Endoscopic mucosal resection in the stomach using the insulated-tip needle-knife

Endoscopic mucosal resection-precutting vs conventional endoscopic mucosal resection for sessile colorectal polyps sized 10-20 mm

BACKGROUND

The optimal method to remove sessile colorectal lesions sized 10-20 mm remains uncertain. Piecemeal and incomplete resection are major limitations in current practice, such as endoscopic mucosal resection (EMR) and cold or hot snare polypectomy. Recently, EMR with circumferential precutting (EMR-P) has emerged as an effective technique, but the quality of current evidence in comparative studies of conventional EMR (CEMR) and EMR-P is limited.

AIM

To investigate whether EMR-P is superior to CEMR in removing sessile colorectal polyps.

METHODS

This multicenter randomized controlled trial involved seven medical institutions in China. Patients with colorectal polyps sized 10-20 mm were enrolled and randomly assigned to undergo EMR-P or CEMR. EMR-P was performed following submucosal injection, and a circumferential mucosa incision (precutting) was conducted using a snare tip. Primary outcomes included a comparison of the rates of en bloc and R0 resection, defined as one-piece resection and one-piece resection with histologically assessed clear margins, respectively.

RESULTS

A total of 110 patients in the EMR-P group and 110 patients in the CEMR group were finally evaluated. In the per-protocol analysis, the proportion of en bloc resections was 94.3% [95% confidence interval (CI): 88.2%-97.4%] in the EMR-P group and 86% (95%CI: 78.2%-91.3%) in the CEMR group (P = 0.041), while subgroup analysis showed that for lesions > 15 mm, EMR-P also resulted in a higher en bloc resection rate (92.0% vs 58.8% P = 0.029). The proportion of R0 resections was 81.1% (95%CI: 72.6%-87.4%) in the EMR-P group and 76.6% (95%CI: 68.8%-84.4%) in the CEMR group (P = 0.521). The EMR-P group showed a longer median procedure time (6.4 vs 3.0 min; P < 0.001). No significant difference was found in the proportion of patients with adverse events (EMR-P: 9.1%; CEMR: 6.4%; P = 0.449).

CONCLUSION

In this study, EMR-P served as an alternative to CEMR for removing nonpedunculated colorectal polyps sized 10-20 mm, particularly polyps > 15 mm in diameter, with higher R0 and en bloc resection rates and without increasing adverse events. However, EMR-P required a relatively longer procedure time than CEMR. Considering its potential benefits for en bloc and R0 resection, EMR-P may be a promising technique in colorectal polyp resection.

Risk Factors Indicating Difficulty During Gastric Endoscopic Submucosal Dissection for Inexperienced Endoscopists: A Retrospective Study

AIM

Factors that may make endoscopic submucosal dissection (ESD) difficult for operators have been evaluated according to results based on the performance of experienced endoscopists. This study aimed to verify the predictors of difficult gastric ESD for ESD beginners.

METHODS

From January 2015 to December 2021, 466 superficial gastric neoplasms were treated with ESD at Showa University Hospital. Excluding 103 lesions that performed ESD by experts who experienced more than 80 ESDs, a total of 363 lesions were included. The lesions were divided into two groups according to the ESD performance experience of the operator: ESD beginner (EB; ESD experience≤30 cases) and ESD intermediate (EI; ESD experience 31-80 cases) groups. Relationships between difficult ESD (having at least one of the following: procedure time>60 min, incomplete resection, change of operator, and occurrence of severe complications) and clinicopathological findings of the lesion were analyzed.

RESULTS

The complete resection rates and the difficult ESD rates in the EB and EI groups were 99.3%, 94.8%, and 61.2%, 50.7%, respectively. In the EB group, univariate analysis showed that difficult ESD rate was significantly higher in the non-lower third lesions, the lesser curvature lesions, and cancerous lesions. In the EI group, univariate analysis showed that difficult ESD rate was significantly higher in lesion with ≥20 mm size, lesser curvature lesions, lesions with ulcers, and submucosal cancers. Multivariate analysis showed that the lesser curvature location and cancerous histology in the EB group and ≥20 mm lesion size, the lesser curvature location and submucosal invasion in the EI group were independent predictors of difficult ESD.

CONCLUSIONS

The lesser curvature location is recognized as independent ESD difficulty factor for both beginners and intermediates. Cases with lesions located in the lesser curvature should not be selected for gastric ESD training by beginners.

Double-clip traction for colonic endoscopic submucosal dissection: a multicenter study of 599 consecutive cases (with video)

BACKGROUND AND AIMS

Colonic endoscopic submucosal dissection (ESD) is particularly challenging and limited to a few expert centers. We recently conducted a pilot study on improvement of colonic ESD with systematic use of a countertraction device (double-clip traction with rubber band [DCT-ESD]).

METHODS

A French prospective multicenter study was conducted between March 2017 and September 2019, including all consecutive cases of naive colonic ESD. Since the first case of DCT-ESD in March 2017, all cases of colonic ESD have been performed using the DCT-ESD strategy in the 3 centers involved in the study.

RESULTS

Five hundred ninety-nine lesions with a mean size of 53 mm were included in this study, resected by 5 operators in 3 centers. The en bloc, R0, and curative resection rates were 95.7%, 83.5%, and 81.1%, respectively. The adverse event rates were 4.9% for perforation and 4.2% for postprocedure bleeding. Between 2017 and 2019, the rates of R0 and curative resections increased significantly from 74.7% in 2017 to 88.4% in 2019 (P = .003) and from 72.6% in 2017 to 86.3% in 2019 (P = .004), respectively. Procedure duration and speed of resection were 62.4 minutes and 39.4 mm²/minute, respectively. No differences were noted between operators.

CONCLUSION

DCT-ESD is a safe and reproducible technique, with results comparable with those of the large Japanese teams with speed of resection twice as high as previously reported studies. The DCT strategy is promising, cheap, and seems to be reproducible. Physicians performing colonic ESD should be aware of this promising tool to improve their results in ESD.

Effect on Bleeding Prevention of an Intravenous Proton Pump Inhibitor During the Fasting Period After Endoscopic Submucosal Dissection: a Prospective, Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND

No consensus has been achieved on optimal perioperative strategies for patients undergoing endoscopic submucosal dissection (ESD). The aim of this study was to investigate the effects of an intravenous (IV) proton pump inhibitor (PPI) given during the fasting period after ESD on delayed bleeding following ESD.

METHODS

This study was designed as a prospective, randomized, double-blind, placebo-controlled trial in a single center. A total of 235 patients who underwent ESD for adenoma and early gastric cancer between March 2016 and September 2018 were randomized into a PPI group and placebo group. Patients were administrated intravenous pantoprazole 40 mg daily (PPI group) or placebo (placebo group) during the fasting period 48 h after ESD (from the day of ESD to the following day, 48 h). After oral feeding (48 h after ESD), oral PPI was given to both groups for 8 weeks.

RESULTS

Among 235 patients in the intention-to-treat (ITT) and 195 in the per-protocol (PP) analysis, there was no significant difference between the PPI and control groups in major bleeding (PPI vs. placebo; 3.3% vs. 1.7%, p = 0.27) or minor bleeding (PPI vs. placebo; 7.6% vs. 4.3%, p = 0.41) after ESD. There was no significant difference in age (p = 0.28), histology (p = 0.75), tumor size (p = 0.48), or procedure time (p = 0.49) between the two groups. The only independent risk factor for major delayed bleeding was the combined use of aspirin and antiplatelet agent (OR; 12.25, 95% CI; 1.06-141.19, p = 0.04).

CONCLUSIONS

Administration of routine IV PPI during the fasting period 48 h after ESD does not reduce delayed post-ESD bleeding.

Current state of education and training for endoscopic submucosal dissection: Translating strategy and success to the USA

Endoscopic submucosal dissection (ESD) is a rigorous and technically sophisticated method for removal of lesions within the gastrointestinal tract. Despite having advantages of en-bloc resection of lesions, regardless of size, and widespread use in Japan and Asia, ESD has not become widely adopted in the USA for a variety of reasons. Based upon Japanese education and the master-apprentice model, modification to the education system and additional techniques designed to facilitate broader adoption are required for trainees in the USA. This article will review the current state of education and training for ESD in the USA.

Vonoprazan Fumarate for the Treatment of Gastric Ulcers: A Short Review on Emerging Data

Potassium-competitive acid blockers (P-CABs), such as vonoprazan, represent a novel and heterogeneous class of drugs that competitively block the potassium binding site of gastric H+/K+ ATPase, thus potentially overcoming the limitations of proton-pump inhibitors. Different studies evaluated the efficacy of vonoprazan versus proton-pump inhibitors (PPIs) for the treatment of acid-related disorders, and, therefore, P-CABs present the same indications of PPIs: gastroesophageal reflux disease, gastric and duodenal ulcer healing, management of upper gastrointestinal bleeding, non-steroidal anti-inflammatory drug (NSAID)-associated ulcers and Helicobacter pylori eradication therapy. The aim of this review was to evaluate the role of vonoprazan for the treatment of peptic ulcer disease (PUD) and the management of gastric ulcer occurring after endoscopic submucosal dissection (ESD). Indeed, vonoprazan (at the dose of both 10 and 20mg) showed similar results to PPIs in patients taking long-term NSAIDs, in the absence of severe adverse effects, and provided a more rapid and effective treatment of ulcers induced by ESD. However, studies in medical literature are heterogeneous, mainly performed with a retrospective design, and often carried out in Japan only. For these reasons, further prospective, randomized studies are warranted in order to help physicians, patients, and policymakers regarding the use of vonoprazan in clinical practice.

Multibending scope use for reduction of perforation risks in endoscopic submucosal dissection

AIMS

To identify areas that are difficult to access by the single scope at the time of endoscopic submucosal dissection (ESD) and examine the effectiveness, en-bloc, R0 resection, and perforation rate after changing to multibending scope at the same site.

MATERIAL AND METHODS

When the direct visualization of the submucosal layer became impossible with Q260J or in the position where the device became vertical and peeling became impossible in parallel, we decided to change to the multibending 2TQ260M scope to record the position where the change was effective and the perforation rate.

RESULTS

A total of 315 lesions were studied. Of the 12 sites, ESD was completed using the Q260J alone at four sites. The 2TQ260M scope was used with greater frequency at the fornix (88.9%) and on the line of the lesser curvature of the stomach (37.1%). In the cases with observed perforations (0.9%), the submucosal layer was not elevated due to the adhesion caused by strong fibrosis. None of the cases involving the change to 2TQ260M was ineffective, nor were perforations observed, and all resected specimens were en-bloc and R0 resections.

CONCLUSIONS

The success rate of this scope may help clinicians perform ESD with greater understanding.

Margin diagnosis for endoscopic submucosal dissection of early gastric cancer using multiphoton microscopy

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) has become the primary option for the treatment of early gastric cancer (EGC). Thus, it is necessary to diagnose whether residual cancer cells exist in the ESD specimen margins, which can affect tumor recurrence and survival rates in the future. Multiphoton microscopy (MPM) can be suitably used for nondestructive imaging of biological tissue on a cellular level to enable real-time guidance during endoscopic therapy. Considering this, the objective of this study is to explore the practicality of MPM for the diagnosis of ESD specimen margins in the case of EGC.

METHODS

First, a total of 20 surgical samples was imaged using the proposed MPM technique to obtain two-photo excited fluorescence signal from the intrinsic fluorescent substances within cells and second-harmonic generation signal from collagen; these signals were used to determine MPM pathological features for margin diagnosis. Then, a double-blind study of 50 samples was conducted to evaluate the diagnosis results based on the obtained MPM pathological features.

RESULTS

Multiphoton microscopy can accurately identify the cytological and morphological differences between tissue in the negative and positive margin. The sensitivity, specificity, accuracy, negative predictive, and positive predictive values of MPM in the diagnosis of ESD specimen margins were 97.62, 75.00, 94.00, 95.35, and 85.71%, respectively.

CONCLUSION

These results indicate that MPM can be used as an effective, real-time, and label-free novel method to determine intraoperative resection margins.

Randomized Controlled Trial Comparing the Effects of Vonoprazan Plus Rebamipide and Esomeprazole Plus Rebamipide on Gastric Ulcer Healing Induced by Endoscopic Submucosal Dissection

Objective Gastric endoscopic submucosal dissection (ESD) is currently a standard procedure, and proton pump inhibitors (PPIs) are most commonly used to treat post-ESD ulcers. Vonoprazan, a potassium-competitive acid blocker (P-CAB), reportedly inhibits gastric acid secretions more effectively than PPIs. Combination therapy of a PPI plus rebamipide is effective for treating larger ulcers. Our goal was to evaluate the effects of vonoprazan plus rebamipide compared to esomeprazole plus rebamipide for the treatment of post-ESD ulcers. Methods First, vonoprazan plus rebamipide (V group) or esomeprazole plus rebamipide (E group) was orally administered to subjects for eight weeks. We then evaluated the ulcer healing process at four and eight weeks after the procedure using a gastric ulcer stage system and by measuring the ulcer size. Patients A total of 84 patients who underwent ESD for gastric neoplasms between September 2015 and December 2017 in Tsuchiura Kyodo General Hospital were included in this randomized controlled trial. Results The ulcer scar rates at week 4 in the V group (n=43) and E groups (n=39) were 20.9% and 15.4%, while those at week 8 were 90.7% and 92.3%, respectively. The ulcer reduction rates at week 4 in the V and E groups were 94.6% and 93.8%, and those at week 8 were 99.7% and 99.3%, respectively. The ulcer scar rates and reduction rates were not significantly different between the two groups. Conclusion Combination therapy consisting of vonoprazan plus rebamipide was not superior to that of esomeprazole plus rebamipide for post-ESD ulcer healing (UMIN000019516).

Flexible robotic endoscopy: current and original devices

Two current major research topics concern the incorporation of flexible robotic endoscopy systems developed for natural-orifice translumenal endoscopic surgery (NOTES), primarily for the purpose of remote forceps operation, into endoscopic submucosal dissection (ESD) and other flexible endoscopic treatments and the use of robots for the manipulation of flexible endoscopes themselves with the aim of enabling the remote insertion of colonoscopes, etc. However, there are still many challenges that remain to be addressed; the ideal robotic endoscope has not yet been realized. This article reviews the ongoing developments and our own efforts in the area of flexible robotic endoscopy.

Procedure Time for Gastric Endoscopic Submucosal Dissection according to Location, considering Both Mucosal Circumferential Incision and Submucosal Dissection

Background. Previous assessments of technical difficulty and procedure time for endoscopic submucosal dissection (ESD) of gastric neoplasms did not take into account several critical determinants of these parameters. However, two key phases of ESD determine the total procedure time: the mucosal circumference incision speed (CIS) and submucosal dissection speed (SDS). Methods. We included 302 cases of en bloc and R0 resection of gastric neoplasms performed by 10 operators who had completed the training program at our hospital. Twelve locations were classified based on multiple criteria, such as condition of surrounding mucosa, lesion vascularity, presence of submucosal fat, ulcers, scars, fibrosis, and scope and device maneuverability. Lesions in different locations were classified into three groups based on the length of the procedure: fast, moderate, or late. Results. A significant difference was found in CIS and SDS for each location (p < 0.01), which demonstrates the validity of this classification system. In several locations, CIS and SDS were not consistent with each other. Conclusion. CIS and SDS did not correspond to each other even for lesions in the same location. Consideration of ESD procedure time for gastric neoplasms requires a more elaborate classification system than that previously reported.

Effects of esomeprazole on the healing process of post-endoscopic submucosal dissection gastric ulcers: a single arm, prospective trial

Objectives: Gastric endoscopic submucosal dissection (ESD) is currently a standard procedure. ESD enables en-bloc resection of large lesions, while inducing larger artificial ulcers to a greater extent than conventional procedures. Several studies have reported that proton pump inhibitors (PPIs) prevent delayed bleeding and expedite the artificial ulcer healing process. Esomeprazole, an S-isomer of omeprazole, is reportedly one of strongest inhibitors of gastric acid secretion. Previous studies have examined the effectiveness of esomeprazole. Our goal was to verify the effects of esomeprazole on artificial ulcers in a prospective study.

Methods: A total of 185 patients underwent ESD for gastric neoplasms at our hospital between January 2013 and June 2015. Among these 185 patients, 49 post-ESD scar lesions were included in this prospective trial. First, 20 mg esomeprazole was orally administered to all subjects before and after the procedure. We then evaluated the delayed bleeding rate and ulcer scarring rates at 4 weeks and 8 weeks after the procedure by using a gastric ulcer stage system.

Results: There was one case of delayed bleeding (2.0%). Regardless of Helicobacter pylori infection status, ulcer scarring rates at weeks 4 and 8 were respectively 28.6% (14/49) and 98% (48/49).

Conclusions: Our results suggest that oral administration of esomeprazole alone may be sufficient for prompt healing of artificial gastric ulcers induced by ESD (UMIN000009367).

Endoluminal Therapy in Colorectal Cancer

Appropriate endoscopic resection for colorectal polyps can present a challenge to endoscopists, as these lesions may harbor malignancy. With recent advances in endoscopy, however, we are now entering an exciting frontier of endoscopic therapy for gastrointestinal lesions. These techniques include endoluminal mucosal resection and endoscopic submucosal dissection, which may be utilized on several colonic lesions. This article will discuss these principle endoscopic techniques, their outcomes, and briefly highlight their influence on endoscopic interventions, including transanal endoscopic microsurgery and natural orifice transluminal endoscopic surgery.

Endoscopic therapy for early gastric cancer: Standard techniques and recent advances in ESD

The technique of endoscopic submucosal dissection (ESD) is now a well-known endoscopic therapy for early gastric cancer. ESD was introduced to resect large specimens of early gastric cancer in a single piece. ESD can provide precision of histologic diagnosis and can also reduce the recurrence rate. However, the drawback of ESD is its technical difficulty, and, consequently, it is associated with a high rate of complications, the need for advanced endoscopic techniques, and a lengthy procedure time. Various advances in the devices and techniques used for ESD have contributed to overcoming these drawbacks.

Gastric heterotopia of rectum in a child: a mimicker of solitary rectal ulcer syndrome

Bleeding per rectum is an uncommon presentation in pediatric patients. Heterotopic gastric mucosa in the rectum is a rare cause of rectal bleeding. Here, we report a 3-year-old child with a bleeding rectal ulcer that was initially diagnosed and managed as a solitary rectal ulcer syndrome. After 1 month, the patient persisted to have intermittent rectal bleed and severe anal pain. Repeat colonoscopy showed the worsening of the rectal ulcer in size. Pediatric surgeon excised the ulcer, and histopathological examination revealed a gastric fundic-type mucosa consistent with the diagnosis of gastric heterotopia of the rectum. Over the following 18 months, our patient had experienced no rectal bleeding and remained entirely asymptomatic. In conclusion, heterotopic gastric mucosa of the rectum should be considered in the differential diagnosis of a bleeding rectal ulcer.

Gastric endoscopic submucosal dissection: From animal model to patient

AIM: To assess whether the use of porcine models is useful for learning endoscopic submucosal dissection (ESD), thus contributing to its subsequent application in human patients.

METHODS: This study/learning process was carried out in 3 phases: Phase I: Ex vivo animal; Phase II: In vivo animal; Phase III: Humans. One endoscopist performed 30 gastric ESDs in porcine models, and later 5 gastric ESDs in 5 patients. The ESD was done following the method practiced at the National Cancer Center in Tokyo, Japan. Technical aspects, size, time and speed of ESD, as well as complications were registered. In patients, their clinical, endoscopic and histologic evolution was additionally added.

RESULTS: Thirty en bloc ESDs were carried out in animal models. The mean ± SD size of the pieces was of 28.4 ± 1.2 mm, and the time of ESD was 41.7 ± 2.4 min. The time of ESD in the first 15 procedures was 43.0 ± 3.0 min whereas in the next 15 procedures, the time was 40.3 ± 3.9 min, P = 0.588. The speed in the first 15 ESDs was 1.25 ± 0.11 cm²/min vs 2.12 ± 0.36 cm²/min in the remaining 15, P = 0.028. There were no complications. In patients, 5 lesions were resected en bloc. The size of the pieces was 25.2 ± 5.1 mm and the time was 85.0 ± 25.6 min. Endoscopic and histological controls did not show evidence of residual neoplastic tissue.

CONCLUSION: A sequential ESD training program of a unique endoscopist, based on the practice in porcine models, contributed to learning ESD for its subsequent application in humans, yielding good results in efficacy and safety.

Comparison of clinical outcomes among different endoscopic resection methods for treating colorectal neoplasia

BACKGROUND/AIM

Endoscopic treatments of colorectal neoplasms have yet to be standardized. This study aimed to compare efficacy and tolerability of different endoscopic resection methods for colorectal epithelial tumors.

METHODS

Patients with non-pedunculated colorectal tumors undergoing endoscopic treatments were consecutively enrolled, and their medical records were reviewed retrospectively. The resection methods were classified into three groups: endoscopic mucosal resection with circumferential precutting (EMR-P), endoscopic submucosal dissection with snaring (ESD-S), and endoscopic submucosal dissection alone (ESD). We compared en bloc resection, pathological complete resection, and complications associated with these methods.

RESULTS

Overall, 206 lesions from 203 patients were included in the study (mean size 25.2 ± 10.1 mm). The number of lesions treated with EMR-P, ESD-S, and ESD was 91 (44.2 %), 57 (27.7 %), and 58 (28.2 %), respectively. There was a significant difference in both the en bloc resection rates (EMR-P, 61.5 %; ESD-S, 64.9 %; ESD, 96.6 %; p = 0.001) and complete resection rates (EMR-P, 51.6 %; ESD-S, 54.4 %; ESD, 75.9 %; p = 0.009). Bleeding and perforation were less frequently observed in the EMR-P group. In the subgroup-analysis of lesions less than 20 mm, however, these differences were not observed.

CONCLUSIONS

All endoscopic resection methods, including EMR-P, ESD-S, and ESD, were effective and safe for the treatment of colorectal neoplasms. Technically demanding ESD with high en bloc and complete resection rate should be reserved for the suspicious cancer lesion, which requires the precise histological evaluation. EMR-P with good feasibility can be considered an alternative to ESD for the lesions less than 20 mm.

A Case-Control Study of Esomeprazole Plus Rebamipide vs. Omeprazole Plus Rebamipide on Post-ESD Gastric Ulcers

Objectives

Endoscopic submucosal dissection (ESD) is useful for treating gastric tumors. Several trials have shown the efficacy of 4 or 8 weeks of proton pump inhibitor (PPI) administration for post-ESD ulcers. However, if the size of the post-ESD ulcer is larger than predicted, PPI administration alone might not be sufficient for the ulcer to heal within 4 weeks. There is no report about the efficacy of post-ESD gastric ulcers by esomeprazole. We examined retrospectively the efficacy of a combination therapy of esomeprazole plus rebamipide, a mucosal-protective antiulcer drug, on the acceleration of post-ESD ulcer healing comparing with omeprazole plus rebamipide.

Methods:

We reviewed the medical records of patients who underwent ESD for gastric neoplasia. We conducted a case-control study to compare the healing rates within 4 weeks effected by esomeprazole plus rebamipide (group E) and omeprazole plus rebamipide (group O). The sizes of the artificial ulcers were divided into normal-sized or large-sized.

Results:

The baseline characteristics did not differ significantly between the two groups except age and sex. Stage S1 disease was observed in 27.6% and 38.7% of patients after 4 weeks of treatment in the group E and O, respectively. In large-sized artificial ulcers, the healing rate of stage S1 in group E is significantly higher than that in group O in 4 weeks.(25% VS 0%:P = 0.02)

Conclusions:

The safety and efficacy profiles of esomeprazole plus rebamipide and omeprazole and rebamipide are similar for the treatment of ESD-induced ulcers. In large-sized ulcers, esomeprazole plus rebamipide promotes ulcer healing.

The incidence of "silent" free air and aspiration pneumonia detected by CT after gastric endoscopic submucosal dissection

BACKGROUND

Although endoscopic submucosal dissection (ESD) is feasible as a treatment for early gastric cancer, it requires great skill to perform and may place patients at increased risk of a number of complications, including perforation and aspiration pneumonia.

OBJECTIVE

To investigate the incidence of "silent" free air without endoscopic perforation and aspiration pneumonia detected by CT after ESD and risk factors for the development of these 2 conditions.

DESIGN

Prospective cohort study.

SETTING

Single academic center.

PATIENTS

This study involved 87 patients with a total of 91 malignancies.

INTERVENTION

All patients underwent chest and abdominal CT and blood biochemistry analysis before and 1 day after ESD.

MAIN OUTCOME MEASUREMENTS

The incidence of silent free air and aspiration pneumonia after ESD and the related risk factors.

RESULTS

Silent free air was identified in 37.3% of patients without perforation. Tumor location (the upper portion of the stomach), the presence of a damaged muscular layer during ESD, and procedure time, but not specimen size, were significantly associated with silent free air (P = .006, P = .04, P = .02, and P = .53, respectively). According to the receiver-operating characteristic analysis, the resulting cutoff value of the procedure time for silent free air was 105 minutes (67.7% sensitivity, 65.4% specificity). Only procedure time (≥ 105 minutes) was an independent predictor of silent free air development (odds ratio 3.23; 95% confidence interval, 1.21-8.64; P = .02). On the other hand, aspiration pneumonia was seen in 6.6% of patients. Silent free air and aspiration pneumonia did not affect hospitalization.

LIMITATIONS

Single center and small number of patients.

CONCLUSIONS

Silent free air is frequently observed after ESD, and longer procedure time (≥ 105 minutes) was an independent risk factor for silent free air. However, silent free air and aspiration pneumonia detected by CT are not associated with clinically significant complications.

The clinical accuracy of endoscopic ultrasonography and white light imaging in gastric endoscopic submucosal dissection

Purpose

Gastric mucosal neoplastic lesions should have characteristic endoscopic features for successful endoscopic submucosal dissection.

Materials and Methods

Out of the 1,010 endoscopic submucosal dissection, we enrolled 62 patients that had the procedure cancelled. Retrospectively, whether the reasons for cancelling the endoscopic submucosal dissection were consistent with the indications for an endoscopic submucosal dissection were assessed by analyzing the clinical outcomes of the patients that had the surgery.

Results

The cases were divided into two groups; the under-diagnosed group (30 cases; unable to perform an endoscopic submucosal dissection) and the over-diagnosed group (32 cases; unnecessary to perform an endoscopic submucosal dissection), according to the second endoscopic findings, compared with the index conventional white light image. There were six cases in the under-diagnosed group with advanced gastric cancer on the second conventional white light image endoscopy, 17 cases with submucosal invasion on endoscopic ultrasonography findings, 5 cases with a size greater than 3 cm and ulcer, 1 case with diffuse infiltrative endoscopic features, and 1 case with lymph node involvement on computed tomography. A total of 25 patients underwent a gastrectomy to remove a gastric adenocarcinoma. The overall accuracy of the decision to cancel the endoscopic submucosal dissection was 40% (10/25) in the subgroup that had the surgery.

Conclusions

The accuracy of the decision to cancel the endoscopic submucosal dissection, after conventional white light image and endoscopic ultrasonography, was low in this study. Other diagnostic options are needed to arrive at an accurate decision on whether to perform a gastric endoscopic submucosal dissection.

[Clinicopathologic features of cases with negative pathologic results after endoscopic submucosal dissection]

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD) is accepted as a standard treatment of early gastric cancer (EGC) and gastric adenoma. Occasionally, tumorous lesion is not found and pathologic discrepancies can occur after ESD. The aim of this study was to analyze the factors affecting the negative pathologic results after ESD.

METHODS

We retrospectively reviewed the data from all patients with gastric neoplasm (276 EGC and 516 gastric adenomas) who were treated with ESD during past 3 years and enrolled the patients who had negative pathologic results.

RESULTS

Out of 792 patients treated with ESD, 27 patients (3.4%) were eligible for inclusion. Among the 27 patients, factors affecting the negative pathologic results were, most commonly, the focal lesion (n=13, 48.2%) which was small enough to be removed completely during pre-ESD biopsy, followed by pathologic discrepancies (n=11, 40.7%) between pathologists and lastly the operator factor (n=3, 11.1%) dissecting incorrect lesions. Of the focal lesions, the initial pathologic diagnoses were adenocarcinoma in 11 cases (84.6%). In cases with pathologic discrepancies, all the pretreatment diagnoses were adenoma with low grade dysplasia. In cases caused by operator factors, intestinal metaplasia was accompanied by elevated adenoma in all cases.

CONCLUSIONS

To decrease negative pathologic results after ESD, an endoscopist should perform ESD after sufficient communication with pathologists, especially for adenoma with low grade dysplasia, and choose correct lesion, especially located at the antrum and associated with intestinal metaplasia. The possibility of total removal of small lesions even by forcep biopsy should be considered.

Risk factors for perforations associated with endoscopic submucosal dissection in gastric lesions: emphasis on perforation type

BACKGROUND

Endoscopic submucosal dissection (ESD) enables en bloc resection of larger gastric neoplasms. However, the procedure is associated with a high incidence of perforation. Perforations during ESD are divided into macro- and microperforations. Although both types of perforations could cause widespread tissue injury and secondary sepsis, very little is known concerning the risk factors for perforations according to the type of perforation. Thus, this study was performed to evaluate the risk factors for macro-, micro-, and all perforations (both) during ESD.

METHODS

823 gastric lesions (gastric adenoma or early gastric cancer) in 729 patients treated by ESD were enrolled, and their records were reviewed retrospectively. Risk factors were evaluated, focusing on age, sex, gastric neoplasm-related factors (12 locations, resected size, gross type of lesions, presence of ulceration, presence of fibrosis, pathologic diagnosis, and depth of invasion), and ESD procedure-related factors (type of knife, immediate bleeding during ESD, en bloc resection, procedure time, and the number of ESD cases experienced by the endoscopist).

RESULTS

Of the 823 gastric lesions, the rates of all perforation, macroperforation, and microperforation were 9.6%, 7.5%, and 2.1%, respectively. Risk factors for all perforations on multivariate analysis were location of tumor in upper portion, presence of fibrosis, and long procedure time (>2 h). Risk factors for macroperforations were the same as all perforations. Risk factors for microperforations on multivariate analysis were old age (≥81 years), depth of invasion (muscularis mucosa), and long procedure time (>2 h).

CONCLUSIONS

The risk factors for perforations during ESD could differ according to the type of perforation. Therefore, although macroperforation did not develop during ESD, it would be necessary to consider the possibility of microperforation in case of old age, long procedure time, and (deep) depth of invasion.

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.

Clinical features and predictive factors of coagulation syndrome after endoscopic submucosal dissection for early gastric neoplasm

BACKGROUND

Various endoscopic submucosal dissection (ESD)-related complications, such as perforation or bleeding, occur frequently. However, the clinical course of coagulation syndrome (CS) after ESD is not known. The aim of this study was to clarify the clinical outcomes and predictive factors of CS after ESD for early gastric lesions.

METHODS

ESD procedures were performed in the typical sequence (marking, incision, and submucosal dissection). Four hundred and ninety-five patients with early gastric neoplasms were classified into two groups based on their clinical course after ESD: one group with post-ESD CS and the other with a normal clinical course. The clinical outcomes of the CS group were analyzed, and various clinical and pathological factors related to post-ESD CS were investigated using univariate and multivariate analyses.

RESULTS

Coagulation syndrome occurred after ESD in 35 patients. In the CS group, the median period of inflammatory symptoms was 23.7 ± 12.0 h, and no blood cultures showed bacteremia. Multivariate analysis demonstrated that a tumor size of more than 1.5 cm [odds ratio (OR) 5.99, P < 0.001], tumor location in the middle third of the stomach (OR 2.84, P = 0.005), and a procedural time longer than 45 min (OR 2.71, P = 0.033) were independent risk factors for this complication. All patients with CS presented with a favorable outcome, irrespective of antibiotic treatment.

CONCLUSIONS

This study suggests that CS occurs with an incidence of 7.1% after ESD for gastric lesions, and the factors associated with post-ESD CS include tumor size and location, and procedural duration.

Clinical risk factors for perforation during endoscopic submucosal dissection (ESD) for large-sized, nonpedunculated colorectal tumors

BACKGROUND

The possible risk of colonic perforation during endoscopic submucosal dissection (ESD) for colorectal tumors is a barrier to wide application. This retrospective study was performed to evaluate the risk and the predictive factors for perforation during ESD procedure.

METHODS

Between October 2006 and November 2010, a total of 499 consecutive patients (mean age 60.0 ± 11.3 years) who underwent ESD for large-sized (≥ 20 mm), nonpedunculated colorectal tumor were analyzed. First, incidence rate and clinical course of perforation were evaluated. Second, patient-related variables (age, sex, history of aspirin or antiplatelet agents, and comorbidity), endoscopic variables (tumor size, location, and type), procedure-related variables (experience of procedures, procedure time, and materials of submucosal injection), and pathologic diagnosis were analyzed.

RESULTS

The mean size of the lesions was 28.9 mm. The overall en bloc resection rate was 95.0%. Perforation occurred in 37 out of 499 patients (7.4%). Thirty-four patients could be successfully treated conservatively. The type (laterally spreading tumor) and the location (right-sided colon) of the tumors, less experience of the procedure (<100 cases) in each endoscopist, and submucosal injection without hyaluronic acid were associated with higher frequency of perforation (all P < 0.05). On multivariate analysis, laterally spreading type of tumor [odds ratio (OR) 4.10, 95% confidence interval (CI) 1.17-14.34] and submucosal injection with hyaluronic acid (OR 0.31, 95% CI 0.13-0.72) were independent predictive factors.

CONCLUSIONS

Perforation rate was 7.4%, and most cases could be successfully managed nonsurgically. In case of laterally spreading type of tumor, more caution is needed during submucosal dissection and long-lasting submucosal cushion is important for preventing perforation.

Gastric endoscopic submucosal dissection assisted by a new traction method: the clip-band technique. A feasibility study in a porcine model (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) is the standard of care for treating gastric intramucosal neoplasias in Japan. However, it is seldom performed in Western countries, mainly because it is technically very challenging. Several traction methods have been proposed to facilitate submucosal dissection, but they are usually not widely available or are difficult to apply.

OBJECTIVE

Our main aim was to evaluate the feasibility of a new method, the clip-band technique, for improving the visualization of the submucosal layer during ESD.

DESIGN

Observational, experimental, feasibility study conducted in a porcine model.

SETTING

University Hospital of the Canary Islands, Research Animal Laboratory.

PATIENTS

Animal study.

INTERVENTIONS

After completion of the circumferential cutting, a clip-band traction system was applied.

MAIN OUTCOME MEASUREMENTS

Efficacy and safety of the clip-band technique.

RESULTS

Eighteen ESDs performed in live domestic pigs were completed without any serious complications. The mean specimen size was 35.38 ± 12.17 mm, the mean cutting time was 13.06 ± 10.52 minutes, and the mean dissection time was 16.67 ± 9.01 minutes.

LIMITATIONS

The clip-band technique was not compared with the standard ESD technique.

CONCLUSIONS

This initial study shows that the clip-band traction technique is feasible and that it permits safe, effective, and relatively inexpensive gastric ESD.

Barrett's: evolving techniques for dysplasia detection and endoscopic resection

Advanced endoscopic imaging techniques have made the early diagnosis of neoplastic lesions in Barrett's esophagus easier. A new chapter in minimal invasive cancer therapy has been opened. Endoscopic treatment of early neoplasia in Barrett's esophagus (high-grade intraepithelial neoplasia and mucosal adenocarcinoma) has become the method of choice in most countries. Long-term results for endoscopic treatment in a large group of patients are now available. These emerging data suggest that endoscopic therapy is safe and highly effective with long-term complete remission rates of more than 94%. All visible lesions should be treated by endoscopic resection for histologic confirmation of the neoplastic lesion rather than by ablative techniques. After successful endoscopic resection of all visible and localizable high-grade intraepithelial neoplasia and mucosal cancer, ablative treatment of the remaining Barrett's epithelium at risk should be performed to reduce the rate of recurrent or metachronous neoplasia.

Endoscopic submucosal dissection for premalignant lesions and noninvasive early gastrointestinal cancers

AIM: To investigate the indication, feasibility, safety, and clinical utility of endoscopic submucosal dissection (ESD) in the management of various gastrointestinal pathologies.

METHODS: The medical records of 60 consecutive patients (34 female, 26 male) who underwent ESD at the gastroenterology department of Kocaeli University from 2006-2010 were examined. Patients selected for ESD had premalignant lesions or non-invasive early cancers of the gastrointestinal tract and had endoscopic and histological diagnoses. Early cancers were considered to be confined to the submucosa, with no lymph node involvement by means of computed tomography and endosonography.

RESULTS: Sixty ESD procedures were performed. The indications were epithelial lesions (n = 39) (33/39 adenoma with high grade dysplasia, 6/39 adenoma with low grade dysplasia), neuroendocrine tumor (n = 7), cancer (n = 7) (5/7 early colorectal cancer, 2/7 early gastric cancer), granular cell tumor (n = 3), gastrointestinal stromal tumor (n = 2), and leiomyoma (n = 2). En bloc and piecemeal resection rates were 91.6% (55/60) and 8.3% (5/60), respectively. Complete and incomplete resection rates were 96.6% (58/60) and 3.3% (2/60), respectively. Complications were major bleeding [n = 3 (5%)] and perforations [n = 5 (8.3%)] (4 colon, 1 stomach). Two patients with colonic perforations and two patients with submucosal lymphatic and microvasculature invasion (1 gastric carcinoid tumor, 1 colonic adenocarcinoma) were referred to surgery. During a mean follow-up of 12 mo, 1 patient with adenoma with high grade dysplasia underwent a second ESD procedure to resect a local recurrence.

CONCLUSION: ESD is a feasible and safe method for treatment of premalignant lesions and early malignant gastrointestinal epithelial and subepithelial lesions. Successful en bloc and complete resection of lesions yield high cure rates with low recurrence.

Short-term outcomes of endoscopic submucosal dissection (ESD) for early gastric neoplasm: multicenter survey by osaka university ESD study group

BACKGROUND

Endoscopic submucosal dissection (ESD) was developed for en bloc removal of large and flat gastrointestinal tract neoplasms. In Japan, ESD is performed under conscious sedation. The risks for sedation-related complications of ESD, such as postoperative pneumonia, have not been evaluated. The aim of this study was to evaluate the incidence of postoperative pneumonia after ESD in a multicenter survey.

PATIENTS AND METHODS

A total of 1188 patients with upper gastric neoplasms treated with ESD in nine hospitals were enrolled from May 2003 to September 2008. The en bloc resection rates and complications (bleeding, perforation, and postoperative pneumonia) were assessed. The correlations between the clinical variables and complications were investigated using logistic regression models.

RESULTS

The en bloc resection rate was 95.3%. Bleeding, perforation, and pneumonia occurred in 37 (3.1%), 49 (4.1%), and 19 (1.6%) patients, respectively. Univariate analysis indicated that procedure time, but not specimen size, or patient age, or sex, was significantly related to bleeding and perforation. The incidence of pneumonia was higher in patients with ulceration, older patients (≥75years), and those with a long procedure duration (≥5h).

CONCLUSION

The incidence of pneumonia, but not perforation and bleeding, after ESD, is high in older patients (≥75years). Special care should be taken with older patients undergoing ESD to minimize the risk of postoperative pneumonia.

Endoscopic submucosal dissection training with pig models in a Western country

AIM: To test a strategy for endoscopic submucosal dissection (ESD) training in animal models designed to overcome the initial learning curve.

METHODS: ESD was attempted in ex vivo and in vivo pig models. Thirty ESD procedures were attempted in the esophagus (n = 9) or the stomach (n = 21). The ex vivo model was used until initial competence was achieved. In the in vivo model, several ESD procedures were performed in up to 3 sessions. The following variables were analyzed: specimen size, complete and en bloc resection rate, time for circumferential incision, time for submucosal dissection, total ESD duration, and complications.

RESULTS: Complete resection was achieved in 28 cases (en bloc 27); 2 could not be completed (one perforation, one technical difficulty). The mean ± SD time for circumferential incision was 36.2 ± 16.8 min (range: 8-87 min), and the mean ± SD time for submucosal dissection was 45.1 ± 35.7 min (range: 9-196 min). The mean ± SD size of the resected specimens was 45.2 ± 17.8 mm. The mean ± SD total resection time was significantly increased for the gastric cases performed in the first half of the study (n = 13) than in the second half (n = 8) (98.9 ± 62.4 min vs 61.7 ± 17.6 min, P = 0.04), although the specimen size did not differ.

CONCLUSION: Training in animal models could help endoscopists overcome the learning curve before starting ESD in humans.

Endoscopic mucosal resection and endoscopic submucosal dissection for early gastric cancer: Current and original devices

Compared with endoscopic submucosal dissection (ESD), endoscopic mucosal resection (EMR) is easier to perform and requires less time for treatment. However, EMR has been replaced by ESD, because achieving en bloc resection of specimens > 20 mm in diameter is difficult with EMR. The technique of ESD was introduced to resect large specimens of early gastric cancer in a single piece. ESD can provide precise histological diagnosis and can also reduce the rate of recurrence, but has a high level of technical difficulty, and is consequently associated with a high rate of complications, a need for advanced endoscopic techniques, and a lengthy procedure time. To overcome disadvantages in both EMR and ESD, various advances have been made in submucosal injections, knives, other accessories, and in electrocoagulation systems.

Therapeutic outcomes in 1000 cases of endoscopic submucosal dissection for early gastric neoplasms: Korean ESD Study Group multicenter study

BACKGROUND

The technique of endoscopic submucosal dissection (ESD) was introduced to be able to obtain en bloc specimens of large early GI neoplasms. The drawback of ESD is its technical difficulty, which, consequently, is associated with a higher rate of complication and which requires advanced endoscopic techniques and a long procedure time.

OBJECTIVE

To assess the therapeutic outcome of ESD by expert endoscopists who have at least 3 years' experience of EMR in Korea.

DESIGN

A retrospective, multicenter study.

PATIENTS

From January 2006 to June 2007, 1000 early gastric cancers in 952 patients (502 men, 450 women; mean age 62.1 years, range 43-90 years) were treated by using ESD at 6 Korean ESD study group (KESG)-related university hospitals in Korea.

INTERVENTION

We performed ESD procedures with typical sequences (marking, incision, and submucosal dissection).

MAIN OUTCOME MEASUREMENTS

The rate of en bloc resection, incidence of complication, and length of procedure. Predetermined factors (various endoscopic and final pathologic features) for these outcomes.

RESULTS

The rates of en bloc resection, complete en bloc resection, vertical incomplete resection, and piecemeal resection were 95.3%, 87.7%, 1.8%, and 4.1%, respectively. The rates of delayed bleeding, significant bleeding, perforation, and surgery related to complication were 15.6%, 0.6%, 1.2%, and 0.2%, respectively. The mean procedure time was 47.8 +/- 38.3 minutes. The rates of en bloc resection differed significantly in relation to the location of the lesions (upper portion vs middle portion vs lower portion of the stomach, 88.6% vs 95.2% vs 96.0%, respectively; P = .02), presence of a scar (no vs yes, 96.0% vs 89.5%, respectively; P = .002), and histologic type (low-grade adenoma vs high-grade adenoma vs differentiated early gastric cancer vs undifferentiated early gastric cancer, 95.8% vs 94.6% vs 96.2% vs 83.8%, respectively; P = .007). The rates of delayed bleeding differed significantly in relation to location (upper portion vs lower portion of the stomach, 28.6% vs 13.8%, respectively; P = .003), the size of the tumor (>40 mm vs <20 mm, 28.6% vs 13.7%, respectively; P = .009), recurrent lesion (29.4% vs 15.1%, respectively; P = .024), and macroscopic type (flat vs elevated, 18.8% vs 12.4%, respectively; P = .047). Factors related to the longer procedure time were location (upper portion vs lower portion of the stomach, 64.8 vs 44.1 minutes, respectively; P < .001), the size of the tumor (>40 mm vs < 20 mm, 67.1 vs 42.0 minutes, respectively; P < .001), the presence of ulcer (54.6 vs 46.8 minutes; P < .045), and the presence of a scar (69.2 vs 45.0 minutes; P < .001).

CONCLUSIONS

ESD is an effective and safe therapy in the management of early gastric neoplasms. Endoscopists have to accept the need for advanced endoscopic techniques for performing ESD in the case of large lesions, scar lesions, undifferentiated cancers, or for the lesions in the upper portion of the stomach. Endoscopists require more experience to decrease complications in patients who have a large or recurrent lesion in the upper portion of the stomach; these lesions also take more time to complete the ESD procedure.

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.

Endoscopic submucosal dissection of early cancers, flat adenomas, and submucosal tumors in the gastrointestinal tract

BACKGROUND & AIMS

Endoscopic submucosal dissection (ESD) is a promising technique in the treatment of large premalignant and early malignant gastrointestinal lesions. In contrast to Japan and Asian countries, few data are available from Western countries. The objective of this study was to assess the feasibility of ESD in a European center, with special regard for the success rate and learning curve.

METHODS

Over a 4-year-period, 82 epithelial or submucosal lesions were referred for ESD. Seventy-one ESDs were performed (51 gastric, 17 rectal, 2 esophageal, and 1 duodenal). Resection rates, procedure times, specimen sizes, complications, and recurrences were noted. The mean follow-up period was 15 months.

RESULTS

Specimen size increased significantly (P < .05) and procedural duration decreased significantly (P < .005) over time. En bloc resection rates and R0 en bloc resection rates were 77.1% and 65.7%, respectively, in the first half of the study and increased to 86.1% and 72.2%, respectively, in the second half (P = NS). No recurrence was observed after R0 en bloc resection whereas the recurrence rate was 38.5% after piecemeal resections (P < .001). Two perforations in the first series were treated by surgery; 2 other perforations, 8 minor bleedings, and 2 pyloric stenoses were treated endoscopically.

CONCLUSIONS

ESD is technically feasible and shows promising results in this German single-center-study. ESD is time consuming and difficult but shows a learning curve resulting in a decrease of the procedural duration over time. R0 en bloc resection is mostly possible and can avoid the risk of local recurrence.

Chromoendoscopy with indigo carmine dye added to acetic acid in the diagnosis of gastric neoplasia: a prospective comparative study

BACKGROUND

Conventional endoscopy and chromoendoscopy with indigo carmine dye are usually performed for recognizing adequate tumor-negative lateral margins for successful endoscopic resection of gastric neoplasia. However, chromoendoscopy with indigo carmine dye added to acetic acid has not been used for this purpose.

OBJECTIVE

Our purpose was to compare the diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid with that of conventional endoscopy and chromoendoscopy with indigo carmine dye or acetic acid alone.

DESIGN

Prospective study.

SETTING

Social Insurance Funabashi Central Hospital.

PATIENTS

Forty-seven consecutive patients (53 lesions) with early gastric cancer and gastric adenomas who underwent endoscopic submucosal dissection (ESD) from April 2006 to July 2007 were studied.

INTERVENTIONS

All the lesions were examined by the endoscopic modalities before ESD, and the resected specimens were analyzed histopathologically.

MAIN OUTCOME MEASUREMENTS

Two endoscopists independently evaluated the diagnostic performance of each image in terms of recognition of tumor borders with reference to macroscopic and histopathologic findings of resected specimens. We also conducted a substudy to assess interobserver variability.

RESULTS

There was good interobserver agreement between the 2 endoscopists in this study (kappa index = 0.764). The diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid was significantly greater than that of any of the other modalities (vs each: P < .005).

CONCLUSIONS

The diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid was better compared with conventional endoscopy and chromoendoscopy by using only indigo carmine dye or acetic acid. The applicability of this method for gastric neoplasia merits further investigation.

Percutaneously assisted endoscopic surgery using a new PEG-minitrocar for advanced endoscopic submucosal dissection (with videos)

BACKGROUND

For endoscopic submucosal dissection (ESD), adequate exposure and visualization of the submucosa for controlled dissection is of eminent importance.

OBJECTIVE

To determine the feasibility and safety of percutaneously assisted endoscopic surgery (PA-ES) with a new prototype PEG-minitrocar (PMT) for advanced ESD in a porcine model.

INTERVENTIONS

Placement of the PMT was done in all pigs by the use of a modified pull-through technique. After endoscopic incision of the mucosa, traction was provided for ESD by grasping the incisional margins of the mucosa with a rigid forceps introduced through the PMT, enabling stepwise dissection of the exposed submucosa under direct vision.

MAIN OUTCOME MEASUREMENTS

Feasibility and safety of the new PMT for PA-ES and en bloc resection of prespecified mucosal areas.

RESULTS

The study started with acute experiments in 8 animals, followed by a 10-day survival study in another 8 pigs. A total of 20 mucosal pieces were resected. The sizes of the resected pieces varied up to 7.5 x 4.0 cm ex vivo. All but one could be resected en bloc. Percutaneous assistance resulted in an excellent exposure of the submucosal space and enabled stepwise dissection of the submucosal connective tissue. Neither the PMT nor advanced ESD led to relevant complications.

CONCLUSIONS

We demonstrated the feasibility and safety of a new PMT for advanced ESD. With the use of PA-ES, mucosal pieces of various sizes can be resected en bloc in gastric locations that are difficult to access by flexible endoscopy alone.

EMR for early gastric cancer in Korea: a multicenter retrospective study

BACKGROUND

EMR has been accepted as a treatment modality for selected cases of early gastric cancer (EGC) in Japan. However, long-term outcomes after EMR for EGC have not been fully documented.

OBJECTIVES

We reviewed the experiences of EMR for EGC in Korea, with emphasis on the long-term outcome.

DESIGN

Multicenter, retrospective study.

METHODS

Data were collected retrospectively by use of the on-line database registry system. From January 2000 to December 2002, 514 EGCs in 506 patients were treated by EMR in 13 institutions in Korea. Median age of the patients was 60 years (range 45-83 years). The resection was regarded as incomplete if histopathologic examination revealed a positive resection margin or submucosal invasion or positive lymphovascular invasion or undifferentiated histologic diagnosis.

RESULTS

The most commonly used technique was circumferential precutting followed by snare resection (EMR-P, n = 269, 52.3%). Complete resection and incomplete resection after EMR were confirmed in 399 lesions (77.6%) and 103 lesions (20.0%), respectively. For completely resected mucosal cancers (n = 399), the median duration of follow-up was 23.5 months (range 5-70 months). In this group, local recurrence was detected in 24 cases (6.0%) with a median interval between EMR and recurrence of 17.9 months (range 3.5-51.7 months). There were 3 cases with perforation and 71 cases with bleeding. No deaths were related to recurrence of gastric cancer during the overall median follow-up period of 39 months.

LIMITATIONS

Multicenter retrospective design, no controls.

CONCLUSIONS

EMR is an effective therapeutic modality for selected cases of EGC in Korea.

Insulated-tip knife endoscopic mucosal resection of large colorectal polyps unsuitable for standard polypectomy

OBJECTIVES

Endoscopic mucosal resection (EMR) has been shown to be safe and effective. En bloc resection is often not achieved using conventional EMR. Insulated-tip knife (It-knife) EMR has been recently proposed for early gastric cancer dissection and removal. This study was conducted to evaluate the safety and efficacy in obtaining en bloc resection with It-knife EMR of large colonic lesions not resectable with standard endoscopic techniques.

METHODS

A total of 29 patients (19 men, 10 women, mean age 67.5 yr, range 44-88) were included in the study. Lesions were considered not suitable for standard polypectomy because of large diameter (>3 cm), morphology, and/or position. Lesions were located in the rectum (N = 11), sigmoid: (N = 10), descending: (N = 4), transverse: (N = 2), and hepatic flexure (N = 2). After saline injection, circumferential incision and dissection of the lesions were attempted with the aim of achieving en bloc resection.

RESULTS

En bloc resection was achieved in only 55.1% of the lesions (16 out of 29 patients). In the remaining cases, resection was completed with a piecemeal technique. The median size of the en bloc resected specimen was 3 x 3.4 cm. Complications occurred in four patients (13.7%). At histopathology, 13 patients had low-grade dysplasia, 15 high-grade dysplasia. One patient had a tumor invading the submucosa and was submitted to surgery.

CONCLUSIONS

It-knife EMR is a promising technique for attempting en bloc resection of large colonic polyps. Adequate training and caution are required because it can be associated with a higher complication rate than with other EMR modalities.

State of the art on endoscopic mucosal resection and endoscopic submucosal dissection

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) provide new alternatives for minimally invasive treatment of superficial gastrointestinal malignancies. Evidence suggests that these techniques can be performed safely and have comparable outcomes to surgery with less morbidity and better quality of life due to their tissue-sparing nature when compared with conventional surgery. Although the techniques and accessories have become standardized, there is room for improvement, and further research and development are required. Current challenges facing American gastroenterologists or endoscopic surgeons include access to training and lack of appropriate reimbursement for these heavy-weighted and technically demanding procedures. Nevertheless, EMR and ESD are here to stay and are only the first steps toward true radical endoluminal resection of GI malignancies.

Endoscopic submucosal dissection for colorectal neoplasia: possibility of standardization

BACKGROUND

Endoscopic submucosal dissection (ESD) has been positively applied to and gradually standardized for early stomach cancer, particularly in Japan. However, because it is technically difficult to perform ESD of the colon, ESD is not a commonly used technique.

OBJECTIVE

The aim of this study was to evaluate the possibility of standardizing colorectal ESD.

SETTING

ESD was performed at the Department of Endoscopy, Hiroshima University Hospital.

DESIGN

Time required for ESD, rate of complete en bloc resection, complication, and postoperative local persistence and recurrence were investigated retrospectively in 70 cases of colorectal neoplasia, wherein the lesion was more than 20 mm in diameter.

INTERVENTIONS

All lesions were resected by ESD.

RESULTS

The average (+/-SD) time required for ESD was 70.5+/-45.9 minutes (range, 15-180 minutes), and the histologic rate of complete en bloc resection was 80.0% (56/70). With regard to complication, 1.4% of cases of postoperative hemorrhage (1/70) and 10.0% of cases of perforation (7/70) were observed in total. The rate of perforation was investigated with respect to the type of knife used for ESD and the period after the induction of ESD. The rate of perforation markedly decreased with the practice of the technique. Moreover, the rate of perforation was high when an insulated-tip diathermic knife was used; practicing this technique was insufficient to reduce the rate of perforation. The average duration of follow-up was 614+/-289.5 days, and no case of local persistence and recurrence or metastasis was observed.

LIMITATIONS

The ESD technique depends on the level of each skill of each colonoscopist.

CONCLUSIONS

With regard to ESD of the colon, complication, eg, perforation, could be decreased by sufficient practice and selection of an appropriate knife. It is suggested that, in the near future, ESD will be standardized for the colon.

Analysis of endoscopic electronic image of intramucosal gastric carcinoma using a software program for calculating hemoglobin index

Hemoglobin is the predominent pigment in the gastrointestinal mucosa, and the development of electronic endoscopy has made it possible to quantitatively measure the mucosal hemoglobin volume, by using a hemoglobin index (IHb). The aims of this study were to make a software program to calculate the IHb and then to investigate whether the mucosal IHb determined from the electronic endoscopic data is a useful marker for evaluating the color of intramucosal gastric carcinoma with regard to its value for discriminating between the histologic types. We made a software program for calculating the IHb in the endoscopic images. By using this program, the mean values of the IHb for the carcinoma (IHb-C) and those of the IHb for the surrounding non-cancerous mucosa (IHb-N) were calculated in 75 intestinal-type and 34 diffuse-type intramucosal gastric carcinomas. We then analyzed the ratio of the IHb-C to the IHb-N (C/N ratio). The C/N ratio in the intestinal-type carcinoma group was higher than that in the diffuse-type carcinoma group (p<0.001). In the diffuse-type carcinoma group, the C/N ratio in the body was lower than that in the antrum (p=0.022). The accuracy rate, sensitivity, specificity, and the positive and negative predictive values for the differential diagnosis of the diffuse-type carcinoma from the intestinal-type carcinoma were 94.5%, 94.1%, 94.7%, 88.9% and 97.3%, respectively. IHb is useful for making quantitative measurement of the endoscopic color in the intramucosal gastric carcinoma, and the C/N ratio by using the IHb would be helpful for distinguishing the diffuse-type carcinoma from the intestinal-type carcinoma.

Clinical outcomes of EMR for gastric tumors: historical pilot evaluation between endoscopic submucosal dissection and conventional mucosal resection

BACKGROUND

EMR is currently a standard treatment for mucosal gastric tumors. Endoscopic submucosal dissection (ESD) has been developed for en bloc resection.

OBJECTIVE

We evaluated the clinical outcomes of ESD compared with conventional EMR.

DESIGN

Not applicable.

SETTING

A historical control study was performed between EMR and ESD.

PATIENTS

EMR of 245 gastric tumors was performed in 229 patients. Lesions were divided into two groups. Conventional EMR was performed in group A from February 1999 to June 2001, and ESD was performed in group B from July 2001 to March 2004. Group B was divided into subgroups: subgroup B-1 underwent ESD from July 2001 to March 2003 and subgroup B-2 from April 2003 to March 2004.

INTERVENTIONS

All lesions were resected with conventional EMR or with ESD.

MAIN OUTCOME MEASUREMENTS

En bloc resection rate, rate in completeness of resection, required time, remnant ratio, and complications were evaluated.

RESULTS

With regard to lesions >10 mm in size, the en bloc resection rate and the rate in completeness of resection of group B was significantly higher than that of group A (p < 0.01). Although the required time was longer in group B than A (p < 0.01), it was shorter in subgroup B-2 compared with B-1 (p < 0.05) with lesions < or =10 mm in size. The remnant ratio and perforation rate were not different between groups.

LIMITATIONS

Not applicable.

CONCLUSIONS

The en bloc resection rate was better with ESD than with conventional EMR. The required time was longer in ESD, but this disadvantage might be improved with experience.

Symptoms and diagnosis of gastric cancer at early curable stage

Five-year survival of gastric cancer is 10% in Western countries compared with over 50% in Japan. This is because the disease is not identified in the West until later in its evolution. T1 cancer has an excellent prognosis, but most of the patients either have no symptoms or complain of long-standing, non-specific dyspepsia; alarm symptoms, when identified, usually indicate that the cancer is already inoperable. Early gastric cancer is infrequently diagnosed in the West because the low prevalence of gastric cancer means that endoscopists do not search with the same diligence as they do in Japan. A further barrier is the widespread prescription of proton pump inhibitors that heal malignant ulcers and diminish symptoms, thus rendering them more difficult to identify clinically and endoscopically. An improvement in diagnosis may be achieved by newer endoscopy technology which enables cancers to be identified more easily, or by an inexpensive screening test to select patients with extensive gastric atrophy, thereby identifying those at risk who can then be screened endoscopically.