Comparison of Effective Imaging Modalities for Detecting Gastric Neoplasms: A Randomized 3-Arm Phase II Trial.

INTRODUCTION: The early detection of gastric neoplasms (GNs) leads to favorable treatment outcomes. The latest endoscopic system, EVIS X1, includes third-generation narrow-band imaging (3G-NBI), texture and color enhancement imaging (TXI), and high-definition white-light imaging (WLI). Therefore, this randomized phase II trial aimed to identify the most promising imaging modality for GN detection using 3G-NBI and TXI. METHODS: Patients with scheduled surveillance endoscopy after a history of esophageal cancer or GN or preoperative endoscopy for known esophageal cancer or GN were randomly assigned to the 3G-NBI, TXI, or WLI groups. Endoscopic observations were performed to detect new GN lesions, and all suspected lesions were biopsied. The primary endpoint was the GN detection rate during primary observation. Secondary endpoints were the rate of missed GNs, early gastric cancer detection rate, and positive predictive value for a GN diagnosis. The decision rule had a higher GN detection rate between 3G-NBI and TXI, outperforming WLI by >1.0%. RESULTS: Finally, 901 patients were enrolled and assigned to the 3G-NBI, TXI, and WLI groups (300, 300, and 301 patients, respectively). GN detection rates in the 3G-NBI, TXI, and WLI groups were 7.3, 5.0, and 5.6%, respectively. The rates of missed GNs were 1.0, 0.7, and 1.0%, the detection rates of early gastric cancer were 5.7, 4.0, and 5.6%, and the positive predictive values for the diagnosis of GN were 36.5, 21.3, and 36.8% in the 3G-NBI, TXI, and WLI groups, respectively. DISCUSSION: Compared with TXI and WLI, 3G-NBI is a more promising modality for GN detection.

Prospective multicenter trial of the cryoballoon ablation system for superficial esophageal squamous cell carcinoma on the post-endoscopic resection scar. A CRYO-SCAR study (EPOC1902).

BACKGROUND AND AIMS: Endoscopic resection (ER) is a minimally invasive treatment for superficial esophageal squamous cell carcinoma (SESCC). Post-ER scars complicate en bloc resection, even with advanced techniques, such as endoscopic submucosal dissection. The cryoballoon ablation system (CBAS) effectively manages Barrett's esophagus but has limited evidence in SESCC treatment, particularly on post-ER scars. This study aimed to evaluate the efficacy and safety of the CBAS for treating SESCC on post-ER scars. METHODS: This prospective study was conducted at two tertiary referral centers in Japan in patients endoscopically diagnosed with T1a SESCC on the post-ER scar. Focal CBAS was used for cryoablation, with specific criteria for lesion selection and treatment method. The primary endpoint was local complete response (L-CR) rate of the primary lesion 48 weeks after the first cryoablation as evaluated by an independent central evaluation committee. RESULTS: From October 2020 to October 2021, 15 patients with 17 lesions underwent cryoablation, with two requiring repeat cryoablation. The L-CR rate for primary and all lesions evaluated by the central evaluation committee was 100%. The endoscopist's evaluation was consistent with these results. The median procedure time was 9 min. Eight patients experienced no pain, and the highest pain score reported on a numeric 1-10 rating scale was 3. The technical success rate was 94.7% (18/19). Throughout the median follow-up period of 14.3 months, recurrences, deaths, or severe treatment-related adverse events were not reported. CONCLUSIONS: CBAS is a potentially safe and effective approach for SESCC on post-ER scars and represents an encouraging alternative to traditional endoscopic treatments.

Outcomes of repeated endoscopic submucosal dissection for superficial Esophageal squamous cell carcinoma on endoscopic resection scar.

BACKGROUND: Endoscopic submucosal dissection (ESD) can be performed for superficial esophageal cancer. However, performing ESD for superficial esophageal cancer on a previous endoscopic resection scar may be difficult. METHODS: We compared the outcomes between ESD for superficial esophageal cancers on previous endoscopic resection scar (group A) and that for naïve lesions (group B). The study included outcomes of ESD, cumulative incidence of local failure, and predictors of the occurrence of local failure in ESD patients with squamous cell carcinoma (SCC). The outcome variables evaluated were en bloc resection rates, procedure times, adverse events, and overall survival rates. RESULTS: Overall, 220 lesions were extracted (groups A and B: 23 and 197 lesions, respectively). In groups A and B, the complete resection rates were 60.9 and 92.9% (P < 0.001), and the mean procedure times were 79 and 68 min (P = 0.15), respectively. The perforation rates in groups A and B were 4.3 and 1% (P = 0.28). The 1-year cumulative local failure rates were 22 and 1% (P < 0.001), respectively. In the multivariate Cox proportional hazards analysis, superficial esophageal SCC on a previous endoscopic resection scar was a strong predictor of local failure (hazard ratio = 21.95 [3.99-120.80], P < 0.001). The 3-year overall survival rates in groups A and B were 95 and 93% (P = 0.99), respectively. CONCLUSIONS: Repeated ESD on scar is an option for treating superficial esophageal SCC with an acceptable rate of adverse events. Because of the low complete resection rate and high local failure compared with conventional ESD, strict endoscopic follow-up is required after repeated esophageal ESD.

Remarkable response as a new indicator for endoscopic evaluation of local efficacy of non-surgical treatments for esophageal cancer.

In Japan, standard of care of the patients with resectable esophageal cancer is neoadjuvant chemotherapy (NAC) followed by esophagectomy. Patients unfitted for surgery or with unresectable locally advanced esophageal cancer are generally indicated with definitive chemoradiotherapy (CRT). Local disease control is undoubtful important for the management of patients with esophageal cancer, therefore endoscopic evaluation of local efficacy after non-surgical treatments must be essential. The significant shrink of primary site after NAC has been reported as a good indicator of pathological good response as well as favorable survival outcome after esophagectomy. And patients who could achieve remarkable shrink to T1 level after CRT had favorable outcomes with salvage surgery and could be good candidates for salvage endoscopic treatments. Based on these data, "Japanese Classification of Esophageal Cancer, 12th edition" defined the new endoscopic criteria "remarkable response (RR)", that means significant volume reduction after treatment, with the subjective endoscopic evaluation are proposed. In addition, the finding of local recurrence (LR) at primary site after achieving a CR was also proposed in the latest edition of Japanese Classification of Esophageal Cancer. The findings of LR are also important for detecting candidates for salvage endoscopic treatments at an early timing during surveillance after CRT. The endoscopic evaluation would encourage us to make concrete decisions for further treatment indications, therefore physicians treating patients with esophageal cancer should be well-acquainted with each finding.

Evaluating the usefulness of considering the size and morphological type of type B2 vessel area based on Japan Esophageal Society classification in estimating tumor invasion depth in superficial esophageal squamous cell carcinomas: study protocol for a prospective observational study (Japan BEES study).

BACKGROUND: Accurate evaluation of tumor invasion depth is essential to determine the appropriate treatment strategy for patients with superficial esophageal cancer. The pretreatment tumor depth diagnosis currently relies on the magnifying endoscopic classification established by the Japan Esophageal Society (JES). However, the diagnostic accuracy of tumors involving the muscularis mucosa (MM) or those invading the upper third of the submucosal layer (SM1), which correspond to Type B2 vessels in the JES classification, remains insufficient. Previous retrospective studies have reported improved accuracy by considering additional findings, such as the size and macroscopic type of the Type B2 vessel area, in evaluating tumor invasion depth. Therefore, this study aimed to investigate whether incorporating the size and/or macroscopic type of the Type B2 vessel area improves the diagnostic accuracy of preoperative tumor invasion depth prediction based on the JES classification. METHODS: This multicenter prospective observational study will include patients diagnosed with MM/SM1 esophageal squamous cell carcinoma based on the Type B2 vessels of the JES classification. The tumor invasion depth will be evaluated using both the standard JES classification (standard-depth evaluation) and the JES classification with additional findings (hypothetical-depth evaluation) for the same set of patients. Data from both endoscopic depth evaluations will be electronically collected and stored in a cloud-based database before endoscopic resection or esophagectomy. This study's primary endpoint is accuracy, defined as the proportion of cases in which the preoperative depth diagnosis matched the histological depth diagnosis after resection. Outcomes of standard- and hypothetical-depth evaluation will be compared. DISCUSSION: Collecting reliable prospective data on the JES classification, explicitly concerning the B2 vessel category, has the potential to provide valuable insights. Incorporating additional findings into the in-depth evaluation process may guide clinical decision-making and promote evidence-based medicine practices in managing superficial esophageal cancer. TRIAL REGISTRATION: This trial was registered in the Clinical Trials Registry of the University Hospital Medical Information Network (UMIN-CTR) under the identifier UMIN000051145, registered on 23/5/2023.

A phase III randomized controlled trial comparing local field with additional prophylactic irradiation in chemoradiotherapy for clinical-T1bN0M0 esophageal cancer: ARMADILLO trial (JCOG1904).

Chemoradiotherapy has been considered as one of the standard treatment options for clinical T1bN0M0 esophageal squamous cell carcinoma with organ preservation. However, 20% of patients develop locoregional recurrence after chemoradiotherapy, which requires salvage treatment including salvage surgery and endoscopic resection. Salvage surgery can cause complications and treatment-related death. Interestingly, chemoradiotherapy with elective nodal irradiation has been reported to reduce the locoregional recurrence of advanced esophageal squamous cell carcinoma. Hence, we are conducting a clinical trial to confirm whether modified chemoradiotherapy with elective nodal irradiation was superiority to that without elective nodal irradiation for the patients with cT1bN0M0 esophageal squamous cell carcinoma. The primary endpoint is major progression-free survival, defined as the time from randomization to the date of death or disease progression, excluding successful curative resection through salvage endoscopic resection. We plan to enroll 280 patients from 54 institutions over 4 years. This trial has been registered in the Japan Registry of Clinical Trials (jRCTs031200067).

Investigation of vertical margin involvement in endoscopic resection for T1 colorectal cancer.

OBJECTIVES: The resection of vertical margin-negative submucosally invasive colorectal cancer (CRC) relies on the pathological risk assessment of lymph node metastasis. However, no large-scale study has clarified the endoscopic resection (ER) outcome for submucosally invasive CRC, focusing on the vertical margin status. This retrospective study aimed to examine vertical margin involvement in ER for submucosally invasive CRC and explore the treatment consequences associated with vertical margin status. METHODS: We analyzed 395 submucosally invasive CRC cases in 389 patients who underwent ER at our hospital between 2008 and 2020. The presence of residual tumors and simultaneous lymph node metastasis in patients who underwent additional surgery was assessed and compared between the vertical incomplete ER and the vertical margin-negative groups. RESULTS: Among the patients, 270 were men, with a median age of 69 years. The vertical incomplete ER rate was 21.5%, with positive vertical margins and unclear vertical margins identified in 12.2% and 9.3% of the cases, respectively. Among 154 patients who underwent additional surgery after ER, the vertical incomplete ER group had a significantly higher residual tumor rate than the vertical margin-negative group (P = 0.001). The vertical incomplete ER group had a significantly higher lymph node metastasis rate than the vertical margin-negative group (P = 0.029). CONCLUSION: This study clarified the substantial risk of vertical incomplete ER in submucosally invasive CRC and revealed the high risk of residual tumor and lymph node metastasis in vertical incomplete ER for submucosal CRC.

Evaluating the identification of the extent of gastric cancer by over-1000 nm near-infrared hyperspectral imaging using surgical specimens.

Significance: Determining the extent of gastric cancer (GC) is necessary for evaluating the gastrectomy margin for GC. Additionally, determining the extent of the GC that is not exposed to the mucosal surface remains difficult. However, near-infrared (NIR) can penetrate mucosal tissues highly efficiently. Aim: We investigated the ability of near-infrared hyperspectral imaging (NIR-HSI) to identify GC areas, including exposed and unexposed using surgical specimens, and explored the identifiable characteristics of the GC. Approach: Our study examined 10 patients with diagnosed GC who underwent surgery between 2020 and 2021. Specimen images were captured using NIR-HSI. For the specimens, the exposed area was defined as an area wherein the cancer was exposed on the surface, the unexposed area as an area wherein the cancer was present although the surface was covered by normal tissue, and the normal area as an area wherein the cancer was absent. We estimated the GC (including the exposed and unexposed areas) and normal areas using a support vector machine, which is a machine-learning method for classification. The prediction accuracy of the GC region in every area and normal region was evaluated. Additionally, the tumor thicknesses of the GC were pathologically measured, and their differences in identifiable and unidentifiable areas were compared using NIR-HSI. Results: The average prediction accuracy of the GC regions combined with both areas was 77.2%; with exposed and unexposed areas was 79.7% and 68.5%, respectively; and with normal regions was 79.7%. Additionally, the areas identified as cancerous had a tumor thickness of >2 mm. Conclusions: NIR-HSI identified the GC regions with high rates. As a feature, the exposed and unexposed areas with tumor thicknesses of >2 mm were identified using NIR-HSI.

Efficacy of a novel self-assembling peptide gel for hemostasis in refractory neoplastic bleeding.

Video 1Outline of how self-assembling peptide gel can be used ex vivo.

Hot snare polypectomy vs endoscopic mucosal resection using bipolar snare for intermediate size colorectal lesions: Propensity score matching.

BACKGROUND: Endoscopic resection (ER) with bipolar snare, in which the electric current only passes through the tissue between the device's two electrodes, is a prominent method used to prevent perforation due to electricity potentially. ER using bipolar snare with or without submucosal injection enabled safe resection of colorectal lesions measuring 10-15 mm in an ex vivo porcine model. ER with bipolar snare is expected to have good treatment outcomes in 10-15 mm colorectal lesions, with high safety even without submucosal injection. However, no clinical reports have compared treatment outcomes with and without submucosal injection. AIM: To compare the treatment outcomes of bipolar polypectomy with hot snare polypectomy (HSP) to those with endoscopic mucosal resection (EMR). METHODS: In this single-centre retrospective study, we enrolled 10-15 mm nonpedunculated colorectal lesions (565 Lesions in 463 patients) diagnosed as type 2A based on the Japan Narrow-band Imaging Expert Team classification, resected by either HSP or EMR between January 2018 and June 2021 at the National Cancer Center Hospital East. Lesions were divided into HSP and EMR groups, and propensity score matching was performed. In the matched cohort, en bloc and R0 resection rates and adverse events were compared between the two groups. RESULTS: Of the 565 lesions in 463 patients, 117 lesions each in the HSP and EMR groups were selected after propensity score matching. In the original cohort, there was a significant difference in antithrombotic drug use (P < 0.05), lesion size (P < 0.01), location (P < 0.01), and macroscopic type (P < 0.05) between the HSP and EMR groups. In the matched cohort, the en bloc resection rates were comparable between both groups [93.2% (109/117) vs 92.3% (108/117), P = 0.81], and there was no significant difference in the R0 resection rate [77.8% (91/117) vs 80.3% (94/117), P = 0.64]. The incidence of delayed bleeding was similar in both groups [1.7% (2/117)]. Perforation occurred in the EMR group [0.9% (1/117)] but not in the HSP group. CONCLUSION: Using bipolar snare, ER of nonpedunculated 10-15 mm colorectal lesions may be performed safely and effectively, even without submucosal injection.

Clinical outcome of endoscopic-assisted transoral surgery for superficial cancer of pharyngo-esophageal junction.

BACKGROUND: Endoscopic-assisted transoral surgery (TOS) for superficial cancer of the pharyngo-esophageal junction (PEJ) is risk of stricture, and therapeutic outcomes are unclear. This study aimed to evaluate clinical outcomes of endoscopic-assisted TOS for superficial PEJ cancers. METHODS: We retrospectively compared clinical outcomes of endoscopic-assisted TOS for superficial PEJ cancers (group A) and of other sites in the hypopharynx (group B). RESULTS: The group A comprised 12 lesions in 12 patients, and group B comprised 198 lesions in 146 patients. Group A and group B exhibited en bloc resection rates of 100% and 99%. Median operative times were 82 and 37 min (p < 0.001). The frequency of stricture and local recurrence in group A was significantly higher in group B (42% vs. 1%, p < 0.001; 25% vs. 6%, p = 0.036). All adverse events could be managed with conservative treatments. CONCLUSIONS: Endoscopic-assisted TOS is not ideal for treating superficial PEJ cancers compared to other sites.

Efficacy and safety of repeated endoscopic radial incision and cutting procedure for benign esophageal stricture.

Background and study aims: Radial incision and cutting (RIC) is indicated for refractory benign esophageal strictures after curative treatment for esophageal cancer and has shown favorable short-term outcomes. However, re-stricture after RIC may occur in the long term, and RIC is performed repeatedly in such cases, but the efficacy and safety of repeated RIC are unclear. Therefore, we aimed to demonstrate the efficacy and safety of the repeated RIC for refractory benign esophageal strictures after surgical and non-surgical treatment. Patients and methods: Between April 2008 and September 2019, we enrolled patients who were treated with the first RIC for benign esophageal strictures. The RIC was indicated for the refractory stricture and repeatedly performed for re-refractory esophageal stricture after RIC. We retrospectively evaluated the 6-month refractory stricture-free rate, and adverse events (AEs) in the first RIC and repeated RICs. Results: Forty-six patients (39 men, 7 women; median age, 71 years, range 49-85) were included. RIC was performed once in 24 patients (non-repeated RIC group) and two or more times in 22 patients (repeated RIC group). In all patients, the 6-month refractory stricture-free rate after the first RIC were 42.3 %. In the repeated RIC group, the 6-month refractory stricture-free rate after the first and repeated RICs were 18.2 % vs 18.2 %, respectively. No AEs were noted. Conclusions: Repeated RIC could be effective in the short-term and safe even for patients with refractory benign esophageal stricture after the first RIC. However, it cannot be considered curative treatment for refractory stricture because of poor long-term results.

Multi-institutional questionnaire on treatment strategies for superficial entire circumferential esophageal squamous cell carcinoma.

Objectives: Recent innovations in prophylactic treatment with steroids have overcome the issue of esophageal stricture after endoscopic submucosal dissection (ESD), except in entire circumferential esophageal squamous cell carcinoma (EC-ESCC). Current Japanese guidelines weakly recommend performing ESD for clinical epithelial/lamina propria EC-ESCC with a longitudinal extension <50 mm upon implementing prophylactic treatment against stricture. However, the accurate indications for ESD in EC-ESCC remain unknown, and strategies differ among institutions. The aim of this study was to understand the initial treatment strategy for EC-ESCC and prophylactic treatment after ESD against esophageal stricture. Methods: A questionnaire survey was conducted across 16 Japanese high-volume centers on the initial treatment for EC-ESCC according to the invasion depth and longitudinal extension, and prophylactic treatment against stricture. Results: ESD was performed as the initial treatment not only in clinical epithelial/lamina propria lesions <50 mm (88-94% of institutions), but also in clinical epithelial/lamina propria ≥50 mm (44-50% of institutions) and clinical muscularis mucosae/SM1 (submucosal invasion depth invasion within 200 µm) lesions <50 mm (56-75% of institutions). Regarding prophylactic treatment against esophageal stricture, although there was a common point of local steroid injection, the details and administration of other treatments varied among institutions. Conclusions: As ESD was performed with expanded indications for EC-ESCC than those recommended by the guidelines in more than half of the institutions, the validity of ESD for expanded EC-ESCC needs to be clarified. For that, it is necessary to prospectively collect short- and long-term outcomes after ESD and other treatments, including esophagectomy or chemoradiotherapy.

Usefulness of endoscopic ultrasound in predicting treatment efficacy of salvage endoscopic therapy for local failure after chemoradiotherapy for esophageal squamous cell carcinoma.

BACKGROUND: Salvage endoscopic therapy, including endoscopic resection (ER) and photodynamic therapy (PDT), is effective for esophageal squamous cell carcinoma (ESCC) in local failure after chemoradiotherapy (CRT). Resection with pathologically vertical margin-negative (VM0) for ER and local complete response (L-CR) for PDT are important surrogate prognostic markers for each therapy's efficacy. We aimed to evaluate the usefulness of endoscopic ultrasound (EUS) in predicting the efficacy of salvage endoscopic therapy in local failure after CRT for ESCC. METHODS: We included patients who underwent EUS followed by ER or PDT for local failure after CRT or radiotherapy for ESCC from 2006 to 2020. We evaluated EUS findings associated with VM0 resection for ER and L-CR for PDT, which included the status of the outermost part of the submucosal layer, tumor thickness, and tumor invasion length into the muscularis propria (MP) layer. RESULTS: Thirty and 47 patients were enrolled into the ER and PDT groups, respectively. The VM0 resection rate in the ER group was 87% (26/30). The EUS findings associated with VM0 resection were tumor thickness < 2.3 mm (p = 0.01) and preserved hyperechoic line of the outermost part of the submucosa layer (p < 0.01). The L-CR rate in the PDT group was 69% (32/47). The EUS findings associated with L-CR were tumor thickness < 5.0 mm (p < 0.01) and tumor invasion length into the MP layer < 1.6 mm (p = 0.03). CONCLUSIONS: EUS can be useful in predicting the efficacy of salvage endoscopic treatment for local failure after CRT for ESCC.

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.

Prospective study on the risk of transmission due to droplets and aerosols during an endoscopic procedure and the usefulness of extraoral suction devices.

OBJECTIVES: Endoscopy poses a high risk of severe acute respiratory syndrome coronavirus 2 infection for medical personnel due to the dispersal of aerosols from the patient. We investigated the location and size of droplets generated during esophagogastroduodenoscopy (EGD) and endoscopic submucosal dissection (ESD), the contamination of the surrounding area before and after the procedures, and the effectiveness of using an extraoral suction device (Free arm arteo; TOKYO GIKEN, Inc., Tokyo, Japan). METHODS: Patients who consented to the study and underwent EGD or ESD between December 8, 2020, and April 15, 2021, at the National Cancer Center East Hospital were included. Adenosine triphosphate (ATP) hygiene monitoring tests and a particle counter were used for measurements. RESULTS: Assessments were performed on 22 EGD and 15 ESD cases. ATP hygiene monitoring tests showed significant elevations at three sites near the patient, and two sites 1.5 m away, for EGD, and at four sites near the patient and 1.5 m away for ESD. In both ESD and EGD, extraoral suction devices reduced the extent of the contamination. Particles <5 µm in size were generated during endoscopic procedures and dispersed from both the forceps hole and the patient's mouth. The extraoral suction device did not reduce the number of particles generated. CONCLUSIONS: During endoscopic procedures, cleaning the surrounding environment is important in addition to standard precautions the endoscopist and caregivers take. The use of extraoral suction devices can also potentially reduce contamination of the surrounding environment.

Endoscopic management of familial adenomatous polyposis targeting colorectal lesions greater than 5 mm in size: a single-center retrospective study.

Preserving the colon while preventing colorectal cancer is challenging in patients with familial adenomatous polyposis. Although prophylactic colectomy is the current standard of care, some patients with familial adenomatous polyposis may wish to postpone colectomy as long as polyposis can be managed by endoscopic resection. This study examined our endoscopic management and prognostic results for patients with familial adenomatous polyposis who refused to undergo colectomy. We retrospectively analyzed the data of 12 patients with familial adenomatous polyposis treated at our hospital between January 1995 and December 2020. All patients opted to postpone prophylactic colectomy although they had significant polyp burdens and underwent endoscopic management, in which colorectal polyps sized > 5 mm were thoroughly resected during baseline colonoscopies and subsequently, newly arising colorectal polyps sized > 5 mm were periodically resected during surveillance colonoscopies. Patients (median age, 33 years) were followed up for a median of 5.2 years. The median number of colonoscopies and resected lesions per patient was 2 and 14 at baseline as well as, 9 and 32 during surveillance, respectively. The interval between colonoscopies was 1.0 and 7.0 months for baseline and surveillance, respectively. The colons of all 12 patients were preserved, and no invasive colorectal cancer developed. In 10 patients, 35 cases of high-grade dysplasia were observed and managed by endoscopic resection. Repeated endoscopic resection of colorectal polyps sized > 5 mm with appropriate surveillance may be an alternative form of endoscopic management for patients with familial adenomatous polyposis wishing to postpone colectomy.

Development of new gastric endoscopic submucosal dissection training model: A reproducibility evaluation study.

Background and study aims Gastric endoscopic submucosal dissection (ESD) is a highly technical procedure mainly due to the distinctive shape of the stomach and diverse locations of lesions. We developed a new gastric ESD training model (G-Master) that could accurately recreate the location of the stomach and assessed the reproducibility of located lesions in the model. Methods The model comprises a simulated mucous membrane sheet made of konjac flour and a setting frame, which can simulate 11 locations of the stomach. We assessed the reproducibility of each location in the model by assessing the procedure speed and using a questionnaire that was distributed among experts. In the questionnaire, each location was scored on a six-point scale for similarity of locations. Results The mean score for all locations was high with > 4 points. Regarding locations, lower anterior and posterior walls had medium scores with 3 to 4 points. The procedure speed was slower in the greater curvature of the upper and middle gastric portions, where ESD is considered more difficult than the overall procedure speed. Conclusions The new gastric ESD training model appears to be highly reproducible for each gastric location and its application for training in assuming actual gastric ESD locations.