screening and cancer care in Bhutan, 2020-2023: a review

Screening of cancers is an important intervention in reducing the incidence and mortality related to cancers. Bhutan is one small country that is witnessing an increasing incidence and mortality related to cancers. The government implemented a time-bound population-level screening for gastric, cervical and breast cancers from 2020 to 2023 with an overall coverage of 91.2% of the eligible population. Among 370,225 individuals screened for H pylori, 32.4% tested positive; among 53,182 who underwent upper gastrointestinal endoscopy and biopsy, 255 (0.07%) had gastric cancer. Among 10,749 tested for HPV DNA, 9.3% were positive; among 9887 evaluated with colposcopy and biopsy, 154 (0.13%) had cervical cancer. For breast cancer screening, 72,283 underwent clinical breast examination, 845 mammography and cancer was detected in 73 (0.10%) individuals. In this article, we review how Bhutan implemented a population-level cancer screening programme with on boarding of multiple stakeholders and the participation of people across all districts.

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

BACKGROUNDS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Preservation of the celiac branch of the vagus nerve reduces the incidence of postoperative diarrhea in gastric cancer: a cohort study

BACKGROUND

To investigate the short-term and long-term outcomes of preserving the celiac branch of the vagus nerve during laparoscopic distal gastrectomy.

METHODS

A total of 149 patients with prospective diagnosis of gastric cancer who underwent laparoscopic-assisted distal gastrectomy (LADG) combined with Billroth-II anastomosis and D2 lymph node dissection between 2017 and 2018 were retrospectively analyzed. The patients were divided into the preserved LADG group (P-LADG, n = 56) and the resected LADG group (R-LADG, n = 93) according to whether the vagus nerve celiac branch was preserved. We selected 56 patients (P-LADG, n = 56) with preservation of the celiac branch of the vagus nerve and 56 patients (R-LADG, n = 56) with removal of the celiac branch of the vagus nerve by propensity-matched score method. Postoperative nutritional status, weight change, short-term and long-term postoperative complications, and gallstone formation were evaluated in both groups at 5 years of postoperative follow-up. The status of residual gastritis and bile reflux was assessed endoscopically at 12 months postoperatively.

RESULTS

The incidence of diarrhea at 5 years postoperatively was lower in the P-LADG group than in the R-LADG group (p < 0.05). In the multivariate logistic analysis, the removal of vagus nerve celiac branch was an independent risk factor for the occurrence of postoperative diarrhea (odds ratio = 3.389, 95% confidential interval = 1.143-10.049, p = 0.028). In the multivariate logistic analysis, the removal of vagus nerve celiac branch was an independent risk factor for the occurrence of postoperative diarrhea (odds ratio = 4.371, 95% confidential interval = 1.418-13.479, p = 0.010).

CONCLUSIONS

Preservation of the celiac branch of the vagus nerve in LADG reduced the incidence of postoperative diarrhea postoperatively in gastric cancer.

TRIAL REGISTRATION

This study was registered with the Ethics Committee of the First Affiliated Hospital of Dalian Medical University in 2014 under the registration number: LCKY2014-04(X).

Population effectiveness of endoscopy screening for mortality reduction in gastric cancer

Objectives

No randomized controlled trials have compared endoscopic screening with no screening for gastric cancer on an intention-to-screen basis, and the population-based evidence is insufficient. This study aimed to identify factors contributing to the population effectiveness of cancer screening, estimate the number needed to screen (NNS) to reduce one gastric cancer-related death, and evaluate the expected mortality-rate reduction in endoscopic screening for gastric cancer in 184 countries.

Methods

Factors contributing to the attributable risk, NNS, and mortality-rate reduction were identified. A rapid review was performed in PubMed to estimate the pooled relative risk of endoscopic screening compared to that of no screening for mortality reduction. NNSs and mortality-rate reduction were estimated using the pooled relative risk and GLOBOCAN data.

Results

The crude mortality rate, the effectiveness of the screening modality, and the screened rate contributed to the attributable risk, NNS, and mortality-rate reduction in cancer screening. The pooled relative risk was 0.58 in endoscopy screening compared to that in no screening. NNSs and expected mortality-rate reduction differed across countries and ranged from 2522 to 91,575 and 0.2 to 7.9 (per 100,000 individuals) for the screened rate of 20%, respectively.

Conclusions

In addition to the effectiveness of the used modality, the disease burden and screened rate were important in the population effectiveness of cancer screening. Regarding the high NNSs and the low expected mortality-rate reduction, population-based endoscopic screening seems not to be effective in many countries, and these results are meaningful in decision-making regarding the introduction of endoscopic screening.

Cost-effectiveness analysis of the artificial intelligence diagnosis support system for early gastric cancers

Objectives

The introduction of artificial intelligence into the medical field has improved the diagnostic capabilities of physicians. However, few studies have analyzed the economic impact of employing artificial intelligence technologies in the clinical environment. This study evaluated the cost-effectiveness of a computer-assisted diagnosis (CADx) system designed to support clinicians in differentiating early gastric cancers from non-cancerous lesions in Japan, where the universal health insurance system was introduced.

Methods

The target population to be used for the CADx was estimated as those with moderate to severe gastritis caused by Helicobacter pylori infection. Decision trees with Markov models were built to analyze the cumulative cost-effectiveness of using CADx relative to the pre-artificial intelligence status quo, a condition reconstructed from data in published reports. After conducting a base-case analysis, we performed sensitivity analyses by modifying several parameters. The primary outcome was the incremental cost-effectiveness ratio.

Results

Compared with the status quo as represented in the base-case analysis, the incremental cost-effectiveness ratio of CADx in the Japanese market was forecasted to be 11,093 USD per quality-adjusted life year. The sensitivity analyses demonstrated that the expected incremental cost-effectiveness ratios were within the willingness-to-pay threshold of 50,000 USD per quality-adjusted life year when the cost of the CAD was less than 104 USD.

Conclusions

Using CADx for EGCs may decrease their misdiagnosis, contributing to improved cost-effectiveness in Japan.

Liquid biopsy for gastric cancer: Techniques, applications, and future directions

After the study of circulating tumor cells in blood through liquid biopsy (LB), this technique has evolved to encompass the analysis of multiple materials originating from the tumor, such as nucleic acids, extracellular vesicles, tumor-educated platelets, and other metabolites. Additionally, research has extended to include the examination of samples other than blood or plasma, such as saliva, gastric juice, urine, or stool. LB techniques are diverse, intricate, and variable. They must be highly sensitive, and pre-analytical, patient, and tumor-related factors significantly influence the detection threshold, diagnostic method selection, and potential results. Consequently, the implementation of LB in clinical practice still faces several challenges. The potential applications of LB range from early cancer detection to guiding targeted therapy or immunotherapy in both early and advanced cancer cases, monitoring treatment response, early identification of relapses, or assessing patient risk. On the other hand, gastric cancer (GC) is a disease often diagnosed at advanced stages. Despite recent advances in molecular understanding, the currently available treatment options have not substantially improved the prognosis for many of these patients. The application of LB in GC could be highly valuable as a non-invasive method for early diagnosis and for enhancing the management and outcomes of these patients. In this comprehensive review, from a pathologist's perspective, we provide an overview of the main options available in LB, delve into the fundamental principles of the most studied techniques, explore the potential utility of LB application in the context of GC, and address the obstacles that need to be overcome in the future to make this innovative technique a game-changer in cancer diagnosis and treatment within clinical practice.

Prevalence of Gastric Precursor Lesions in Countries With Differential Gastric Cancer Burden: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

The prevalence of precursor lesions for gastric cancer (GC) and the differential burden between countries of varying GC risk is not well-understood. We conducted a systematic review and meta-analysis to estimate the global prevalence of precursor lesions.

METHODS

We estimated the prevalence of atrophic gastritis (AG), gastric intestinal metaplasia (IM), and dysplasia in regions with low, medium, and high GC incidence. Because IM is an advanced manifestation of AG, we assessed the prevalence of less advanced precursors, regardless of the presence of more advanced lesions. Prevalence was sub-stratified by Helicobacter pylori infection, symptomatology, and period (<2000, 2000-2010, and >2010).

RESULTS

Among the 582 articles that underwent full-text review, 166 studies met inclusion criteria. The global prevalence estimates of AG, IM, and dysplasia were 25.4%, 16.2%, and 2.0%, respectively, on the basis of 126 studies that reported the prevalence of less advanced precursors, regardless of the presence of more advanced lesions. The prevalence of all precursor lesions was higher in high and medium compared with low GC incidence countries (P < .01). Prevalence of AG and IM was significantly higher among H pylori-infected individuals (P < .01) but not statistically different between symptomatic and asymptomatic individuals (P > .17). All precursors demonstrated a secular decrease in prevalence over time.

CONCLUSIONS

Gastric precursor lesions have differences in prevalence in regions with differential GC incidence and are associated with H pylori infection. Because of the substantial prevalence of precursor lesions in both symptomatic and asymptomatic individuals, symptomatic evaluation may not be sufficient to identify individuals at risk. These estimates provide important insights for tailoring GC prevention strategies.

The Effect of Nationwide Organized Cancer Screening Programs on Gastric Cancer Mortality: A Synthetic Control Study

BACKGROUND & AIMS

Nationwide organized gastric cancer (GC) screening programs have been running for decades in South Korea and Japan. This study conducted a quasi-experimental analysis to assess the population impact of these programs on GC mortality.

METHODS

We used the flexible synthetic control method (SCM) to estimate the effect of the screening programs on age-standardized GC mortality and other upper gastrointestinal (UGI) diseases (esophageal cancer and peptic ulcer) among people aged ≥40 years. World Health Organization mortality data and country-level covariates from the World Bank and the Global Burden of Diseases study were used for the analyses. We compared postintervention trends in outcome with the counterfactual trend of the synthetic control and estimated average postintervention rate ratios (RRs) with associated 95% confidence intervals (CIs). A series of sensitivity analyses were conducted.

RESULTS

The preintervention fits were acceptable for the analyses of South Korea and Japan's GC mortality but poor for Japan's other UGI disease mortality. The average postintervention RRs were 0.83 (95% CI, 0.71-0.96) for GC mortality and 0.72 (95% CI, 0.57-0.90) for other UGI disease mortality in South Korea. The RR reached 0.59 by the 15th year after the initiation of nationwide screening. For Japan, the average RRs were 0.97 (95% CI, 0.88-1.07) for GC mortality and 0.93 (95% CI, 0.68-1.28) for other UGI disease mortality. Sensitivity analysis reveals the result for Japan may potentially be biased.

CONCLUSIONS

South Korea's nationwide GC screening has apparent benefits, whereas the Japanese program's effectiveness is uncertain. The experiences of South Korea and Japan could serve as a reference for other countries.

Association of Primary Care Physician Supply with Population Mortality in South Korea: A Pooled Cross-Sectional Analysis

BACKGROUND

Primary care physicians perform a comprehensive role by providing continuous, patient-centered, and accessible healthcare and establishing connections with specialized care. However, the association between the supply of primary care physicians and mortality rates in South Korea has not been thoroughly investigated.

METHODS

This study utilized data from 229 si-gun-gu in South Korea from 2016 to 2020. The densities of primary care physicians, physicians in functional primary clinics, specialists in primary care facilities, and active physicians per 100,000 people were independent variables. Age-adjusted all-cause mortality and cause-specific mortality rates per 100,000 individuals were the dependent variables. Negative binomial regression, negative binomial regression with a pseudo-panel approach, and geographically weighted regression were used to analyze the data.

RESULTS

Our study revealed a significant negative association between the density of primary care physicians and all-cause mortality. An increase in a primary care physician per 100,000 population was significantly linked to a 0.11% reduction in all-cause mortality (incidence rate ratio, 0.9989; 95% confidence interval, 0.9983-0.9995). Similar associations have been observed between mortality rates owing to cardiovascular diseases, respiratory tract diseases, and traffic accidents.

CONCLUSION

This study provides evidence that having a higher number of primary care physicians in South Korea is associated with lower mortality rates. Future research should consider better indicators that reflect the quality of primary care to better understand its impact on population health outcomes. These findings emphasize the significance of strengthening primary care in the South Korean healthcare system to improve the overall health and wellbeing.

Editorial article to: Animal experimental study on magnetic anchor technique-assisted endoscopic submucosal dissection of early gastric cancer

In this editorial we comment on the article published in the recent issue of the World Journal of Gastrointestinal Endoscopy 2023; 15 (11): 634-680. Gastric cancer (GC) remains the fifth most common malignancy and the fourth leading cause of cancer-related death worldwide. The overall prevalence of GC has declined, although that of proximal GC has increased over time. Thus, a significant proportion of GC cases and deaths can be avoided if preventive interventions are taken. Early GC (EGC) is defined as GC confined to the mucosa or submucosa. Endoscopic resection is considered the most appropriate treatment for precancerous gastrointestinal lesions improving patient quality of life, with reduced rates of complications, shorter hospitalization period, and lower costs when compared to surgical resection. Endoscopic mucosal resection (EMR) and endoscopic sub-mucosal dissection (ESD) are representative endoscopic treatments for EGC and precancerous gastric lesions. Standard EMR implies injection of a saline solution into the sub-mucosal space, followed by excision of the lesion using a snare. Complete resection rates vary depending on the size and severity of the lesion. When using conventional EMR methods for lesions less than 1 cm in size, the complete resection rate is approximately 60%, whereas for lesions larger than 2 cm, the complete resection rate is low (20%-30%). ESD can be used to remove tumors exceeding 2 cm in diameter and lesions associated with ulcers or submucosal fibrosis. Compared with EMR, ESD has higher en bloc resection rates (90.2% vs 51.7%), higher complete resection rates (82.1 vs 42.2%), and lower recurrence rates (0.65% vs 6.05%). Thus, innovative techniques have been introduced.

Age- and cause-specific contributions to increase in life expectancy at birth in Korea, 2000-2019: a descriptive study

BACKGROUND

Korea's life expectancy at birth has consistently increased in the 21st century. This study compared the age and cause-specific contribution to the increase in life expectancy at birth in Korea before and after 2010.

METHODS

The population and death numbers by year, sex, 5-year age group, and cause of death from 2000 to 2019 were acquired. Life expectancy at birth was calculated using an abridged life table by sex and year. The annual age-standardized and age-specific mortality by cause of death was also estimated. Lastly, the age and cause-specific contribution to the increase in life expectancy at birth in the two periods were compared using a stepwise replacement algorithm.

RESULTS

Life expectancy at birth in Korea increased consistently from 2010 to 2019, though slightly slower than from 2000 to 2009. The cause-specific mortality and life expectancy decomposition analysis showed a significant decrease in mortality in chronic diseases, such as neoplasms and diseases of the circulatory system, in the middle and old-aged groups. External causes, such as transport injuries and suicide, mortality in younger age groups also increased life expectancy. However, mortality from diseases of the respiratory system increased in the very old age group during 2010-2019.

CONCLUSIONS

Life expectancy at birth in Korea continued to increase mainly due to decreased mortality from chronic diseases and external causes during the study period. However, the aging of the population structure increased vulnerability to respiratory diseases. The factors behind the higher death rate from respiratory disease should be studied in the future.

Enantiomer-Specific Colorimetric Tandem Assays for Salivary d-Alanine Associated with Gastric Cancer

Salivary d-alanine (d-Ala) and d-proline (d-Pro) are of concern for their potential in the noninvasive diagnosis of gastric cancer (GC). Most reports have succeeded in determining the total concentration of d-Ala and d-Pro. However, for personalized diagnosis and better elucidation of the underlying specific correlation of d-Ala (or d-Pro) with GC, it is desirable to determine the specific concentration of d-Ala or d-Pro. Herein, we propose an enantiomer-specific tandem assay of d-Ala based on the colorimetric reaction between 2,4-dinitrophenylhydrazine and pyruvic acid generated from the deamination of d-Ala catalyzed by d-amino acid oxidase, which is easily distinguished from l-form amino acids, d-Pro, and many other species. A linear concentration range is established from 20 to 400 μmol/L with a limit of detection of 1.01 μmol/L. Real saliva sample tests reveal that the levels of d-Ala in GC cases are remarkably higher than those in healthy individuals, which offers a simple and low-cost strategy for GC diagnosis. Simultaneously, the total concentrations of d-Ala and d-Pro in saliva are determined. Hence, the concentration of d-Pro and the proportion of d-Ala could be calculated, which further provides more molecule- and individual-specific information. This research may offer a convenient method for noninvasive diagnosis of GC and pave a new route to explore the potentials of rare d-form amino acids in disease diagnosis and treatment.

Gastric cancer specific drug delivery with hydrophilic peptide probe conjugation

Cancer-specific diagnosis is challenging. Phage display is an approach that could contribute to finding new specific biomarkers. In this study, we developed a new peptide probe specific for gastric cancer and validated it for gastric cancer-specific theranostics. We isolated linear peptides by screening a combinatorial phage library for a cancer stem cell marker, LGR5 protein. Among these, peptides with high selectivity against gastric cancer cells were selected and examined for therapeutic poteintial in vitro as well as in vivo. Through leucine-rich G protein-coupled receptor 5 (LGR5) protein-based phage display, we obtained a hydrophilic 7-mer peptide sequence (STCTRSR, named STC). Both the STC-peptide-conjugated fluorescent dye and chlorin e6 (Ce6) displayed a significantly higher intensity in gastric cancer cells compared to that in healthy cells. In mice with gastric cancer, the fluorescence in the tumors was 3.4× more intense when treated with the Ce6-STC conjugate compared to that with free Ce6 and conferred higher phototoxicity after single laser irradiation. Repeated photodynamic therapy could further reduce the tumor volume after treating these mice with the Ce6-STC conjugate. The treatment with the Ce6-STC conjugate exhibited a significantly lower fluorescence in the liver than that with free Ce6. In conclusion, we confirmed that the STC peptide is a gastric cancer-specific probe that could be useful in gastric cancer theranostics. In conclusion, considering its targeting ability and hydrophilicity, various hydrophobic chemotherapeutic agents could be revisited for gastric cancer treatment in combination with the probe described in this study.

Inhibition of TAF1B impairs ribosome biosynthesis and suppresses cell proliferation in stomach adenocarcinoma through promoting c-MYC mRNA degradation

Hyperactivation of ribosome biosynthesis (RiBi) is a hallmark of cancer, and targeting ribosome biogenesis has emerged as a potential therapeutic strategy. The depletion of TAF1B, a major component of selectivity factor 1 (SL1), disrupts the pre-initiation complex, preventing RNA polymerase I from binding ribosomal DNA and inhibiting the hyperactivation of RiBi. Here, we investigate the role of TAF1B, in regulating RiBi and proliferation in stomach adenocarcinoma (STAD). We disclosed that the overexpression of TAF1B correlates with poor prognosis in STAD, and found that knocking down TAF1B effectively inhibits STAD cell proliferation and survival in vitro and in vivo. TAF1B knockdown may also induce nucleolar stress, and promote c-MYC degradation in STAD cells. Furthermore, we demonstrate that TAF1B depletion impairs rRNA gene transcription and processing, leading to reduced ribosome biogenesis. Collectively, our findings suggest that TAF1B may serve as a potential therapeutic target for STAD and highlight the importance of RiBi in cancer progression.

Precision endoscopy in the era of climate change and sustainability

Global warming caused by increased greenhouse gas (GHG) emissions has a direct impact on human health. Gastrointestinal (GI) endoscopy contributes significantly to GHG emissions due to energy consumption, reprocessing of endoscopes and accessories, production of equipment, safe disposal of biohazardous waste, and travel by patients. Moreover, GHGs are also generated in histopathology through tissue processing and the production of biopsy specimen bottles. The reduction in unnecessary surveillance endoscopies and biopsies is a practical approach to decrease GHG emissions without affecting disease outcomes. This narrative review explores the role of precision medicine in GI endoscopy, such as image-enhanced endoscopy and artificial intelligence, with a focus on decreasing unnecessary endoscopic procedures and biopsies in the surveillance and diagnosis of premalignant lesions in the esophagus, stomach, and colon. This review offers strategies to minimize unnecessary endoscopic procedures and biopsies, decrease GHG emissions, and maintain high-quality patient care, thereby contributing to sustainable healthcare practices.

Global burden of stomach cancer attributable to smoking from 1990 to 2019 and predictions to 2044

OBJECTIVES

This study aimed to assess the global temporal trends of stomach cancer attributable to smoking from 1990 to 2019 and to predict the global burden by 2044.

STUDY DESIGN

This was a comprehensive analysis based on data provided by the Global Burden of Disease Study 2019.

METHODS

Based on the Global Burden of Disease Study 2019, mortality, disability-adjusted life years (DALYs), and corresponding age-standardised rates of stomach cancer attributable to smoking by sociodemographic index (SDI), region, country, sex, and age were used to assess temporal trends from 1990 to 2019 by calculating the average annual percentage change (AAPC). In addition, the global burden of stomach cancer attributable to smoking up to 2044 was predicted using age-period-cohort models.

RESULTS

Globally, in 2019, 17.96% of stomach cancer deaths (1.72 million) and 17.15% of stomach cancer DALYs (38.13 million) were attributable to smoking, representing an increase compared to 1990; however, smoking-attributable age-standardised rates of mortality (ASMRs) and DALYs (ASDRs) significantly declined to 2.12/100,000 and 45.82/100,000 in 2019, respectively. While stomach cancer ASMR and ASDR attributable to smoking decreased in all regions and in most countries, they increased by >10% in some countries. A positive correlation was found between SDI and age-standardised rates (rASMR = 0.28, P < 0.01; rASDR = 0.29, P < 0.01). By 2044, although global age-standardised rates for smoking-attributable stomach cancer are predicted to decline, deaths and DALYs are estimated to increase to 2.22 million and 42.14 million, respectively.

CONCLUSIONS

Stomach cancer deaths and DALYs attributable to smoking have increased over the past 30 years and will continue to increase. Consequently, targeted prevention efforts and tobacco-control strategies need to be further developed and improved.

The Operative Link on Gastritis Assessment (OLGA) system as a marker for gastric cancer and dysplasia in a Colombian population at risk: A multicenter study

Introduction. The OLGA system has been proved to be useful in Asia and Europe as a risk marker of gastric cancer. However, its usefulness in high-risk populations in Colombia is still unknown. Objective. To assess potential associations between the OLGA staging system and an increased risk of gastric cancer and dysplasia in a high-risk Colombian population and to establish diagnostic capacity of the scale to assess the risk. Materials and methods. We carried out a multicenter study including patients with cancer and dysplasia (cases) and patients with atrophy and intestinal metaplasia (controls). A total of 506 patients were recruited from three centers in an area with a high risk population in Colombia. The endoscopic and histopathologic studies were evaluated according to the Sydney system and the OLGA staging system proposed by Rugge. The effect of each variable on the disease (gastric cancer and dysplasia) was evaluated using bivariate and multivariate models. Statistical significance was set considering a p value inferior to 0.05. Results. Advanced stages of the OLGA system (III-IV) were associated with a higher risk of dysplasia and gastric cancer (adjusted OR = 8.71; CI95% = 5.09-14.9; p=0.001), sensitivity=54.9%, specificity=89.3% and positive likelihood ratio=5.17. Conclusions. The OLGA staging system is a risk marker for gastric cancer and dysplasia in the studied population. We recommend its implementation to improve the timely diagnosis and follow-up of patients with the highest cancer risk.

Gastric Cancer Incidence and Mortality After Endoscopic Resection of Gastric Adenoma: A Nationwide Cohort Study

INTRODUCTION

Gastric adenoma is a precursor lesion of gastric cancer. We investigated whether the removal of gastric adenoma prevented gastric cancer incidence and its mortality.

METHODS

Using the linkage of nationwide databases, we assessed gastric cancer incidence and mortality among patients who had gastric adenomas removed between 2011 and 2013 in Korea. These outcomes were compared primarily with those of the Korean general population by estimating the standardized incidence and mortality ratio and secondarily with internal control subjects who did not have gastric neoplasm after esophagogastroduodenoscopy and were matched for age, sex, and calendar year by calculating hazard ratios (HR) with the Cox proportional hazards model.

RESULTS

We identified 44,405 adenoma removal patients. During a median follow-up of 8.4 years, 1,038 (2.34%) of them were given a diagnosis of gastric cancer and a total of 524 gastric cancers were expected for a standard incidence ratio of 1.98 (95% confidence interval [CI], 1.84-2.13). A total of 199 deaths from gastric cancer were expected and 99 were observed for a standard mortality ratio of 0.50 (95% CI, 0.40-0.60). Compared with the nonadenoma cohort (n = 39,826), the adenoma removal patients had a higher risk of gastric cancer (HR, 2.84; 95% CI, 2.51-3.21) and associated mortality (HR, 1.66; 95% CI, 1.19-2.31).

DISCUSSION

Removal of gastric adenoma resulted in lower-than-expected mortality but higher-than-expected incidence due to gastric cancer than that in the general population. Our analyses indicated the importance of follow-up strategy after removal of gastric adenoma.

Gastric Intestinal Metaplasia: Real Culprit or Innocent Bystander as a Precancerous Condition for Gastric Cancer?

Gastric intestinal metaplasia (GIM), which denotes conversion of gastric mucosa into an intestinal phenotype, can occur in all regions of the stomach, including cardiac, fundic, and pyloric mucosa. Since the earliest description of GIM, its association with gastric cancer of the differentiated (intestinal) type has been a well-recognized concern. Many epidemiologic studies have confirmed GIM to be significantly associated with subsequent gastric cancer development. Helicobacter pylori, the principal etiologic factor for gastric cancer, plays the most important role in predisposing to GIM. Although the role of GIM in the stepwise progression model of gastric carcinogenesis (the so-called "Correa cascade") has come into question recently, we review the scientific evidence that strongly supports this long-standing model and propose a new progression model that builds on the Correa cascade. Eradication of H pylori is the most important method for preventing gastric cancer globally, but the effect of eradication on established GIM, is limited, if any. Endoscopic surveillance for GIM may, therefore, be necessary, especially when there is extensive corpus GIM. Recent advances in image-enhanced endoscopy with integrated artificial intelligence have facilitated the identification of GIM and neoplastic lesions, which will impact preventive strategies in the near future.

The prediction model of operative link on gastric intestinal metaplasia stage III-IV: A multicenter study

Purpose

Intestinal metaplasia plays a crucial role in the risk stratification of gastric cancer development. The objective of the study was to develop a prediction model for Operative Link on Gastric Intestinal Metaplasia (OLGIM) Stage III-IV.

Methods

We analyzed 7945 high-risk gastric cancer individuals from 115 hospitals who underwent questionnaires and gastroscope. The participants were assigned to either the development or validation cohort randomly. Demographics and clinical characteristics were obtained. The outcome measurement was OLGIM III-IV. Univariate logistic regression was used for feature selection and multivariate logistic analysis was performed to develop the nomogram. Area under the curves, calibration plots, decision curve and clinical impact analysis were used to assess the performance of the nomogram.

Results

4600 individuals and 3345 individuals were included in the development and validation cohort, of which 124 and 86 individuals were diagnosed with OLGIM III-IV, respectively. Parameters in the training validation cohort matched well and there was no significant difference between two cohorts. A nomogram model for predicting OLGIM Stage III-IV consisted of 4 significantly associated variables, including age, gender, PG I and G-17 (AUC 0.723 and 0.700 for the 2 cohorts). The nomogram demonstrated excellent performance in the calibration curve. Decision curve and clinical impact analysis suggested clinical benefit of the prediction model.

Conclusions

This reliable individualized nomogram might contribute to more accurate management for patients with OLGIM III-IV. Therefore, we suggest that this study be used as an incentive to promote the application.

Third Eye? The Assistance of Artificial Intelligence (AI) in the Endoscopy of Gastrointestinal Neoplasms

Gastrointestinal cancers are characterized by high incidence and mortality. However, there are well-established methods of screening. The endoscopy exam provides the macroscopical image and enables harvesting the tissue samples for further histopathological diagnosis. The efficiency of endoscopies relies not only on proper patient preparation, but also on the skills of the personnel conducting the exam. In recent years, a number of reports concerning the application of artificial intelligence (AI) in medicine have arisen. Numerous studies aimed to assess the utility of deep learning/ neural network systems supporting endoscopies. In this review, we summarized the most recent reports and randomized clinical trials regarding the application of AI in screening and surveillance of gastrointestinal cancers among patients suffering from esophageal, gastric, and colorectal cancer, along with the advantages, limitations, and controversies of those novel solutions.

Cluster of lifestyle risk factors for stomach cancer and screening behaviors among Korean adults

This study aimed to investigate clustering patterns of lifestyle risk factors for stomach cancer and examine the association of risk factor clusters with stomach cancer screening adherence. Data from the 2019 Korean National Cancer Screening Survey, an annual cross-sectional nationwide survey, were used. The study population included 3539 adults aged 40-74 years with no history of cancer. Six stomach cancer risk factors, including smoking, drinking, physical inactivity, obesity, meat intake, and salted food intake, as well as stomach cancer screening behaviors, were assessed. The most frequent risk factor for stomach cancer was physical inactivity, followed by smoking in males and high salted food intake in females. Compared with participants subjects with no risk factors, those with three or more risk factors were less likely to adhere to screening guidelines (males: adjusted odds ratio [aOR] = 0.35, 95% confidence interval [CI] 0.23-0.53; females: aOR = 0.32, 95% CI 0.21-0.48). Our findings indicate a disparity in stomach cancer screening, such that those with more risk factors are less likely to get screened. Increasing public awareness, providing behavioral counseling, and targeting high-risk populations for screening interventions are critical for promoting cancer screening adherence and reducing the disparity in cancer screening.

Socioeconomic inequality in organized and opportunistic screening for gastric cancer: results from the Korean National Cancer Screening Survey 2009-2022

Objectives

This study aimed to evaluate the socioeconomic inequality in gastric cancer (GC) screening in Korea. Socioeconomic inequality was assessed using both organized and opportunistic screening according to income and educational level.

Methods

GC screening data were obtained from the 2009-2022 Korean National Cancer Screening Survey. The final analysis included 47,163 cancer-free men and women. The weighted cancer screening rate was estimated using joinpoint regression. The inequality indices were measured in terms of both the absolute slope index of inequality (SII) and the relative index of inequality (RII) using the Poisson regression model.

Results

The organized screening rate for GC increased from 38.2% in 2009 to 70.8% in 2022, whereas the opportunistic screening rate decreased from 18.8 to 4.5%. Regarding educational inequality, a negative SII value was observed [-3.5, 95% confidence interval (CI), -7.63-0.83%] in organized screening, while a positive SII (9.30%; 95% CI, 6.69-11.91%) and RII (1.98%; 95% CI, 1.59-2.46) were observed in opportunistic screening. Furthermore, income inequality was not found in organized GC screening; however, overall SII and RII for opportunistic screening were 7.72% (95% CI, 5.39-10.5) and 1.61 (95% CI, 1.42-1.81), respectively.

Conclusion

Organized screening rates have grown gradually over time and account for the majority of GC screenings in South Korea. While no socioeconomic inequalities were found in organized screening, significant socioeconomic inequalities were found in opportunistic screening.

Endoscopic resection of early gastric cancer

Endoscopic resection (ER) is an effective treatment for early gastric cancer (EGC) without metastases. Existing endoscopic mucosal resection (EMR) is easy to perform, has few complications, and can be applied when the lesion size is small. However, en bloc and complete resection rates vary depending on the size and severity of the lesion. EMR using the cap-mounted panendoscopic method and EMR after circumferential preamputation of the lesion are useful in the treatment of EGC. However, completely oversized lesions (≥2 cm) and lesions associated with ulcers or submucosal fibrosis are more likely to fail resection. Endoscopic submucosal dissection has been widely used to resect tumors larger than 2 cm in diameter and has a higher acceptable complication rate and en bloc and complete resection rates than EMR. ER for EGC is superior to surgical resection in terms of improving patient quality of life. Additionally, compared to surgery, emergency rooms have a lower rate of treatment-related complications, shorter hospital stays, and lower costs. Accordingly, the indications for ER are expanding in the field of therapeutic endoscopy. Long-term outcomes regarding recurrence are excellent in both absolute and extended criteria for ER in EGC. Close surveillance should be performed after ER to detect early metachronous gastric cancer and precancerous lesions that can be treated with ER. Follow-up gastroscopy and abdominopelvic computed tomography scans every 6 to 12 months are recommended for patients who undergo curative ER for EGC on absolute or extended criteria.

Real-World Compliance of Surgical Treatment According to the Korean Gastric Cancer Guideline 2018: Evaluation From the Nationwide Survey Data 2019 in Korea

PURPOSE

This study evaluated real-world compliance with surgical treatment according to Korea's gastric cancer treatment guidelines.

MATERIALS AND METHODS

The 2018 Korean Gastric Cancer Treatment Guidelines were evaluated using the 2019 national survey data for surgically treated gastric cancer based on postoperative pathological results in Korea. In addition, the changes in surgical treatments in 2019 were compared with those in the 2014 national survey data implemented before the publication of the guidelines in 2018. The compliance rate was evaluated according to the algorithm recommended in the 2018 Korean guidelines.

RESULTS

The overall compliance rates in 2019 were 83% for gastric resection extent, 87% for lymph node dissection, 100% for surgical approach, and 83% for adjuvant chemotherapy, similar to 2014. Among patients with pathologic stages IB, II, and III disease who underwent total gastrectomy, the incidence of splenectomy was 8.08%, a practice not recommended by the guidelines. The survey findings revealed that 48.66% of the patients who underwent gastrectomy had pathological stage IV disease, which was not recommended by the 2019 guidelines. Compared to that in 2014, the rate of gastrectomy in stage IV patients was 54.53% in 2014. Compliance rates were similar across all regions of Korea, except for gastrectomy in patients with stage IV disease.

CONCLUSIONS

Real-world compliance with gastric cancer treatment guidelines was relatively high in Korea.

Impact of Coronavirus Disease 2019 on Gastric Cancer Diagnosis and Stage: A Single-Institute Study in South Korea

PURPOSE

Gastric cancer (GC) is among the most prevalent and fatal cancers worldwide. National cancer screening programs in countries with high incidences of this disease provide medical aid beneficiaries with free-of-charge screening involving upper endoscopy to detect early-stage GC. However, the coronavirus disease 2019 (COVID-19) pandemic has caused major disruptions to routine healthcare access. Thus, this study aimed to assess the impact of COVID-19 on the diagnosis, overall incidence, and stage distribution of GC.

MATERIALS AND METHODS

We identified patients in our hospital cancer registry who were diagnosed with GC between January 2018 and December 2021 and compared the cancer stage at diagnosis before and during the COVID-19 pandemic. Subgroup analyses were conducted according to age and sex. The years 2018 and 2019 were defined as the "before COVID" period, and the years 2020 and 2021 as the "during COVID" period.

RESULTS

Overall, 10,875 patients were evaluated; 6,535 and 4,340 patients were diagnosed before and during the COVID-19 period, respectively. The number of diagnoses was lower during the COVID-19 pandemic (189 patients/month vs. 264 patients/month) than before it. Notably, the proportion of patients with stages 3 or 4 GC in 2021 was higher among men and patients aged ≥40 years.

CONCLUSIONS

During the COVID-19 pandemic, the overall number of GC diagnoses decreased significantly in a single institute. Moreover, GCs were in more advanced stages at the time of diagnosis. Further studies are required to elucidate the relationship between the COVID-19 pandemic and the delay in the detection of GC worldwide.

[Metabolic syndrome and gastrointestinal cancer screening]

Cancer has become a leading cause of death among patients with metabolic syndrome (MetS). The more components of MetS a patient has, the higher his cancer risk is. MetS is causally associated with colorectal, pancreatic, gallbladder, biliary, hepatocellular, gastric and esophageal adenocarcinomas. MetS increases cancer mortality up to 2.4-fold. Intentional long-term weight loss reduces the excess cancer risk of obese MetS-patients. Preventing and treating the MetS together with GI cancer screening is effective and decreases the burden of GI cancer mortality significantly.

Validation of a pre-endoscopy risk score for predicting the presence of gastric intestinal metaplasia in a U.S. population

BACKGROUND AND AIMS

Surveillance of gastric intestinal metaplasia (GIM) may lead to early gastric cancer detection. Our purpose was to externally validate a predictive model for endoscopic GIM previously developed in a veteran population in a second U.S.

POPULATION

METHODS

We previously developed a pre-endoscopy risk model for detection of GIM using 423 GIM cases and 1796 control subjects from the Houston Veterans Affairs Hospital. The model included sex, age, race/ethnicity, smoking, and Helicobacter pylori infection with an area under the receiver-operating characteristic curve (AUROC) of .73 for GIM and .82 for extensive GIM. We validated this model in a second cohort of patients from 6 Catholic Health Initiative (CHI)-St Luke's hospitals (Houston, Tex, USA) from January to December 2017. Cases were defined as having GIM on any gastric biopsy sample and extensive GIM as involving both the antrum and corpus. We further optimized the model by pooling both cohorts and assessing discrimination using AUROC.

RESULTS

The risk model was validated in 215 GIM cases (55 with extensive GIM) and 2469 control subjects. Cases were older than control subjects (59.8 vs 54.7 years) with more nonwhites (59.1% vs 42.0%) and H pylori infections (23.7% vs 10.9%). The model applied to the CHI-St Luke's cohort had an AUROC of .62 (95% confidence interval [CI], .57-.66) for predicting GIM and of .71 (95% CI, .63-.79) for predicting extensive GIM. When the Veterans Affairs and CHI-St Luke's cohorts were pooled, discrimination of both models improved (GIM vs extensive GIM AUROC: .74 vs .82).

CONCLUSIONS

A pre-endoscopy risk prediction model was validated and updated using a second U.S. cohort with robust discrimination for endoscopic GIM. This model should be evaluated in other U.S. populations to risk-stratify patients for endoscopic GIM screening.

Association between Gastric Cancer and 12 Autoimmune Diseases: A Mendelian Randomization Study

BACKGROUND

Whether the positive associations of gastric cancer (GC) with autoimmune diseases are causal has always been controversial. This study aims to estimate the causal relationship between GC and 12 autoimmune diseases by means of Mendelian randomization (MR) analysis.

METHODS

After rigorous evaluation, potential candidate single nucleotide polymorphisms (SNPs) for GC and 12 autoimmune diseases were extracted from genome-wide association study (GWAS) datasets. We performed the MR analyses using the inverse variance weighted (IVW) method as the primary approach to the analysis. Three sensitivity analysis methods were added to assess the robustness of the results. In addition, heterogeneity was measured using Cochran's Q-value, and horizontal pleiotropy was assessed using MR-Egger regression and leave-one-out analysis.

RESULTS

The IVW result, which is the main method of analysis, shows no evidence of a causal association between GC and any autoimmune disease. The results of IVW analysis show the relationship between rheumatoid arthritis (p = 0.1389), systemic lupus erythematosus (p = 0.1122), Crohn's disease (p = 0.1509), multiple sclerosis (p = 0.3944), primary sclerosing cholangitis (p = 0.9022), primary biliary cirrhosis (p = 0.7776), type 1 diabetes (p = 0.9595), ulcerative colitis (p = 0.5470), eczema (p = 0.3378), asthma (p = 0.7436), celiac disease (p = 0.4032), and psoriasis (p = 0.7622) and GC susceptibility. The same result was obtained with the weighted median and the MR-egger (p > 0.05).

CONCLUSION

Our study did not find a genetic causal relationship between susceptibility to these autoimmune diseases and GC, which suggests that unmeasured confounders (e.g., inflammatory processes) or shared genetic architecture may be responsible for the reported epidemiologic associations. Further studies of ancestral diversity are warranted to validate such causal associations.

Single-cell transcriptomic analysis reveals crucial oncogenic signatures and its associative cell types involved in gastric cancer

The intricate association of oncogenic markers negatively impacts accurate gastric cancer diagnosis and leads to the proliferation of mortality rate. Molecular heterogeneity is inevitable in determining gastric cancer's progression state with multiple cell types involved. Identification of pathogenic gene signatures is imperative to understand the disease's etiology. This study demonstrates a systematic approach to identifying oncogenic gastric cancer genes linked with different cell types. The raw counts of adjacent normal and gastric cancer samples are subjected to a quality control step. The dimensionality reduction and multidimensional clustering are performed using Principal Component Analysis (PCA) and Uniform Manifold Approximation and Projection (UMAP) techniques. The adjacent normal and gastric cancer sample cell clusters are annotated with the Human Primary Cell Atlas database using the "SingleR." Cellular state transition between the distinct groups is characterized using trajectory analysis. The ligand-receptor interaction between Vascular Endothelial Growth Factor (VEGF) and cell clusters unveils crucial molecular pathways in gastric cancer progression. Chondrocytes, Smooth muscle cells, and fibroblast cell clusters contain genes contributing to poor survival rates based on hazard ratio during survival analysis. The GC-related oncogenic signatures are isolated by comparing the gene set with the DisGeNET database. Twelve gastric cancer biomarkers (SPARC, KLF5, HLA-DRB1, IGFBP3, TIMP3, LGALS1, IGFBP6, COL18A1, F3, COL4A1, PDGFRB, COL5A2) are linked with gastric cancer and further validated through gene set enrichment analysis. Drug-gene interaction found PDGFRB, interacting with various anti-cancer drugs, as a potential inhibitor for gastric cancer. Further investigations on these molecular signatures will assist the development of precision therapeutics, promising longevity among gastric cancer patients.

Chronic Periodontitis and the Potential Likelihood of Gastric Cancer: A Nested Case-Control Study in the Korean Population Utilizing a National Health Sample Cohort

There is limited information regarding the potential association between chronic periodontitis (CP) and gastric cancer, especially in the Korean population. This study aimed to explore this relationship. This nested case-control study analyzed data from 10,174 patients with gastric cancer and 40,696 controls from the Korean National Health Insurance Service-National Sample Cohort using propensity score matching. Standardized differences were used to compare baseline characteristics between study groups. Logistic regression analyses adjusted for confounders were conducted to assess the association between history of CP and gastric cancer occurrence. CP histories and comprehensive subgroup analyses in the 1- and 2-year periods preceding the index date were evaluated. Individuals with a history of CP within the 1-year and 2-year periods showed an increased likelihood of developing gastric cancer. Subgroup analyses consistently supported these findings in male participants aged <65 years and individuals with various income levels or living in residential areas. However, no significant associations were observed among participants aged ≥65 years. In conclusion, CP may be a potential risk factor for gastric cancer development in the Korean population. Regular screening for gastric cancer may be necessary for high-risk individuals, specifically men aged <65 years with a history of CP.