Endoscopic mucosal resection of early gastric cancer: Experiences in Korea

Development of an Artificial Intelligence Model for the Classification of Gastric Carcinoma Stages Using Pathology Slides

This study showcases a novel AI-driven approach to accurately differentiate between stage one and stage two gastric carcinoma based on pathology slide analysis. Gastric carcinoma, a significant contributor to cancer-related mortality globally, necessitates precise staging for optimal treatment planning and patient management. Leveraging a comprehensive dataset of 3540 high-resolution pathology images sourced from Kaggle.com, comprising an equal distribution of stage one and stage two tumors, the developed AI model demonstrates remarkable performance in tumor staging. Through the application of state-of-the-art deep learning techniques on Google's Collaboration platform, the model achieves outstanding accuracy and precision rates of 100%, accompanied by notable sensitivity (97.09%), specificity (100%), and F1-score (98.31%). Additionally, the model exhibits an impressive area under the receiver operating characteristic curve (AUC) of 0.999, indicating superior discriminatory power and robustness. By providing clinicians with an efficient and reliable tool for gastric carcinoma staging, this AI-driven approach has the potential to significantly enhance diagnostic accuracy, inform treatment decisions, and ultimately improve patient outcomes in the management of gastric carcinoma. This research contributes to the ongoing advancement of cancer diagnosis and underscores the transformative potential of artificial intelligence in clinical practice.

The risk of osteoporotic fracture in gastric cancer survivors: total gastrectomy versus subtotal gastrectomy versus endoscopic treatment

PURPOSES

Previous studies have suggested that there is an increased risk of osteoporotic fracture in gastric cancer survivors. However, the data was not classified according to surgery type. This study investigated the cumulative incidence osteoporotic fracture (OF) in gastric cancer survivors according to treatment modality.

METHODS

A total of 85,124 gastric cancer survivors during 2008-2016 were included. The type of surgery was classified as total gastrectomy (TG, n = 14,428)/subtotal gastrectomy (SG, n = 52,572)/endoscopic mucosal dissection and endoscopic mucosal resection (ESD/EMR, n = 18,125). The site of osteoporotic fractures included the spine, hip, wrist, and humerus. We examined cumulative incidence using Kaplan-Meier survivor analysis and cox proportional hazards regression analysis to determine the risk factor of OF.

RESULTS

The incidence of OF per 100,000 patient year was 2.6, 2.1, 1.8 in TG, SG, ESD/EMR group. The cumulative incidence rate was 2.3% at 3 years, 4.0% at 5 years, and 5.8% at 7 years in gastrectomy group, and 1.8% at 3 years, 3.3% at 5 years in the SG group, and 4.9% at 7 years postoperatively in ESD/EMR group. TG increased the risk of OF compared to patients who underwent SG (HR 1.75, 95% confidence interval [CI] 1.57-1.94), and ESD/EMR (hazard ratio [HR] 2.23, 95% CI 2.14-2.32).

CONCLUSION

Gastric cancer survivors who underwent TG had an increased osteoporotic fracture risk than did SG or ESD/EMR in these patients. The amount of gastric resection and accompanying metabolic changes seemed to mediate such risk. Additional research is needed to establish an optimal strategy for each type of surgery.

Machine learning-based gray-level co-occurrence matrix signature for predicting lymph node metastasis in undifferentiated-type early gastric cancer

BACKGROUND

The most important consideration in determining treatment strategies for undifferentiated early gastric cancer (UEGC) is the risk of lymph node metastasis (LNM). Therefore, identifying a potential biomarker that predicts LNM is quite useful in determining treatment.

AIM

To develop a machine learning (ML)-based integral procedure to construct the LNM gray-level co-occurrence matrix (GLCM) prediction model.

METHODS

We retrospectively selected 526 cases of UEGC confirmed through pathological examination after radical gastrectomy without endoscopic treatment in four tertiary hospitals between January 2015 to December 2021. We extracted GLCM-based features from grayscale images and applied ML to the classification of candidate predictive variables. The robustness and clinical utility of each model were evaluated based on the following factors: Receiver operating characteristic curve (ROC), decision curve analysis, and clinical impact curve.

RESULTS

GLCM-based feature extraction significantly correlated with LNM. The top 7 GLCM-based factors included inertia value 0° (IV_0), inertia value 45° (IV_45), inverse gap 0° (IG_0), inverse gap 45° (IG_45), inverse gap full angle (IG_all), Haralick 30° (Haralick_30), Haralick full angle (Haralick_all), and Entropy. The areas under the ROC curve (AUCs) of the random forest classifier (RFC) model, support vector machine, eXtreme gradient boosting, artificial neural network, and decision tree ranged from 0.805 [95% confidence interval (CI): 0.258-1.352] to 0.925 (95%CI: 0.378-1.472) in the training set and from 0.794 (95%CI: 0.237-1.351) to 0.912 (95%CI: 0.355-1.469) in the testing set, respectively. The RFC (training set: AUC: 0.925, 95%CI: 0.378-1.472; testing set: AUC: 0.912, 95%CI: 0.355-1.469) model that incorporates Entropy, Haralick_all, Haralick_30, IG_all, IG_45, IG_0, and IV_45 had the highest predictive accuracy.

CONCLUSION

The evaluation results indicate that the method of selecting radiological and textural features becomes more effective in the LNM discrimination against UEGC patients. Additionally, the ML-based prediction model developed using the RFC can be used to derive treatment options and identify LNM, which can hence improve clinical outcomes.

Correlation between healing type of lesion and recurrence in gastric neoplastic lesions after endoscopic submucosal dissection

BACKGROUND/AIMS

To date, there are few reports on the clinical association between healing pattern of lesion and local recurrence after endoscopic resection (ER). We examined the risk factors associated with local recurrence after endoscopic submucosal dissection (ESD) and the correlation between healing type of lesion and recurrence.

MATERIALS AND METHODS

We retrospectively analyzed medical records of 293 patients who underwent ESD of early gastric cancer or gastric adenoma between April 2010 and January 2012. We analyzed the relationship among factors such as age, location of lesion, size, pathologic diagnosis, presence of Helicobacter pylori (H. pylori), and healing types of ulcers in patients with local recurrence through follow-up endoscopic surveillance (1, 6, and 12 months after ESD).

RESULTS

We analyzed 141 patients except for patients who had not undergone surveillance endoscopy, H. pylori test, and ambiguous healing patterns. There were no significant correlations between local recurrences concerning sex, age, tumor size, location, and pathologic diagnosis. When the healing type of the ulcer was divided into hypertrophic polypoid type (9 cases (6.4%)), scar type (122 cases (86.5%)), and nodular type (10 cases (7.1%)), the scar type was found to be most common. A total of eight patients (5.7%) developed local recurrence, of which five were of nodular type and statistically significant (p=0.000).

CONCLUSION

The most common type of ulcer healing was scar type after ESD, but nodular type was associated with local recurrence. When we perform follow-up endoscopy after ESD, we should pay attention to the lesion that has nodular change of mucosal surface.

Endoscopic Resection of Undifferentiated-type Early Gastric Cancer

Early detection of gastric cancer is crucial because the survival rate can be improved through curative treatment. Although surgery and gastrectomy with lymph node dissection remain as the gold standard for curative treatment, early gastric cancer (EGC) with negligible risk of lymph node metastasis can be treated with endoscopic resection (ER), such as endoscopic submucosal dissection. Among gastric cancers, undifferentiated-type cancer is distinguished from differentiated-type cancer in various aspects in terms of clinical features and pathophysiology. The undifferentiated-type cancer is also known to be associated with an aggressive behavior and a poor prognosis. Therefore, the indication of ER for undifferentiated EGC is limited compared with differentiated-type. Recent studies have reported that ER for undifferentiated EGC is safe and shows favorable short- and long-term outcomes. However, it is necessary to understand the details of the research results and to selectively accept them. In this review, we aimed to evaluate the current practice guidelines and the short-term and long-term outcomes of ER for undifferentiated type EGC.

Endoscopic submucosal dissection for undifferentiated-type early gastric cancer: do we have enough data to support this?

Although endoscopic submucosal dissection (ESD) is now accepted for treatment of early gastric cancers (EGC) with negligible risk of lymph node (LN) metastasis, ESD for intramucosal undifferentiated type EGC without ulceration and with diameter ≤ 2 cm is regarded as an investigational treatment according to the Japanese gastric cancer treatment guidelines. This consideration was largely based on the analysis of surgically resected EGCs that contained undifferentiated type EGCs; however, results from several institutes showed some discrepancies in sample size and incidence of LN metastasis. Recently, some reports about the safety and efficacy of ESD for undifferentiated type EGC meeting the expanded criteria have been published. Nonetheless, only limited data are available regarding long-term outcomes of ESD for EGC with undifferentiated histology so far. At the same time, endoscopists cannot ignore the patients' desire to guarantee quality of life after the relatively non-invasive endoscopic treatment when compared to conventional surgery. To satisfy the needs of patients and provide solid evidence to support ESD for undifferentiated EGC, we need more delicate tools to predict undetected LN metastasis and more data that can reveal predictive factors for LN metastasis.

Long-term outcome after endoscopic submucosal dissection for early gastric cancer: focusing on a group beyond the expanded indication

OBJECTIVE

To determine the long-term outcome after endoscopic submucosal dissection (ESD) in patients with early gastric cancer (EGC) according to the pathological extent.

METHODS

ESD were performed in 280 patients with 309 EGC. The tumors were classified by pathological severity based on absolute indication (AI), expanded indication (EI) or beyond expanded indication (BEI). The therapeutic outcomes among the three groups were analyzed.

RESULTS

The complete resection rates of EGC were 96.4%, 78.7% and 41.2% in the AI-EGC, EI-EGC and BEI-EGC groups, respectively (P = 0.000). En bloc resection rates were 97.6%, 87.4% and 86.3% in the AI-EGC, EI-EGC and BEI-EGC groups, respectively (P = 0.023). The 5-year tumor recurrence rates were 1.8%, 1.5% and 15.4% in the AI-EGC, EI-EGC and BEI-EGC groups, respectively (P = 0.000). The 5-year disease-specific survival rates were 100%, 100% and 97.4% in the AI-EGC, EI-GEC and BEI-EGC groups, respectively (P = 0.088). The 5-year disease-free survival rates were 98.2%, 98.5% and 84.6% in the AI-EGC, EI-EGC and BEI-EGC groups, respectively (P = 0.000).

CONCLUSIONS

ESD was effective and safe in treating AI-EGC and EI-EGC, but there was a comparatively high rate of recurrence after ESD in the BEI-EGC group. However, long-term outcomes of patients with BEI-EGC that did not receive additional surgery were better than those with an natural course of EGC. Thus, ESD may be considered for specific BEI-EGC patients at high risk for surgery.

Can serum interleukin-2 receptor alpha predict lymph node metastasis in early gastric cancer?

Purpose

Although local resection like endoscopic mucosal resection for early gastric cancer is accepted as a treatment option, one of the most important drawbacks of such an approach is the inability to predictlymph node metastasis. The aim of this study was to evaluate the serum soluble receptor alpha for interleukin-2 (IL-2Rα) level as a predictor of lymph node metastasis in the patients with early gastric cancer.

Methods

Assessment of pre-operative serum IL-2Rα levels was performed on 86 patients with early gastric cancer treated by gastrectomies combined with D2 lymph node resections and 20 healthy controls at Samsung Medical Center. Data on patient age and gender, tumor size, depth of invasion, histologic differentiation, and endoscopic findings were reviewed post-operatively. The submucosal lesions were divided into three layers (sm1, sm2, and sm3) in accordance with the depth of invasion.

Results

Lymph node metastasis was observed in 16 patients (18.6%). Statistically, the serum IL-2Rα level was an important predictive factor of lymph node metastasis in undifferentiated gastric cancer, and the cut-off point for the predictive value of serum IL-2Rα level was 200 U/mL.

Conclusion

The serum IL-2Rα level might be a good predictor of lymph node metastasis in undifferentiated early gastric cancer.

Endoscopic treatment of large colorectal tumors: comparison of endoscopic mucosal resection, endoscopic mucosal resection-precutting, and endoscopic submucosal dissection

BACKGROUND

Endoscopic mucosal resection (EMR) is a useful therapeutic technique for colorectal tumors. However, for tumors larger than 20 mm, the chance of piecemeal resection is high. Recently introduced endoscopic submucosal dissection (ESD) enables en bloc resection regardless of the tumor size. This study aimed to compare the effectiveness and outcomes of EMR, EMR-precutting (EMR-P), and ESD in the treatment of colorectal tumors 20 mm in size or larger.

METHODS

This study reviewed 523 nonpedunculated colorectal tumors (499 patients) 20 mm or larger that received endoscopic treatment (EMR in 140 cases, EMR-P in 69 cases, and ESD in 314 cases) from January 2004 to November 2009.

RESULTS

The mean sizes of the tumors were 21.7 ± 3.5 mm (EMR), 23.5 ± 5.6 mm (EMR-P), and 28.9 ± 12.7 mm (ESD). The ratios of adenocarcinomas were 15.7% (EMR), 29% (EMR-P), and 37.9% (ESD). The en bloc resection rates were 42.9% (EMR), 65.2% (EMR-P), and 92.7% (ESD), and the complete resection rates were 32.9% (EMR), 59.4% (EMR-P), and 87.6% (ESD). Perforation occurred in 2.9% of the EMR-P cases and 8% of the ESD cases. The recurrence rates were 25.9% (EMR; median follow-up period, 26 months), 3.2% (EMR-P; median follow-up period, 16 months), and 0.8% (ESD; median follow-up period, 17 months).

CONCLUSION

For the treatment of large, nonpedunculated colorectal tumors, ESD is more effective than either EMR or EMR-P. Although ESD is technically demanding, it has clinical significance by overcoming the limitations of both EMR and EMR-P.

The feasibility and safety of the endoscopic submucosal dissection of superficial gastric neoplastic lesions in patients with compensated liver cirrhosis: a retrospective study

Background/Aims

When undergoing endoscopic submucosal dissection (ESD), patients with liver cirrhosis (LC) may suffer from a high risk of bleeding, bacteremia and tissue vulnerability. There have been few reports evaluating the efficacy and safety of ESD in patients with LC.

Methods

From January 2004 to March 2010, 23 patients with LC (cirrhosis group) underwent ESD for superficial gastric neoplastic lesions. The number of patients with a liver function in the Child-Pugh classes A and B were 20 and 3, respectively. The clinical outcomes and complications were compared with 69 patients without LC (control group) that were matched for age and sex.

Results

The en bloc resection, R0 resection and en bloc plus R0 resection rates of the cirrhosis group were 82.6%, 91.3%, and 82.6%, respectively, and did not show significant differences from the rates of the control group. No local recurrence was found in either group during the follow-up period. The procedure length of time (41.0 vs 39.0 minutes), rate of bleeding (4.3% vs 7.2%) and rate of perforation (0.0% vs 1.4%) in the cirrhosis group were also comparable to the results from the control group.

Conclusions

ESD was safely performed in patients with LC, and satisfactory outcomes were achieved with high en bloc and R0 resection rates for superficial gastric neoplastic lesions.

Outcome after endoscopic submucosal dissection for early gastric cancer in Korea

Endoscopic treatment, such as endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), has been established as one of the treatment options for selected cases with early gastric cancer (EGC). Most studies on this topic have been carried out by researchers in Japan. Recently, the experience in EMR/ESD for EGC outside Japan is increasingly reported. In Korea, gastric cancer is the most common malignant disease, and the second leading cause of cancer death. Currently, EMR for EGC is widely performed in many centers in Korea. Early results with a short-term follow-up period are very promising in Korea. The complete resection rate of EMR was 37.8%-94.3%, and that of ESD was 77.4%-93.1%. In this review, we will provide an overview of the outcomes of endoscopic treatments in Korea.

Management of the complications of endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is currently widely accepted as a standard treatment option for early gastrointestinal neoplasms in Korea. However, ESD has technical difficulties and a longer procedure time than conventional endoscopic resection. So it may have a higher risk of complications than conventional endoscopic resection techniques. We, the ESD study group of Korean Society of Gastrointestinal Endoscopy, have experienced many complications, mostly treated by endoscopic or conservative management. Here, we introduce and share our experiences for management of post ESD complications and review published papers on the topic.

Current status of endoscopic submucosal dissection for the management of early gastric cancer: A Korean perspective

The early diagnosis of gastric cancer allows patients and physicians to pursue the option of endoscopic resection, which is significantly less invasive than conventional surgical resection. In Korea, the use of endoscopic submucosal dissection (ESD) has been increasing, and many reports on ESD have been published. In addition, Korean gastroenterologists from several hospitals performing ESD have conducted formal meetings to discuss useful information regarding ESD. Here, we discuss the Korean experience with ESD, including outcomes and prospects of endoscopic treatments.

A case of congenital duodenal web causing duodenal stenosis in a down syndrome child: endoscopic resection with an insulated-tip knife

A 35-month-old girl visited our hospital with repetitive vomiting and abdominal distention; this was especially aggravated after the introduction of solid and semisolid foods. At 5 months of age, the patient, who had Down's syndrome, had undergone surgery for ventricular septal defect, atrial septal defect, and patent ductus arteriosus, and had subsequently been frequently hospitalized for respiratory infections and other viral infectious diseases. After her admission, the abdominal distension improved with fasting and intravenous fl uid therapy. Radiograph from a small-bowel series revealed a thin fi lling defect with a dilated duodenal bulb in the distal region of the second portion of the duodenum, suggesting a duodenal web, and endoscopy revealed duodenal stenosis. We therefore performed endoscopic resection with an insulated-tip knife because of the history of prior operations, fasting problems after operations, and respiratory infections. Seven days later, scar formation was noted on the second portion of the duodenum, the scope passed well at the excision site, and no retained food material was noted on the follow-up endoscopy. After the procedure, the patient's abdominal distention and repetitive vomiting subsided, and she was discharged with the ability to eat eat an age-appropriate normal diet. There were no specifi c symptoms or other complications for 1 year after the procedure.

Frequency and predictive factors of lymph node metastasis in mucosal cancer

Purpose

The incidence of lymph node metastasis has been reported to range from 2.6 to 4.8% in early stage gastric cancer with mucosal invasion (T1a cancer). Lymph node metastasis in early stage gastric cancer is known as an important predictive factor. We analyzed the prediction factors of lymph node metastasis in T1a cancer.

Materials and Methods

A total of 9,912 patients underwent radical gastrectomy due to gastric cancer from October 1994 to July 2006 in the Department Of Surgery at Samsung Medical Center. We did a retrospective analysis of 2,524 patients of these patients, ones for whom the cancer was confined within the mucosa.

Results

Among the 2,524 patients, 57 (2.2%) were diagnosed with lymph node metastasis, and of these, cancer staging was as follows: 41 were N1, 8 were N2, and 8 were N3a. Univariate analysis of clinicopathological factors showed that the following factors were significant predictors of metastasis: tumor size larger than 4 cm, the presence of middle and lower stomach cancer, poorly differentiated adenocarcinoma and signet-ring cell carcinoma, diffuse type cancer (by the Lauren classification), and lymphatic invasion. Multivariate analysis showed that lymphatic invasion and tumor larger than 4 cm were significant factors with P<0.001 and P=0.024, respectively.

Conclusions

The frequency of lymph node metastasis is extremely low in early gastric cancer with mucosal invasion. However, when lymphatic invasion is present or the tumor is larger than 4 cm, there is a greater likelihood of lymph node metastasis. In such cases, surgical treatments should be done to prevent disease recurrence.

A feasibility study on the expanded indication for endoscopic submucosal dissection of early gastric cancer

BACKGROUND

Endoscopic submucosal dissection (ESD) is the standard treatment for selected cases of early gastric cancer (EGC). Evolution of ESD techniques and accessories has expanded treatment indications. The aim of this study was to compare the therapeutic outcomes for conventional and expanded indications of ESD for EGC.

METHODS

Eight hundred six EGC lesions in 780 patients were classified into two groups based on a pathological review: a conventional indication group (595 cases) and an expanded indication group (211 cases). The expanded indication group was classified further into subgroups according to tumor depth and tumor size. Therapeutic outcomes were compared between the conventional and expanded indication groups and between the expanded indication subgroups.

RESULTS

The complete resection rate (97.3% vs. 81.0%, p<0.001) and en bloc complete resection rate (95.6% vs. 79.1%, p=0.003) were higher in the conventional indication group than in the expanded indication group. Among the expanded indication patients, the complete resection rate (64.5% vs. 91.1%, p<0.001) and en bloc complete resection rate (63.2% vs. 89.6%, p<0.001) were lower in the submucosal invasion subgroup than in the mucosal invasion subgroup. The complete resection rate and en bloc complete resection rate did not differ between subgroups classified according to tumor size in the expanded indication group. The conventional indication group and expanded indication group did not differ with regard to the rates of local recurrence (0.7% vs. 0%), metachronous recurrence (3.6% vs. 3.3%), or cumulative disease-free survival. Survival outcome was similar in the subgroups classified by tumor depth and size. Perforation was more frequent in the expanded indication group than in the conventional indication group (6.6% vs. 2.4%, p<0.001).

CONCLUSION

ESD for expanded indication of EGC had acceptable clinical outcomes. ESD can be applied safely to properly selected patients with EGC.

A feasibility study on the expanded indication for endoscopic submucosal dissection of early gastric cancer

BACKGROUND

Endoscopic submucosal dissection (ESD) is the standard treatment for selected cases of early gastric cancer (EGC). Evolution of ESD techniques and accessories has expanded treatment indications. The aim of this study was to compare the therapeutic outcomes for conventional and expanded indications of ESD for EGC.

METHODS

Eight hundred six EGC lesions in 780 patients were classified into two groups based on a pathological review: a conventional indication group (595 cases) and an expanded indication group (211 cases). The expanded indication group was classified further into subgroups according to tumor depth and tumor size. Therapeutic outcomes were compared between the conventional and expanded indication groups and between the expanded indication subgroups.

RESULTS

The complete resection rate (97.3% vs. 81.0%, p<0.001) and en bloc complete resection rate (95.6% vs. 79.1%, p=0.003) were higher in the conventional indication group than in the expanded indication group. Among the expanded indication patients, the complete resection rate (64.5% vs. 91.1%, p<0.001) and en bloc complete resection rate (63.2% vs. 89.6%, p<0.001) were lower in the submucosal invasion subgroup than in the mucosal invasion subgroup. The complete resection rate and en bloc complete resection rate did not differ between subgroups classified according to tumor size in the expanded indication group. The conventional indication group and expanded indication group did not differ with regard to the rates of local recurrence (0.7% vs. 0%), metachronous recurrence (3.6% vs. 3.3%), or cumulative disease-free survival. Survival outcome was similar in the subgroups classified by tumor depth and size. Perforation was more frequent in the expanded indication group than in the conventional indication group (6.6% vs. 2.4%, p<0.001).

CONCLUSION

ESD for expanded indication of EGC had acceptable clinical outcomes. ESD can be applied safely to properly selected patients with EGC.

Endoscopists' view on superficial spreading type of early gastric cancer--endoscopic resection or surgery?

OBJECTIVE

The superficial spreading type of early gastric cancer (EGC) possesses unique features different from other types of EGC. We aimed to elucidate the clinicopathological features of superficial spreading type of EGC.

MATERIAL AND METHODS

We analyzed 1455 EGC lesions from 1398 patients who had undergone surgical treatment at Samsung Medical Center from 2000 to 2002. Then the clinicopathological features of 224 superficial-spreading EGC lesions (15.4%) was compared to that of 1231 lesions of a common type of EGC.

RESULTS

In the superficial spreading type of EGC, the incidence of undifferentiated type and submucosal invasion were higher than those of common type of EGC (55.4 vs 38.0%, p < .01 and 58.5 vs 37.8%, p < .01, respectively). Lymph node metastasis and lymphovascular invasion were more frequent in superficial spreading type than in common type of EGC (19.2 vs 7.6%, p < .01 and 15.2 vs 7.4%, p < .01, respectively). There was no difference in recurrence rate or 5-year survival rate between the two groups.

CONCLUSION

Considering higher risk of submucosal invasion and lymph node metastasis in superficial spreading type, a careful consideration should be done before the application of endoscopic resection to the superficial spreading type of EGC.

Efficacy and safety of endoscopic submucosal dissection for early gastric cancer in patients with comorbid diseases

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD), a new and potentially curative method for treating gastrointestinal neoplasms, may have longer procedure time and the risk of complications when compared to conventional endoscopic mucosal resection. This study evaluated the efficacy and safety of ESD in patients with comorbid diseases.

METHODS

The outcomes of 337 patients who underwent ESD for early gastric cancer at Samsung Medical Center from April 2003 to December 2006 were analyzed retrospectively. The Charlson comorbidity scale was used to divide the patients into low-risk (no risk factor) and high-risk (at least one risk factor) groups. The outcomes and complications were compared between the high- and low-risk groups.

RESULTS

The low- and high-risk groups comprised 240 and 97 patients with mean ages of 61.1 and 64.7 years, respectively (p=0.002). Tumor location, tumor size, depth of invasion, procedure duration, and rates of en bloc resection, complete resection, complication, and recurrence did not differ significantly between the two groups (p>0.05).

CONCLUSIONS

ESD may be a safe and effective treatment for early gastric cancer in patients with comorbid diseases.

Rebamipide may be comparable to H2 receptor antagonist in healing iatrogenic gastric ulcers created by endoscopic mucosal resection: a prospective randomized pilot study

Endoscopic mucosal resection (EMR) results in the formation of iatrogenic gastric ulcers and the optimal treatments for such ulcers are still unclear. We aimed to evaluate the efficacy of rebamipide in the management of EMR-induced ulcers by comparing it with an H(2) receptor antagonist. After EMR, patients were randomly assigned into either rebamipide or famotidine groups. All patients received a one-week lansoprazole 30 mg q.d. therapy followed by three-week famotidine (20 mg b.i.d.) or rebamipide (100 mg t.i.d.) therapy. Four weeks after the treatments, ulcer sizes, stages, bleeding rates, and ulcer-related symptoms were compared using endoscopy and a questionnaire. A total of 63 patients were enrolled in this study. Finally, 51 patients were analyzed, 26 in rebamipide and 25 in famotidine group. Baseline characteristics were not significantly different between the two groups. Four weeks after EMR, the two groups were comparable in terms of ulcer reduction ratio (P=0.297), and ulcer stage (P=1.000). Moreover, no difference was observed with regard to ulcer-related symptoms, drug compliance, adverse drug event rates, and bleeding rates. Our data suggest that rebamipide is not inferior to famotidine in healing iatrogenic gastric ulcers, and could be a therapeutic option in the treatment of such ulcers.

Successful outcomes of endoscopic resection for gastric adenomas and early cancers located on the pyloric ring (with video)

BACKGROUND

Endoscopic resection is difficult to perform in patients who have gastric neoplasms located on the pyloric ring, especially for lesions that extend from the pyloric area to the duodenal bulb, where it is difficult to retroflex the endoscope, and the risk of perforation is increased.

OBJECTIVE

To assess the results of endoscopic resection of early gastric neoplasms located on the pyloric ring.

DESIGN

Case series.

SETTING

Tertiary-care referral center.

PATIENTS

This study involved 16 patients with 5 gastric adenomas and 11 early cancers that were located on the pyloric ring.

INTERVENTIONS

After a retroflexion trial within the duodenum for evaluation of tumor extension from the pyloric area to the duodenal bulb, en bloc resection was attempted. Endoscopic submucosal dissection was attempted at the duodenal bulb with an endoscope retroflexed for cases of duodenal invasion.

MAIN OUTCOME MEASUREMENTS

The curative resection rate, en bloc resection rate, and complications were determined.

RESULTS

The success rate of retroflexion within the duodenum was 88% (14 of 16). The curative resection rate was 81.3% (13 of 16), and the en bloc resection rate was 75% (12 of 16). En bloc resection was possible for 3 of 4 (75%) cases of duodenal bulb extension. Major procedure-related complications were not encountered.

LIMITATIONS

Small number of patients.

CONCLUSION

Endoscopic resection appears to be a feasible and effective treatment for early gastric neoplasms located on the pyloric ring, including lesions that extend from the pyloric area to the duodenal bulb.

Clinical outcomes of endoscopic submucosal dissection (ESD) for treating early gastric cancer: comparison with endoscopic mucosal resection after circumferential precutting (EMR-P)

BACKGROUND

To achieve en bloc resection for large lesions, endoscopic mucosal resection after circumferential precutting and endoscopic submucosal dissection techniques have been developed.

AIM

To compare endoscopic submucosal dissection with endoscopic mucosal resection after circumferential precutting in terms of the clinical efficacy and safety.

PATIENTS AND METHODS

346 consecutive patients underwent their first endoscopic mucosal resection after circumferential precutting (103 patients) or endoscopic submucosal dissection (243 patients) for early gastric cancer and their clinical outcomes were compared.

RESULTS

For early gastric cancer >or=20mm endoscopic submucosal dissection group demonstrated significantly higher en bloc resection and en bloc plus R0 resection rate compared with endoscopic mucosal resection after circumferential precutting group. For early gastric cancer with size of 10-19 mm, endoscopic submucosal dissection group also showed significantly higher en bloc resection rate. For early gastric cancer <20mm, however, en bloc plus R0 resection rate for endoscopic mucosal resection after circumferential precutting group was comparable to that for endoscopic submucosal dissection group. In case of R0 resection of intramucosal differentiated cancer, neither group showed local recurrence during the median 29 and 17 months of follow-up. Two groups did not show significant difference in the bleeding or perforation rates.

CONCLUSION

For early gastric cancer <20mm endoscopic mucosal resection after circumferential precutting may be considered as an alternative choice to endoscopic submucosal dissection. However, for early gastric cancer >or=20mm endoscopic submucosal dissection should be considered as the first choice for treating early gastric cancer.

Perspective on the practical indications of endoscopic submucosal dissection of gastrointestinal neoplasms

Endoscopic submucosal dissection (ESD) is a new endoluminal therapeutic technique involving the use of cutting devices to permit a larger resection of the tissue over the muscularis propria. The major advantages of the technique in comparison with polypectomy and endoscopic mucosal resection are controllable resection size and shape and en bloc resection of a large lesion or a lesion with ulcerative findings. This technique is applied for the endoscopic treatment of epithelial neoplasms in the gastrointestinal tract from the pharynx to the rectum. Furthermore, some carcinoids and submucosal tumors in the gastrointestinal tract are treated by ESD. To determine the indication, two aspects should be considered. The first is a little likelihood of lymph node metastasis and the second is the technical resectability. In this review, practical guidelines of ESD for the gastrointestinal neoplasms are discussed based on the evidence found in the literature.