Pocket-creation Method Research Articles

Tunneled or Pocket Creation Method Versus Conventional Endoscopic Submucosal Dissection for Gastric Lesions: A Systematic Review and Meta-analysis

Tunneled endoscopic submucosal dissection (T-ESD) and pocket creation-method ESD (PCM-ESD) are considered to have technical advantages over conventional ESD (C-ESD). However, data comparing these techniques for ESD of gastric lesions are limited. PubMed and Cochrane databases were reviewed for relevant studies from their inceptions to October 31, 2023. Studies comparing T-ESD or PCM-ESD (T/PCM-ESD) with C-ESD for gastric lesions were included. The primary outcomes were dissection speed and en-bloc resection. Secondary outcomes were R0 resection, recurrence, perforation, and post-ESD bleeding. A random effects meta-analysis was conducted. Eight observational studies (359 patients with T/PCM-ESD, 670 patients with C-ESD) were included. T/PCM-ESD was associated with a significantly faster dissection speed (mean difference, 4.42mm2/min; 95% confidence interval [CI], 2.05-6.79; I2= 79%). There were no significant differences between the groups in terms of en-bloc resection (risk ratio [RR], 1.01; 95% CI, 1.00-1.03; I2= 0%), R0 resection (RR, 1.03; 95% CI, 0.99-1.07; I2= 0%), and recurrence (RR, 0.73; 95% CI, 0.14-3.84; I2= 0%). Although T/PCM-ESD was associated with a significantly lower risk of perforation (RR, 0.21; 95% CI, 0.06-0.80; I2= 0%), post-ESD bleeding rates were not significantly different. T/PCM-ESD facilitates faster and safer gastric ESD than C-ESD, with similar en-bloc resection, R0 resection, and recurrence rates. A future randomized controlled control trial is required.

Multicenter prospective randomized controlled clinical trial comparing the pocket-creation method with and without single-clip traction of colonic endoscopic submucosal dissection.

The pocket-creation method (PCM) was developed to overcome the technical difficulties of endoscopic submucosal dissection (ESD), although opening the pocket remains challenging. We developed a novel technique of PCM with single-clip traction (PCM-CT), which uses a reopenable clip as a traction device to maintain stability during the procedure. No prospective study has compared the efficacy of PCM-CT and PCM. This study aimed to investigate the effectiveness of PCM-CT vs. PCM in a randomized controlled trial. This randomized controlled clinical trial was conducted at four Japanese institutions. Patients with superficial colorectal neoplastic lesions were included following Japanese guidelines for colorectal cancer. Seven moderately experienced endoscopists performed the ESD procedures using either PCM-CT or PCM. 100 patients were enrolled in the study. Compared with PCM, PCM-CT achieved significantly faster mean (SD) dissection speed (21.4 [10.8] vs. 27.0 [14.5] mm2/min [95%CI 0.5 to 10.7], P = 0.03), and reduced the mean procedure time (81.8 [57.9] vs. 64.8 [47.6] minutes [95%CI -38.2 to 4.3], P = 0.12) and pocket-opening time (37.8 [33.0] vs. 30.0 [28.9] minutes [95%CI -20.2 to 4.6], P = 0.22). En bloc and R0 resection rates were not significantly different between the two groups (100% vs. 100%, P >0.99; 100% vs. 96%, P = 0.50, respectively). No significant differences were observed in adverse events between the two groups. ESD facilitated by the novel PCM-CT method appeared to be significantly faster than PCM. Both methods achieved high R0 resection rates.

A prospective randomized trial comparing the pocket-creation method and conventional method of endoscopic submucosal dissection in early gastric cancers and precancerous lesions

BackgroundEndoscopic submucosal dissection (ESD) is widely used as a standard treatment regimen for early gastric cancers (EGCs). However, such an approach is time consuming and has a high risk of perforation and bleeding in some corner-site lesions because of the obscured view and difficulty in submucosal lifting. The newly developed pocket-creation method (PCM) provides a clearer view and better traction of the submucosal layer than conventional ESD (c-ESD). Nevertheless, no prospective randomized study has evaluated the efficacy of the PCM in EGCs and precancerous lesions. MethodsThis was a prospective randomized controlled trial. Patients with superficial gastric neoplastic lesions ≥ 20 mm were randomly assigned to the PCM-ESD group or c-ESD group. The primary outcome was dissection speed. ResultsThere were 28 patients in the PCM-ESD group and 27 in the c-ESD group. The median dissection speed was significantly higher in the PCM-ESD group than in the c-ESD group (21.5 mm2/min vs 14.3 mm2/min, P < .001). Meanwhile, the operation time in the PCM-ESD group was significantly shorter than that in the c-ESD group (30 vs 40 min, P = .047). In multiple linear regression analysis, the treatment method was independently associated with the resection speed of ESD. ConclusionPCM-ESD was an effective and safe treatment for EGCs and precancerous lesions.

Endoscopic Treatment for Submucosal Heterotopic Gastric Gland in a Case Observed over Nine Years from Development to Enlargement.

A 70-year-old Japanese man with a submucosal gastric mass that continued to increase in size underwent endoscopic submucosal dissection using the pocket creation method. Histologically, some epithelial cell nuclei were enlarged, but there was little atypia overall and no sign of malignancy, suggesting a diagnosis of submucosal heterotopic gastric gland (SHGG). SHGG that enlarges over time has been associated with gastric cancer, but a preoperative diagnosis is difficult. This case was very valuable, as it enabled us to follow the course of SHGG over a period of about nine years, from the onset to enlargement.

A successful case of an endoscopic submucosal dissection using a combination of the pocket-creation method and traction with a spring-and-loop with clip for early gastric cancer with severe ulcer scarring.

Video 1ESD for gastric cancer with severe scarring using PCM and S-O clip.

Pancreatitis and cholangitis caused by metallic wire in the duodenal submucosa and muscularis near the papilla: removal by endoscopic submucosal dissection using the pocket-creation method.

Video 1A metalic wire removed by endoscopic submucosal dissection using the pocket-creation method.

Nasogastric-tube decompression facilitates the pocket-creation method of gastric endoscopic submucosal dissection.

Nasogastric-tube decompression facilitates the pocket-creation method of gastric endoscopic submucosal dissection.

Diagnostic and therapeutic strategies for colorectal tumor with positive muscle-retracting sign.

Endoscopic submucosal dissection (ESD) for colorectal tumors with positive muscle-retracting (MR) sign often results in incomplete resection or discontinuation owing to the difficulty of submucosal dissection. The present study aimed to evaluate the usefulness of endoscopic ultrasonography (EUS) in diagnosing the MR sign and performing ESD using the pocket-creation method (PCM). Thirty-six cases of colorectal tumors with positive MR sign during ESD between January 2015 and December 2021 were retrospectively reviewed. Cases were divided into two groups: 1) the conventional method (CM) group, comprising 29 cases, and 2) the PCM group with seven cases, in which preoperative EUS and ESD using PCM were performed. Treatment outcomes were compared between the groups. The diagnostic yield of EUS for the MR sign was evaluated among large sessile tumors >20 mm in which preoperative EUS was performed. Histologic diagnosis was adenoma or Tis carcinoma in 12 cases (33%), T1 carcinoma in 18 cases (50%), T2 carcinoma in four cases (11%), and unevaluable in two cases (6%). The sensitivity and specificity of the EUS-MR sign for large sessile tumors were 87.5% and 83.3%, respectively. ESD was achieved in all cases in the PCM group, although it was discontinued in eight cases (28%) in the CM group. There were significant differences between the PCM and CM groups in en bloc resection (100% vs. 48%, p = 0.013) and R0 resection rates (71% vs. 31%, p = 0.049). The MR sign can be predicted by preoperative EUS, and ESD using PCM allows en bloc resection.

Use of a traction device facilitates opening of the pocket during the pocket-creation method of gastric endoscopic submucosal dissection.

The pocket-creation method (PCM) is a strategy to achieve safe and high quality endoscopic submucosal dissection (ESD) throughout the alimentary tract [1] [2] [3] [4]. While the pocket is being created, the PCM enables endoscopists to effectively apply traction and countertraction using the tip of the hood alone. In this phase, the PCM can be considered a traction method; however, because stabilization of the endoscope tip and traction force gradually reduces while the pocket is being opened, it may become difficult and time-consuming. Particularly during gastric ESD, it is difficult to change the patient’s position and, as a result, it may not be possible to use gravity effectively, depending on the location of the lesion. We devised a new strategy for the PCM using traction devices when opening the pocket during gastric ESD ([Fig. 1]), as we have reported in the past for colorectal ESD [5].

Endoscopic submucosal dissection techniques and technology: European Society of Gastrointestinal Endoscopy (ESGE) Technical Review.

ESGE suggests conventional endoscopic submucosal dissection (ESD; marking and mucosal incision followed by circumferential incision and stepwise submucosal dissection) for most esophageal and gastric lesions. ESGE suggests tunneling ESD for esophageal lesions involving more than two-thirds of the esophageal circumference. ESGE recommends the pocket-creation method for colorectal ESD, at least if traction devices are not used. The use of dedicated ESD knives with size adequate to the location/thickness of the gastrointestinal wall is recommended. It is suggested that isotonic saline or viscous solutions can be used for submucosal injection. ESGE recommends traction methods in esophageal and colorectal ESD and in selected gastric lesions. After gastric ESD, coagulation of visible vessels is recommended, and post-procedural high dose proton pump inhibitor (PPI) (or vonoprazan). ESGE recommends against routine closure of the ESD defect, except in duodenal ESD. ESGE recommends corticosteroids after resection of > 50 % of the esophageal circumference. The use of carbon dioxide when performing ESD is recommended. ESGE recommends against the performance of second-look endoscopy after ESD. ESGE recommends endoscopy/colonoscopy in the case of significant bleeding (hemodynamic instability, drop in hemoglobin > 2 g/dL, severe ongoing bleeding) to perform endoscopic hemostasis with thermal methods or clipping; hemostatic powders represent rescue therapies. ESGE recommends closure of immediate perforations with clips (through-the-scope or cap-mounted, depending on the size and shape of the perforation), as soon as possible but ideally after securing a good plane for further dissection.

Outcomes of the Conventional versus Pocket-Creation Method for Endoscopic Submucosal Dissection of Gastric Body Tumors Using a Dual Knife: A Retrospective Study.

Various endoscopic submucosal dissection (ESD) methods for gastric tumors have been tried. However, no studies have yet compared results according to the ESD method for gastric body tumors using a dual knife. The objective of this study was to compare outcomes of two ESD methods for gastric body tumors: the pocket-creation method and conventional method. Patients who underwent ESD for a gastric body tumor were retrospectively reviewed. Patients were divided into two groups according to the ESD method: the conventional method (group I) and pocket-creation method (group II). Characteristics of patients and tumors, hospitalization period, incidence of complications, resection margin status, incidence of surgical operation, procedure time, and laboratory findings were investigated. Of the total of 100 patients, 52 belonged to group I and 48 to group II. All tumors were successfully resected en bloc. Resection margin involvement was found in six (11.5%) of group I and six (12.5%) of group II. Complications were observed in seven (13.5%; major complication five, minor two) of group I and eight (16.7%; major two, minor six) of group II. There were no significant differences in ESD outcomes such as hospitalization period, incidence of complications, resection margin status, incidence of surgical operation, procedure time, or inflammatory response after ESD between the two groups. Both methods are suitable for treating gastric body tumors with adequate treatment success rates and comparable complication rates.

Efficacy and safety of pocket-creation method for early gastric cancers.

Endoscopic submucosal dissection (ESD) is the standard endoscopic treatment for early gastric cancers (EGCs). However, obscured view and difficulty in submucosal lifting during ESD have been demonstrated. Additionally, ESD is time-consuming and poses a high risk of perforation and bleeding when performed in challenging locations. The pocket-creation method (PCM) is a newly developed strategy for colorectal tumors, while the outcomes of application in the treatment of EGCs are rarely reported. In the present study, we aimed to compare the technical efficacy and safety of PCM-ESD and the conventional ESD (c-ESD) technique for the treatment of EGCs. This was a single-center retrospective study consisting of 162 patients with EGCs who underwent ESD between February 2019 and February 2021. One-to-one propensity score matching (PSM) was performed. In addition, clinicopathological characteristics and treatment outcomes were also compared. PCM-ESD was more likely to be used in patients with larger lesions than c-ESD with/without traction. In addition, the resection speed for lesions of the PCM-ESD was faster compared with c-ESD without traction (median dissection speed: 19.6mm2/min vs. 15mm2/min; p < 0.001) and c-ESD with traction (median dissection speed after PSM: 19.9mm2/min vs. 15mm2/min; p = 0.001). In multiple linear regression analysis, significant factors related to a higher dissection speed were the treatment method of PCM-ESD (p = 0.034), the long diameter of the resected lesion (p = 0.001), and lesion location (p = 0.046). Collectively, PCM-ESD appeared to be a safer and more effective treatment for EGCs than c-ESD. In addition, PCM-ESD could significantly improve the speed of tumor resection.

Complete resection of residual rectal dysplasia in a patient with ulcerative colitis using the pocket-creation method.

Complete resection of residual rectal dysplasia in a patient with ulcerative colitis using the pocket-creation method.

Efficacy of the pocket-creation method with a traction device in endoscopic submucosal dissection for residual or recurrent colorectal lesions.

Background/AimsEndoscopic submucosal dissection (ESD) for residual or recurrent colorectal lesions after incomplete resection is challenging because of severe fibrosis. This study aimed to compare the efficacy of the pocket-creation method (PCM) with a traction device (TD) with that of conventional ESD for residual or recurrent colorectal lesions. MethodsWe retrospectively studied 72 patients with residual or recurrent colorectal lesions resected using ESD. Overall, 31 and 41 lesions were resected using PCM with TD and conventional ESD methods, respectively. We compared patient background and treatment outcomes between the PCM with TD and conventional ESD groups, respectively. The primary endpoints were en bloc resection and R0 resection rates. The secondary endpoints were the dissection speed and incidence of adverse events. ResultsEn bloc resection was feasible in all cases with PCM with TD, but failed in 22% of cases of conventional ESD. The R0 resection rates for PCM with TD and conventional ESD were 97% and 66%, respectively. Dissection was significantly faster in the PCM with TD group (13.0 vs. 7.9 mm2/min). Perforation and postoperative bleeding were observed in one patient in each group. ConclusionsPCM with TD is an effective method for treating residual or recurrent colorectal lesions after incomplete resection.

Endoscopic Submucosal Dissection of Deeply Invasive Colorectal Cancers Using the Pocket-Creation Method: Analysis of Vertical Margins

Background and aimsThe standard treatment for stage T1b colorectal cancers with 1,000µm or greater submucosal invasion is surgical resection. However, the risk of lymph node metastases is only 1-2% when excluding risk factors for metastases other than depth of submucosal invasion. The number of elderly patients with significant comorbidities is increasing with societal aging in Japan. Therefore, local endoscopic resection of T1b colorectal cancers needs more consideration in the future. We previously showed that the pocket-creation method (PCM) for endoscopic submucosal dissection (ESD) is useful regardless of the morphology, including large sessile tumors with submucosal fibrosis, or location of the colorectal tumor. However, some T1b colorectal cancers have pathologically positive margins even when using the PCM. We retrospectively investigated the causes of failure to achieve negative vertical margins.MethodsWe retrospectively analyzed 953 colorectal tumors in 886 patients resected with the PCM. Finally, 65 pathological T1b colorectal cancers after en bloc resection were included in this study. ESD specimens and recorded procedure videos of T1b cancer resections with pathologically positive vertical margins were reviewed.ResultsThe 65 cancers were divided into positive vertical margin (VM+ group) and negative vertical margin (VM- group) groups with 10 [10/65 (15%)] and 55 [55/65 (85%)] patients in each group, respectively. There was a significant difference in the rate of submucosal fibrosis (P=0.012) and dissection speed (P=0.044). There were no significant differences between the two groups in other regards. When verifying 8/10 available videos in the VM+ group, endoscopic technical factors led to positive vertical margins in five patients, and essential pathological factors of ESD led to positive vertical margins in the other three. Six of these eight patients underwent additional surgical resection. No residual tumor was identified in six T1b cancers. None of these six resected specimens contained lymph node metastases on pathological examination.ConclusionThe PCM resulted in a high rate of negative-vertical-margin resections. The PCM resulted in complete resection of T1b cancers when examining additional surgical specimens. ESD using the PCM is a viable option for the endoscopic treatment of T1b colorectal cancers.

Effectiveness and safety of endoscopic submucosal dissection using the pocket creation method in the Japanese population: a systematic review and meta-analysis.

Background and study aims Endoscopic submucosal dissection (ESD) is a standard method for minimally invasive resection of superficial gastrointestinal tumors. The pocket creation method (PCM) facilitates ESD regardless of location in the gastrointestinal tract. The aim of this systematic review and meta-analysis is to evaluate the effectiveness and safety of ESD for superficial neoplasms in the upper and lower gastrointestinal tract comparing the PCM to the non-PCM. Methods Randomized controlled, prospective, and retrospective studies comparing the PCM with the non-PCM were included. Outcomes included en bloc resection, R0 resection, dissection speed, delayed bleeding and perforation. Pooled odds ratios (ORs) with 95 % confidence intervals (CIs) using the Mantel-Haenszel random effect model were documented. Results Eight studies including gastric, duodenal, and colorectal ESD were included. The en bloc resection rate was significantly higher in the PCM group than the non-PCM group (OR 3.87, 95 %CI 1.24–12.10 P = 0.020). The R0 resection rate was significantly higher in the PCM group than the non-PCM group (OR 2.46, 95 %CI 1.14–5.30, P = 0.020). The dissection speed was significantly faster in the PCM group than the non-PCM group (mean difference 3.13, 95 % CI 1.35–4.91, P < 0.001). The rate of delayed bleeding was similar in the two groups (OR 1.13, 95 %CI 0.60–2.15, P = 0.700). The rate of perforation was significantly lower in the PCM group than the non-PCM group (OR 0.34, 95 %CI 0.15–0.76, P = 0.009). Conclusions The PCM facilitates high-quality, fast and safe colorectal ESD. Further studies are needed regarding the utility of PCM in ESD of the upper gastrointestinal tract.

A traction wire facilitates the pocket-creation method for endoscopic submucosal dissection in the cecum.

A traction wire facilitates the pocket-creation method for endoscopic submucosal dissection in the cecum.

The Pocket-Creation Method Facilitates Endoscopic Submucosal Dissection of Gastric Neoplasms Along the Lesser Curvature at the Gastric Angle.

BackgroundEndoscopic submucosal dissection (ESD) of superficial gastric lesions located along the lesser curvature at the gastric angle is a challenging situation due to paradoxical movement and a protruding angle. The pocket-creation method (PCM) can overcome this difficulty by stabilizing the tip of the endoscope in the pocket and minimizing insufflation of the stomach, which enables horizontal and straight dissection. This study aims to clarify whether the PCM improves the technical outcomes of ESD of superficial gastric neoplasms along the lesser curvature at the angle.MethodsFrom October 2006 to June 2021, 158 gastric lesions along the lesser curvature at the angle were resected with needle-type knives. We retrospectively reviewed the records and divided them into the PCM group (n = 61) and the conventional method (CM) group (n = 97). The primary outcome measurement was dissection speed (in mm2/min).ResultsThe two groups were not significantly different for baseline characteristics such as macroscopic type and size except for the proportion of adenomas. The proportion of expert endoscopists was not significantly different between the two groups (P = 0.141). The dissection speed was significantly faster in the PCM group than in the CM group (P = 0.001). There were no holes in the resected specimens in the PCM group, while five lesions in the CM group (5%) had a hole (P = 0.182). There were no significant differences in the incidence of adverse events.ConclusionsThis is the first study to show that the PCM outperforms the CM for ESD of lesions located along the lesser curvature at the gastric angle. The PCM facilitated ESD of these lesions by significantly increasing dissection speed when a needle-type knife is used with no increase in adverse events.

The usefulness of combining the pocket-creation method with a traction device using a scissor-type knife for colorectal endoscopic submucosal dissection.

Technical issues and long procedure time still remain a concern in colorectal endoscopic submucosal dissection (ESD). We examined the usefulness of combining the pocket-creation method (PCM) with a traction device (S-O clip; SO) using a scissor-type knife (Clutch Cutter 3.5mm; CC) for decreasing ESD procedure time. We retrospectively analyzed 95 ESD cases of PCM + SO + CC managed from August 2017 to April 2020 and 103 cases of PCM + CC treated from July 2016 to July 2017. We compared these two groups through propensity score matching. The main outcome was the analysis of the ESD procedure times under various conditions in each group. After matching, 52 cases in the PCM + SO + CC and PCM + CC groups were analyzed. The PCM + SO + CC group showed a significantly shorter ESD procedure time than the PCM + CC group (57.8 ± 31.4 vs. 81.7 ± 33.5min, p < 0.01). Additionally, the ESD procedure time was significantly shorter in the PCM + SO + CC group than in the PCM + CC group: tumor size (tumor size < 40mm: 45.6 ± 15.8 vs. 72.7 ± 22.9min, p < 0.01; tumor size ≥ 40mm: 83.1 ± 40.1 vs. 111.8 ± 45.3min, p = 0.04), tumor location (right side: 64.7 ± 33.3 vs. 81.0 ± 29.7min, p = 0.03; left side: 50.5 ± 28.0 vs. 82.3 ± 36.9min, p < 0.01), tumor morphology (polypoid: 39.2 ± 18.6 vs. 74.7 ± 28.6min, p < 0.01; nonpolypoid: 62.3 ± 32.3 vs. 84.5 ± 35.2min, p < 0.01), endoscopist (expert: 67.3 ± 41.2 vs. 91.9 ± 40.2min, p = 0.02; nonexpert: 50.4 ± 18.3 vs. 73.6 ± 24.9min, p < 0.01), and fibrosis (severe fibrosis: 82.0 ± 20.5 vs. 99.8 ± 40.4min, p = 0.169; non-severe fibrosis: 52.1 ± 23.8 vs. 75.6 ± 29.0min, p < 0.01). The combination of the PCM and SO using CC achieved a reduction in the colorectal ESD procedure time.

The pocket-creation method of endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is rapidly becoming the standard treatment for superficial gastrointestinal tumors because ESD can achieve complete local resection facilitating thorough pathological examination of the resected specimen. The pocket-creation method (PCM) has been established to perform safe and reliable ESD obtaining a high-quality pathological specimen. A minimal mucosal incision using PCM minimizes leakage of submucosally injected solution, which results in prolonged mucosal elevation. A limited-space submucosal pocket created using PCM makes the endoscope tip stable. A conical cap, small-caliber-tip transparent (ST) hood is used when performing PCM. The submucosa can be cut along the ideal dissection line just above the muscularis with minimal thermal damage because the tip of the ST hood produces both traction and countertraction to stretch the submucosal tissue in the pocket. PCM is recommended as the standard strategy not only for colorectal ESD but also for upper-gastrointestinal ESD. It is expected that the use of traction techniques will make PCM easier to perform.