Novel gastric endoscopic submucosal dissection training model enhances the endoscopic submucosal dissection skills of trainees: a multicenter comparative study.

BACKGROUND: Endoscopic submucosal dissection (ESD) requires high endoscopic technical skills, and trainees should develop effective training methods. In collaboration with KOTOBUKI Medical, we developed the G-Master, which is a non-animal training model that can simulate various parts of gastric ESD. We aimed to clarify the usefulness of the G-Master for inexperienced ESD trainees. METHODS: We collected data from the first 5 gastric ESD cases conducted by 15 inexperienced ESD trainees at 5 participating centers between 2018 and 2022. The participants were divided into two groups: the G-Master training and non-G-Master training groups. Outcome measurements, such as procedural speed, perforation rate, self-completion rate, and en bloc resection rate, were compared between the two groups retrospectively. RESULTS: A total of 75 gastric ESD cases were included in this study. The G-Master training group included 25 cases performed by 5 trainees, whereas the non-G-Master training group included 50 cases performed by 10 trainees. The median procedural speed for all cases was significantly faster in the G-Master training group than in the non-G-Master training group. Moreover, the procedural speed was linearly improved from the initial to the last cases in the lower location in the G-Master training group compared with the non-G-Master training group. In addition, although there was no significant difference, the G-Master training group showed lower rates of perforation and a lesser need to transition to expert operators than the non-G-Master training group. CONCLUSION: The G-Master could improve the ESD skills of inexperienced ESD trainees.

Clinical course of small gastric subepithelial lesion less than 20 mm diagnosed by endoscopic ultrasound-guided fine-needle aspiration.

BACKGROUND AND AIM: Gastrointestinal stromal tumors (GISTs) are treated as malignant gastric subepithelial lesions (SELs), and resection is recommended. However, small gastric SELs < 20 mm with no malignant features are monitored without histopathological examination, and the frequency of malignancy is unknown. This study aimed to clarify the clinicopathological findings and clinical course of gastric SELs < 20 mm measured by endoscopic ultrasound (EUS). METHODS: This retrospective cohort study included consecutive patients with small gastric SELs < 20 mm diagnosed using EUS at a tertiary referral center between 2009 and 2021. The clinical course after diagnosis using EUS-guided fine-needle aspiration (EUS-FNA) was reviewed. RESULTS: Among 333 patients with small gastric SELs, 104 patients with 105 lesions underwent EUS-FNA. The pathological diagnosis was confirmed in 87 patients. GISTs were the most common pathology (47%). Among the 87 patients, 43 underwent therapeutic interventions, including tumor resection and chemotherapy. In groups of tumor resection, the pathological tumor size on the resected specimen was significantly larger than the size measured by EUS (19.5 mm vs 15.0 mm, P < 0.001), and 37% of resected SELs were 20 mm or over. No recurrence was observed after tumor resection during a mean follow-up period of 40 months. CONCLUSIONS: Approximately 40% of small gastric SELs were malignant tumors, such as GIST, with most of them requiring treatment. Additionally, considering that the EUS measurement is 5 mm smaller than the pathological tumor diameter, further examinations, such as systematic EUS-FNA, may be required for SEL, including those smaller than 20 mm.

Efficacy of endoscopic submucosal resection with a ligation device for small rectal neuroendocrine tumor: study protocol of a multicenter open-label randomized control trial (BANDIT trial).

BACKGROUND: Endoscopic resection is widely accepted as a local treatment for rectal neuroendocrine tumors sized ≤ 10 mm. However, there is no consensus on the best method for the endoscopic resection of rectal neuroendocrine tumors. As a simplified endoscopic procedure, endoscopic submucosal resection with a ligation device (ESMR-L) indicates a histologically complete resection rate comparable to that of endoscopic submucosal dissection (ESD). We hypothesized that ESMR-L than ESD would be preferred for rectal neuroendocrine tumors. Hence, this trial aimed to verify whether ESMR-L is non-inferior to ESD in terms of histologically complete resection rate. METHODS: This is a prospective, open-label, multicenter, non-inferiority, randomized controlled trial of two parallel groups, conducted at the Shizuoka Cancer Center and 31 other institutions in Japan. Patients with a lesion endoscopically diagnosed as a rectal neuroendocrine tumor ≤ 10 mm are eligible for inclusion. A total of 266 patients will be recruited and randomized to undergo either ESD or ESMR-L. The primary endpoint is the rate of en bloc resection with histologically tumor-free margins (R0 resection). Secondary endpoints include en bloc resection rate, procedure time, adverse events, hospitalization days, total devices and agents cost, adverse event rate between groups with and without resection site closure, outcomes between expert and non-expert endoscopists, and factors associated with R0 resection failure. The sample size is determined based on the assumption that the R0 resection rate will be 95.2% in the ESD group and 95.3% in the ESMR-L group, with a non-inferiority margin of 8%. With a one-sided significance level of 0.05 and a power of 80%, 226 participants are required. Assuming a dropout rate of 15%, 266 patients will be included in this study. DISCUSSION: This is the first multicenter randomized controlled trial comparing ESD and ESMR-L for the R0 resection of rectal neuroendocrine tumors ≤ 10 mm. This will provide valuable information for standardizing endoscopic resection methods for rectal neuroendocrine tumors. TRIAL REGISTRATION: Japan Registry of Clinical Trials, jRCTs042210124. Registered on Jan 6, 2022.

Potential for expanding indications and curability criteria of endoscopic resection for early gastric cancer in elderly patients: results from a Japanese multicenter prospective cohort study.

BACKGROUND AND AIMS: Evidence for endoscopic resection (ER) in elderly patients with early gastric cancer (EGC) is limited. We assessed its clinical outcomes, and explored new indications and curability criteria. METHODS: We analyzed data from a Japanese multicenter prospective cohort study. Patients aged ≥75 years with EGC treated with ER were included. We classified "eCuraC-2 (corresponding to noncurative ER, defined in the Japanese gastric cancer treatment guidelines)" into "elderly-high (EL-H)" (>10% estimated metastatic risk) and "elderly-low (EL-L)" (≤10%). RESULTS: In total, 3,371 patients with 3,821 EGCs were included; endoscopic submucosal dissection (ESD) was the prominent treatment choice. Among them, 3,586 lesions met the guidelines' ER indications and 235 did not. The proportions of en bloc and R0 resections and perforations were 98.9%, 94.4%, and 0.8%, respectively, in EGCs within the indications. In EGCs beyond the indications, they were 99.5%, 85.4%, and 5.9%, respectively, for lesions diagnosed as ≤3 cm, and 96.0%, 64.0%, and 18.0% for those >3 cm. Curative ER ("eCuraA/B") and EL-L were observed in 83.6% and 6.2% of lesions within the indications, respectively, and in 44.2% and 16.8% of lesions <3 cm beyond the indications, respectively. The 5-year cumulative gastric cancer death rates following eCuraA/B and EL-H were 0.3% (95% CI, 0.2-0.6) and 3.5% (2.0-5.7), respectively. Following EL-L, the rate was 0.9% (0.2-3.5) even without subsequent treatment. CONCLUSIONS: Usefulness of ESD for elderly EGC patients was confirmed by their clinical outcomes. Lesions ≤3 cm and EL-L emerged as new ER indication and curability criterion, respectively.

Predictors of severe submucosal fibrosis during endoscopic submucosal dissection in patients with ulcerative colitis: Retrospective cohort study.

OBJECTIVES: Severe submucosal fibrosis is a crucial technical difficulty encountered during endoscopic submucosal dissection (ESD) in patients with ulcerative colitis (UC). We aimed to identify predictors of severe submucosal fibrosis in patients with UC. METHODS: We retrospectively included 55 tumors resected using ESD from 48 consecutive patients with UC. We analyzed the clinicopathological characteristics and treatment outcomes between the F0/1 (none to mild submucosal fibrosis) group (n = 28) and F2 (severe submucosal fibrosis) group (n = 27). RESULTS: No significant difference was found between the F0/1 and F2 groups in en bloc resection rate (100% vs. 96%, P = 0.49), the R0 resection rate (100% vs. 93%, P = 0.24), and the dissection speed (0.18 vs. 0.13 cm2 /min, P = 0.07). Intraoperative perforation was more common in the F2 group (30%) than in the F0/1 group (8%; P = 0.01). Multivariable analysis showed that a longer duration of UC (≥10 years; odds ratio [OR] 6.11; 95% confidence interval [CI] 1.20-31.03; P = 0.03) and scarring of background mucosa of the tumor (OR 39.61; 95% CI 3.91-400.78; P < 0.01) were independent predictors of severe submucosal fibrosis. CONCLUSION: Long UC duration and scarring background mucosa were predictors of severe submucosal fibrosis associated with perforation during ESD.

Impact of endoscopy intervals on metachronous gastric cancer after endoscopic submucosal dissection: Comparison between 1 year and half-a-year.

OBJECTIVES: Japanese guidelines recommend posttreatment endoscopy once or twice a year after endoscopic submucosal dissection (ESD) for early gastric cancer. However, the impact of endoscopy intervals on metachronous gastric cancer (MGC) remains unclear, especially the difference between 1-year and half-a-year intervals. We aimed to investigate this difference. METHODS: This study retrospectively investigated 2429 patients who underwent gastric ESD between May 2001 and June 2019 at our hospital. Patients who developed MGC were classified based on those who underwent the previous endoscopy within at least 7 months (short-interval group) and within 8-13 months (regular-interval group). Propensity score matching (PSM) was used to adjust for possible confounders. The primary outcome was the proportion of MGC beyond curative ESD criteria established in the guidelines. RESULTS: A total of 216 eligible patients developed MGC. The short- and regular-interval groups included 43 and 173 patients, respectively. Overall, no patients in the short-interval group had MGC beyond curative ESD criteria, while 27 patients in the regular-interval group did. The proportion of MGC beyond curative ESD criteria was significantly lower in the short-interval group than in the regular-interval group before (P = 0.003) and after (P = 0.028) PSM. Although not significant, the short-interval group tended to have a higher stomach preservation rate than the regular-interval group (P = 0.093). CONCLUSION: Our study indicated a possible benefit of biannual surveillance endoscopy in the early post-ESD period.

Endoscopic full-thickness resection vs. endoscopic submucosal dissection of residual/recurrent colonic lesions on scars: a retrospective Italian and Japanese comparative study.

BACKGROUND AND AIMS: Endoscopic treatment of recurrent/residual colonic lesions on scars is a challenging procedure. In this setting, endoscopic submucosal dissection (ESD) is considered the first choice, despite a significant rate of complications. Endoscopic full-thickness resection (eFTR) has been shown to be well-tolerated and effective for these lesions. The aim of this study is to conduct a comparison of outcomes for resection of such lesions between ESD and eFTR in an Italian and a Japanese referral center. METHODS: From January 2018 to July 2020, we retrospectively enrolled patients with residual/recurrent colonic lesions, 20 treated by eFTR in Italy and 43 treated by ESD in Japan. The primary outcome was to compare the two techniques in terms of en-bloc and R0-resection rates, whereas complications, time of procedure, and outcomes at 3-month follow-up were evaluated as secondary outcomes. RESULTS: R0 resection rate was not significantly different between the two groups [18/20 (90%) and 41/43 (95%); P= 0.66]. En-bloc resection was 100% in both groups. No significant difference was found in the procedure time (54 min vs. 61 min; P= 0.9). There was a higher perforation rate in the ESD group [11/43 (26%) vs. 0/20 (0%); P= 0.01]. At the 3-month follow-up, two lesions relapsed in the eFTR cohort and none in the ESD cohort (P= 0.1). CONCLUSION: eFTR is a safer, as effective and equally time-consuming technique compared with ESD for the treatment of residual/recurrent colonic lesions on scars and could become an alternative therapeutic option for such lesions.

Endoscopic full-thickness resection for gastric submucosal tumors: Japanese multicenter prospective study.

OBJECTIVES: Early gastric cancer endoscopic resection (ER) is prominent in Japan. However, evidence regarding ER of gastric submucosal tumors (SMT) is limited. This prospective multicenter phase II study investigated the efficacy and safety of endoscopic full-thickness resection (EFTR) for gastric SMT. METHODS: Endoscopic full-thickness resection indication for gastric SMT was 11-30 mm, histologically proven or clinically suspicious (irregular margin, increasing size, or internal heterogeneity) gastrointestinal stromal tumors (GIST), with no ulceration and intraluminal growth type. The primary end-point was the complete ER (ER0) rate, with a sample size of 42. RESULTS: We enrolled 46 patients with 46 lesions between September 2020 and May 2023 at seven Japanese institutions. The mean ± SD (range) endoscopic tumor size was 18.8 ± 4.5 (11-28) mm. The tumor resection and defect closure times were 54 ± 26 (22-125) min and 33 ± 28 (12-186) min, respectively. A 100% ER0 was achieved in all 46 patients. The EFTR procedure was accomplished in all patients without surgical intervention. One patient had delayed perforation and was managed endoscopically. GIST accounted for 76% (n = 35) of the cases. R0, R1, and RX rates were 33 (77%), 3 (6.5%), and 7 (15%), respectively. CONCLUSION: Endoscopic full-thickness resection for gastric SMT of 11-30 mm is efficacious. It warrants further validation in a large-scale cohort study to determine the long-term outcome of this treatment for patients with gastric GIST.

Endoscopic Resection with One-Port Placement: A Newly Developed Technique for the Safe Management of Advanced Endoscopic Resection for Gastric Gastrointestinal Stromal Tumors.

INTRODUCTION: Endoscopic full-thickness resection (EFTR) without laparoscopic assistance (pure EFTR) is an emerging, less invasive treatment for gastrointestinal stromal tumors (GISTs). However, the technique has seldom been performed outside China because of concerns regarding pneumoperitoneum, maintenance of endoscopic view, and endoscopic suturing. This study aimed to evaluate the efficacy and safety of endoscopic resection with one-port placement (EROPP) for gastric GISTs. METHODS: This retrospective study included 17 patients with gastric GISTs originating from the muscularis propria who underwent EROPP between 2019 and 2022. One camera port was inserted in the umbilicus before initiating the endoscopic procedure to maintain intra-abdominal pressure, which was monitored and adjusted via this port. While allowing for conversion to laparoscopic surgery if needed, EFTR was performed as follows: (1) circumferential incision of the mucosal and submucosal layers around the lesion was performed by typical endoscopic submucosal dissection; (2) an intentional perforation and subsequent seromuscular resection was made using dental floss and an endo-clip for traction; and (3) closure of the gastric full-thickness defect was performed with an over-the-scope clip (OTSC) after peroral retrieval of the specimen. We retrospectively assessed the short-term outcomes and safety. RESULTS: All procedures were completed successfully without conversion to laparoscopic surgery. The median size of the resected tumors was 23 mm (range, 8-35 mm), the median resection time was 36 min (range, 22-95 min), and closure time was 18 min (range, 10-45 min). The rates of en bloc and complete resection were 100% and 88%, respectively. In 2 cases, another port was added to aspirate the leaking fluid or check the condition of the endoscopic closure. All gastric defects were endoscopically closed, mainly using OTSCs. The recovery course for all patients was uneventful, and no adverse events were reported. CONCLUSIONS: EROPP is a safe and minimally invasive treatment for gastric GISTs and appears to be suitable for introducing EFTR procedures.

Serrated polyps in patients with ulcerative colitis: Unique clinicopathological and biological characteristics.

BACKGROUND: Serrated polyps have recently been reported in patients with ulcerative colitis (UC); however, their prevalence and detailed characteristics remain unclear. METHODS: The prevalence and clinicopathological and biological characteristics of serrated polyps in patients with UC were retrospectively examined in a single tertiary inflammatory bowel disease center in Japan from 2000 to 2020. RESULTS: Among 2035 patients with UC who underwent total colonoscopy, 252 neoplasms, including 36 serrated polyps (26 in colitis-affected segments, 10 in colitis-unaffected segments), were identified in 187 patients with UC. The proportion of serrated polyps was 1.8% (36/2035). Serrated polyps in colitis-affected segments were common with extensive colitis (88%), history of persistent active colitis (58%), and long UC duration (12.1 years). Serrated polyps in colitis-affected segments were more common in men (88%). Of the 26 serrated polyps in colitis-affected segments, 15, 6, and 5 were categorized as sessile serrated lesion-like dysplasia, traditional serrated adenoma-like dysplasia, and serrated dysplasia not otherwise specified, respectively. Sessile serrated lesion-like dysplasia was common in the proximal colon (67%) and with BRAF mutation (62%), whereas traditional serrated adenoma-like dysplasia and serrated dysplasia not otherwise specified were common in the distal colon (100% and 80%, respectively) and with KRAS mutations (100% and 75%, respectively). CONCLUSIONS: Serrated polyps comprised 14% of the neoplasias in patients with UC. Serrated polyps in colitis-affected segments were common in men with extensive and longstanding colitis, suggesting chronic inflammation in the development of serrated polyps in patients with UC.

Comparison of purse-string suture versus over-the-scope clip for gastric endoscopic full-thickness closure: traction and leak pressure testing in ex vivo porcine model.

BACKGROUND: The recently developed endoscopic full-thickness resection technique requires reliable closure. The main closure methods are the purse-string suture (PSS) technique and over-the-scope clip (OTSC) technique; however, basic data on the closure strength of each technique are lacking. This study was performed to compare the closure strengths of these two methods in an ex vivo porcine model. METHODS: In the traction test, a virtual 5-cm full-thickness closure line was closed by the following six methods three times each: conventional hemoclips, mucosal PSS, seromuscular PSS, mucosal OTSC, seromuscular OTSC, and surgical suture. The primary endpoint was the tension at the starting point of dehiscence, measured in Newtons (N) by an automatic traction machine. In the leak test, a 15-mm gastric full-thickness defect was closed by PSS or OTSC six times each, and the closed stomach was then pressurized in a water container. The primary endpoint was the leak pressure when air bubbles appeared. The secondary endpoints were the procedure time and presence of complete inverted closure. RESULTS: The mean tension was 2.16, 3.68, 5.15, 18.30, 19.30, and 62.40 N for conventional hemoclips, mucosal PSS, seromuscular PSS, mucosal OTSC, seromuscular OTSC, and surgical suture, respectively. Complete inverted closure was observed for seromuscular PSS, seromuscular OTSC, and surgical suture. The mean leak pressure was 13.7 and 24.8 mmHg in the PSS and OTSC group, respectively (P < 0.01). The mean procedure time was 541 and 169 s in the PSS and OTSC group, respectively (P < 0.01). Complete inverted closure was observed in OTSC alone. CONCLUSION: The OTSC, which allows complete inverted closure, showed greater closure strength than PSS. Considering the size limitation suitable for single OTSC, a therapeutic strategy for closing the larger size is further warranted.

Clinical factors associated with noncurative endoscopic submucosal dissection for the expanded indication of intestinal-type early gastric cancer: Post hoc analysis of a multi-institutional, single-arm, confirmatory trial (JCOG0607).

OBJECTIVES: The multi-institutional, single-arm, confirmatory trial JCOG0607 showed excellent efficacy of endoscopic submucosal dissection (ESD) for the expanded indication of intramucosal intestinal-type early gastric cancer (EGC), which consists of two groups: lesions >2 cm if clinical finding of ulcer (cUL)-negative, or those ≤3 cm if cUL-positive because of the expected low risk of lymph node metastasis. However, the proportion of noncurative resections (NCR) requiring additional surgery was high (32.4%). This post hoc analysis aimed to explore the clinical factors associated with NCR. METHODS: As the expanded indication includes two different groups, we explored the clinical factors associated with NCR separately in cUL-negative (>2 cm) and cUL-positive (≤3 cm) groups using the log-linear model. RESULTS: Two hundred and sixty cUL-negative and 206 cUL-positive EGCs were analyzed. The proportions of NCR were 33.8% in the cUL-negative group and 29.6% in the cUL-positive group. A multivariable analysis demonstrated that moderately differentiated predominant histology diagnosed in pretreatment biopsy (risk ratio [RR] 1.93, 95% confidence interval [CI] 1.34-2.77, P < 0.001) and lesion in the upper stomach (RR 1.75, 95% CI 1.03-2.96, P = 0.038) in the cUL-negative EGCs, and tumor size >2 cm (RR 1.78, 95% CI 1.22-2.58, P = 0.003) and female sex (RR 1.62, 95% CI 1.07-2.44, P = 0.021) in the cUL-positive EGCs were independent factors associated with NCR. CONCLUSIONS: Clinical risk factors associated with NCR were different between cUL-negative and cUL-positive EGCs. To avoid NCR, we need to take these factors into account when deciding expanded indications for ESD.

Long-term Survival After Endoscopic Resection For Gastric Cancer: Real-world Evidence From a Multicenter Prospective Cohort.

BACKGROUND & AIMS: We aimed to clarify the long-term outcomes of endoscopic resection (ER) for early gastric cancers (EGCs) based on pathological curability in a multicenter prospective cohort study. METHODS: We analyzed the long-term outcomes of 9054 patients with 10,021 EGCs undergoing ER between July 2010 and June 2012. Primary endpoint was the 5-year overall survival (OS). The hazard ratio for all-cause mortality was calculated using the Cox proportional hazards model. We also compared the 5-year OS with the expected one calculated for the surgically resected patients with EGC. If the lower limit of the 95% confidence interval (CI) of the 5-year OS exceeded the expected 5-year OS minus a margin of 5% (threshold 5-year OS), ER was considered to be effective. Pathological curability was categorized into en bloc resection, negative margins, and negative lymphovascular invasion: differentiated-type, pT1a, ulcer negative, ≤2 cm (Category A1); differentiated-type, pT1a, ulcer negative, >2 cm or ulcer positive, ≤3 cm (Category A2); undifferentiated-type, pT1a, ulcer negative, ≤2 cm (Category A3); differentiated-type, pT1b (SM1), ≤3 cm (Category B); or noncurative resections (Category C). RESULTS: Overall, the 5-year OS was 89.0% (95% CI, 88.3%-89.6%). In a multivariate analysis, no significant differences were observed when the hazard ratio of Categories A2, A3, and B were compared with that of A1. In all the pathological curability categories, the lower limit of the 95% CI for the 5-year OS exceeded the threshold 5-year OS. CONCLUSION: ER can be recommended as a standard treatment for patients with EGCs fulfilling Category A2, A3, and B, as well as A1 (UMIN Clinical Trial Registry, UMIN000005871).

Cervical esophageal adenocarcinoma of intestinal type in ectopic gastric mucosa.

A 45-year-old man underwent esophagogastroduodenoscopy because of symptoms of laryngopharyngeal discomfort. We found a protruded reddish lesion adjacent to the ectopic gastric mucosa (EGM) in the cervical esophagus, and a biopsy revealed that it was a tubular adenocarcinoma. We diagnosed the patient with intramucosal cancer and performed endoscopic submucosal dissection. Esophageal endoscopic submucosal dissection was performed under general anesthesia using a conventional procedure. The resected tumor measured 23 × 14 mm and was adjacent to the EGM. Histologically, the tumor cells showed moderately well-differentiated adenocarcinoma confined to the muscularis mucosa with no lymphovascular infiltration. Immunohistochemically, the tumor cells were positive for intestinal markers, namely MUC2 and CD10, and negative for gastric markers, namely MUC5AC and MUC6. The patient had no post-endoscopy submucosal dissection stenosis and remained disease-free without local recurrence. EGM of the cervical esophagus develops from the columnar epithelium during embryonic development. There are few reports on endoscopic submucosal dissection for mucosal cancer. Of these, immunostaining was performed in three cases. All were positive for MUC5AC and MUC6 and negative for MUC2 and CD10. Usually, EGM shows gastric type epithelium, but occasional cases with intestinal metaplasia, which show positivity for MUC2 and CD10, have been reported. Therefore, we consider this to be an extremely rare case of esophageal adenocarcinoma arising from intestinal metaplasia within the EGM.

Endoscopic resection is feasible for high-grade dysplasia in patients with ulcerative colitis.

BACKGROUND: Endoscopic resection (ER) is feasible for treating well-circumscribed dysplasia in patients with ulcerative colitis (UC). However, long-term prognosis of ER for high-grade dysplasia (HGD) in patients with UC remains unclear. We aimed to evaluate the long-term prognoses of ER for HGD compared with low-grade dysplasia (LGD) and verify the feasibility of ER and follow-up with surveillance colonoscopy for HGD. METHODS: An observational, single-center retrospective study included 38 and 22 patients with LGD and HGD who were followed-up with surveillance colonoscopy after ER. We evaluated the cumulative incidence rate of metachronous HGD or colorectal cancer (CRC) and identified the characteristics of metachronous dysplasia. RESULTS: The median follow-up period was 56 months, and surveillance colonoscopies were performed 3.6 times (mean). The 5-year cumulative incidence rate of HGD/CRC was relatively high in HGD (24.6%) than in LGD (13.7%), but the difference was not significant (p = .16). In HGD cases, six metachronous dysplasia lesions (two LGD and four HGD) were detected 11.6-40.5 months after ER. However, these patients did not progress to CRC. All metachronous lesions were well-circumscribed and with no invisible dysplasia surrounding them; they were 'endoscopically resectable' lesions. Two of the four metachronous HGD lesions were treated endoscopically and two, by colectomy. No synchronous HGD or CRC was detected in the colectomy specimens. CONCLUSIONS: Our results suggest that ER and follow-up with surveillance colonoscopy is feasible in patients with HGD when histological complete resection is achieved.

Endoscopic resection for gastric submucosal tumors: Japanese multicenter retrospective study.

OBJECTIVES: Limited information is available on the efficacy and safety of endoscopic resection (ER) of gastric submucosal tumors (SMTs) in Japanese endoscopic practice where ER for gastric tumors is extremely popular. METHODS: We conducted this study to elucidate the current scenario of ER for gastric SMTs in Japanese endoscopic practice. Patients (from 12 institutions) with gastric SMTs who underwent ER were enrolled from the first case until August 2020. RESULTS: We enrolled 117 patients with 118 lesions. The number of patients who underwent ER increased over the years. The mean endoscopic tumor size was 20 ± 7.2 (8-40) mm. The growth type was primarily intraluminal (90%). The mean resection and wound closure times were 58 ± 38 (range, 12-254) min and 31 ± 41 (range, 3-330) min, respectively. Complete ER was achieved for 117 (99%) lesions. Full-thickness resection rate was 44%; however, only 12 (10%) patients required abdominal paracentesis for decompression. Endoscopic treatments were completed in 115 (97%) lesions, while three lesions required conversions to laparoscopic surgery due to luminal collapse, uncontrolled bleeding, and difficulty in defect closure. Gastrointestinal stromal tumors were the most common pathology (74%). No recurrence was observed during the mean follow-up period of 4.3 ± 2.9 years. The 5-year overall survival rate was 98.9% (95% confidence interval 97.8-100%). CONCLUSION: Performance of ER for gastric SMTs is increasing in Japan. The technique seems feasible in Japanese endoscopic practice, warranting further validation in a prospective study.

Comparison of treatment outcomes between endoscopic submucosal dissection with the needle-type knife and insulated-tip knife for superficial esophageal neoplasms.

Our study aimed to compare the treatment outcomes between endoscopic submucosal dissection (ESD) with an insulated-tip knife (ESD-IT) and a needle-type knife (ESD-N) for large superficial esophageal neoplasms, as no study of this kind has been previously reported. We used the dataset of a multicenter, randomized controlled trial that compared conventional ESD (C-ESD) and traction-assisted ESD (TA-ESD) for superficial esophageal neoplasms. We compared the procedural outcomes between ESD-IT and ESD-N in a post hoc analysis and conducted sub-analyses based on traction assistance and electrical knife type. We included 223 (EST-IT, n = 169; ESD-N, n = 54) patients with no significant differences in baseline characteristics. The operator handover rate due to ESD difficulties was significantly higher in ESD-N (ESD-IT = 0.6% vs. ESD-N = 13.0%, P = 0.001), while the injection volume was significantly higher in ESD-IT than in ESD-N (40.0 vs. 20.5 mL, P < 0.001). Other outcomes were comparable between both groups (procedural time: 51.0 vs. 49.5 minute, P = 0.89; complete resection: 90.5% vs. 90.7%, P > 0.99; and complication rate: 1.8% vs. 3.7%, P = 0.60 for ESD-IT and ESD-N, respectively). In the sub-analyses, the handover rate was significantly lower with TA-ESD than with C-ESD for ESD-N (3.2% vs. 26.1%, P = 0.034), and a significantly smaller injection volume was used in TA-ESD than in C-ESD for ESD-IT (31.5 vs. 47.0 mL, P < 0.01). ESD with either endoscopic device achieved favorable treatment outcomes with low complication rates. The handover rate in ESD-N and the injection volume in ESD-IT improved with the traction method.

Learning curve analysis for duodenal endoscopic submucosal dissection: A single-operator experience.

BACKGROUND AND AIMS: Superficial duodenal epithelial tumors are emerging targets for endoscopic submucosal dissection (ESD). However, it is unknown how competence is achieved in duodenal ESD. This study aimed to elucidate the learning curve for duodenal ESD. METHODS: This retrospective observational study included 100 consecutive patients who underwent duodenal ESD by a single endoscopist between March 2014 and September 2021. The primary outcome was to define the learning curve for duodenal ESD by an endoscopist with sufficient non-duodenal ESD experience. Cumulative sum (CUSUM) curve analysis was used to assess the learning curve in terms of procedural speed. Comparative analyses of phases identified using the CUSUM method were performed. RESULTS: In total, 98 patients were included in the analysis. Evaluation of the cumulative sum curve revealed four distinct phases in the graph: phase I, cases 1-25 (learning phase); phase II, cases 26-47 (proficiency phase); phase III, cases 48-72 (mastery phase); and phase IV, cases 73-98 (after introduction of general anesthesia). The median procedural speed was significantly faster in phase II than in phase I (11.1 mm2 /min vs 7.0 mm2 /min, P = .002). Clinically significant intraoperative perforation tended to decrease through phase II to phase IV (22.7%, 12.0%, and 3.8% in phases II, III, and IV, respectively). Delayed perforation occurred only in phases I and II. CONCLUSIONS: Duodenal ESD requires 25 cases to gain proficiency and 50 to achieve mastery even for an endoscopist with extensive non-duodenal ESD experience.