Esophageal Esophageal Endoscopic Submucosal Dissection Research Articles

Predictors of technical difficulty for trainees in esophageal endoscopic submucosal dissection.

Esophageal endoscopic submucosal dissection (ESD) is technically challenging, especially for trainees, and requires a safe training system. This study aimed to identify predictors of technical difficulty facing trainees performing esophageal ESD to establish such system. This was a single-center retrospective study of patients with esophageal cancer who underwent ESD performed by trainees between January 2010 and August 2022. Technical difficulties were defined as muscularis propria exposure and long procedure time (≥ 90min). Factors associated with these technical difficulties were investigated. A total of 798 lesions in 721 patients were evaluated. Muscularis propria exposure occurred in 298 lesions (37.3%), including 10 perforations (1.3%). The procedure time was ≥ 90min in 134 lesions (16.8%). In the multivariate analysis, tumor size ≥ 20mm, tumors ≥ 1/2 of the circumference, and those close to previous treatment scars significantly increased the incidence of both difficulties, whereas tumors in the upper esophagus significantly decreased this incidence. Furthermore, female sex and tumors in the left wall were independent predictors of muscularis propria exposure, and elevated morphology was an independent predictor of long procedure time. Muscularis propria exposure and long procedure time occurred in more than half of the cases with three or more predictors of each difficulty. Large tumors and tumors close to previous treatment scars increase technical difficulties for trainees in esophageal ESD. Conversely, tumors in the upper esophagus reduce these difficulties. These results enable us to predict the difficulty level preoperatively and select appropriate cases in stepwise training.

A stag beetle knife can achieve stabler and safer endoscopic submucosal dissection in the esophagus

Abstract Background and study aims Esophageal endoscopic submucosal dissection (ESD) has a higher complication rate than gastric ESD. Scissor-type devices, including the stag beetle (SB) knife, are reportedly safer and have shorter procedure times than tip devices. To clarify the characteristics of the SB knife, we compared the treatment outcomes of esophageal ESD with a tip-type knife to those with an SB knife combination. Patients and methods Between January 2016 and March 2023, clinical data from 197 lesions in 178 patients who underwent esophageal ESD were analyzed retrospectively. Every lesion was assigned to either the tip-type group or the SB group based on the devices with which the submucosa was initially dissected. We compared procedure time and complications and analyzed the risk of muscular exposure using multivariate analysis. Results Procedure time was not significantly different between the tip-type and SB groups (60.3±42.2 min vs. 58.8±29.1 min). The variation in procedure time was significant according to F test P=0.002). Incidence of muscular exposure was significantly lower in the SB group than in the tip-type group (24.5% vs. 11.1%, P=0.016). These differences were significant in resected specimens larger than 21 mm. Procedure time over 60 minutes (odds ratio [OR] 2.5, 95% confidence interval [CI]: 1.15–5.42, P=0.02) was a risk factor for muscular exposure, and submucosal dissection with an SB knife was a safety factor (OR 0.4, 95% CI: 0.18–0.89, P=0.02). Conclusions Performing esophageal ESD with an SB knife is a safe procedure with less variation in procedure time and less muscule exposure.

Outcomes of endoscopic submucosal dissection for esophageal cancer with segmental absence of intestinal musculature

Perforation during esophageal endoscopic submucosal dissection (ESD) typically results from electrical damage. However, there are cases in which perforation occurs because of segmental absence of intestinal musculature (SAIM) without iatrogenic muscular injury. We investigated the occurrence rate and clinical course of SAIM during esophageal ESD. We conducted a retrospective review of esophageal ESDs performed between 2013 and 2019 at 10 centers in Japan. Five of 1708 (0.29%) patients received ESD for esophageal cancer and had SAIM. The median muscular defect size was 20mm. All lesions were resected without discontinuation. After resection, 3 patients were closed with Endoloop. Four patients had mediastinal emphysema. All patients were managed conservatively. SAIM is a very rare condition that is usually only diagnosed during ESD. Physicians performing esophageal ESD should be aware of SAIM. When SAIM is detected, the ESD technique should be modified to prevent full-thickness perforation.

Repeated steroid injection and polyglycolic acid shielding for prevention of refractory esophageal stricture

BackgroundPostoperative stricture and refractory stricture are severe adverse events which occur after expansive esophageal endoscopic submucosal dissection (ESD). The aim of this study was to assess the efficacy of steroid injection, polyglycolic acid (PGA) shielding, and of additional steroid injection thereafter for the prevention of refractory esophageal stricture.MethodsThis is a retrospective cohort study of 816 consecutive cases of esophageal ESD performed between 2002 and 2021 at the University of Tokyo Hospital. After 2013, all patients with a diagnosis of superficial esophageal carcinoma covering over 1/2 the esophageal circumference underwent preventive treatment immediately after ESD with either “PGA shielding”, “steroid injection”, or “steroid injection + PGA shielding”. Additional steroid injection was performed for high-risk patients after 2019.ResultsThe risk of refractory stricture was especially high in the cervical esophagus (OR 24.77, p = 0.002) and after total circumferential resection (OR 894.04, p < 0.001). “Steroid injection + PGA shielding” was the only method significantly effective in preventing stricture occurrence (OR 0.36; 95% CI 0.15–0.83, p = 0.012). This method also decreased the risk of refractory stricture (OR 0.38; 95% CI 0.10–1.28, p = 0.096), but additional steroid injection was the only significantly effective method for prevention of refractory stricture (OR 0.42; 95% CI 0.14–0.98, p = 0.029).ConclusionCombining steroid injection and PGA shielding is effective for preventing post-ESD stricture and refractory stricture. Additional steroid injection is a viable option for patients at high-risk for refractory stricture.Graphical abstract

First clinical experience with esophageal ESD using a novel adjustable traction device.

Background and study aims In esophageal endoscopic submucosal dissection (ESD), the effectiveness of traction including clip-thread method has been reported, but it is difficult to adjust the direction of traction. Therefore, we developed a dedicated over-tube type traction device (ENDOTORNADO) that has a working channel and allows traction from any directions by rotating itself. We investigated the clinical feasibility and potential usefulness of this new device in esophageal ESD. Patients and methods This was a single-center, retrospective study. Six cases of esophageal ESD with ENDOTORNADO from January to March 2022 (tESD group) were compared with 23 cases of conventional esophageal ESD performed by the same operator from January 2019 to December 2021 (cESD group) in terms of clinical treatment outcomes. Results In all cases, en bloc resection was achieved without intraoperative perforation. The total procedure speed was significantly increased in tESD group (23 vs. 30 mm 2 /min, P = 0.046). In particular, the submucosal dissection time was significantly reduced to about one-quarter in tESD group (11 vs. 42 min, P = 0.004). Conclusions ENDOTORNADO creates the adjustable traction from any directions and may have the clinical feasibility. It would be an option for human esophageal ESD.

Prophylactic use of steroids for a mucosal defect with a circumference of less than three-fourths prevents both symptomatic and asymptomatic stricture after esophageal endoscopic submucosal dissection.

Subclinical stricture after esophageal endoscopic submucosal dissection (ESD) makes the detection and re-ESD of metachronous lesions difficult. This study aimed to investigate the effectiveness of prophylactic steroid use after esophageal ESD for mucosal defects with a circumference less than 75% for the prevention of symptomatic and asymptomatic stricture. In 80 retrospectively enrolled patients, we collected paired endoscopic images of a mucosal defects immediately after resection and a scar thereafter. After calculating circumference by image analysis software, all patients were classified into three groups in reference to mucosal defect circumference (MDC; ≤ 50%, 50-75%, ≥ 75%). Frequency of steroid use and symptomatic stricture were compared, and in < 75% MDC patients, a degree of asymptomatic stricture with or without steroid was compared by calculating a scar contraction rate (SCR). In the ≤ 50% (43 patients), 50-75% (27 patients) and ≥ 75% (10 patients) MDC groups, steroids were used in 12%, 59% and 100%, respectively, and symptomatic stricture occurred in 0%, 7% and 40%, respectively. In < 75% MDC patients, SCR in the steroid cohort was significantly lower than that in the nonsteroid cohort (42% vs. 65%, p = 0.002). No steroid-related adverse events occurred. Steroid use even for mucosal defects with < 75% circumference appears effective for the reduction of the risk on both symptomatic and asymptomatic stricture after esophageal ESD.

The relationship between the esophageal endoscopic submucosal dissection technical difficulty and its intraoperative process.

Estimating the esophageal endoscopic submucosal dissection (ESD) technical difficulty is important to reduce complications. Endoscopic duration is one of the related factors to a technical difficulty. The relationship between the esophageal ESD technical difficulty and its intraoperative process was analyzed as a first step toward automatic technical difficulty recognition using artificial intelligence. This study enrolled 75 patients with superficial esophageal cancer who underwent esophageal ESD. The technical difficulty score was established, which consisted of three factors, including total procedure duration, en bloc resection, and complications. Additionally, technical difficulty-related factors, which were perioperative factors that included the intraoperative process, were investigated. Eight (11%) patients were allocated to high difficulty, whereas 67 patients (89%) were allocated to low difficulty. The intraoperative process, which was shown as the extension of each endoscopic phase, was significantly related to a technical difficulty. The area under the curve (AUC) values were higher at all the phase duration than at the clinical characteristics. Submucosal dissection phase (AUC 0.902; 95% confidence intervals (CI) 0.752-1.000), marking phase (AUC 0.827; 95% CI 0.703-0.951), and early phase which was defined as the duration from the start of marking to the end of submucosal injection (AUC 0.847; 95% CI 0.701-0.992) were significantly related to technical difficulty. The intraoperative process, particularly early phase, was strongly associated with esophageal ESD technical difficulty. This study demonstrated the potential for automatic evaluation of esophageal ESD technical difficulty when combined with an AI-based automatic phase evaluation system.

Influence of Esophageal Endoscopic Submucosal Dissection on the Changes of Energy Metabolism during the Perioperative Period.

Simple SummaryThis study aimed to measure resting energy expenditure (REE) and assess the physical invasiveness of esophageal endoscopic submucosal dissection (ESD) during perioperative periods. In addition, the factors affecting changes in REE were investigated. Subjects were examined using an indirect calorimeter and the stress factor was calculated based on basal energy expenditure and body weight. REE/body weight on the day following ESD was significantly higher than that of the same day. The stress factor on the day after ESD was 1.11. The increase in WBC, neutrophil, and CRP levels was associated with the change in REE ratio. Among the factors affecting changes in energy metabolism, only the total resection area was associated with changes in REE. It is suggested that patients who undergo esophageal ESD require more attention in perioperative management when the resection area of the lesions is larger.Esophageal endoscopic submucosal dissection (ESD) is considered to be more complex than gastric ESD. This study aimed to assess the physical invasiveness of esophageal ESD during perioperative periods by measuring resting energy expenditure (REE). The factors affecting REE that could be used to identify patients requiring perioperative management were also investigated. Overall, 75 patients who had undergone esophageal ESD were prospectively enrolled. REE, body weight, and basal energy expenditure were measured on the day of and the day following ESD. The mean REE/body weight was 20.2 kcal/kg/day on the day of ESD and significantly increased to 23.0 kcal/kg/day one day after ESD. The stress factor on the day after ESD was 1.11. White blood cell, neutrophil, and C-reactive protein levels increased on the day after ESD and correlated with the changes in REE. Among the factors including age, body mass index, total resection area, operation time, and sarcopenia, only the total resection area was associated with changes in REE. In conclusion, energy metabolism increases during the perioperative period for esophageal ESD. The increase in the stress factor for esophageal ESD was higher than that in gastric and colorectal ESD. Furthermore, patients with large resection areas require greater attention in perioperative management.

Randomized study of two endo-knives for the traction-assisted endoscopic submucosal dissection of early esophageal squamous cell carcinoma

Needle-type devices, such as the DualKnife (Olympus, Tokyo, Japan), are widely used for traction-assisted esophageal endoscopic submucosal dissection (ESD) but require a prolonged operation time. An improved model of the ITknife (Olympus), the ITknife nano, may allow faster and easier ESD than the DualKnife. We conducted a randomized study to compare the performances of the DualKnife and the ITknife nano for traction-assisted esophageal ESD. Patients with early esophageal squamous cell carcinoma were eligible for this study. The primary outcome was the total procedure time. The secondary outcomes were submucosal dissection time, en bloc, and complete resection rates, perforation rate, and adverse events. Results Fifty patients were equally divided into two groups: the DualKnife group (D-group) and the ITknife nano group (I-group), and all underwent the assigned treatment. The I-group had significantly shorter total procedure time (36.8 vs. 60.7 min; P < 0.01) and submucosal dissection time (17.2 vs. 35.8 min; P < 0.01) than the D-group. The en bloc and complete resection rates were sufficiently high in both groups (100% and 100% in the D-group and 100% and 96% in the I-group, respectively). Significantly fewer hemostatic procedures due to intraoperative bleeding were performed in the I-group than in the D-group (0.2 vs. 1.4; P < 0.01). Delayed bleeding, perforation, or esophageal stricture did not occur in either group. The ITknife nano exhibited lower procedure time for traction-assisted esophageal ESD than the DualKnife, without increasing adverse events.

Translation from manual to automatic endoscopic insufflation enhanced by a pressure limiter.

Optimal visualization and safety have always been essential in performing any type of endoscopic surgery. However, the safety of automatic gastrointestinal (GI) insufflation has yet to be thoroughly studied, especially when combined with manual insufflation. The current study aimed to verify whether the pressure limiter could lower GI endoluminal pressure during endoscopic procedures and affect the behavioral patterns of endoscopists. A preclinical blinded trial was conducted on endoscopists who had no knowledge regarding the presence of the pressure limiter that prevents a GI endoluminal pressure above 25mmHg. Endoscopists in group A performed esophageal endoscopic submucosal dissection (ESD) with our insufflation device equipped with the pressure limiter, whereas those in group B performed the same procedure without the pressure limiter. During all procedures, endoluminal pressure was continuously monitored. The primary endpoint of the current study was to measure the endoluminal pressure with or without the pressure limiter during esophageal ESD, while the secondary endpoint was to evaluate the effect of the pressure limiter on intraesophageal pressure and perioperative outcomes during esophageal ESD. A questionnaire survey was conducted after each session. A total of 79 endoscopists were included in this randomized control study. Group A had significantly lower endoluminal pressure than group B (10.6 ± 4.61 vs. 16.25 ± 7.51mmHg, respectively; p < 0.05). Although two pigs in group B died from tension pneumothorax, none in group A died. Evaluation of lumen expansion, ease of aspiration, and visual field reproducibility were poorer in group A than in group B, although all fell within the acceptable range. Subjective evaluation of usability was divided into two categories, Excellent/Good and Poor/Bad, with no significant differences in any of the items. This preclinical study showed that endoscopic treatment with an automatic insufflation system could be performed at lower endoluminal pressure with a pressure limiter, which had no adverse effects on the endoscopist's feels on endoscopic procedures with the device.

Integrative analysis of miRNA-mRNA expression profiles in esophageal fibrosis after ESD.

The incidence of esophageal fibrosis and benign esophageal stricture (BES) has increased in recent years due to the curative therapy for early-stage esophageal carcinoma, including partial esophagectomy and esophageal endoscopic submucosal dissection (ESD). The aim of the present study was to identify key genes and associated pathways of esophageal fibrosis after the ESD procedure. During the esophageal ESD procedure, the esophageal tissue in the remaining submucosal layer, referred to as normal esophageal (NE) tissue, was collected, and 1 week thereafter, post-operative esophageal (PE) tissue was obtained. High-throughput sequencing was used to identify dysregulated microRNAs (miRNAs/miRs) between NE and PE tissues. According to the differentially expressed (DE) miRNAs, putative target genes were predicted. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes enrichment analysis and DEmiRNA interaction network analysis were performed. Reverse transcription-quantitative PCR (RT-qPCR) was performed to validate the RNA-sequencing results. A total of 199 miRNAs were determined to be DE between NE and PE tissues. Compared with the expression in the NE group, 83 miRNAs were significantly upregulated, while 116 miRNAs were significantly downregulated. According to these DE miRNAs, forkhead box O1 (FOXO1), paired box 6 (PAX6), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) and adrenoceptor β1 (ADRB1) were DE genes regulated by five DE miRNAs, including miR-223-3p, miR-142-5p, miR-582-5p, miR-21-3p and miR-218-5p. The results suggested that certain pathways were markedly dysregulated, including FOXO, MAPK, AMP-activated protein kinase and signaling pathways regulating the pluripotency of stem cells and proteoglycans in cancer. According to the RT-qPCR results, the expression levels of FOXO1, PAX6, ADRB1, miR-223-3p, miR-582-5p, miR-21-3p and miR-218-5p were consistent with the integrated analysis. In conclusion, FOXO1, PAX6, PIK3CA and ADRB1 may have a role in esophageal fibrosis, regulated by miR-223-3p, miR-142-5p, miR-582-5p, miR-21-3p and miR-218-5p. The present results provided an improved understanding of the changes in the microenvironment during the process of esophageal fibrosis, as well as novel potential targets for the treatment of esophageal fibrosis and BES.

Steroid injection and polyglycolic acid shielding to prevent stricture after esophageal endoscopic submucosal dissection: a retrospective comparative analysis (with video)

Postoperative stricture after expansive esophageal endoscopic submucosal dissection (ESD) is a severe adverse event. Previous single-arm reports have suggested that polyglycolic acid (PGA) shielding may prevent stricture. This study was performed to assess the efficacy of this method through a comparative analysis. This is a retrospective analysis of 500 consecutive cases of esophageal ESD performed between 2002 and 2018 at the University of Tokyo Hospital. After 2013, patients with a diagnosis of superficial esophageal carcinoma covering more than half of the esophageal circumference underwent preventive treatment with either PGA shielding or steroid injection+ PGA shielding after ESD. The efficacy of these methods for preventing post-ESD stricture was assessed through multivariable logistic regression analysis. The risk of postoperative stricture was especially high in the cervical esophagus (odds ratio [OR], 4.60; 95% confidence interval [CI], 0.65-61.09) and after total circumferential resection (OR, 3.58×103; lower bound of 95% CI, >185). Steroid injection+ PGA shielding was the only method significantly effective in preventing stricture (OR, 0.30; 95% CI, 0.10-0.78; P= .009). In the relatively low-risk subgroup (excluding cervical esophageal cancer and complete circumferential resection), the postoperative stricture rates for steroid injection+ PGA shielding versus PGA shielding versus control were 18.9% versus 41.4% versus 51.7%, respectively (P= .015). However, the efficacy of this was limited in extremely high-risk cases. The combination of steroid injection and PGA shielding is effective for preventing post-ESD stricture. There is a need for even more effective methods for cervical esophageal cancer and complete circumferential resection.

Feasibility of the lidocaine injection method during esophageal endoscopic submucosal dissection.

Background and AimEsophageal endoscopic submucosal dissection (ESD) is often technically difficult due to intraoperative body movements. The level of sedation can be increased to suppress body movements, but this may not be successful in all cases. Using local analgesics for submucosal injection during ESD may aid in conscious sedation. This study evaluated the feasibility of the lidocaine injection method (LIM) during esophageal ESD.MethodsTwenty‐nine patients with superficial esophageal cancer were enrolled in this study at Osaka Saiseikai Nakatsu Hospital, and 1% lidocaine + 0.4% hyaluronate sodium was injected into the submucosa underneath the lesion during esophageal ESD. The main outcome was body movements that disturbed the procedure.ResultsMost patients were male (90%), with a median age of 70 years (interquartile range [IQR]: 66–75 years old), and the median lesion size was 17 mm (IQR: 12–21 mm). The median injection volume of lidocaine was 70 mg (IQR: 55–79 mg). All lesions were successfully removed en bloc. In all cases, there were no body movements that disturbed the procedure. Regarding adverse events of sedation, five patients (17%) had hypotension, four patients (14%) had bradycardia, and seven patients (24%) had hypoxemia during ESD. Convulsions or arrhythmia as adverse events associated with lidocaine were not observed.ConclusionsEsophageal ESD with LIM did not cause body movements that disturbed the procedure. LIM may help create a stable conscious sedation method for esophageal ESD.

Predictive Factors of Postendoscopic Submucosal Dissection Electrocoagulation Syndrome and the Utility of Computed Tomography Scan after Esophageal Endoscopic Submucosal Dissection

Background/Aims: Recently, postendoscopic submucosal dissection electrocoagulation syndrome (PEECS) has attracted attention. However, the criteria for computed tomography (CT) scanning following esophageal endoscopic submucosal dissection (ESD) are unclear. In this study, we aimed to identify the predictive factors of PEECS and the usefulness of CT scanning after esophageal ESD. Methods: A total of 245 lesions in 223 patients who underwent esophageal ESD between February 2008 and October 2018 were retrospectively analyzed. Patients with double cancers, those who experienced procedural accidents, such as aspiration pneumonitis or perforation, and those who were unable to undergo CT were excluded from the study. PEECS evaluation items included body temperature (≤37.7°C = 1 point, ≥37.8°C = 2 points), white blood cell count (<10,800/μL = 1 point, ≥10,800/μL = 2 points), and chest pain (numerical rating scale [NRS] ≤4 = 1 point, NRS ≥5 = 2 points). Scores of ≥5 points were categorized as the PEECS-positive group, and scores of ≤4 points were categorized as the PEECS-negative group. The degree of mediastinal emphysema on CT was stratified into 5 grades, in which grades 0 and 1 were considered as the “low-grade” group, and grades 2, 3, and 4 were considered as the “high-grade” group. We analyzed the prognostic factors of high-grade mediastinal emphysema, including the presence or absence of PEECS. Results: The PEECS-positive group comprised 18 out of the 163 patients (11.0%), and mediastinal emphysema was stratified into grades 0 (94), 1 (51), 2 (12), 3 (5), and 4 (1 patient). Three independent risk factors for the onset of PEECS were identified, as follows: resected area ≥750 mm² (OR 7.28, 95% CI 1.42–37.33, p = 0.017), treatment duration ≥75 min (OR 10.26, 95% CI 1.20–87.77, p = 0.034), and muscle layer exposure (OR 10.92, 95% CI 2.22–53.74, p = 0.003). Two independent predictive factors of high-grade mediastinal emphysema were identified, which were PEECS positivity (OR 4.31, 95% CI 1.29–14.41, p = 0.018), and muscle layer exposure (OR 4.08, 95% CI 1.18–14.06, p = 0.026). Conclusions: A large resected area, prolonged treatment duration, and muscle layer exposure are risk factors for the onset of PEECS. Mediastinal emphysema was observed in 43% of patients following ESD. When marked clinical symptoms of PEECS appear, high-grade mediastinal emphysema may be observed, and therefore CT should be performed in these cases.

Mo1180 OFF-LABEL USE OF TEAR DROPS WITH SODIUM HYALURONATE FOR SUBMUCOSAL INJECTION IN ESOPHAGEAL ESD: IS IT SAFE AND EFFECTIVE?

Submucosal (SM) injection with viscous solution produces a long-lasting SM cushion and it is recommended for esophageal endoscopic submucosal dissection (ESD). A solution with 0.4% sodium hyaluronate (SH) named MucoUp® has been approved for SM injection and Japanese experts extensively use it. However this solution is expensive and unavailable outside Japan. Recently there has been an increased interest in the development of solutions to facilitate ESD. For the past 10 years we have used a low-cost readily available sterile tears drops solution composed of 0.4% SH for ESD. The aim of this study is to present the clinical outcome with the off label use of SH for SM injection in esophageal ESD.

Efficacy of Endoscopic Submucosal Dissection of Esophageal Neoplasms under General Anesthesia

Background/AimsEvidence that general anesthesia (GA) reduces the operative time of esophageal endoscopic submucosal dissection (ESD) is currently insufficient. This study aims to evaluate the efficacy and safety of esophageal ESD under GA. MethodsA total of 227 lesions from 198 consecutive patients with superficial esophageal neoplasms treated by ESD at 3 Japanese institutions between April 2011 and September 2017 were included in this retrospective study. For ESD, GA and deep sedation (DS) were used in 102 (51.5%, GA group) and 96 patients (48.5%, DS group), respectively. ResultsThere were no statistically significant differences in age, sex, or comorbidities between the groups. In the GA group, the tumor size was larger (21 [3–77] mm vs. 14 [3–63] mm, p<0.001), luminal circumference was larger (≥2/3; 13.9% vs. 5.4%, p=0.042), procedure time was shorter (28 [5–202] min vs. 40 [8–249] min, p<0.001), and submucosal dissection speed was faster (25.2 [7.8–157.2] mm2 /min vs. 16.2 [2.4–41.3] mm2 /min, p<0.001). The rates of intraoperative perforation and aspiration pneumonia were lower in the GA group, but the difference did not achieve statistical significance (p=0.242 and p=0.242). ConclusionsGA shortens the procedure time of esophageal ESD.

Continuous liquid-suction catheter attachment for endoscope reduces volume of liquid reflux to the mouth in esophageal endoscopic submucosal dissection.

Pooling of liquid in the esophageal lumen can worsen the field of vision and cause liquid reflux to the mouth, which leads to aspiration pneumonia, in esophageal endoscopic submucosal dissection (ESD). We developed a continuous liquid-suction catheter attachment for the endoscope (CLCA) that has multiple tiny holes and can suction the liquid without causing mucosal injury. Thus, we aim to show the efficacy of CLCA in esophageal ESD. This was a single-blinded, randomized controlled trial involving patients with superficial esophageal cancer. The enrolled patients were randomly assigned to the conventional ESD (C-ESD) or ESD with CLCA (CLCA-ESD) groups. Primary endpoint was volume of liquid reflux to the mouth during the ESD procedure. Secondary endpoints were incidence of aspiration pneumonia and procedure time. Fifty patients were enrolled in this trial. Volume of liquid reflux to the mouth was significantly lower in the CLCA-ESD group than in the C-ESD group (mean: 10 vs 73mL, P=0.010). Furthermore, the incidence of aspiration pneumonia on computed tomography (CT) scan between the two groups was also significantly different (4.0% vs 32.0%, P=0.023), although no significant difference was observed through chest radiography. In addition, procedure time tended to be shorter in the CLCA-ESD group (P=0.054). This study first showed that use of CLCA in esophageal ESD reduced the volume of liquid reflux to the mouth and contributed to decreased incidence of aspiration pneumonia on CT scan (UMIN000018167).

Management of adverse events related to endoscopic resection of upper gastrointestinal neoplasms: Review of the literature and recommendations from experts.

Prevention therapy is recommended for lesions >1/2 of the esophageal circumference. Locoregional steroid injection is recommended for lesions >1/2-3/4 of the esophageal circumference and oral steroids are recommended for lesions >1/2 of the subtotal circumference. For lesions of the entire circumference, oral steroid combined with injection steroid is considered. Endoscopic balloon dilatation (EBD) is the first choice of treatment for stricture after esophageal endoscopic submucosal dissection (ESD). Radical incision and cutting or self-expandable metallic stent can be considered for refractory stricture after EBD. In case of intraoperative perforation during esophageal ESD, endoscopic clip closure should be initially attempted. Surgery is considered for treatment of delayed perforation. Current standard practice for prevention of delayed bleeding after gastric ESD includes prophylactic coagulation of vessels on post-ESD ulcers and giving proton pump inhibitors. Chronic kidney disease stage 4 or 5, multiple antithrombotic drug use, anticoagulant use, and heparin bridging therapy are high-risk factors for delayed bleeding after gastric ESD. Intraoperative perforation during gastric ESD is initially managed by endoscopic clip closure. If endoscopic clip closure is difficult, other methods such as over-the-scope clip (OTSC), polyglycolic acid (PGA) sheet shielding etc. are attempted. Delayed perforation usually requires surgical intervention, but endoscopic closure by OTSC or PGA sheet may be considered. Resection of three-quarters of the circumference is a risk factor for stenosis after gastric ESD. Giving prophylactic local steroid injection and/or oral steroid is reported, but effectiveness has not been fully verified as has been done for esophageal stricture. The main management method for gastric stenosis is EBD but it may cause perforation.

Safety of Carbon Dioxide Insufflation during Endoscopic Submucosal Dissection for Esophageal Squamous Cell Carcinoma

Background: Pulmonary dysfunction often accompanies esophageal squamous cell carcinoma (SCC). Aims: This study examined the use of carbon dioxide (CO₂) insufflation and its safety during esophageal endoscopic submucosal dissection (ESD) while under conscious sedation. Methods: ESD using CO₂ insufflation (1.4 L/min) was performed in 102 consecutive esophageal SCC patients. Patients with a forced expiratory volume of 1.0 s/forced vital capacity (FEV_1.0%) < 70% or a vital capacity < 80% were defined as having pulmonary dysfunction. Transcutaneous partial pressure of CO₂ (PtcCO₂) was recorded before, during, and after ESD. Results: A history of smoking was found in 90 patients (88%), while 43 patients (42%) had pulmonary dysfunction. No significant differences were found between the pulmonary dysfunction and normal groups for the baseline PtcCO₂ before ESD, peak PtcCO₂ during ESD, and median PtcCO₂ after ESD. There was a significant correlation between the PtcCO₂ elevation from baseline and the ESD procedure time (r = 0.32, p < 0.01), with the correlation for the pulmonary dysfunction group much stronger (r = 0.39, p < 0.05) than that for the normal group (r = 0.30, p < 0.01). Neither of the groups exhibited any differences for either the complication incidence or the hospital stay. Conclusions: Although the use of CO₂ insufflation during esophageal ESD under conscious sedation is safe with regard to the risk of complications, longer procedure times can potentially induce CO₂ retention in patients with obstructive lung disease. Thus, it is necessary to both shorten the procedure times and perform CO₂ monitoring.

Impact of electrosurgical unit mode on post esophageal endoscopic submucosal dissection stricture in an in vivo porcine model.

Background and aim Strictures are a major complication of esophageal endoscopic submucosal dissection (ESD) for superficial esophageal carcinoma. Post ESD, stricture develops during the process of scar formation, which is related to inflammation caused by ESD. We planned a study to evaluate whether certain electrosurgical unit modes could attenuate strictures after esophageal ESD. Methods A total of 16 ESD, three-quarters of the esophageal circumference, were performed in four live pigs. A ball-tip Flush knife was used for mucosal incision. Submucosal dissection was performed using a Hook knife in monopolar mode and a ball-tip Jet B-knife in bipolar mode. Applied electrosurgical unit modes were FORCED COAG, SWIFT COAG, SPRAY COAG, ENDO CUT in monopolar mode, and FORCED COAG in bipolar mode. One month after ESD, the pigs were killed humanely and the severity of strictures and fibrosis was assessed. Results The resected site in the esophagus showed complete mucosal regrowth and scar formation in all pigs. The quotients of stricture following ENDO CUT, SWIFT COAG, FORCED COAG effect2, FORCED COAG effect3, FORCED COAG effect4, SPRAY COAG, and Bipolar FORCED COAG mode were 16 %, 28 %, 38 %, 33 %, 51 %, 39 %, and 47 %, respectively. The equivalent quotients of fibrosis were 7 %, 28 %, 31 %, 30 %, 35 %, 63 %, and 100 %, respectively. ENDO CUT mode was associated with the lowest mean quotients of stricture and fibrosis. Conclusion ENDO CUT mode showed promising results to attenuate fibrosis and strictures after esophageal ESD.