When do we miss synchronous gastric neoplasms with endoscopy?

Risk factors of missed early gastric cancer in endoscopic resected population: a retrospective, case-control study

BACKGROUND

Missed early gastric cancer (MEGC) is prevalent during esophagogastroduodenoscopy (EGD), which is the first-line recommended strategy for detecting early gastric cancer (EGC). Hence, we explored the risk factors for MEGC and different types of MEGC, based on the endoscopic resected population.

METHODS

This retrospective, case-control study was conducted at Nanjing Drum Tower Hospital (NJDTH). We included patients who were diagnosed with EGC during screening EGD, underwent endoscopic resection, and were confirmed by postoperative pathology at the NJDTH from January 2014 to December 2021, and classified them into different types according to the different root causes of misses. Univariable, multivariable, subgroup and propensity score analyses were used to explore the risk factors for MEGC and different types of MEGC.

RESULTS

A total of 447 patients, comprising 345 with initially detected early gastric cancer (IDEGC) and 102 with MEGC, were included in this study. Larger size (≥ 1 cm) (OR 0.45, 95% CI 0.27-0.74, P = 0.002) and invasion depth of submucosa (OR 0.26, 95% CI 0.10-0.69, P = 0.007) were negatively associated with MEGC. Use of sedation (OR 0.32, 95% CI 0.20-0.52, P < 0.001) and longer observation time (OR 0.60, 95% CI 0.37-0.96, P = 0.034) exhibited protective effect on MEGC.

CONCLUSIONS

Smaller and more superficial EGC lesions are more susceptible to misdiagnosis. The use of sedation and prolonged observation time during EGD could help reduce the occurrence of MEGC.

The standardized training and assessment system for magnetically controlled capsule gastroscopy (with video)

BACKGROUND AND AIM

To explore the feasibility of a standardized training and assessment system for magnetically controlled capsule gastroscopy (MCCG).

METHODS

The results of 90 trainees who underwent the standardized training and assessment system of the MCCG at the First Affiliated Hospital of Xi'an Jiaotong University from May 2020 to November 2023 was retrospectively analyzed. The trainees were divided into three groups according to their medical backgrounds: doctor, nurse, and non-medical groups. The training and assessment system adopted the '7 + 2' mode, seven days of training plus two days of theoretical and operational assessment. The passing rates of theoretical, operational, and total assessment were the primary outcomes. Satisfaction and mastery of the MCCG was checked.

RESULTS

Ninety trainees were assessed; theoretical assessment's passing rates in the three groups were 100%. The operational and total assessment passing rates were 100% (25/25), 97.92% (47/48), and 94.12% (16/17), for the doctor, nurse, and non-doctor groups respectively, with no significant difference (χ2 = 1.741, p = 0.419). No bleeding or perforation occurred during the procedure. Approximately, 96.00% (24/25), 95.83% (46/48), and 94.12% (16/17) of the doctor, nurse and non-medical groups anonymously expressed great satisfaction, respectively, without statistically significant difference (χ2 = 0.565, p = 1.000). The average follow-up time was 4-36 months, and 87 trainees (96.67%) had mastered the operation of the MCCG in daily work.

CONCLUSIONS

Standardized training and assessment of magnetically controlled capsule endoscopists is effective and feasible. Additionally, a strict assessment system and long-term communication and learning can improve teaching effects.

The correlation between the main and minor lesions of synchronous multiple gastric neoplasms assessed gastroscopically and microscopically

BACKGROUND

Patients with early gastric cancer (EGC) are at high risk of developing synchronous multiple gastric neoplasms (SMGNs) after undergoing endoscopic submucosal dissection (ESD). However, most previous studies have had small sample sizes, and few have focused on association studies.

AIMS

This study aimed to analyze the associations between SMGN lesion data from patients with EGC treated with ESD and their correlation coefficients.

METHODS

The clinical ESD data from two hospitals from January 2008 to January 2021 were retrospectively analyzed. The main lesions were defined as those with a significant depth of infiltration. The larger tumor diameter was considered the main lesion if the lesions had the same infiltration depth.

RESULTS

Of the 1013 post-ESD cases examined, 95 cases (223 lesions) had SMGN, and 25 patients had more than three lesions. For the correlation analysis, 190 lesions were included. The study revealed a similarity in pathological type between main and minor lesions (rs = 0.37) and a positive correlation in infiltration depth (rs = 0.58). The mean diameter sizes of the main and minor lesions were 20.7 ± 8.3 mm and 13.1 ± 6.4 mm, respectively, with statistically significant differences (P < 0.001). A linear correlation was observed between the diameter size and a linear regression model was constructed, producing r = 0.38 [95% confidence interval (CI) 0.19-0.54], b = 0.29 (95% CI 0.14-0.44), t = 3.94, P < 0.001]. A correlation was identified between the vertical distribution of the main and minor lesions, the horizontal distribution, and the gross endoscopic morphology (ϕc = 0.25, P = 0.02; ϕc = 0.32, P < 0.001; ϕc = 0.60, P < 0.001).

CONCLUSIONS

The correlation coefficients for microscopic characteristics were higher than those for gastroscopy. There is a significant positive correlation between the main and minor lesions regarding pathological stage and depth of infiltration, respectively. The spatial distribution of the lesions and the gastroscopic morphology were similar.

Clinicopathological significance of intestinal metaplasia in endoscopically resected early gastric carcinoma

OBJECTIVE

To investigate the clinicopathological and prognostic significance of intestinal metaplasia (IM) in endoscopically resected early gastric carcinoma (EGC).

METHODS

Altogether 136 consecutive cases with EGC resected by endoscopic submucosal dissection over 5 years were included and divided into the early gastric cardiac (EGCC; n = 60) and non-cardiac carcinoma (EGNCC; n = 76) groups. Goblet cell IM and subtypes were determined with histology and immunostaining. Recurrence-free survival (RFS) was compared among various IM groups.

RESULTS

IM was identified in 128 (94.1%) EGC cases, including complete IM (n = 39), incomplete IM (n = 27), and mixed IM (n = 62). Incomplete IM was significantly more common in EGCC and exhibited a lower frequency of en bloc resection than the complete subtype. The frequency of synchronous or metachronous gastric tumor was significantly more common in EGCC with complete IM than in those with incomplete IM. Compared to EGC without IM, EGC with IM showed a significantly higher frequency of non-poorly cohesive carcinoma, en bloc resection, and non-eCuraC-1 grade. EGNCC with IM was significantly associated with negative resection margins and en bloc resection. The 5-year RFS was significantly lower in EGNCC patients with incomplete IM compared with those with mixed IM. The independent risk factors for RFS included tumor size >2 cm and eCuraC-1 grade.

CONCLUSIONS

Subtyping IM in EGC helped predict endoscopic resectability, prognosis, and risk of synchronous or metachronous gastric tumor. The significance of IM differed between EGCC and EGNCC. Large studies with longer follow-up are warranted to validate our findings.

Comparison of clinical outcomes and prognosis between surgery and endoscopic submucosal dissection in patients with synchronous multifocal early gastric cancer

BACKGROUND

Synchronous multiple early gastric cancer (SMEGC) refers to the simultaneous occurrence of two or more malignant cancer lesions in the stomach. For patients with multiple early gastric carcinomas, the choice of appropriate treatment remains controversial. This study is dedicated to comparing the clinical outcomes and prognosis of patients with SMEGC who underwent endoscopic submucosal dissection (ESD) or gastrectomy.

METHODS

A total of 180 patients with more than one malignant cancer lesion in the stomach who had received gastrectomy or ESD between 2012 and 2021 were retrospectively evaluated to determine their clinical outcomes and prognosis. Univariate and multivariate logistic regression were utilized to identify risk factors for tumor recurrence.

RESULTS

Over the 57.5 months median follow-up period for the 140 enrolled cases, tumor recurrence occurred in 8 (12%) in the ESD group but only 1 (1%) in the surgery group. Relapse-free survival (RFS) was higher in the surgery group (p = 0.023) in all cases; however, there was no significant difference in Overall survival (OS, p = 0.772). Complications were significantly higher in the surgery group than in the ESD group, but fewer in the radical distal gastrectomy group. Multivariate regression analysis revealed that ESD(p = 0.034), the main lesion size > 2 cm(p = 0.019), and undifferentiated tumor(p = 0.022) were independent risk factors for tumor recurrence.

CONCLUSIONS

For the treatment of simultaneous multifocal early gastric cancer, ESD has a good short-term effect and higher quality of life. However, ESD has a higher risk of recurrence than surgery. And we found that the partial gastrectomy appears to be considered as adequate treatment for some SMEGC patients.

An Image Turing Test on Realistic Gastroscopy Images Generated by Using the Progressive Growing of Generative Adversarial Networks

Generative adversarial networks (GAN) in medicine are valuable techniques for augmenting unbalanced rare data, anomaly detection, and avoiding patient privacy issues. However, there were limits to generating high-quality endoscopic images with various characteristics, such as peristalsis, viewpoints, light sources, and mucous patterns. This study used the progressive growing of GAN (PGGAN) within the normal distribution dataset to confirm the ability to generate high-quality gastrointestinal images and investigated what barriers PGGAN has to generate endoscopic images. We trained the PGGAN with 107,060 gastroscopy images from 4165 normal patients to generate highly realistic 5122 pixel-sized images. For the evaluation, visual Turing tests were conducted on 100 real and 100 synthetic images to distinguish the authenticity of images by 19 endoscopists. The endoscopists were divided into three groups based on their years of clinical experience for subgroup analysis. The overall accuracy, sensitivity, and specificity of the 19 endoscopist groups were 61.3%, 70.3%, and 52.4%, respectively. The mean accuracy of the three endoscopist groups was 62.4 [Group I], 59.8 [Group II], and 59.1% [Group III], which was not considered a significant difference. There were no statistically significant differences in the location of the stomach. However, the real images with the anatomical landmark pylorus had higher detection sensitivity. The images generated by PGGAN showed highly realistic depictions that were difficult to distinguish, regardless of their expertise as endoscopists. However, it was necessary to establish GANs that could better represent the rugal folds and mucous membrane texture.

Variation in the rate of detection of minute and small early gastric cancers at diagnostic endoscopy may reflect the performance of individual endoscopists

OBJECTIVE

The documented variation in gastric cancer (GC) detection among endoscopists has often been dismissed as a coincidental artefact of the low incidence of gastric neoplasms; it is not considered associated with differences in physicians' performance of the esophagogastroduodenoscopy procedure. This study is to confirm whether significant variations among endoscopists in early GC detection suggest the individual performance of the upper endoscopy.

DESIGN

A retrospective observational study at a single centre in Japan assessed the results of 218 early GCs detected during 25 688 routine esophagogastroduodenoscopies by 12 endoscopists. The main outcome was the rate of early GC detection for each endoscopist under the same circumstances. Other measures included the major diameters and locations of the lesions, Helicobacter pylori infection status, and baseline patient characteristics that could affect the prevalence of GC.

RESULTS

The early GC detection rates exhibited wide variation among endoscopists (0.09%-2.87%) despite performing routine esophagogastroduodenoscopies in a population with a similar background. Endoscopists were assigned to a low-detection group (n=6; detection rate: 0.47% (range: 0.09%-0.55%)) and a high-detection group (n=5; detection rate: 0.83% (range: 0.63%-1.12%)), with the single highest detector analysed separately due to his distinct detection rate (2.87%). Endoscopists in the high-detection group had better detection rates for minute (major diameter ≤5 mm) and small (major diameter 6-10 mm) GCs than the low-detection group (0.19%/0.23% vs 0.085%/0.098%). These differences were significant (p<0.01), although there were no significant differences in detection of larger tumours (major diameter ≥11 mm; 0.40% vs 0.28%; p=0.13). The tumour location and H. pylori status were similar in the low-detection group, high-detection group and for the highest detector.

CONCLUSION

Significant variation in the detection of hard-to-find, smaller GCs may reflect individual performance of the examination.

Quality indicators in the endoscopic detection of gastric cancer

Gastroscopy is the reference standard for the diagnosis of gastric cancer, but it is operator-dependent and associated with missed gastric cancer. The proliferation of gastroscopic examinations, increasingly for the screening and detection of subtle premalignant lesions, has motivated scrutiny of quality in gastroscopy. The concept of a high-quality endoscopic examination for the detection of superficial gastric neoplasia has been defined by expert guidelines to improve mucosal visualization, engender a systematic examination process and detect superficial neoplasia. This review discusses the evidence supporting the components of a high-quality diagnostic gastroscopic examination in relation to the detection of gastric cancer, and their potential role as procedural quality indicators to drive a structured improvement in clinically meaningful outcomes.

Endoscopic Screening for Missed Lesions of Synchronous Multiple Early Gastric Cancer during Endoscopic Submucosal Dissection

Aims

To evaluate the value of endoscopic screening during endoscopic submucosal dissection (ESD) in the detection of synchronous multiple early gastric cancer (SMEGC) and the risk factors for missed diagnosis of SMEGC.

Methods

We conducted gastric endoscopic screening during ESD operation in 271 patients with early gastric cancer (EGC) referred for ESD, and endoscopic follow-up within 1 year after the operation. The detection and characteristics of SMEGC were analyzed in three stages: before ESD, during ESD operation, and within 1 year after ESD.

Results

SMEGC was detected in 37 of 271 patients (13.6%). Among them, 21 patients with SMEGC (56.8%) were diagnosed before ESD, 9 (24.3%) were diagnosed with SMEGC by endoscopic screening during ESD operation, and 7 (18.9%) were found to have EGC lesions in the stomach during postoperative endoscopic follow-up within 1 year. The preoperative missed detection rate of SMEGC was 43.2%, and the rate of missed detection could be reduced by 24.3% (9/37) with endoscopic screening during ESD operation. Missed SMEGC lesions were more common in flat or depressed type and smaller in size than the lesions found before ESD. The presence of severe atrophic gastritis and age ≥60 years were significantly correlated with SMEGC (P < 0.05), while multivariate analysis showed that age ≥60 years was an independent risk factor (OR = 2.63, P < 0.05) for SMEGC.

Conclusions

SMEGC lesions are apt to be missed endoscopically. Special attention should be paid to small, depressed, or flat lesions in detecting SMEGC, especially in elderly patients or (and) patients with severe atrophic gastritis. Endoscopic screening during ESD operation can effectively reduce the missed diagnosis rate of SMEGC.

Long-term outcomes and clinical safety of expanded indication early gastric cancer treated with endoscopic submucosal dissection versus surgical resection: a meta-analysis

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) remains an investigational issue for early gastric cancer (EGC) with expanded indications owing to the risk of lymph node metastasis. In this study, we aimed to evaluate the clinical outcomes and safety of ESD versus surgical resection (SR) for EGC with expanded indications.

METHODS

The systematic review selected studies from PubMed, Embase, Cochrane and Web of Science databases from 2010 to 2020, and compared survival and clinical safety data of ESD with those of surgical resection for EGC with expanded indications. The fixed-effects or random-effects model was used to calculate the differences between the two groups. To assess the validity of the eligible studies, risk of bias was measured using the Newcastle-Ottawa Quality Assessment Scale.

RESULTS

Nine retrospective studies were used to calculate the differences in survival and clinical safety data between the two groups for EGC with expanded indications. Differences were not significant between the groups in terms of age, sex, tumour size, tumour histology or lesion morphology. Regarding tumour site, tumours located in the L area (the lower third of the stomach) were more likely to be found in the ESD group. With regard to metachronous and synchronous carcinomas, there was a significant difference favouring SR treatment (metachronous: OR=0.12, 95% CI=0.05 to 0.25, p<0.00001; synchronous: OR=0.11, 95% CI=0.02 to 0.46, p=0.003). Adverse event data were identified in six studies showing a significant difference favouring ESD treatment (ESD vs SR, OR=0.49, 95% CI=0.34 to 0.72. p=0.002). Additionally, six studies evaluating 5-year overall survival showed no significant differences between the two groups (HR=1.22, 95% CI=0.66 to 2.25, p=0.53). With regard to 5-year disease-free survival, patients with expanded indication EGC undergoing SR showed better survival (ESD vs SR, HR=3.29, 95% CI=1.60 to 6.76, p=0.001).

CONCLUSION

ESD provided favourable results for patients with EGC with expanded indications regarding clinical outcomes and safety in retrospective studies. Further, to detect synchronous or metachronous lesions, endoscopic surveillance should be performed following ESD. However, the included studies were observational, some did not have adequate adjustment for confounding factors and their results lacked generalisability due to their origin. Thus, further related randomised controlled trials are urgently encouraged.

PROSPERO REGISTRATION NUMBER

CRD42021251068.

A deep learning-based system for real-time image reporting during esophagogastroduodenoscopy: a multicenter study

BACKGROUND AND STUDY AIMS

Endoscopic reports are essential for the diagnosis and follow-up of gastrointestinal diseases. This study aimed to construct an intelligent system for automatic photo documentation during esophagogastroduodenoscopy (EGD) and test its utility in clinical practice.

PATIENTS AND METHODS

Seven convolutional neural networks trained and tested using 210,198 images were integrated to construct the endoscopic automatic image reporting system (EAIRS). We tested its performance through man-machine comparison at three levels: internal, external, and prospective test. Between May 2021 and June 2021, patients undergoing EGD at Renmin Hospital of Wuhan University were recruited. The primary outcomes were accuracy for capturing anatomical landmarks, completeness for capturing anatomical landmarks, and detected lesions.

RESULTS

The EAIRS outperformed endoscopists in retrospective internal and external test. A total of 161 consecutive patients were enrolled in the prospective test. The EAIRS achieved an accuracy of 95.2% in capturing anatomical landmarks in the prospective test. It also achieved higher completeness on capturing anatomical landmarks compared with endoscopists: (93.1% vs. 88.8%), and was comparable to endoscopists on capturing detected lesions: (99.0% vs. 98.0%).

CONCLUSIONS

The EAIRS can generate qualified image reports and could be a powerful tool for generating endoscopic reports in clinical practice.

High Expression of Claudin-4 Is Associated with Synchronous Tumors in Patients with Early Gastric Cancer

Claudin (CLDN) is a tight junction protein found in human epithelial cells and its altered expression is known to be associated with the progression of gastric cancer. We aimed to investigate the differential expression of CLDN-4 in early gastric cancer (EGC) according to its clinicopathological characteristics. We enrolled 53 patients with EGC who underwent surgical gastric resection from January 2007 to December 2018. The staining intensity of the tumor cells was scored as 0–3, and the percentage of staining was scored as 0–5; high expression was defined if the intensity plus percentage score was 7 or 8, and low expression was defined if the score was 0–6. Among the 53 patients, 16 (30.2%) showed low CLDN-4 expression, while 37 (69.8%) had high CLDN-4 expression. High CLDN-4 expression was significantly associated with intestinal-type EGC (low: 12.5% vs. high: 56.8%, p = 0.003), open-type atrophic change (low: 60.0% vs. high: 90.9%, p = 0.011), and the presence of synchronous tumors (0 vs. 32.4%, p = 0.010), and all 12 EGCs with synchronous tumors showed high CLDN-4 expression. However, expression of CLDN-3, a typical intestinal phenotype CLDN, was neither correlated with CLDN-4 expression nor associated with synchronous tumors. Taken together, high CLDN-4 expression may be considered as an auxiliary tool for screening synchronous tumors in patients with EGC.

Second gastric cancer after curative endoscopic resection of differentiated-type early gastric cancer: post-hoc analysis of a single-arm confirmatory trial

BACKGROUND AND AIMS

Endoscopic resection (ER) for early gastric cancer (EGC) can preserve the stomach; however, the remaining stomach can develop second gastric cancer. Few reports have prospectively investigated the incidence and treatment outcomes of second gastric cancer.

METHODS

This post-hoc analysis used the dataset of the single-arm confirmatory trial, JCOG0607. The key inclusion criteria for JCOG0607 were solitary differentiated-type EGC and no previous gastrectomy or endoscopic treatment for EGC. Three hundred seventeen patients who underwent curative ER were included in this study. Surveillance endoscopy was performed 1 to 3 months after the initial ER and subsequently annually for at least 5 years. A lesion detected ≤1 year and >1 year after the initial ER was defined as overlooked gastric cancer (OGC) and metachronous gastric cancer (MGC), respectively.

RESULTS

During a median follow-up period of 6.0 years (interquartile range, 5.1-7.0), 30 OGCs and 61 MGCs were detected in 24 and 48 patients, respectively. The cumulative incidence of OGC at 1 year and MGC at 5 years was 7.6% and 12.7%, respectively. ER and gastrectomy were performed in 85 lesions and 6 lesions, respectively. Pathologic evaluation showed 78 mucosal cancers, 12 submucosal cancers, and 1 advanced cancer. Eventually, 28 OGCs and 52 MGCs fulfilled the pathologic criteria for curative ER.

CONCLUSIONS

Our study was the first to reveal the actual incidence of second gastric cancer after curative ER for differentiated-type gastric cancer. Most lesions could be treated with ER. Continuous endoscopic surveillance after curative ER is important to detect second gastric cancer.

A predictive risk-scoring model for multiple synchronous early gastric cancers or gastric dysplasia before initial endoscopic resection

OBJECTIVE

To establish a new and easy-to-use risk-scoring predictive model to help identify high-risk patients with multiple synchronous gastric neoplasms (MSGN), including early gastric cancer (EGC) and gastric dysplasia (GD), before initial endoscopic resection (ER).

METHODS

We retrospectively enrolled 1361 patients with EGC or GD who had undergone ER from November 2006 to September 2019. The patients were randomly divided into the training (n = 681) and validation cohorts (n = 680). In the training phase a prediction score was constructed to assess the independent predictors of MSGN based on multivariate logistic regression analysis. The performance of the prediction model was evaluated using the receiver operating characteristic (ROC) curve and the Hosmer-Lemeshow test.

RESULTS

Of the 1361 patients, 122 (9.0%) had MSGN. Three predictors for MSGN were scored and weighted, as follows: elderly male (≥65 y; three points), a family history of gastric cancer (two points) and surface redness (two points). Accordingly, patients were divided into the low (risk score, 0-3 points) or high-risk groups (risk score, 4-7 points). In the validation cohort, the incidence of MSGN in the low-risk and high-risk groups were 6.1% and 32.0%, respectively (P < 0.001). Our predictive risk-scoring model showed good discrimination (the area under the ROC curve [AUROC] 0.719, 95% confidence interval [CI] 0.634-0.794, P < 0.001) and calibration ability (Hosmer-Lemeshow test, χ²  = 6.539, P = 0.587) in the validation group.

CONCLUSION

This risk-scoring model has a good performance in predicting MSGN before the initial ER.

Linked Color Imaging Can Improve Detection Rate of Early Gastric Cancer in a High-Risk Population: A Multi-Center Randomized Controlled Clinical Trial

BACKGROUND

Early diagnosis of gastric cancer is difficult in China due to the lack of a valid method for endoscopic screening. Early gastric cancer, especially flat gastric cancer, lacks specific endoscopic features. Many cases appear to be similar to ordinary gastritis cases under normal white light endoscopy, which can lead to misdiagnosis.

AIMS

In order to find a new method to improve detection rate of early gastric cancer in China, we designed a trial to validate linked color imaging (LCI) for screening of early gastric cancer in a high-risk population, as compared to white light imaging (WLI).

METHOD

Subjects were randomly allocated to either the LCI + WLI or WLI group and then subjected to gastroscopy and all endoscopies were made after special preparation. All endoscopists had knowledge of this experiment. The main indicator was the rate of detection of gastric neoplastic lesions. The difference in the detection rate between the two groups is reported.

RESULTS

The detection rate was 4.31% in the WLI group and 8.01% in the LCI + WLI group. This is a difference of 3.70% with a P value < 0.001 and an OR (95% CI) of 1.934 (1.362, 2.746). The lower limit of the 95% CI was greater than 0, and the superiority margin was 1%.

CONCLUSION

The detection rate of gastric neoplastic lesions was higher in the LCI + WLI group than in the WLI group, LCI might be an effective method for screening early gastric cancer.

Artificial intelligence in gastric cancer: a translational narrative review

Increasing clinical contributions and novel techniques have been made by artificial intelligence (AI) during the last decade. The role of AI is increasingly recognized in cancer research and clinical application. Cancers like gastric cancer, or stomach cancer, are ideal testing grounds to see if early undertakings of applying AI to medicine can yield valuable results. There are numerous concepts derived from AI, including machine learning (ML) and deep learning (DL). ML is defined as the ability to learn data features without being explicitly programmed. It arises at the intersection of data science and computer science and aims at the efficiency of computing algorithms. In cancer research, ML has been increasingly used in predictive prognostic models. DL is defined as a subset of ML targeting multilayer computation processes. DL is less dependent on the understanding of data features than ML. Therefore, the algorithms of DL are much more difficult to interpret than ML, even potentially impossible. This review discussed the role of AI in the diagnostic, therapeutic and prognostic advances of gastric cancer. Models like convolutional neural networks (CNNs) or artificial neural networks (ANNs) achieved significant praise in their application. There is much more to be fully covered across the clinical administration of gastric cancer. Despite growing efforts, adapting AI to improving diagnoses for gastric cancer is a worthwhile venture. The information yield can revolutionize how we approach gastric cancer problems. Though integration might be slow and labored, it can be given the ability to enhance diagnosing through visual modalities and augment treatment strategies. It can grow to become an invaluable tool for physicians. AI not only benefits diagnostic and therapeutic outcomes, but also reshapes perspectives over future medical trajectory.

Development and Validation of an Automatic Image-Recognition Endoscopic Report Generation System: A Multicenter Study

INTRODUCTION:

Conventional gastrointestinal (GI) endoscopy reports written by physicians are time consuming and might have obvious heterogeneity or omissions, impairing the efficiency and multicenter consultation potential. We aimed to develop and validate an image recognition–based structured report generation system (ISRGS) through a multicenter database and to assess its diagnostic performance.

Methods:

First, we developed and evaluated an ISRGS combining real-time video capture, site identification, lesion detection, subcharacteristics analysis, and structured report generation. White light and chromoendoscopy images from patients with GI lesions were eligible for study inclusion. A total of 46,987 images from 9 tertiary hospitals were used to train, validate, and multicenter test (6:2:2). Moreover, 5,699 images were prospectively enrolled from Qilu Hospital of Shandong University to further assess the system in a prospective test set. The primary outcome was the diagnosis performance of GI lesions in multicenter and prospective tests.

Results:

The overall accuracy in identifying early esophageal cancer, early gastric cancer, early colorectal cancer, esophageal varices, reflux esophagitis, Barrett’s esophagus, chronic atrophic gastritis, gastric ulcer, colorectal polyp, and ulcerative colitis was 0.8841 (95% confidence interval, 0.8775–0.8904) and 0.8965 (0.8883–0.9041) in multicenter and prospective tests, respectively. The accuracy of cecum and upper GI site identification were 0.9978 (0.9969–0.9984) and 0.8513 (0.8399–0.8620), respectively. The accuracy of staining discrimination was 0.9489 (0.9396–0.9568). The relative error of size measurement was 4.04% (range 0.75%–7.39%).

DISCUSSION:

ISRGS is a reliable computer-aided endoscopic report generation system that might assist endoscopists working at various hospital levels to generate standardized and accurate endoscopy reports (http://links.lww.com/CTG/A485).

Common Locations of Gastric Cancer: Review of Research from the Endoscopic Submucosal Dissection Era

Detection of early-stage gastric cancer improves the prognosis of patients. Endoscopic submucosal dissection (ESD) is a curative and stomach-preserving treatment for early gastric cancer (EGC) associated with a low risk of lymph node metastasis. However, several studies have reported missed diagnosis of gastric cancer. Therefore, endoscopists are required to learn accurate diagnostic skills to eliminate endoscopic blind spots. A systematic screening protocol to map the entire stomach without blind spots reduces the risk of missed lesions. Knowledge of the features of EGC or dysplasia is essential to identify suspicious lesion. Information of the common sites of occurrence of EGC can also enable a detailed endoscopic examination to improve detection rates. Previous reports investigating the location of gastric cancers resected by ESD or surgery showed that the antrum and lesser curvature of stomach were predominantly affected. Helicobacter pylori-induced atrophic changes advance from the antrum to the corpus along the lesser curvature, predominantly affecting these areas. Gastric cancers in the antrum and the lower corpus are also commonly missed during screening examination. Therefore, a careful examination of the lower third stomach is warranted to avoid missing synchronous and metachronous gastric lesions. Knowledge of the location of EGC enables accurate endoscopic examination and detection of EGC in early stage.

Early detection of gastric cancer using global, genome-wide and IRF4, ELMO1, CLIP4 and MSC DNA methylation in endoscopic biopsies

Clinically useful molecular tools to triage gastric cancer patients are not currently available. We aimed to develop a molecular tool to predict gastric cancer risk in endoscopy-driven biopsies obtained from high-risk gastric cancer clinics in low resource settings.

We discovered and validated a DNA methylation biomarker panel in endoscopic samples obtained from 362 patients seen between 2004 and 2009 in three high-risk gastric cancer clinics in Lima, Perú, and validated it in 306 samples from the Cancer Genome Atlas project (“TCGA”). Global, epigenome wide and gene-specific DNA methylation analyses were used in a Phase I Biomarker Development Trial to identify a continuous biomarker panel that combines a Global DNA Methylation Index (GDMI) and promoter DNA methylation levels of IRF4, ELMO1, CLIP4 and MSC.

We observed an inverse association between the GDMI and histological progression to gastric cancer, when comparing gastritis patients without metaplasia (mean = 5.74, 95% CI, 4.97−6.50), gastritis patients with metaplasia (mean = 4.81, 95% CI, 3.77−5.84), and gastric cancer cases (mean = 3.38, 95% CI, 2.82−3.94), respectively (p < 0.0001). Promoter methylation of IRF4 (p < 0.0001), ELMO1 (p < 0.0001), CLIP4 (p < 0.0001), and MSC (p < 0.0001), is also associated with increasing severity from gastritis with no metaplasia to gastritis with metaplasia and gastric cancer.

Our findings suggest that IRF4, ELMO1, CLIP4 and MSC promoter methylation coupled with a GDMI>4 are useful molecular tools for gastric cancer risk stratification in endoscopic biopsies.

Characteristics of Synchronous and Metachronous Multiple Gastric Tumors after Endoscopic Submucosal Dissection of Early Gastric Neoplasm

Background/Aims

Endoscopic submucosal dissection (ESD) has been widely accepted as a method of treatment of early gastric tumor. This study aimed to identify the incidence and characteristics of multiple gastric tumors after ESD.

Methods

Patients with early gastric tumors who were treated by ESD from January 2004 to June 2012 and followed up with endoscopic examination periodically for at least 1 year were enrolled. All multiple gastric lesions were subsequently treated with ESD and the medical records of the patients were retrospectively reviewed.

Results

In total, 643 patients were included. The mean duration of endoscopic follow-up was 45.27±27.59 (range, 12–148) months. Overall, 144 patients (22.4%) showed multiple gastric tumors during the follow-up period (44 synchronous [6.8%] and 100 metachronous [15.5%]). The cumulative incidence rate steadily increased during the follow-up period. More than 50% of the tumors that developed at the same longitudinal location of the stomach were of the same macroscopic and histological type as the primary lesions.

Conclusions

Because synchronous and/or metachronous gastric tumors are common, considerable attention should be paid to detect multiple gastric lesions after ESD of early gastric neoplasm.

Early-Stage Gastric Cancer Can Be Found in Improved Atrophic Mucosa over Time from Successful Helicobacter pylori Eradication

BACKGROUND/AIMS

Early-stage gastric cancer (EGC) is detected even after successful Helicobacter pylori eradication. This study is aimed at clarifying the clinicopathological characteristics of EGC detected after successful H. pylori eradication.

METHODS

This retrospective study analyzed 57 cases of EGC detected after successful H. pylori eradication and resected endoscopically at Kyoto Prefectural University of Medicine, between January 2009 and June 2014. Clinicopathological findings of 57 cases (H. pylori-eradicated group) were investigated, and compared with those in active H. pylori infection resected in the same period (H. pylori-positive group).

RESULTS

Most EGCs were detected in patients with severe atrophic mucosa, both in H. pylori-eradicated and H. pylori-positive groups, while the percentage of EGC detected in patients with mild atrophic mucosa gradually increased over time from successful eradication (H. pylori-positive: 7%, up to the fourth year since eradication: 11%, after the fifth year since eradication: 32%). The percentage of EGC detected in patients with mild atrophic mucosa after the fifth year since eradication was significantly higher than that in patients with active H. pylori infection (p = 0.004).

CONCLUSION

After the fifth year following eradication, we should be alert to the incidence of EGC, irrespective of the severity of mucosal atrophic change.

Linked color imaging (LCI), a novel image-enhanced endoscopy technology, emphasizes the color of early gastric cancer

BACKGROUND AND STUDY AIMS

 Linked color imaging (LCI) and blue laser imaging (BLI) are novel image-enhanced endoscopy technologies with strong, unique color enhancement. We investigated the efficacy of LCI and BLI-bright compared to conventional white light imaging (WLI) by measuring the color difference between early gastric cancer lesions and the surrounding mucosa.

PATIENTS AND METHODS

 Images of early gastric cancer scheduled for endoscopic submucosal dissection were captured by LCI, BLI-bright, and WLI under the same conditions. Color values of the lesion and surrounding mucosa were defined as the average of the color value in each region of interest. Color differences between the lesion and surrounding mucosa (ΔE) were examined in each mode. The color value was assessed using the CIE L*a*b* color space (CIE: Commission Internationale d'Eclairage).

RESULTS

 We collected images of 43 lesions from 42 patients. Average ΔE values with LCI, BLI-bright, and WLI were 11.02, 5.04, and 5.99, respectively. The ΔE was significantly higher with LCI than with WLI ( P  < 0.001). Limited to cases of small ΔE with WLI, the ΔE was approximately 3 times higher with LCI than with WLI (7.18 vs. 2.25). The ΔE with LCI was larger when the surrounding mucosa had severe intestinal metaplasia ( P  = 0.04). The average color value of a lesion and the surrounding mucosa differed. This value did not have a sufficient cut-off point between the lesion and surrounding mucosa to distinguish them, even with LCI.

CONCLUSION

 LCI had a larger ΔE than WLI. It may allow easy recognition and early detection of gastric cancer, even for inexperienced endoscopists.

Missing rate for gastric cancer during upper gastrointestinal endoscopy: a systematic review and meta-analysis

OBJECTIVES

Esophagogastroduodenoscopy (EGD) is considered a very effective method to identify gastric cancer (GC). However, the existence of missed lesions has been frequently discussed. This systematic review and meta-analysis aimed at assessing the magnitude of missing GC diagnosis with EGD and its predictive factors.

METHODS

MEDLINE was searched to identify all studies assessing and reporting the proportion of missed GC diagnosis with EGD. Pooled proportion and negative predictive values were computed using the random-effects model and heterogeneity was assessed using the Cochrane Q-test and I.

RESULTS

The studies included (n=22) were grouped by study design. The pooled negative predictive value was 99.7% (95% confidence interval 99.6-99.9%). Missed GCs proportion was 9.4% (95% confidence interval 5.7-13.1%), being 10.0% in studies including patients with negative EGD followed over time, 8.3% in studies including patients with GC, and 23.3% in studies evaluating the proportion of missed synchronous lesions. Mainly, missed cancers were located in the gastric body both in Eastern and in Western studies (39 and 47%, respectively). The majority of missed GCs were adenocarcinomas. Younger age (<55 years), female sex, marked gastric atrophy, gastric adenoma or ulcer, and inadequate number of biopsy fragments were reported as predictive factors for diagnostic failure.

CONCLUSION

EGD is a very effective method to rule out GC. However, missing GC with EGD is not uncommon, with one out of 10 cancers being potentially missed. Interestingly, lesions were more often missed in the body and therefore a more rigorous protocol for endoscopy and biopsy should be implemented worldwide.

Characteristics of Missed Simultaneous Gastric Lesions Based on Double-Check Analysis of the Endoscopic Image

BACKGROUND/AIMS

The detection of multifocal lesions is important for the successful management of gastric neoplasms. We investigated the characteristics of missed simultaneous lesions and the reason for the missed diagnoses.

METHODS

A total of 140 patients who underwent repeat endoscopy before endoscopic resection between June 2013 and June 2014 were retrospectively reviewed. We classified simultaneous lesions into three groups based on a review of earlier images: group 1, no images of the location of simultaneous lesions were taken; group 2, no corresponding lesion was evident in the previous images; and group 3, simultaneous lesions were visible in the earlier images but a biopsy was not performed.

RESULTS

Simultaneous lesions were found in 12 patients (8.6%) with 13 lesions, comprising 10 dysplasia (76.9%) and three adenocarcinoma (23.1%). Regarding the reasons for missed diagnoses, seven lesions (53.8%) were classified as group 3, five (38.5%) as group 1, and the remaining lesion (7.7%) as group 2. There were no significant differences in the characteristics of the patients with and without simultaneous lesions.

CONCLUSIONS

Lesions disregarded or unnoticed during endoscopic examination were the main reason for missed diagnosis of simultaneous lesions. Endoscopists should consider the possibility of simultaneous lesions and attempt to meticulously evaluate the entire gastric mucosa.

Detection and Management of Early Gastric Cancer

OPINION STATEMENT

Early gastric cancer (EGC), defined as being confined to the submucosa, is a curable condition. In recent years, endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have been widely applied to subgroups of mucosal cancers, thereby avoiding the burden of operation while preserving gastric function. However, it can be difficult to identify mucosal cancers, which often evade detection due to their flat shapes without ulceration. Proper preparation to clean the mucosal surface, detailed systematic observation of the entire stomach, and the use of high-resolution systems for both endoscopies equipped with image-enhanced modality and monitors would facilitate the detection of such lesions. It is also critical to evaluate the resected specimen to confirm completeness of resection (tumor-free lateral and vertical margins as well as the absence of lymphatic and vascular invasion). If the resection is incomplete, further treatment is usually recommended-further endoscopic resection for patients with positive lateral margins or surgery for patients with positive vertical margins or with lymphatic or vascular involvement. The five-year survival for endoscopically resected EGC is excellent-and comparable to that of surgical therapy. Since most gastric cancers are caused by Helicobacter pylori, this infection should be tested for routinely. If a patient is H. pylori-positive, eradication is recommended, as heterotopic, metachronous recurrence of EGC is subsequently reduced. Importantly, basic principles for early diagnosis and endoscopic treatment of EGC can be applied to neoplasms arising in other parts of the gut, such as the esophagus and colon, and would be beneficial for patients through preserving organ function and minimizing operative intervention.

Improving the Endoscopic Detection Rate in Patients with Early Gastric Cancer

Endoscopists should ideally possess both sufficient knowledge of the endoscopic gastrointestinal disease findings and an appropriate attitude. Before performing endoscopy, the endoscopist must identify several risk factors of gastric cancer, including the patient's age, comorbidities, and drug history, a family history of gastric cancer, previous endoscopic findings of atrophic gastritis or intestinal metaplasia, and a history of previous endoscopic treatments. During endoscopic examination, the macroscopic appearance is very important for the diagnosis of early gastric cancer; therefore, the endoscopist should have a consistent and organized endoscope processing technique and the ability to comprehensively investigate the entire stomach, even blind spots.

Preliminary study of photodynamic diagnosis using 5-aminolevulinic acid in gastric and colorectal tumors

AIM: To investigate the utility of photodynamic diagnosis (PDD) using 5-aminolevulinic acid (5-ALA) to detect gastric/colorectal tumors.

METHODS: This prospective single-center study investigated inter-subject variability in patients with early-stage gastric/colorectal tumor indicated for endoscopic resection. Subjects were patients with gastric or colorectal tumors who had undergone endoscopic resection between November 2012 and November 2013. Selection criteria included age 20-80 years, either sex, and provision of informed consent. Patients were orally administered 20 mg/kg of 5-ALA enteric-coated capsules (SBI ALApromo Co., Tokyo, Japan). Administration of 5-ALA was followed by endoscopic resection of gastric or colorectal tumors, and the resected specimens were examined using a video autofluorescence processor and a fluorescence endoscope (SAFE-3000 and EB-1970AK, respectively; Pentax, Tokyo, Japan). The primary endpoint was the presence of fluorescence in tumors. Endoscopic, macroscopic, and histopathologic findings of tumors were assessed. We also evaluated adverse events of the present procedure as a secondary endpoint and examined each patient for the presence of known adverse effects of 5-ALA, namely, hematocytopenia, liver dysfunction, hypotension, nausea, and photosensitivity.

RESULTS: We enrolled 10 patients (7 men, 3 women) (n = 13 lesions: 10 gastric/3 colorectal tumors). Fluorescence was detected in 7/13 (53.8%) lesions. No significant differences in sex (male: 55.6% vs female: 50.5%, P = 1.00), age (67.1 ± 1.9 years vs 65.0 ± 2.0 years, P = 0.45), tumor color (reddish: 60.0% vs discolored: 33.3%, P = 0.56), tumor diameter (15.0 ± 2.1 mm vs 14.2 ± 2.3 mm, P = 0.80), macroscopic type (protruded: 70.0% vs depressed 0%, P = 0.07), histologic type (differentiated type: 58.3% vs 0%, P = 0.46), invasion depth (mucosal layer: 55.6% vs submucosal layer: 33.3%, P = 1.00), lymphatic invasion (present: 33.3% vs absent: 50.0%, P = 1.00), venous invasion (present: 0% vs absent: 54.5%, P = 1.00) or procedure time of endoscopic resection (36.3 ± 8.3 min vs 36.7 ± 9.0 min, P = 0.98) were observed between the patients with and without fluorescence. Fluorescence detection rate tended to be high for elevated lesions. Liver dysfunction developed in 4/10 (40.0%) patients. The extent of the liver dysfunction was a slight increase in transaminases and total bilirubin levels, which spontaneously improved in the patients. None of the patients developed photosensitivity.

CONCLUSION: Results of this preliminary study suggest the utility of PDD using 5-ALA for screening of gastric and colorectal cancers.

Endoscopic gastric cancer screening and surveillance in high-risk groups

Gastric cancer remains a major cancer problem world-wide and future incidence will likely increase due to rapidly aging population demographics. Population-based screening is being undertaken in Korea and Japan, where gastric cancer incidence rates are high, and seems to be effective in reducing mortality from gastric cancer. However, such strategies are difficult to implement in countries with a low incidence or limited resources. Thus, screening strategies should be directed towards high-risk population subgroups. Gastric cancer has a relatively long mean sojourn time, and prognosis of early-stage disease is excellent. In general population, screening at 2-year interval in Korea seems to be effective for early-stage diagnosis. In subjects with atrophic gastritis or intestinal metaplasia, surveillance is recommended at 1 to 3 years intervals according to European and Japanese recommendation. Screening intervals for family members with sporadic gastric cancer has not yet been adequately evaluated, but 1-year interval is recommended for hereditary diffuse gastric cancer family-members. Gastric cancer patients treated by endoscopic resection are the highest-risk group, and 1-year interval surveillance can detect most metachronous gastric cancers at an early stage. Future gastric cancer surveillance strategies using endoscopy should be guided by risk-stratification assessment, and further refinement of optimal surveillance intervals is needed.

Endoscopic surveillance strategy after endoscopic resection for early gastric cancer

Early detection of early gastric cancer (EGC) is important to improve the prognosis of patients with gastric cancer. Recent advances in endoscopic modalities and treatment devices, such as image-enhanced endoscopy and high-frequency generators, may make endoscopic treatment, such as endoscopic submucosal dissection, a therapeutic option for gastric intraepithelial neoplasia. Consequently, short-term outcomes of endoscopic resection (ER) for EGC have improved. Therefore, surveillance with endoscopy after ER for EGC is becoming more important, but how to perform endoscopic surveillance after ER has not been established, even though the follow-up strategy for more advanced gastric cancer has been outlined. Therefore, a surveillance strategy for patients with EGC after ER is needed.

Incidence of metachronous gastric cancer in the remnant stomach after synchronous multiple cancer surgery

BACKGROUND

In the preoperative evaluation for gastric cancer, high-resolution endoscopic technologies allow us to detect small accessory lesions. However, it is not known if the gastric remnant after partial gastrectomy for synchronous multiple gastric cancers has a greater risk for metachronous cancer. The purpose of this study was to determine the incidence of metachronous cancer in this patient subset compared with that after solitary cancer surgery.

METHODS

Data on a consecutive series of 1,281 patients gastrectomized for early gastric cancer from 1991 to 2007 were analyzed retrospectively. The 715 gastric remnants after distal gastrectomy were periodically surveyed by endoscopic examination in Shikoku Cancer Center. Among those surveyed cases, 642 patients were pathologically diagnosed with solitary lesion (SO group) and 73 patients with synchronous multiple lesions (MU group) at the time of the initial surgery.

RESULTS

In the follow-up period, 15 patients in the SO group and 3 patients in the MU group were diagnosed as having metachronous cancer in the gastric remnant. The cumulative 4-year incidence rate was 1.9 % in the SO group and 5.5 % in the MU group. The difference did not reach the significant level by the log-rank test.

CONCLUSIONS

The incidence of metachronous cancer is higher after multiple cancer surgery; however, the difference is not statistically significant.

Seven synchronous early gastric cancer with 28 lymph nodes metastasis

An 85 year male patient complaining epigastric discomfort was admitted. From the esophagogastroduodenoscopy, three early gastric cancer (EGCa) lesions had been identified and these were diagnosed as adenocarcinoma with poorly differentiated cell type. The patient underwent operation. From the post-operative mapping, however, additional 4 EGCa lesions were found, and the patient was diagnosed with 7 synchronous EGCa. Out of the 7 EGCa lesions, 6 had shown invasion only to the mucosal layer and one had shown invasion into the 1/3 layer of submucosa. In spite of such superficial invasions, 28 of 48 lymph nodes had been identified as metastases. The multiple lesions of EGCa do not increase the risk of lymph node metastasis, but if their differentiations are poor or if they have lympho-vascular invasion, multiple lymph node metastases could incur even if the depth of invasion is limited to the mucosal layer or the upper portion of the submucosal layer.

Causes of missed synchronous gastric epithelial neoplasms with endoscopic submucosal dissection: a multicenter study

OBJECTIVE

Unlike surgery, endoscopic submucosal dissection (ESD) removes gastric epithelial neoplasms within a tight margin, leaving most normal tissue around the neoplasm intact, thus resulting in a high risk for missed synchronous gastric epithelial neoplasms (mSGENs). The purpose of this study was to evaluate the characteristics and risk factors of mSGENs (mSGENs) compared to simultaneously identified SGENs (siSGENs) in patients who underwent ESD.

MATERIALS AND METHODS

The authors have retrospectively examined 312 SGENs from 275 patients treated with ESD at three hospitals in Korea between January 2004 and May 2011. The incidence and clinicopathological features of SGENs, mSGENs, and siSGENs were investigated. Any second epithelial neoplasm found within 1 year of the first ESD procedure was defined as an mSGEN and any neoplasm detected simultaneously with the first neoplasm was defined as a siSGEN.

RESULTS

The overall incidence of ESD patients with SGENs was 9.1% (275 of 3018 patients). Of the SGENs, 45.2% were siSGENs and 54.8% were mSGENs. Independent risk factors for mSGENs were adenoma as the first gastric lesion (Exp (B) = 2.154, 95% CI: 1.282-3.262) and duration of endoscopic examination before the first ESD (Exp (B) = 1.074, 95% CI: 1.001-1.141). The results suggest that 33% of mSGENs could have been identified during the endoscopic examination prior to ESD.

CONCLUSION

Additional effort needs to be expended in identifying siSGENs, particularly prior to ESD for less serious adenomas. This should include sufficient time for endoscopic examination, prior to ESD, to ensure a thorough examination for siSGENs.

Scheduled endoscopic surveillance controls secondary cancer after curative endoscopic resection for early gastric cancer: a multicentre retrospective cohort study by Osaka University ESD study group

BACKGROUND

After endoscopic submucosal dissection (ESD) of early gastric cancer (EGC), patients are at high risk for synchronous or metachronous multiple gastric cancers.

OBJECTIVE

To elucidate the time at which multiple cancers develop and to determine whether scheduled endoscopic surveillance might control their development.

DESIGN

A multicentre retrospective cohort study from 12 hospitals was conducted. Patients with EGC who underwent ESD with en bloc margin-negative curative resection were included. Synchronous cancer was classified as concomitant cancer or missed cancer. The cumulative incidence of metachronous cancers and overall survival rate were calculated using the Kaplan-Meier method.

RESULTS

From April 1999 to December 2010, 1258 patients met the inclusion criteria. Synchronous or metachronous multiple cancers were detected in 175 patients (13.9%) during a mean of 26.8 months. Among the 110 synchronous cancers, 21 were missed at the time of the initial ESD. Many of the missed lesions existed in the upper third of the stomach and the miss rate was associated with the endoscopist's inexperience (<500 oesophagogastroduodenoscopy cases). The cumulative incidence of metachronous cancers increased linearly and the mean annual incidence rate was 3.5%. The incidence rate did not differ between patients with or without Helicobacter pylori eradication. Four lesions (0.32%) were detected as massively invading cancers during the follow-up.

CONCLUSIONS

Nineteen per cent of synchronous cancers were not detected until the initial ESD. The incidence rate of metachronous cancer after ESD was constant. Scheduled endoscopic surveillance showed that almost all recurrent lesions were treatable by endoscopic resection.

Simultaneous endoscopic submucosal dissection for synchronous double early gastric cancer

BACKGROUND

This study aims to evaluate the safety and efficacy of simultaneous endoscopic submucosal dissection (ESD) for synchronous double early gastric cancers.

METHODS

We retrospectively evaluated 832 single gastric cancers from 789 patients treated by single ESD (single group) and 124 synchronous double cancers from 62 patients treated by simultaneous ESD (simultaneous group).

RESULTS

The overall rate of en bloc resection and curative resection was comparable between the two groups. Procedure time was significantly longer in the simultaneous group than in the single group (131.0 ± 66.5 and 94.8 ± 64.1 min, respectively, P < 0.001). White blood cell count on the day after ESD was significantly higher in the simultaneous group (9310 ± 2774/μl) than in the single group (8633 ± 2341/μl) (P = 0.032). Length of fasting period after ESD was 1.1 ± 0.5 days in the single group and 1.4 ± 1.1 days in the simultaneous group (P = 0.082). Complications were more frequent in the simultaneous group than in the single group (11.3 vs. 5.4 %, respectively), but the difference was not significant (P = 0.082). Complication rate per one lesion did not differ between the two groups (5.6 vs. 5.4 %, respectively, P = 0.914). Multivariate analysis showed procedure time longer than 150 min was independently predictive for complications of simultaneous ESD (P < 0.042, odds ratio = 6.094). Large tumors, upper portion location and tumors not in the standard guideline criteria were significantly associated with long procedure time.

CONCLUSIONS

Simultaneous ESD for synchronous early gastric cancer can be a feasible and safe option, and it can reduce hospital stay. These results need to be validated by further studies.

Multiple synchronous early gastric cancers: high-risk group and proper management

BACKGROUND

Multiple early gastric cancers (MEGCs) may be easily missed on preoperative gastroscopy because the lesions are predominantly small and flat. This may increase the risks of gastric remnant lesions and recurrence. We aimed to define high-risk group of MEGC and suggest proper management of missed lesion after partial gastrectomy.

METHODS

A total of 117 patients with MEGCs and 2182 with solitary EGC who underwent gastrectomy between 2008 and 2010 were retrospectively analyzed to determine their clinicopathologic characteristics. We also assessed their family history, the presence of Helicobacter pylori infection, and of precancerous lesions; and the results of microsatellite instability and immunohistochemical staining of the primary (largest) lesion for p53, human epidermal growth factor receptor [HER1], and HER2 were also reviewed.

RESULTS

MEGCs occurred more frequently in elderly males and in patients with adenoma, atrophic gastritis, or a family history of gastric cancer. These patients had more favorable pathologic findings, including less deep invasion, better differentiation, more intestinal type, and less frequent lymphovascular/perineural invasion than patients with solitary EGCs. The mean size of MEGCs was smaller (2.44 cm vs 3.36 cm) but there was no difference in the number of metastatic lymph nodes. Most accessory lesions were confined to the mucosal layer, with their average diameter was 1.82 cm.

CONCLUSIONS

A careful preoperative gastroscopy should be performed in patients at high risk of MEGCs and more cautious postoperative endoscopic surveillance of the remnant stomach is required. For missed foci on remnant stomach, endoscopic resection can be a good option if it meets the criteria.

Lymph node metastasis in multiple synchronous early gastric cancer

BACKGROUND

Although endoscopic resection for early gastric cancer (EGC) is increasingly available, it has not been determined whether indications for endoscopic resection are equally acceptable for multiple EGCs.

OBJECTIVE

To compare the various clinicopathologic factors and risk of lymph node (LN) metastasis between multiple and solitary EGCs.

DESIGN

Case-control study.

SETTING

University hospital.

PATIENTS

This study involved 1717 patients with 156 multiple and 1561 solitary EGCs.

INTERVENTION

Gastrectomy with LN dissection.

MAIN OUTCOME MEASUREMENTS

Incidence of LN metastasis.

RESULTS

In multiple EGCs, main lesions had larger tumor size and deeper invasion depth than the accessory lesions (P < .001). The clinicopathologic features of multiple EGCs were similar to those of solitary EGCs with respect to tumor size, depth of invasion, lymphovascular invasion, and incidence of LN metastasis. Importantly, the risk of LN metastasis in multiple EGCs that met the indication criteria for endoscopic resection was not significantly different from that in solitary EGCs. Tumors meeting conventional indications for endoscopic resection had no risk of LN metastasis, whereas tumors meeting expanded indications showed a similar risk of LN metastasis in the two groups. In multiple EGCs, tumor size ≥3 cm and lymphovascular invasion were independent risk factors of LN metastasis.

LIMITATIONS

Small number of patients with multiple EGCs studied.

CONCLUSION

Multiple EGCs had clinicopathologic characteristics and risk of LN metastasis similar to those of solitary EGCs. Endoscopic resection may be adopted as curative treatment for multiple EGCs that meet indications for endoscopic resection. Further studies are needed to verify the present study results.

X-ray diagnosis of synchronous multiple primary carcinoma in the upper gastrointestinal tract

AIM: To analyze the radiological features of multiple primary carcinoma (MPC) in the upper gastrointestinal (GI) tract, study its biological characteristics and evaluate X-ray examination in its diagnosis.

METHODS: Hypotonic double-contrast GI radiography was performed in 59 multiple primary carcinoma cases, pathologically proved by surgery or endoscopy biopsy. Radiological findings were analyzed.

RESULTS: Of the 59 cases, esophageal MPC (EMPC) was seen in 24, esophageal and gastric MPC (EGMPC) in 27 and gastric MPC (GMPC) in 8. Of the 49 lesions found in 24 EMPC, hyperplastic type was seen in 23, medullary type in 9. The lesions were located at the upper (n = 17), middle (n = 19) or lower (n = 13) segment of the esophagus. In 27 EGMPC, the esophageal lesions were located at the middle (n = 16) or lower (n = 11) segment of the esophagus, while the gastric lesions were located at the gastric cardia (n = 16), fundus (n = 1), body (n = 3) and antrum (n = 7). The esophageal lesions were mainly of the hyperplastic type (n = 12) or medullary type (n = 7), while the gastric lesions were mainly of the hyperplastic type (n = 18). A total of 119 lesions in the 59 patients with synchronous multiple carcinoma were proved by surgery or endoscopy biopsy, and preoperative upper radiographic examination detected 100 of them (84.03% sensitivity). Eighteen (52.94%) of the T₁ lesions were found during preoperative diagnosis by radiographic examination. Moreover, only 3 (3.53%) of the T_2-4 lesions were misdiagnosed.

CONCLUSION: Hypotonic double-contrast upper gastrointestinal examination, providing accurate information about lesion morphology, location and size, can serve as a sensitive technique for the preoperative diagnosis of MPC.