Upper gastrointestinal cancer and reflux disease

Helicobacter pylori Status May Differentiate Two Distinct Pathways of Gastric Adenocarcinoma Carcinogenesis

BACKGROUND

We evaluated the phenotype of sporadic gastric cancer based on HP status and binding of a tumor risk marker monoclonal, Adnab-9.

METHODS

We compared a familial GC kindred with an extremely aggressive phenotype to HP-positive (HP+) and -negative (HP-) sporadic gastric adenocarcinoma (GC) patients in the same community to determine if similar phenotypes exist. This might facilitate gene discovery to understand the pathogenesis of aggressive GC phenotypes, particularly with publications implicating immune-related gene-based signatures, and the development of techniques to gauge the stance of the innate immune system (InImS), such as the FERAD ratio (blood ferritin:fecal Adnab-9 binding OD-background binding). Resection specimens for the sporadic and familial group were stained for HP and examined for intestinal metaplasia (IM) and immunostaining for Adnab-9. Familial kindred specimens were also tested for the E-cadherin mutation and APC (adenomatous polyposis coli). Survival was evaluated.

RESULTS

Of 40 GC patients, 25% were HP+ with a greater proportion of intestinal metaplasia (IM) and gastric atrophy than the HP- group. The proband of the familial GC kindred, a 32-year-old mother with fatal GC, was survived by 13-year-old identical twins. Twin #1 was HP- with IM and Twin #2 was HP+. Both twins subsequently died of GC within two years. The twins did not have APC or E-cadherin mutations. The mean overall survival in the HP+ sporadic GC group was 2.47 ± 2.58 years and was 0.57 ± 0.60 years in the HP- group (p = 0.01). Survival in the kindred was 0.22 ± 0.24 years. Adnab-9 labeling was positive in fixed tissues of 50% of non-familial GC patients and in gastric tissue extract from Twin #2. The FERAD ratio was determined separately in six prospectively followed patient groups (n = 458) and was significantly lower in the gastric cancer patients (n = 10) and patients with stomach conditions predisposing them to GC (n = 214), compared to controls (n = 234 patients at increased risk for colorectal cancer but without cancer), suggesting a failure of the InImS.

CONCLUSION

The HP+ sporadic GC group appears to proceed through a sequence of HP infection, IM and atrophy before cancer supervenes, and the HP- phenotype appear to omit this sequence. The familial cases may represent a subset with both features, but the natural history strongly resembles that of the HP- group. Two different paths of carcinogenesis may exist locally for sporadic GC. The InImS may also be implicated in prognosis. Identifying these patients will allow for treatment stratification and early diagnosis to improve GC survival.

Identifying Disease of Interest With Deep Learning Using Diagnosis Code

BACKGROUND

Autoencoder (AE) is one of the deep learning techniques that uses an artificial neural network to reconstruct its input data in the output layer. We constructed a novel supervised AE model and tested its performance in the prediction of a co-existence of the disease of interest only using diagnostic codes.

METHODS

Diagnostic codes of one million randomly sampled patients listed in the Korean National Health Information Database in 2019 were used to train, validate, and test the prediction model. The first used AE solely for a feature engineering tool for an input of a classifier. Supervised Multi-Layer Perceptron (sMLP) was added to train a classifier to predict a binary level with latent representation as an input (AE + sMLP). The second model simultaneously updated the parameters in the AE and the connected MLP classifier during the learning process (End-to-End Supervised AE [EEsAE]). We tested the performances of these two models against baseline models, eXtreme Gradient Boosting (XGB) and naïve Bayes, in the prediction of co-existing gastric cancer diagnosis.

RESULTS

The proposed EEsAE model yielded the highest F1-score and highest area under the curve (0.86). The EEsAE and AE + sMLP gave the highest recalls. XGB yielded the highest precision. Ablation study revealed that iron deficiency anemia, gastroesophageal reflux disease, essential hypertension, gastric ulcers, benign prostate hyperplasia, and shoulder lesion were the top 6 most influential diagnoses on performance.

CONCLUSION

A novel EEsAE model showed promising performance in the prediction of a disease of interest.

Correlation analysis and prognostic value of miR-29a-3p expression and CYP2C19 genotypes in exfoliated cells from tongue coating of patients with gastroesophageal reflux disease

BACKGROUND

Gastroesophageal reflux disease (GERD) is a highly prevalent and troublesome disease. Several differentially expressed microRNAs (miRNAs) have been found in GERD.

OBJECTIVE

This study was to analyze the correlation of miR-29a-3p expression and CYP2C19 genotypes in exfoliated cells from tongue coating of GERD patients and its prognostic value.

METHODS

Tongue coating specimens were collected from 130 GERD patients and 70 healthy volunteers and their clinical baseline information was recorded. miR-29a-3p expression in exfoliated cells from tongue coating was determined via RT-qPCR, and its diagnostic efficiency on GERD was evaluated via receiver operating characteristic curve. CYP2C19 genotypes and their correlation with miR-29a-3p were analyzed via polymerase chain reaction restriction fragment length polymorphism technique. The adverse events of patients were documented via 12-month follow-up. The impact of miR-29a-3p expression on the healing rate of patients was analyzed via Kaplan-Meier method. Qualification of miR-29a-3p as an independent prognostic factor of GERD patients was analyzed via multivariate Cox regression analysis.

RESULTS

miR-29a-3p was highly-expressed in exfoliated cells from tongue coating of GERD patients. miR-29a-3p expression had high specificity and sensitivity in diagnosing GERD. CYP2C19 genotypes in GERD patients comprised rapid metabolizers, intermedia metabolizers, and poor metabolizers. miR-29a-3p expression showed a correlation with CYP2C19 genotypes. Higher miR-29a-3p expression predicted higher cumulative incidences of adverse outcomes. Highly-expressed miR-29a-3p was an independent prognostic factor for adverse outcomes of GERD patients.

CONCLUSION

High expression of miR-29a-3p aided the diagnosis and predicted poor prognosis of GERD patients.

Evaluation of CSTB and DMBT1 expression in saliva of gastric cancer patients and controls

Background

Gastric cancer (GC) is the fifth most common cancer and the third cause of cancer deaths globally, with late diagnosis, low survival rate, and poor prognosis. This case-control study aimed to evaluate the expression of cystatin B (CSTB) and deleted in malignant brain tumor 1 (DMBT1) in the saliva of GC patients with healthy individuals to construct diagnostic algorithms using statistical analysis and machine learning methods.

Methods

Demographic data, clinical characteristics, and food intake habits of the case and control group were gathered through a standard checklist. Unstimulated whole saliva samples were taken from 31 healthy individuals and 31 GC patients. Through ELISA test and statistical analysis, the expression of salivary CSTB and DMBT1 proteins was evaluated. To construct diagnostic algorithms, we used the machine learning method.

Results

The mean salivary expression of CSTB in GC patients was significantly lower (115.55 ± 7.06, p = 0.001), and the mean salivary expression of DMBT1 in GC patients was significantly higher (171.88 ± 39.67, p = 0.002) than the control.

Multiple linear regression analysis demonstrated that GC was significantly correlated with high levels of DMBT1 after controlling the effects of age of participants (R² = 0.20, p < 0.001).

Considering salivary CSTB greater than 119.06 ng/mL as an optimal cut-off value, the sensitivity and specificity of CSTB in the diagnosis of GC were 83.87 and 70.97%, respectively. The area under the ROC curve was calculated as 0.728. The optimal cut-off value of DMBT1 for differentiating GC patients from controls was greater than 146.33 ng/mL (sensitivity = 80.65% and specificity = 64.52%). The area under the ROC curve was up to 0.741.

As a result of the machine learning method, the area under the receiver-operating characteristic curve for the diagnostic ability of CSTB, DMBT1, demographic data, clinical characteristics, and food intake habits was 0.95. The machine learning model’s sensitivity, specificity, and accuracy were 100, 70.8, and 80.5%, respectively.

Conclusion

Salivary levels of DMBT1 and CSTB may be accurate in diagnosing GCs. Machine learning analyses using salivary biomarkers, demographic, clinical, and nutrition habits data simultaneously could provide affordability models with acceptable accuracy for differentiation of GC by a cost-effective and non-invasive method.

The uninvited guests of our microbiome: Helicobacter pylori and Epstein-Barr virus and their role in gastric cancerogenesis

It is well established that human body is an ecosystem for numerous microorganisms: bacteria, fungi, eukaryotic parasites, and viruses. They form a “microbiome” that under conditions of homeostasis remains in a friendly mutual relationship with the host. However, the composition and diversity of this microbe community is dynamic and can be changed under the influence of environmental factors, such as diet, antibiotic therapy, lifestyle, and the host’s genotype and immunity. The result of gut microbiome dysbiosis can lead even to cancer. The aim of this review is the description of the healthy gastrointestinal microbiome and the role of two infectious agents: Gram-negative bacteria Helicobacter pylori and Epstein-Barr virus in the development of gastric cancer in terms of gut dysbiosis. H. pylori is the most important pathogen of gastric microbiome with clear impact on its diversity. Coinfection with Epstein-Barr virus causes chronic gastritis, and the inflammatory process is significantly increased. The process of carcinogenesis begins with chronic inflammation that causes atrophic gastritis, intestinal metaplasia, dysplasia, and finally cancer. It has been proven that chronic inflammatory infection caused by infectious agents increases the risk of stomach cancer. Molecular methods that are progressively used to explore the human microbiome provide hope that this knowledge will be used for future diagnoses and therapy in the state of its dysbiosis and in cases of gastric cancer.

A comprehensive update on early gastric cancer: defining terms, etiology, and alarming risk factors

INTRODUCTION

Early gastric cancer (EGC) is a well-defined gastric malignancy that is limited to the mucosa or submucosa, irrespective of lymph node metastasis. At an early stage, gastric cancer often does not cause symptoms until it becomes advanced, and it is a heterogeneous disease and usually encountered in its late stages.

AREA COVERED

This comprehensive review will provide a novel insight into the evaluation of EGC epidemiology, defining terms, extensive etiology and risk factors, and timely diagnosis since prevention is an essential approach for controlling this cancer and reducing its morbidity and mortality.

EXPERT OPINION

The causative manner of EGC is complex and multifactorial. In recent years, researchers have made significant contributions to understanding the etiology and pathogenesis of EGC, and standardization in the evaluation of disease activity. Though the incidence of this cancer is steadily declining in some advanced societies owing to appropriate interventions, there remains a serious threat to health in developing nations. Early detection of resectable gastric cancer is crucial for better patient outcomes.

A Rare Disease of the Digestive Tract: Esophageal Melanosis

Esophageal melanosis which is characterized by melanocytic proliferation in the squamous epithelium of the esophagus and melanin accumulatin of esophageal mucosa (EM) is a rare disease of the digestive system. Although esophageal melanosis is considered to be a benign disease, its etiology is not cleared and has been reported to be the precursor lesion of esophageal primary melanomas. In this report, we aimed to note esophageal melanosis in a 55-year-old female case who applied to our clinic with difficulty in swallowing, burning behind the breastbone in the stomach, heartburn, indigestion, and pain in the upper abdomen after endoscopic and pathologic evaluation. Complaints dropped with anti-acid therapy and case was followed by intermittent endoscopic procedures because of precursor melanocytic lesions.

Family history and survival of patients with gastric cancer: a meta-analysis

BACKGROUND

Previous studies have generated conflicting evidence regarding associations between family history and survival after gastric cancer surgery. In this study, we investigated this question using a meta-analysis.

MATERIALS AND METHODS

To identify relevant studies, PubMed and Embase databases were searched up to June 2013. Two reviewers independently assessed search results and data extraction of included studies. Hazard ratios (HRs) and 95% confidence intervals (CIs) for overall survival (OS) were calculated based on fixed- or random- effects models. Homogeneity of effects across studies was assessed using x2 test statistics and quantified by I2.

RESULTS

A total of five studies were selected according to the inclusion criteria. The total number of patients included was 2,030, which ranged from 145 to 598 per study. There was no significant difference in OS by family history of cancer (HR=0.83, 95%CIs=0.50-1.38), but subgroup analysis of patients with a first-degree family history of cancer (HR=0.74, 95%CIs=0.60-0.93) and gastric cancer family history (HR=0.56, 95%CIs=0.41-0.76) tended to show better OS in these patients.

CONCLUSIONS

This meta-analysis suggests that a first-degree family history of cancer or gastric cancer family history is associated with better survival of gastric cancer patients after surgery, after a systematic review of five previous studies. These results can be applied by clinicians when counselling patients regarding their risk of death from gastric cancer. Further study is needed to investigate the underlying mechanism between family history and survival in gastric cancer patients.

Higher incidence of gastroesophageal reflux disease after gastric wedge resections of gastric submucosal tumors located close to the gastroesophageal junction

Purpose

We hypothesized that gastroesophageal reflux disease (GERD) would be more prevalent after a gastric wedge resection of a submucosal tumor (SMT) located close to the gastroesophageal junction (GEJ) than after a gastric wedge resection of an SMT at other locations because of the damage to the lower esophageal sphincter during surgery.

Methods

Fifty-eight patients with gastric SMT who underwent open or laparoscopic gastric wedge resection between January 2000 and August 2012 at the Department of Surgery, Incheon St. Mary's Hospital were enrolled into this study. The patients were divided into 2 groups according to the location of the tumor, upper or lateral border of the tumor within 5 cm of the GEJ (GEJ ≤ 5 cm group) and upper or lateral border of the tumor greater than 5 cm distal to the GEJ (GEJ > 5 cm group). The surgical records, clinicopathologic findings, postoperative GERD symptoms, postoperative use of acid suppressive medications and preoperative and postoperative endoscopic findings were retrospectively reviewed and compared between the 2 groups.

Results

There was no difference in the frequency of the preoperative GERD symptoms between the 2 groups, whereas postoperative GERD symptoms and postoperative use of acid suppressive medications were more frequent in the GEJ ≤ 5 cm group (P = 0.045 and P = 0.031). However, there were no differences in the follow-up endoscopic findings in terms of reflux esophagitis and Hill's grade between the 2 groups.

Conclusion

The incidence of GERD was higher after gastric wedge resection of SMTs located close to the GEJ. Hence, adequate care should be taken during the follow-up of these patients.

The association between physical activity and gastroesophageal cancer: systematic review and meta-analysis

Physical activity may decrease gastroesophageal cancer risk through a reduction of oxidative stress and decreased chronic inflammation, yet few epidemiologic studies have been able to report a clear inverse association between physical activity and gastroesophageal cancer. Because no meta-analysis has investigated the relation of physical activity to gastroesophageal cancer, we conducted a comprehensive systematic review and meta-analysis according to the PRISMA guidelines based on 24 studies with a total of 15,745 cases. When we compared high versus low physical activity levels and summarized associations according to anatomic site and tumor histology, risk reductions were evident for esophageal adenocarcinoma [relative risk (RR) = 0.79, 95% confidence interval (CI) = 0.66-0.94], gastric cardia adenocarcinoma (RR = 0.83, 95% CI = 0.69-0.99) and gastric non-cardia adenocarcinoma (RR = 0.72, 95% CI = 0.62-0.84). The risk reduction for esophageal squamous cell carcinoma (RR = 0.94, 95% CI = 0.41-2.16) became statistically significant (RR = 0.66, 95% CI = 0.46-0.96) after excluding an influential study. The test for heterogeneity by gastroesophageal cancer subtype was statistically non-significant (p-difference = 0.71). The RR of total gastroesophageal cancer for high versus low physical activity was 0.82 (95% CI = 0.74-0.90). A dose-response analysis of frequency of physical activity and total gastroesophageal cancer risk revealed that the greatest risk reduction was achieved among those engaging in moderate to vigorous physical activity five times per week (RR = 0.67, 95% CI = 0.58-0.79). Our results provide support for an inverse relation of physical activity, in particular exercise frequency, to gastroesophageal cancer risk.