Effectiveness of systematic alphanumeric coded endoscopy for diagnosis of gastric intraepithelial neoplasia in a low socioeconomic population

A new, simplified endoscopic scoring system for predicting clinical outcome in gastric low-grade intraepithelial neoplasia: the "e-cout system"

BACKGROUND AND OBJECTIVES

The clinical outcomes of gastric low-grade intraepithelial neoplasia (LGIN) exhibit significant diversity, and the current reliance on endoscopic biopsy for diagnosis poses limitations in devising appropriate treatment strategies for this disease. This study aims to establish a prognostic prediction scoring system (e-Cout system) for gastric LGIN, offering a theoretical foundation for solving this clinical challenge.

METHODS

Retrospectively selecting 1013 cases meeting the inclusion and exclusion criteria from over 300,000 cases of upper gastrointestinal endoscopy performed at the Digestive Endoscopy Center of our hospital between 2000 and 2022, the cohort included 484 cases as development cohort and 529 cases for validation. Employing relevant statistical analysis, we used development cohort data to establish the e-Cout system for gastric LGIN, and further used validation cohort data to for internal validation.

RESULTS

In the developmental stage, based on accordant regression coefficients, we assigned point values to six risk factors for poor prognosis: 4 points for microvessel (MV) distortion, 3 points for MV thickening, 2 points for ulcer, and 1 point each for lesion size > 2cm, disease duration > 1 year, and hyperemia and redness on the lesion surface. Patients were then categorized into four risk levels: low risk (0-1 point), medium risk (2-3), high risk (4-6), and very high risk (≥7). During the validation stage, significant differences in the three different outcomes of gastric LGIN were observed across all risk levels. The probability of reversal and progression showed a significant decrease and increase, respectively, with escalating of risk levels, and these differences were statistically significant (P< 0.001).

CONCLUSIONS

The proposed e-Cout system holds promise in aiding clinicians to predict the probability and risk levels of different clinical outcomes in patients with gastric LGIN. This system is expected to provide an improved foundation and guidance for the selection of clinical strategies for this disease.

Endoscopic causes and characteristics of missed gastric cancers after endoscopic submucosal dissection

BACKGROUND AND AIMS

Because endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) preserves the entire stomach, missed gastric cancers (MGCs) are often found in the remaining gastric mucosa. However, the endoscopic causes of MGCs remain unclear. Therefore, we aimed to elucidate the endoscopic causes and characteristics of MGCs after ESD.

METHODS

From January 2009 to December 2018, all patients undergoing ESD for initially detected EGC were enrolled. According to a review of EGD images before ESD, we identified the endoscopic causes (perceptual, exposure, sampling errors, and inadequate preparation) and characteristics of MGC in each endoscopic cause.

RESULTS

Of 2208 patients who underwent ESD for initial EGC, 82 patients (3.7%) had 100 MGCs. The breakdown of endoscopic causes of MGCs was as follows: 69 (69%) perceptual errors, 23 (23%) exposure errors, 7 (7%) sampling errors, and 1 (1%) inadequate preparation. Logistic regression analysis showed that the risk factors for perceptual error were male sex (odds ratio [OR], 2.45; 95% confidence interval [CI], 1.16-5.18), isochromatic coloration (OR, 3.17; 95% CI, 1.47-6.84), greater curvature (OR, 2.31; 95% CI, 1.121-4.40), and lesion size ≤12 mm (OR, 1.74; 95% CI, 1.07-2.84). The sites of exposure errors were around the incisura angularis (11 [48%]), posterior wall of the gastric body (6 [26%]), and antrum (5 [21%]).

CONCLUSIONS

We identified MGCs in 4 categories and clarified their characteristics. Quality improvements in EGD observation, with attention to the risks of perceptual and site of exposure errors, can potentially prevent missing EGCs.

Controlling Gastric Cancer in a World of Heterogeneous Risk

Gastric cancer (GC) is a leading cause of global mortality but also a cancer whose footprint is highly unequal. This review aims to define global disease epidemiology, critically appraise strategies of prevention and disease attenuation, and assess how these strategies could be applied to improve outcomes from GC in a world of variable risk and disease burden. Strategies of primary prevention focus on improving the detection and eradication of the main environmental risk factor, Helicobacter pylori. In certain countries of high incidence, endoscopic or radiographic screening of the asymptomatic general population has been adopted as a means of secondary prevention. By contrast, identification and targeted surveillance of individuals with precancerous lesions (such as intestinal metaplasia) is being increasingly embraced in nations of low incidence. This review also highlights existing knowledge gaps in GC prevention as well as the role of emerging technologies for early detection and risk stratification.

Role of artificial intelligence-guided esophagogastroduodenoscopy in assessing the procedural completeness and quality

BACKGROUND AND AIMS

The quality of esophagogastroduodenoscopy (EGD) can have great impact on the detection of esophageal and gastric lesions, including malignancies. The aim of the study is to investigate the use of artificial intelligence (AI) during EGD by the  endoscopists-in-training so that a real-time feedback can be provided, ensuring compliance to a pre-decided protocol for examination.

METHODS

This is an observational pilot study. The videos of the EGD procedure performed between August 1, 2021, and September 30, 2021, were prospectively analyzed using AI system. The assessment of completeness of the procedure was done based on the visualizsation of pre-defined 29 locations. Endoscopists were divided into two categories - whether they are in the training period (category A) or have competed their endoscopy training (category B).

RESULTS

A total of 277 procedures, which included 114 category-A and 163 category-B endoscopists, respectively, were included. Most commonly covered areas by the endoscopists were greater curvature of antrum (97.47%), second part of duodenum (96.75%), other parts of antrum such as the anterior, lesser curvature and the posterior aspect (96.75%, 94.95%, and 94.22%, respectively). Commonly missed or inadequately seen areas were vocal cords (99.28%), epiglottis (93.14%) and posterior, anterior, and lateral aspect of incisura (78.70%, 73.65%, and 73.53%, respectively). The good quality procedures were done predominantly by categoryB endoscopists (88.68% vs. 11.32%, p < 0.00001).

CONCLUSION

AI can play an important role in assessing the quality and completeness of EGD and can be a part of training of endoscopy in future.

Recent advances in diagnostic upper endoscopy

BACKGROUND

Esophageo-gastro-duodenoscopy (EGD) is an important procedure used for detection and diagnosis of esophago-gastric lesions. There exists no consensus on the technique of examination.

AIM

To identify recent advances in diagnostic EGDs to improve diagnostic yield.

METHODS

We queried the PubMed database for relevant articles published between January 2001 and August 2019 as well as hand searched references from recently published endoscopy guidelines. Keywords used included free text and MeSH terms addressing quality indicators and technological innovations in EGDs. Factors affecting diagnostic yield and EGD quality were identified and divided into the follow segments: Pre endoscopy preparation, sedation, examination schema, examination time, routine biopsy, image enhanced endoscopy and future developments.

RESULTS

We identified 120 relevant abstracts of which we utilized 67 of these studies in our review. Adequate pre-endoscopy preparation with simethicone and pronase increases gastric visibility. Proper sedation, especially with propofol, increases patient satisfaction after procedure and may improve detection of superficial gastrointestinal lesions. There is a movement towards mandatory picture documentation during EGD as well as dedicating sufficient time for examination improves diagnostic yield. The use of image enhanced endoscopy and magnifying endoscopy improves detection of squamous cell carcinoma and gastric neoplasm. The magnifying endoscopy simple diagnostic algorithm is useful for diagnosis of early gastric cancer.

CONCLUSION

There is a steady momentum in the past decade towards improving diagnostic yield, quality and reporting in EGDs. Other interesting innovations, such as Raman spectroscopy, endocytoscopy and artificial intelligence may have widespread endoscopic applications in the near future.

Principles and practice to facilitate complete photodocumentation of the upper gastrointestinal tract: World Endoscopy Organization position statement

Although esophagogastroduodenoscopy (EGD) is the most commonly used procedure in the gastrointestinal (GI) tract, the method of esophageal, gastric and duodenal mucosa photodocumentation varies considerably worldwide. One probable explanation is that for generations, EGD has primarily been taught by GI faculty and instructors based on their perceptions and experience, which has resulted in EGD being a non-standardized procedure. Currently, the procedure is facing a challenging scenario as endoscopy societies are implementing procedure-associated quality indicators aiming for best practice among practitioners and evidence-based care for patients. Contrary to colonoscopy where cecum landmarks photodocumentation is considered proof of completeness, there are currently no reliable performance measures to gauge the completeness of an upper endoscopy nor guidance for complete photodocumentation. This World Endoscopy Organization (WEO) position statement aims to provide practical guidance to practitioners to carry out complete EGD photodocumentation. Hence, an international group of experts from the WEO Upper GI Cancer Committee formulated the following document using the body of evidence established through literature reviews, expert opinions, and other scientific sources. The group acknowledged that although the procedure should be feasible in any facility, what is needed to achieve a global shift on the concept of completeness is a common written statement of agreement on its potential impact and added value. This best practice statement offers endoscopists principles and practical guidance in order to carry out complete photodocumentation from the hypopharynx to the second duodenal portion.

Gastric cancer missed at esophagogastroduodenoscopy in a well-defined Spanish population

BACKGROUND

Although esophagogastroduodenoscopy (EGD) is the standard procedure for the diagnosis of gastric cancer (GC), some GCs are missed. There are no published data on the missed rate of GC in Spain.

AIMS

To determine the frequency and characteristics of missed GCs and assess the quality of the EGD in a specific population with GC.

METHODS

Records of all patients diagnosed with gastric adenocarcinoma between 2012 and 2016 in a defined geographic area were reviewed. Missed GC was defined as a case with a prior negative EGD for cancer. Quality indicators from the prior EGDs were measured.

RESULTS

From 212 cases of GC, 25 cases were excluded. Seventeen out of 187 patients had a prior EGD (9.1%). Twelve of those 17 missed GC had a prior EGD with some abnormal findings. In 6 of them, biopsies were taken. Survival was no different between patients with missed and non-missed GC. Quality indicators that failed to meet standards were recording time, image documentation, and a protocol of biopsies.

CONCLUSIONS

Missed GC in an EGD in a defined population in Spain is not uncommon (9.1%). The endoscopist is an important factor in missed GC due to lack of adequate detection and sampling error. Compliance with performance of quality indicators could reduce missed GC.

Update on the Diagnosis and Management of Gastric Intestinal Metaplasia in the USA

Gastric intestinal metaplasia (GIM) is a premalignant condition that can lead to intestinal-type gastric adenocarcinoma. It is characterized by a change in the gastric mucosa to a small-intestinal phenotype. Infection with Helicobacter pylori is the most common factor associated with GIM. Although GIM is typically a histologic diagnosis, various techniques have been developed to enable the endoscopic identification of GIM. There are presently no widely accepted guidelines on screening and surveillance strategies in patients with GIM in the USA. The aim of this review is to provide an update regarding the problem, diagnosis, and management of GIM in the USA.

Linked color imaging improves the endoscopic visibility of gastric mucosal cancers

Background and study aims  As a newly developed endoscopy technique, linked color imaging (LCI) provides very bright images with enhanced color tones. With the objective of improving the detection rate of gastric mucosal cancers, which are often difficult to detect, we examined the utility of LCI from the viewpoint of visibility. Patients and methods  The current study used 100 consecutive gastric mucosal cancers ≤ 20 mm in diameter. For each lesion, we selected one endoscopic image acquired by white-light imaging (WLI), blue-laser imaging (BLI) -bright, and LCI modes. Four endoscopists interpreted the images; using a previously reported scale, we scored the visibility level on a scale of 1 - 4. Results  The mean (± SD) visibility scores were 2.54 ± 1.10 for WLI, 3.02 ± 1.07 for BLI-bright, and 3.28 ± 0.97 for LCI. The score was significantly higher for BLI-bright compared with WLI ( P  < .001) and again higher for LCI compared with BLI-bright ( P  < .001). For the experts, the scores for BLI-bright and LCI were similar, but both were significantly higher than the score for WLI. For the trainees, there was no significant difference between the WLI and BLI-bright scores, but LCI score was significantly higher than those for WLI and BLI-bright scores. With regard to clinical characteristics, LCI particularly enhanced visibility of normochromic, flat and depressed lesions, which had the lowest visibility scores of all three modalities compared with those of the other lesions. Conclusion  LCI increased visibility and may contribute to early detection of gastric mucosal cancers.

Endoscopic Screening in Asian Countries Is Associated With Reduced Gastric Cancer Mortality: A Meta-analysis and Systematic Review

BACKGROUND & AIMS

It is not clear how endoscopic screening for gastric cancer affects incidence or mortality. We performed a systematic review and meta-analysis to evaluate the relationship between endoscopic screening for gastric cancer and mortality and incidence.

METHODS

We conducted a systematic search of PubMed and EMBASE for published cohort and case-control studies of adults without gastric cancer who underwent endoscopic screening at least once that included a comparator and reported outcomes of mortality or incidence through March 8, 2018. Two investigators independently reviewed the included studies and extracted relevant data. The effect estimate of interest was the relative risk (RR). We used a random effects model to combine RRs and 95% confidence intervals (Cis).

RESULTS

Our final analysis included 6 cohort studies and 4 nested case-control studies comprising 342,013 individuals, all from Asia. The combined result (RR, 0.60; 95% CI, 0.49-0.73) indicated that endoscopic screening was associated with a 40% RR reduction in gastric cancer mortality. We did not observe an association between endoscopic screening and incidence (RR, 1.14; 95% CI, 0.93-1.40). Subgroup analysis showed significant reductions in gastric cancer mortality after endoscopic screening compared with no screening (RR, 0.58; 95% CI, 0.48-0.70) or radiographic screening (RR, 0.33; 95% CI, 0.12-0.91). However, endoscopic screening did not significantly reduce mortality compared with expected deaths (RR, 0.67; 95% CI, 0.38-1.16).

CONCLUSIONS

In a systematic review and meta-analysis, we found that endoscopic screening may reduce the risk of death from gastric cancer and not affect incidence in Asian countries. Population-based prospective cohort studies are warranted to confirm our findings.

Linked colour imaging benefits the endoscopic diagnosis of distal gastric diseases

Gastric diseases are common in China, and gastroduodenoscopy could provide accurate diagnoses. Our previous study verified that linked colour imaging (LCI) can improve endoscopic diagnostic accuracy. This study aimed for the first time to establish an LCI-based endoscopic model called colour-microstructure-vessel (CMV) criteria and validated its clinical feasibility for detecting distal gastric diseases manifested as red mucosal lesions under endoscopy in a cohort of 62 patients. Colour features were extracted from the endoscopic images and categorized into 3 types. Colour type 1 was a typical red; Colour type 2 was red ringed with purple and Colour type 3 was red with yellow in the centre and purple around the periphery, allowing for predicting chronic nonatrophic gastritis, chronic atrophic gastritis and gastric cancer. The sensitivity, specificity and Youden index of Colour type 3 with abnormal M or V for gastric cancer were 100.0%, 98.2% and 98.2%. The kappa values for intra-observer and inter-observer agreement for predicting the pathology were 0.834 and 0.791 for experienced endoscopists and 0.788 and 0.732 for endoscopy learners, and these values were comparable regardless of the experience of the endoscopists (P > 0.05). These findings support that the CMV criteria are a promising model for accurate endoscopic diagnosis.