Adenocarcinomas at different positions at the gastro-oesophageal junction show distinct association with gastritis and gastric preneoplastic conditions

Myths and misconceptions in the management of Helicobacter pylori infection

The discovery of Helicobacter pylori infection in 1984 revolutionised the management of several common upper gastrointestinal diseases. However, some of the clinical practices that were adopted following discovery of this organism have become less appropriate over the intervening years. This article discusses five 'myths and misconceptions' that we believe have now emerged and which we argue need re-evaluation. Although the prevalence of H. pylori infection is decreasing in some developed countries, it remains a huge global problem and the most serious consequence of infection, gastric adenocarcinoma, is still a major cause of mortality. The epidemiology of H. pylori-related diseases is also changing and careful testing remains crucially important, especially in patients with peptic ulceration. Eradication of H. pylori infection has also become much more difficult over recent years as a result of the widespread acquisition of antibiotic resistance. Routine assessment of the success of eradication should therefore now be performed. Finally, there has been increased awareness about the role of H. pylori in the multistep pathway of gastric carcinogenesis, about the opportunities to prevent cancer development by eradicating this infection in some individuals and about detecting high-risk preneoplastic changes via endoscopic surveillance. The discovery of H. pylori was rightly honoured by the award of the Nobel prize for Physiology and Medicine in 2005. However, unless we re-evaluate and update the ways in which we manage H. pylori infection, much of the fantastic progress that has been made in this field of medicine may tragically be lost once again.

Esophagogastric junction adenocarcinoma shares characteristics with gastric adenocarcinoma: Literature review and retrospective multicenter cohort study

The incidence of esophagogastric junction (EGJ) adenocarcinoma has been gradually increasing in Asia, just like in Western countries a few decades ago. Despite recent advances in next-generation sequencing and multimodal treatments, EGJ adenocarcinoma is still an aggressive malignancy with poor outcomes. Clinically, EGJ adenocarcinoma can be separated into Barrett's adenocarcinoma and cardiac adenocarcinoma, with frequent similarities observed. Barrett's adenocarcinoma is likely to be of gastric origin in terms of its premalignant background, risk factors, and stem cell regulators. Recent comprehensive genomic analyses suggest that immunotherapy may be essential for high-level microsatellite instability (MSI-H)- and Epstein-Barr virus (EBV)-associated subtypes, and against the immunosuppressive phenotype in genomically stable (GS) subtypes, in the treatment of EGJ and gastric adenocarcinoma. Although the chromosomal instability (CIN) subtype dominates EGJ adenocarcinoma, there is still a need to investigate the other molecular subtypes and their targets. Because of the distinctive characteristics of tumor location of EGJ adenocarcinoma, we also described the results of a multicenter cohort study of EGJ adenocarcinoma, comparing Siewert type I (distal esophagus), II (cardia of the stomach), and III (subcardia) tumors. We show that type I tumors were frequently accompanied by Barrett's esophagus (78%, P < .0001), with a significantly unfavorable outcome (multivariate EGJ-cancer-specific mortality hazard ratio = 1.81, 95% CI, 1.06-2.97; P = .031). In addition, over half (56%) of these cases experienced disease recurrence in the lymph nodes. Our findings suggest that Barrett's adenocarcinoma may be an aggressive phenotype of EGJ adenocarcinoma due to the potential risk of tumor spread through the complex lympho-vascular network of the esophagus.

The role of the gastric bacterial microbiome in gastric cancer: Helicobacter pylori and beyond

A link between chronic inflammation and carcinogenesis has been depicted in many organ systems. Helicobacter pylori is the most prevalent bacterial pathogen, induces chronic gastritis and is associated with more than 90% of cases of gastric cancer (GC). However, the introduction of nucleotide sequencing techniques and the development of biocomputional tools have surpassed traditional culturing techniques and opened a wide field for studying the mucosal and luminal composition of the bacterial gastric microbiota beyond H. pylori. In studies applying animal models, a potential role in gastric carcinogenesis for additional bacteria besides H. pylori has been demonstrated. At different steps of gastric carcinogenesis, changes in bacterial communities occur. Whether these microbial changes are a driver of malignant disease or a consequence of the histologic progression along the precancerous cascade, is not clear at present. It is hypothesized that atrophy, as a consequence of chronic gastric inflammation, alters the gastric niche for commensals that might further urge the development of H. pylori-induced GC. Here, we review the current state of knowledge on gastric bacteria other than H. pylori and on their synergism with H. pylori in gastric carcinogenesis.

Transcriptomic profiling reveals three molecular phenotypes of adenocarcinoma at the gastroesophageal junction

Cancers occurring at the gastroesophageal junction (GEJ) are classified as predominantly esophageal or gastric, which is often difficult to decipher. We hypothesized that the transcriptomic profile might reveal molecular subgroups which could help to define the tumor origin and behavior beyond anatomical location. The gene expression profiles of 107 treatment-naïve, intestinal type, gastroesophageal adenocarcinomas were assessed by the Illumina-HTv4.0 beadchip. Differential gene expression (limma), unsupervised subgroup assignment (mclust) and pathway analysis (gage) were undertaken in R statistical computing and results were related to demographic and clinical parameters. Unsupervised assignment of the gene expression profiles revealed three distinct molecular subgroups, which were not associated with anatomical location, tumor stage or grade (p > 0.05). Group 1 was enriched for pathways involved in cell turnover, Group 2 was enriched for metabolic processes and Group 3 for immune-response pathways. Patients in group 1 showed the worst overall survival (p = 0.019). Key genes for the three subtypes were confirmed by immunohistochemistry. The newly defined intrinsic subtypes were analyzed in four independent datasets of gastric and esophageal adenocarcinomas with transcriptomic data available (RNAseq data: OCCAMS cohort, n = 158; gene expression arrays: Belfast, n = 63; Singapore, n = 191; Asian Cancer Research Group, n = 300). The subgroups were represented in the independent cohorts and pooled analysis confirmed the prognostic effect of the new subtypes. In conclusion, adenocarcinomas at the GEJ comprise three distinct molecular phenotypes which do not reflect anatomical location but rather inform our understanding of the key pathways expressed.

Histopathology Findings in Patients Undergoing Laparoscopic Sleeve Gastrectomy

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) has gained popularity in the last 10 years for its good results in weight loss and comorbidity control. However, guidelines on the pathological examination of the specimen are lacking. The aim of this retrospective study was to determine the usefulness of the routine specimen examination when presurgery endoscopy (upper gastrointestinal endoscopy, UGIE) and multiple gastric biopsies are part of the preoperative work-up.

METHODS

A retrospective review of records of the patients submitted to LSG between January 2012 and August 2017 was carried out. Sex, age, histopathology findings in the presurgery endoscopy biopsies and surgical specimen, and the prevalence of Helicobacter pylori infection were analyzed.

RESULTS

A total of 925 patients entered the study group (mean age = 44.1 years, Females = 80.3%, BMI = 44.58 kg/m²). The most common histopathology pattern in the endoscopy biopsies and in the surgical specimens was inactive chronic gastritis (64.4 and 55.6%, respectively). Helicobacter pylori infection was 24.6 and 2.48%, respectively. Ninety-nine percent (n 796) of patients with non-significant endoscopy biopsy findings showed the same patterns in specimen analysis. Only three patients (0.3%) who had intestinal presurgery metaplasia were positive in the specimen analysis, and two cases of gastric stromal neoplasms (gastrointestinal stromal tumor and gastric leiomyoma) were found intraoperatively.

CONCLUSION

Most of the findings are non-significant and can be predicted if UGIE plus multiple biopsies is routinely included in the bariatric work-up with significant cost reduction. In those patients who had a significant finding prior to the surgery or intraoperatively, the pathological examination of the specimen is recommended.

Development and validation of a prediction rule for estimating gastric cancer risk in the Chinese high-risk population: a nationwide multicentre study

OBJECTIVE

To develop a gastric cancer (GC) risk prediction rule as an initial prescreening tool to identify individuals with a high risk prior to gastroscopy.

DESIGN

This was a nationwide multicentre cross-sectional study. Individuals aged 40-80 years who went to hospitals for a GC screening gastroscopy were recruited. Serum pepsinogen (PG) I, PG II, gastrin-17 (G-17) and anti-Helicobacter pylori IgG antibody concentrations were tested prior to endoscopy. Eligible participants (n=14 929) were randomly assigned into the derivation and validation cohorts, with a ratio of 2:1. Risk factors for GC were identified by univariate and multivariate analyses and an optimal prediction rule was then settled.

RESULTS

The novel GC risk prediction rule comprised seven variables (age, sex, PG I/II ratio, G-17 level, H. pylori infection, pickled food and fried food), with scores ranging from 0 to 25. The observed prevalence rates of GC in the derivation cohort at low-risk (≤11), medium-risk (12-16) or high-risk (17-25) group were 1.2%, 4.4% and 12.3%, respectively (p<0.001).When gastroscopy was used for individuals with medium risk and high risk, 70.8% of total GC cases and 70.3% of early GC cases were detected. While endoscopy requirements could be reduced by 66.7% according to the low-risk proportion. The prediction rule owns a good discrimination, with an area under curve of 0.76, or calibration (p<0.001).

CONCLUSIONS

The developed and validated prediction rule showed good performance on identifying individuals at a higher risk in a Chinese high-risk population. Future studies are needed to validate its efficacy in a larger population.

OLGA Gastritis Staging for the Prediction of Gastric Cancer Risk: A Long-term Follow-up Study of 7436 Patients

OBJECTIVES

Gastritis OLGA-staging ranks the risk for gastric cancer (GC) in progressive stages (0-IV). This long-term follow-up study quantifies the GC risk associated with each OLGA stage.

METHODS

Consecutive patients (7436) underwent esophagogastroscopy (T-0), with mapped gastric biopsies, OLGA staging, and H. pylori status assessment. Patients with neoplastic lesion (invasive or non-invasive) at the index endoscopy (and/or within 12 months) were excluded. All patients were followed-up (T-1) by combining different sources of clinical/pathological information (Regional Registries of: (i) esophagogastroduodenoscopies; (ii) pathology reports; (iii) cancer, (iv) mortality). The endpoint was histologically documented development of gastric epithelial neoplasia.

RESULTS

At T-0, the patients' distribution by OLGA stage was: Stage 0 = 80.8%; Stage I = 12.6%; Stage II = 4.3%; Stage III = 2.0%; Stage IV = 0.3%; H. pylori infection was detected in 25.9% of patients. At the end of the follow-up (mean/median = 6.3/6.6 years), 28 incident neoplasia were documented (overall prevalence = 0.60 per 10³/person-years; low-grade intraepithelial neoplasia = 17/28; high-grade intraepithelial neoplasia = 4/28; GC = 7/28). By OLGA stage at the enrollment, the rate of incident neoplasia was: Stage 0 = 1 case; rate/10³ person-years = 0.03; 95%CI: 0.004-0.19; Stage I = 2 cases; rate/10³ person-years = 0.34; 95%CI: 0.09-1.36; Stage II = 3 cases; rate/10³ person-years = 1.48; 95%CI: 0.48-4.58; Stage III = 17 cases; rate/10³ person-years = 19.1; 95%CI: 11.9-30.7; Stage IV = 5 cases; rate/10³ person-years = 41.2; 95%CI: 17.2-99.3. Multivariate analysis including gender, age, H. pylori status, and OLGA stage at enrollment only disclosed OLGA stage as predictor of neoplastic progression (OLGA stage III: HR = 712.4, 95%CI = 92.543-5484.5; OLGA stage IV: HR = 1450.7, 95%CI = 166.7-12626.0).

CONCLUSIONS

Among 7436 patients, OLGA stages at the enrollment correlated significantly with different risk for gastric neoplasia. Based on the obtained results, gastritis staging is a critical adjunct in endoscopy follow-up protocols aimed at GC secondary prevention.

Perioperative Therapy of Oesophagogastric Adenocarcinoma: Mainstay and Future Directions

Perioperative chemotherapy improves overall survival in patients with oesophagogastric adenocarcinoma (OAC) and locoregional disease. The mainstay of perioperative chemotherapy in these patients is a platinum/fluoropyrimidine combination. The phase III FLOT4 trial has shown that the FLOT triplet regimen (oxaliplatin, infusional 5-FU, and docetaxel) improves the outcome of patients with OAC and locoregional disease as compared to the ECF triplet (epirubicin, cisplatin, and infusional 5-FU). Targeted therapies have currently no role in the perioperative setting for the treatment of patients with OAC. For patients with oligometastatic disease, upfront gastrectomy followed by chemotherapy did not show any survival benefit compared with chemotherapy alone and thus should be discouraged. Whether surgery should be offered to patients with metastatic OAC achieving a systemic control after upfront chemotherapy is under scrutiny in the phase III FLOT5/Renaissance trial. After neoadjuvant treatment, lymph node status but not pathologic tumor response is an independent factor in the prediction of overall survival. Growing evidence suggests that perioperative chemotherapy may be associated with an increased mortality risk in patients with microsatellite instable (MSI)/mismatch repair-deficient (MMRD) adenocarcinoma, thus validating poor responsiveness to chemotherapy in MSI patients with locoregional disease.

Role of frailty and nutritional status in predicting complications following total gastrectomy with D2 lymphadenectomy in patients with gastric cancer: a prospective study

PURPOSE

This study was performed to determine the association of frailty and nutritional status with postoperative complications after total gastrectomy (TG) with D2 lymphadenectomy in patients with gastric cancer.

METHODS

Patients undergoing TG with D2 lymphadenectomy for gastric cancer between August 2014 and February 2016 were enrolled. Frailty was evaluated by sarcopenia which was diagnosed by a combination of third lumbar vertebra muscle index (L3 MI), handgrip strength, and 6-m usual gait speed. Nutritional status was evaluated by the nutritional risk screening 2002 (NRS 2002) score. Univariate and multivariate analyses evaluating the risk factors for postoperative complications were performed.

RESULTS

A total of 158 patients were analyzed, and 27.2 % developed complications within 30 days of surgery. One patient died within 30 days of the operation. In the univariate analyses, NRS 2002 score ≥3 (OR = 2.468, P = 0.012), sarcopenia (OR = 2.764, P = 0.008), and tumor located at the cardia (OR = 2.072, P = 0.046) were associated with the postoperative complications. Multivariable analysis revealed that sarcopenia (OR = 3.084, P = 0.005) and tumor located at the cardia (OR = 2.347, P = 0.026) were independent predictors of postoperative complications.

CONCLUSIONS

This study showed a significant relationship between postoperative complications and geriatric frailty using sarcopenia in patients with gastric cancer after TG with D2 lymphadenectomy. Frailty should be integrated into preoperative risk assessment and may have implications in preoperative decisionmaking.