Gastric epithelial dysplasia: characteristics and long-term follow-up results after endoscopic resection according to morphological categorization

Prevalence and endoscopic-histological correlation of premalignant gastric lesions at a university hospital in Uruguay

Background and study aims

Although chronic atrophic gastritis (CAG), intestinal metaplasia (IM), and dysplasia constitute gastric pre-neoplastic conditions of gastric cancer (GC), data on endoscopic correlation and the prevalence in many South American countries are scarce. The aims of this study were to establish prevalence and perform endoscopic-histological correlation of gastric pre-neoplastic conditions using high-definition white light endoscopy (WLE) and to determine interobserver agreement for endoscopic findings for CAG and IM.

Patients and methods

A prospective, observational, descriptive, cross-sectional study was carried out at a Uruguayan hospital during a 6-month period. Risk was stratified according to Operative Link for Gastritis Assessment and Operative Link for Gastric Intestinal Metaplasia stage for CAG and IM, respectively. An independent and blinded second observer was included to determine interobserver endoscopic and histologic agreement.

Results

A total of 102 patients (mean age 57 years ± 1.6 years, 68.6% woman) were included. Prevalence of histological CAG and IM were 38.2% and IM 31.4%, respectively. Endoscopic-histological correlation for CAG had kappa index 0.063, sensitivity 46%, and specificity 60%. For endoscopic IM, the kappa index was 0.216, sensitivity 22%, and specificity 96%. Interobserver variability was good for gastric fold flattening and very good in the presence of whitish-greyish plaques for CAG and IM, respectively.

Conclusions

The endoscopic-histological correlation of both CAG and IM was low, raising the need for biopsy for diagnosis in all cases, regardless of HD-WLE findings. Although prevalence of gastric pre-neoplastic conditions in this group of Uruguayan patients was comparable to those described in countries with a high incidence of GC, a low proportion of high-risk stages (III and IV) was identified.

The molecular profile of gastric intraepithelial foveolar type neoplasia based on somatic copy number alterations and multiple mutation analysis

BACKGROUND

Gastric foveolar type neoplasia is a rare histological variant of gastric tumors. It is very difficult to differentiate between benign and malignant intraepithelial foveolar neoplasia (IFN). Although limited molecular alterations have been identified in IFNs, somatic copy number alterations (SCNAs), which are linked to tumor progression, have not been systematically evaluated in IFN.

METHODS

The aim of the present study was to comprehensively examine SCNAs using a SNP array in 37 cases of IFN, compared with intestinal type dysplasia, including 39 low grade (LGD) and 32 high grade dysplasia (HGD) cases. In addition, gene mutations were evaluated using a gene panel. Finally, we attempted to determine molecular profiles using a hierarchical clustering analysis.

RESULTS

Two patterns could be categorized according to the SCNAs in 108 tumors examined: high (subgroup 1) and low (subgroup 2) frequencies of SCNAs. Although IFN and LGD were associated with subgroup 2, HGD was found in both subgroups. The median numbers of total SCNAs and copy number gains were higher in IFN or HGD than in LGD. In addition, the IFN genotype was characterized by altered genes located at 4p13-4q35.2, including RAP1GDS1 and LEF1, which may be associated with IFN development. Finally, no significant mutations were found in IFNs using a gene panel.

CONCLUSIONS

The current molecular profiles of IFN may help elucidate the mechanisms of IFN development.

Pathology and Clinical Relevance of Gastric Epithelial Dysplasia

Gastric dysplasia is defined as an unequivocally neoplastic epithelium. Dysplastic lesions are characterized by cellular atypia reflective of abnormal differentiation and disorganized glandular architecture. The last few years have been marked by a refinement of the prognosis and risk of progression of gastric dysplasia and the recognition of novel morphologic patterns of dysplasia. Determination of the correct diagnosis and grade of dysplasia are critical steps since it will be predicting the risk of malignant transformation and help tailor appropriate surveillance strategy. This review describes the morphologic characteristics of conventional dysplasia and nonconventional gastric dysplasia that have been more recently characterized.

Helicobacter pylori Treatment and Gastric Cancer Risk After Endoscopic Resection of Dysplasia: A Nationwide Cohort Study

BACKGROUND & AIMS

The study investigated the association between Helicobacter pylori treatment and the risk of gastric cancer after endoscopic resection of gastric dysplasia.

METHODS

Patients who received endoscopic resection for gastric dysplasia between 2010 and 2020 from Korean nationwide insurance data were included. We verified the occurrence of new-onset gastric cancer and metachronous gastric neoplasm, which encompasses both cancer and dysplasia, >1 year after the index endoscopic resection. Newly diagnosed gastric cancer ≥3 years and ≥5 years was regarded as late-onset gastric cancer. A multivariable Cox regression model with H pylori treatment status as a time-dependent covariate was used to determine the risk of gastric cancer and metachronous gastric neoplasms.

RESULTS

Gastric dysplasia in 69,722 patients was treated with endoscopy, and 49.5% were administered H pylori therapy. During the median 5.6 years of follow-up, gastric cancer developed in 2406 patients and metachronous gastric neoplasms developed in 3342 patients. Receiving H pylori therapy was closely related to lower gastric cancer risk (adjusted hazard ratio [aHR], 0.88; 95% confidence interval [CI], 0.80-0.96). H pylori treatment also significantly decreased metachronous gastric neoplasm development (aHR, 0.76; 95% CI, 0.70-0.82). Furthermore, H pylori therapy showed a prominent protective effect for late-onset gastric cancer development at ≥3 years (aHR, 0.84; 95% CI, 0.75-0.94) and ≥5 years (aHR, 0.80; 95% CI, 0.68-0.95).

CONCLUSIONS

In this nationwide cohort, H pylori therapy after endoscopic resection of gastric dysplasia was associated with a reduced risk of gastric cancer and metachronous gastric neoplasm occurrence.

Histopathological Evaluation of Gastric Mucosal Atrophy for Predicting Gastric Cancer Risk: Problems and Solutions

Patients suffering from chronic gastritis and developing gastric mucosa atrophy are at increased risk of the development of gastric cancer. The diagnosis of chronic atrophic gastritis (CAG) is a complex procedure involving a detailed history taking, a thorough physical examination and the use of laboratory and instrumental diagnostic methods among which the endoscopy of the upper digestive tract is the cornerstone because it allows the assessment of the topography of gastritis and identification of erosions and areas of intestinal metaplasia with the use of NBI endoscopy. However, the diagnosis of CAG requires morphological examination of the gastric mucosa. So, in addition to assessing macroscopic changes in the gastric mucosa, it is necessary to take biopsy specimens in accordance with the protocols for their morphological and immunohistochemical examination. In the absence of specific diagnostic stigmas of CAG, close cooperation between a clinician, endoscopist and pathologist is necessary. The article presents systematized data on the histopathological assessment of the gastric mucosa atrophy to predict the risk of gastric cancer.

Clinical features of gastric adenoma detected within 3 years after negative screening endoscopy in Korea

Background

Early detection and management of gastric adenoma are important for preventing gastric cancer. The present study aimed to evaluate the predictors of missed gastric adenoma on screening endoscopy in Korea and identify the risk factors associated with interval precancerous gastric lesions.

Methods

All cases of gastric adenomas diagnosed via screening endoscopy between 2007 and 2019 were reviewed. Among them, those who had undergone endoscopy within 3 years were included in the present study. Missed gastric adenoma was defined as gastric adenoma diagnosed within 3 years after negative screening endoscopy.

Results

In total, 295 cases of gastric adenoma were identified. Of these, 95 (32.2%) were missed gastric adenoma cases (mean age, 60.6 years; average interval between final and index endoscopies, 12.6 months); the remaining 200 (67.8%) were newly detected adenoma cases. Univariate analysis revealed that male sex, endoscopist experience, observation time, and presence of gastric intestinal metaplasia (pathologically proven) were associated with missed gastric adenoma. Multivariate analysis revealed that gastric intestinal metaplasia (odds ratio [OR], 2.736; 95% confidence interval [CI], 1.320-5.667; P = 0.007) and shorter observation time of the index screening endoscopy (B, -0.011; OR, 0.990; 95% CI, 0.986-0.993; P < 0.001) were independent risk factors for missed gastric adenoma. The optimal cut-off for the observation time for detecting gastric adenoma was 3.53 minutes (area under curve, 0.738; 95% CI, 0.677-0.799; P < 0.001).

Conclusions

Gastric intestinal metaplasia is an indication of missed gastric adenoma. Therefore, careful inspection of gastric mucosa with gastric intestinal metaplasia and proper observation time can lower the possibility of missing the gastric adenoma during screening.

Expression of SASP, DNA Damage Response, and Cell Proliferation Factors in Early Gastric Neoplastic Lesions: Correlations and Clinical Significance

The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING)-mediated senescence-associated secretory phenotype (SASP) pathway has recently been identified in the suppression and promotion of cancers. However, its practical role in carcinogenesis remains to be comprehensively elucidated. Here, we describe an investigation analysing SASP activity and its correlations with DNA damage response (DDR), genomic mutations, and cell proliferation in gastric carcinogenesis among 30 cases with available endoscopic submucosal dissection (ESD) specimens of early neoplastic lesions (including low-grade dysplasia [LGD], high-grade dysplasia [HGD], and intramucosal carcinoma). The positive cells of senescence-associated β-galactosidase staining and cGAS, STING, interferon-regulatory factor 3 (IRF3), and signal transducer and activator of transcription 6 (STAT6) expression levels using immunostaining were elevated in HGD and in cancers. Similarly, increased expression of the Fanconi anemia group D2 (FANCD2) protein, tumour suppressor p53 binding protein 1 (TP53BP1), and replication protein A (RPA2) (i.e., primary DDR factors) was detected in HGD and in cancers; these increased expression levels were closely correlated with high expression of Ki67 and minichromosome maintenance complex component 7 (MCM7) proteins. Moreover, genomic mutations in TP53 gene were detected in 56.67% of the evaluated cases (17/30) using next-generation sequencing, and positive staining was verified in HGD and in cancers. Statistical analysis revealed that cell proliferation closely correlated with the expression of DDR factors, of which TP53BP1 was positively associated with SASP factors and IRF3 was positively correlated with cell proliferation. In addition, an analysis evaluating clinical features demonstrated that STAT6-positive cases showed a longer progression-free survival time than STAT6-negative cases. Our evaluation, conducted using a limited number of specimens, suggests SASP may be prevalent in early gastric neoplastic lesions and could be activated by accelerated cell proliferation-induced DDR. The clinical significance of SASP still needs to be determined.

Academy of Medicine, Singapore clinical guideline on endoscopic surveillance and management of gastric premalignant lesions

Gastric cancer (GC) has a good prognosis, if detected at an early stage. The intestinal subtype of GC follows a stepwise progression to carcinoma, which is treatable with early detection and intervention using high-quality endoscopy. Premalignant lesions and gastric epithelial polyps are commonly encountered in clinical practice. Surveillance of patients with premalignant gastric lesions may aid in early diagnosis of GC, and thus improve chances of survival. An expert professional workgroup was formed to summarise the current evidence and provide recommendations on the management of patients with gastric premalignant lesions in Singapore. Twenty-five recommendations were made to address screening and surveillance, strategies for detection and management of gastric premalignant lesions, management of gastric epithelial polyps, and pathological reporting of gastric premalignant lesions.

Identifying the pre-malignant stomach: from guidelines to practice

Gastric adenocarcinoma develops after stepwise progression from normal mucosa through to adenocarcinoma most commonly after being triggered by Helicobacter pylori (H. pylori) infection. As disease is often diagnosed late, the prognosis for gastric adenocarcinoma is poor. Identifying pre-malignant mucosal lesions such as atrophic gastritis, intestinal metaplasia and dysplasia is one strategy adopted by clinicians to reduce cancer related mortality. Surveillance of high-risk individuals and endoscopic resection of dysplastic lesions is recommended by international and UK guidelines. The early detection and endoscopic management reduce the need for invasive surgery. The advancement of image enhanced endoscopy technology, endoscopic training, risk stratification and histological assessment has proven pivotal to the management of pre-malignant lesions. In this review we outline the development of a high-risk stomach, endoscopic assessment and review practical guidelines on identifying pre-malignant gastric mucosa.

Risk factor-based optimal endoscopic surveillance intervals after endoscopic submucosal dissection for gastric adenoma

To date, there exists no established endoscopic surveillance interval strategy after endoscopic submucosal dissection (ESD) for gastric adenoma. In this study, we suggest a risk factor-based statistical model for optimal surveillance intervals for gastric adenoma after ESD with curative resection. A cox proportional hazard model was applied to identify risk factors for recurrence after ESD. Patients (n = 698) were categorized into groups based on the identified risk factors. The cumulative density of recurrence over time was computed using a cubic splined baseline hazard function, and the customized surveillance interval was modeled for each risk group. The overall cumulative incidence of recurrence was 7.3% (n = 51). Risk factors associated with recurrence were male (hazard ratio [HR], 2.60, P = 0.030), protruded scar (HR, 3.18, P < 0.001), and age ≥ 59 years (HR, 1.05, P < 0.001). The surveillance interval for each group was developed by using the recurrence limit for the generated risk groups. According to the developed schedule, high-risk patients would have a maximum of seven surveillance visits for 5 years, whereas low-risk patients would have biennial surveillance for cancer screening. We proposed a simple and promising strategy for determining a better endoscopic surveillance interval by parameterizing diverse and group-specific recurrence risk factors into a well-known survival model.

Comparative molecular subtypes of index and metachronous gastric adenocarcinomas: a study of 42 Korean patients

To date, there have been no studies comparing the molecular subtypes of Index gastric cancers (IGCs) and metachronous gastric cancers (MGCs). We evaluated a cohort of 42 patients with 43 IGCs and 45 MGCs. Molecular subtyping was performed by immunohistochemistry of mismatch repair (MMR) proteins, E-cadherin, p53, and Epstein-Barr virus- (EBV-) in situ hybridization (ISH). Gastric adenocarcinomas were classified into 5 subtypes: EBV-associated, MMR deficient (MMRD), E-cadherin aberrant, p53-aberrant [p53(+)], and p53 non-aberrant [p53(neg)]. All IGCs had been successfully treated by either surgery (19%) or endoscopic resection (81%). The mean interval between IGCs and MGCs was 85 months. Among the IGCs, EBV-associated, MMRD, E-cadherin-aberrant, p53(+), and p53(neg) molecular subtypes represented 2 (5%), 4 (9%), 2 (5%), 21 (49%), and 14 (32%) of the cases, respectively. Two cases had concomitant p53(+) and aberrant E-cadherin molecular subtypes. Among metachronous cancers, EBV-associated, MMRD, E-cadherin-aberrant, p53(+), and p53(neg) molecular subtypes represented 3 (7%), 11 (24%), 0 (0%), 22 (49%), and 9 (20%) cases. Concomitant p53(+) was observed in 1 EBV-associated and 2 MMRD MGCs. Although, there was no significant difference in the frequency of most molecular subtypes in IGCs and MGCs, the number of MMRD gastric cancers more than doubled in the MGC group. Half of the MGCs had a divergent molecular subtype compared to that of the IGCs. Notably, the interval between the development of IGCs and MGCs was significantly longer in patients with divergent molecular subtypes (P = 0.010). All 4 patients with MMRD IGC developed MMRD MGCs. Although the concept of mucosal field cancerization may explain the matching molecular subtypes in early-developing MGCs, the presence of divergent subtypes in late-occurring MGCs suggests a shift in the carcinogenic mechanism affecting the residual mucosa possibly related to Helicobacter pylori eradication.

Risk factors associated with surveillance loss after endoscopic submucosal dissection in patients with gastric neoplasm

Background

After endoscopic submucosal dissection of gastric neoplasms, surveillance endoscopy is required for patients with synchronous or metachronous neoplasms. We aimed to evaluate the risk factors associated with surveillance loss in patients who underwent endoscopic submucosal dissection.

Methods

Ninety-five patients treated with endoscopic submucosal dissection for gastric neoplasms between May 2015 and June 2016 were retrospectively reviewed. Clinicopathologic factors, sociodemographic factors, psychiatric measures, and associated risk factors for surveillance loss were evaluated. The chi-square or Fisher exact test, t-test, and logistic regression analysis were used in data analysis.

Results

Twenty-five (26.3%) patients were identified as having surveillance loss. Compared to the surveillance group, the surveillance loss group was old and had dysplasia, and a healthy American Society of Anesthesiologists physical status. Similarly, surveillance loss was related to low symptom perception, low incidence of alexithymia, mindful awareness, and high trait forgiveness. Logistic regression analysis showed that dysplasia (odds ratio, 15.23; 95% CI, 1.56-149.09, P=0.019), old age (odds ratio, 7.14; 95% CI, 1.90-26.88, P=0.004), and American Society of Anesthesiologists physical status 1 (odds ratio, 3.99; 95% CI, 1.09-14.60, P=0.037) were associated with surveillance loss.

Conclusions

Dysplasia, old age, and the American Society of Anesthesiologists physical status 1 were associated with surveillance loss in patients who underwent gastric endoscopic submucosal dissection. It could be helpful to proactively monitor patients with such conditions after gastric endoscopic submucosal dissection.

Gastric dysplasia causing gastric outlet obstruction

Gastric dysplasia signifies the presence of atypical cells in the gastric mucosa, which have not invaded beyond the lamina propria, and it rarely leads to tissue growth large enough to cause gastric outlet obstruction (GOO) to the gastric contents. However, GOO is commonly observed as a first clinical manifestation of advanced invasive gastric cancer in developing countries where patients seek medical care late. The present case highlights the treatment journey of a young woman who presented to us with features of GOO. Her endoscopic and radiological findings revealed a nodular gastric antral thickening causing GOO. An endoscopic biopsy showed features of dysplasia. She underwent distal gastrectomy following discussion in a multidisciplinary tumour board. Histopathological examination of the gastrectomy specimen confirmed dysplasia without any invasion beyond lamina. To the best of our knowledge, this is perhaps the first report of dysplasia of the stomach presenting as GOO.

Long-term natural history after endoscopic resection for gastric dysplasia

BACKGROUND AND STUDY AIMS

Natural history after endoscopic resection (ER) for gastric dysplasia is still unclear. The aim of this study was to evaluate the long-term clinical outcomes and risk factors after ER for gastric dysplasia between control and cases with synchronous or metachronous gastric neoplasm.

METHODS

A total of 1090 patients who had undergone ER for gastric dysplasia and been followed up for at least one year from December 2002 to December 2013 were finally analyzed. Risk factors affecting the development of synchronous or metachronous neoplasm (SMN) and long-term clinical outcomes after ER for gastric dysplasia were evaluated.

RESULTS

Synchronous and metachronous neoplasms had developed in 126 (11.6%) and 133 patients (12.2%) during the mean follow-up duration of 63.6 months, respectively. Five-year and 10-year risk of metachronous neoplasm were 9.8% and 27.2%, respectively. Median duration to the development of metachronous neoplasm was 103.1 months. While age (P < 0.001) and mucosal atrophy (P = 0.09) of index cases were associated with the development of synchronous neoplasm, age (P = 0.017), incomplete resection (P = 0.025), and intestinal metaplasia (P = 0.017) of background mucosa of index cases were significantly related to the development of metachronous neoplasm in multivariate analysis. Cumulative incidence of SMN was not significantly different among H. pylori negative, eradicated, and persistent group.

CONCLUSIONS

Age, incomplete ER, and background intestinal metaplasia of index gastric dysplasia were significantly associated with metachronous recurrence. Endoscopic surveillance for metachronous recurrence after ER for gastric dysplasia is mandatory for longer than 10 years.

A Systematic Review of the Mechanisms Underlying Treatment of Gastric Precancerous Lesions by Traditional Chinese Medicine

Gastric precancerous lesions (GPLs) are an essential precursor in the occurrence and development of gastric cancer, known to be one of the most common and lethal cancers worldwide. Traditional Chinese medicine (TCM) has a positive prospect for the prevention and therapy of GPL owing to several advantages including a definite curative effect, fewer side effects compared to other treatments, multiple components, and holistic regulation. Despite these characteristic advantages, the mechanisms of TCM in treating GPL have not been fully elucidated. In this review, we summarize the current knowledge with respect to herbal formulations and the therapeutic mechanisms of TCM active ingredients for GPL. This paper elaborates on the mechanisms of TCM underlying the prevention and treatment of GPL, specifically those that are linked to anti-H. pylori, anti-inflammation, antiproliferation, proapoptotic, antioxidation, antiglycolytic, and antiangiogenesis effects.

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

Gastric adenocarcinoma carries a poor prognosis, in part due to the late stage of diagnosis. Risk factors include Helicobacter pylori infection, family history of gastric cancer-in particular, hereditary diffuse gastric cancer and pernicious anaemia. The stages in the progression to cancer include chronic gastritis, gastric atrophy (GA), gastric intestinal metaplasia (GIM) and dysplasia. The key to early detection of cancer and improved survival is to non-invasively identify those at risk before endoscopy. However, although biomarkers may help in the detection of patients with chronic atrophic gastritis, there is insufficient evidence to support their use for population screening. High-quality endoscopy with full mucosal visualisation is an important part of improving early detection. Image-enhanced endoscopy combined with biopsy sampling for histopathology is the best approach to detect and accurately risk-stratify GA and GIM. Biopsies following the Sydney protocol from the antrum, incisura, lesser and greater curvature allow both diagnostic confirmation and risk stratification for progression to cancer. Ideally biopsies should be directed to areas of GA or GIM visualised by high-quality endoscopy. There is insufficient evidence to support screening in a low-risk population (undergoing routine diagnostic oesophagogastroduodenoscopy) such as the UK, but endoscopic surveillance every 3 years should be offered to patients with extensive GA or GIM. Endoscopic mucosal resection or endoscopic submucosal dissection of visible gastric dysplasia and early cancer has been shown to be efficacious with a high success rate and low rate of recurrence, providing that specific quality criteria are met.

Endoscopic management of patients with early gastric cancer before and after endoscopic resection: A review

With the wide application of endoscopic resection for early gastric cancer (EGC) by not only Asian endoscopists but also those from Western countries, reviews on standardized treatment processes before and after endoscopic resection are nevertheless lacking. In this article we provide a narrative review of studies on the selection of appropriate EGC for endoscopic resection and the follow-up strategies for those with histologically confirmed EGC after endoscopic resection. EGC should be comprehensively assessed before endoscopic resection, including its exact margin, invasive depth and risk of lymph node metastasis (LNM). While the curative resection status of EGC may be evaluated after endoscopic resection based on the newly developed eCura system, although this needs to be further verified. Surveillance with endoscopy and computed tomography scan is necessary for patients with an EGC level A or B. An additional endoscopic resection is recommended for patients with a level-C1 EGC. For patients with a level-C2 EGC, close follow-up is suggested for low-risk tumors of level C2 and additional surgery for those at high risks. Further postoperative strategy is suggested based on comprehensive assessment of the risk of LNM, patient's quality of life and wishes.

Incidence Rate of Gastric Cancer Adenocarcinoma in Patients With Gastric Dysplasia: A Systematic Review and Meta-Analysis

Several studies have reported the risk of progression to gastric adenocarcinoma (GAC) in patients with gastric dysplasia (GD); however, the findings are controversial. We performed a systematic review and meta-analysis to study the incidence rate of GAC among patients with GD. Using a comprehensive search strategy, we systematically searched online databases including PubMed, Scopus, EMBASE, Cochrane Library, and Web of Science databases for identifying all relevant original articles through inception until July 2018. Cochran Q and I tests were used to assess heterogeneities between included studies. The incidence rates of GAC and their corresponding 95% confidence intervals (CIs) were pooled using random-effect or fixed-effect models. Of the 1980 retrieved records, 30 eligible articles (61 studies) were included. The overall pooled incidence rate of GAC was 40.36 (95% CI, 27.08-55.71; I, 96.0%) cases per 1000 person-years in patients with GD. Subgroup analysis according to the type of GD indicated the highest incidence rate of GAC was 186.40 (95% CI, 106.63-285.60; I, 94.6%) per 1000 person-years among patients with high-grade dysplasia (HGD) lesions. Although the incidence rates of GAC in low-grade dysplasia (LGD) lesions and in nonclassified lesions were 11.25 (95% CI, 3.91-21.22; I, 89.3%), and 1.40 (95% CI, 0.00-9.71; I, 78.8%), respectively. Compared with patients with LGD lesions, progression rate from GD to GAC was roughly 16 times greater in patients with HGD lesions. As the majority of patients with GAC are diagnosed in an advanced stage our study suggests strict management of HGD lesions to prevent GAC.

XZ-1 regulates cell apoptosis of gastric epithelial dysplasia via NF-κB/p53/Ki67 signaling pathway

We aimed to determine the effect of ‘Xiaozeng No. 1’ (XZ-1) on cellular apoptosis changes of gastric epithelial dysplasia (GED) and to explore the underlying mechanism. Specimens taken from the pyloric area of the stomachs from rats in each group were subjected to Hematoxylin and Eosin (H&E) staining for pathological examination, TUNEL staining for apoptosis detection, and Western blot analysis for apoptosis-related proteins. The results showed that XZ-1 decreased GED incidence and enhanced gastric epithelial apoptosis. Furthermore, XZ-1 up-regulated the proapoptotic proteins including cleaved caspases (cysteine-dependent aspartate-specific protease) (-3, -8, and -9), Fas, Bax, and Bid, and facilitated the release of cytochrome c from mitochondria to the cytoplasm. Interestingly, XZ-1 enhanced protein expression of NF-κB p65, Ki67, and p53. Moreover, inhibition of NF-κB pathway suppressed the XZ-induced p53 expression, whereas inhibition of NF-κB or p53 pathway suppressed the XZ-induced Ki67. More importantly, inhibition of NF-κB or p53 pathway attenuated the XZ-1-mediated induction of gastric epithelial apoptosis and decline of GED incidence. Collectively, our results demonstrated that XZ-1, almost equivalent effect exerted by the positive control Retin-A, dramatically decreased GED incidence and enhanced gastric epithelial apoptosis. Meanwhile, XZ-1 activated the NF-κB/p53/Ki67-apoptosis signaling pathway, which might be one of the mechanisms whereby XZ-1 reversed GED.

Occurrence of metachronous or synchronous lesions after endoscopic treatment of gastric epithelia dysplasia- impact of histologic features of background mucosa

AIMS

Endoscopic resection is a safe and effective method to treat gastric epithelia dysplasia (GED). However, the development of metachronous and synchronous lesions after treatment has become a major concern. In this study, we investigated clinicopathologic features of 105 GED lesions from endoscopic resections between January 2008 and December 2009. Our goal is to find histologic factors that predict synchronous and metachronous lesions after ESD treatment. We assessed the degree of intestinal metaplasia (IM) and atrophy, type of IM, presence of gastritis cystica profunda, and crypt dysplasia in the adjacent mucosa.

METHODS AND RESULTS

We divided 105 GED lesions into three groups: a single group without metachronous or synchronous GED or adenocarcinoma (n=35); a multiple synchronous group (n=30, group with synchronous occurrence of GED or adenocarcinoma after treatment); and a multiple metachronous group (n=40, group with metachronous occurrence of GED or adenocarcinoma after treatment). The multiple metachronous and synchronous groups showed larger sizes (p=0.003) and higher grades (p=0.021) as compared with the single group. Furthermore, marked IM and atrophy in adjacent mucosa were more easily seen in the multiple metachronous and synchronous groups as compared with the single group (p<0.0001). Interestingly, the presence of incomplete type of IM (p=0.025) and crypt dysplasia (p<0.0001) in background mucosa was associated with occurrence of metachronous and synchronous lesions following endoscopic resection of GED.

CONCLUSIONS

The histological features of background mucosa, such as intestinal metaplasia, atrophy, and crypt dysplasia could be used as indicators of occurrence of metachronous and synchronous lesions after endoscopic treatment of GED.

Risk factors for metachronous gastric carcinoma development after endoscopic resection of gastric dysplasia: Retrospective, single-center study

AIM

To determine the gastric adenocarcinoma (GAC) occurrence rate and related factors, we evaluated the follow-up results of patients confirmed to have gastric dysplasia after endoscopic resection (ER).

METHODS

We retrospectively analyzed the medical records, endoscopic examination records, endoscopic procedure records, and histological records of 667 cases from 641 patients who were followed-up for at least 12 mo, from among 1273 patients who were conformed to have gastric dysplasia after Endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) of gastric mucosal lesions between January 2007 and August 2013 at the Chungnam National University Hospital.

RESULTS

The mean follow-up period was 33.8 mo, and the median follow-up period was 29 mo (range: 12-87). During the follow-up period, the occurrence of metachronous GAC was 4.0% (27/667). The mean and median interval periods between the occurrence of metachronous GAC and endoscopic treatment of gastric dysplasia were 36.3 and 34 mo, respectively (range: 16-71). The factors related to metachronous GAC occurrence after ER for gastric dysplasia were male sex (5.3% vs 1.0%), open-type atrophic gastritis (9.5% vs 3.4%), intestinal metaplasia (6.8% vs 2.4%), and high-grade dysplasia (HGD; 8.4% vs 3.2%). Among them, male sex [OR: 5.05 (1.18-21.68), P = 0.029], intestinal metaplasia [OR: 2.78 (1.24-6.23), P = 0.013], and HGD [OR: 2.70 (1.16-6.26), P = 0.021] were independent related factors in multivariate analysis. Furthermore, 24 of 27 GAC cases (88.9%) occurred at sites other than the previous resection sites, and 3 (11.1%) occurred at the same site as the previous resection site.

CONCLUSION

Male sex, intestinal metaplasia, and HGD were significantly related to the occurrence of metachronous GAC after ER of gastric dysplasia, and most GACs occurred at sites other than the previous resection sites.

Endoscopic Submucosal Dissection of Gastric Epithelial Neoplasms after Partial Gastrectomy: A Single-Center Experience

AIMS

To investigate the feasibility and safety of endoscopic submucosal dissection (ESD) of gastric epithelial neoplasms in the remnant stomach (GEN-RS) after various types of partial gastrectomy.

METHODS

This study included 29 patients (31 lesions) who underwent ESD for GEN-RS between March 2006 and August 2016. Clinicopathologic data were retrieved retrospectively to assess the therapeutic ESD outcomes, including en bloc and complete resection rates and procedure-related adverse events.

RESULTS

The en bloc, complete, and curative resection rates were 90%, 77%, and 71%, respectively. The types of previous gastrectomy, tumor size, macroscopic type, and tumor histology were not associated with incomplete resection. Only tumors involving the suture lines from the prior partial gastrectomy were significantly associated with incomplete resection. The procedure-related bleeding and perforation rates were 6% and 3%, respectively; none of the adverse events required surgical intervention. During a median follow-up period of 25 months (range, 6-58 months), there was no recurrence in any case.

CONCLUSIONS

ESD is a safe and feasible treatment for GEN-RS regardless of the previous gastrectomy type. However, the complete resection rate decreases for lesions involving the suture lines.

Gastric foveolar dysplasia: a survey of reporting habits and diagnostic criteria

This study aimed to ascertain views, incidence of reporting and diagnostic criteria for gastric foveolar dysplasia. A questionnaire, a post-questionnaire discussion and microscopic assessment of selected cases was conducted by gastrointestinal pathologists to explore the above-stated aims. Fifty-four percent of respondents never or rarely diagnosed gastric foveolar-type dysplasia. The general consensus was that round nuclei, lack of nuclear stratification, presence of inflammation/damage and surface maturation favoured reactive change; while architectural abnormalities/complexity and nuclear enlargement mainly were used to separate low-grade from high-grade foveolar dysplasia. Immunohistochemistry was rarely used to make the diagnosis of dysplasia and was thought not to be of help in routine practice. Inter-observer agreement in grading of dysplasia versus reactive, and the type of dysplasia (foveolar versus adenomatous), was substantial/almost perfect amongst 35.7% and 21.4% of participants, respectively. This reflects low reproducibility in making these diagnoses. In conclusion, foveolar dysplasia was a rarely made diagnosis among 14 gastrointestinal pathologists, there are no uniform criteria for diagnosis and there is poor inter-observer agreement in separating low-grade foveolar dysplasia from reactive gastric mucosa and low-grade adenomatous dysplasia. Greater awareness and agreed criteria will prevent misdiagnosis of low-grade foveolar dysplasia as reactive, and vice versa.

Role of targeted biopsy under magnifying endoscopy with narrow band imaging may be not necessary: a prospective diagnostic accuracy study

BACKGROUND AND AIMS

Targeted biopsy under the guidance of magnifying endoscopy with narrow band imaging (ME-NBI) has higher accuracy than endoscopic forceps biopsy (EFB) in the differential diagnosis of cancerous lesions from noncancerous lesions. The aims of this study were to validate diagnostic efficacy of targeted biopsy under the guidance of ME-NBI (MNTB) and further evaluate whether it is necessary to perform MNTB when combined with ME-NBI.

METHODS

This study prospectively analyzed 211 gastric lesions of suspected cancerous tissues. The sensitivity, specificity, positive predictive value, and negative predictive value of EFB, ME-NBI, MNTB, EFB plus ME-NBI, and MNTB plus ME-NBI for the diagnosis of cancerous lesions were determined, respectively. The accuracy, sensitivity, specificity of EFB and MNTB, EFB plus ME-NBI, and MNTB plus ME-NBI were also compared, respectively.

RESULTS

The accuracy, sensitivity, and specificity with 95% confidence intervals were 68.2% (61.4-74.4%), 62.3% (54.1-69.9%), 84.2% (71.6-92.1%) for EFB, 75.4% (68.9-80.9%), 72.7% (64.9-79.4%), 82.5% (69.6-90.8%) for MNTB, 76.8% (70.4-82.2%), 73.4% (65.5-80.0%), 86.0% (73.7-93.3%) for ME-NBI, 82.0% (76.0-86.8%), 85.7% (79.0-90.6%), 71.9% (58.3-82.6%) for EFB plus ME-NBI, 84.8% (79.1-89.3%), 89.6% (83.4-93.8%), and 71.9% (58.3-82.6%) for MNTB plus ME-NBI, respectively. The sensitivity of MNTB was significantly higher than that of EFB (P=0.048). There was no significant difference in the sensitivity (P=0.307), specificity (P=1.000), and accuracy (P=0.337) between EFB plus ME-NBI and MNTB plus ME-NBI.

CONCLUSION

Although MNTB has a higher diagnostic efficacy than EFB in the diagnosis of cancerous lesions, it may be not necessary to perform MNTB when combined with ME-NBI.

A Previously Undescribed Presentation of Mixed Adenoneuroendocrine Carcinoma

We report a case of mixed adenoneuroendocrine carcinoma (MANEC) of stomach with tubular adenoma and well-differentiated neuroendocrine tumor (WD-NET) in the primary tumor in the stomach giving rise to biphenotypic regional nodal metastases. A 35-year-old woman with abdominal pain was found to have a 1.8-cm gastric lesion, diagnosed as WD-NET (intermediate grade) on the biopsy. The resection specimen contained residual WD-NET; there was also a gastric adenoma adjacent to the NET and nodal metastasis with both adeno- and neuroendocrine components. The tumor was classified as MANEC. Of note, the entire gastric tissue was submitted and multiple deeper levels of the adenomatous lesion were examined; no adenocarcinoma was present in the primary lesion. While association of gastric adenoma with neuroendocrine neoplasm is rare, presence of biphenotypic metastasis originating from such a lesion is highly unusual and to the best of our knowledge has not been reported.