Efficacy of endoscopic surveillance for pharyngeal mucosa during endoscopic resection for pharyngeal carcinoma: a multicenter prospective study.

INTRODUCTION: Since patients with pharyngeal squamous cell carcinoma (SCC) often have multiple pharyngeal lesions, evaluation of pharyngeal lesions before endoscopic resection (ER) is important. However, detailed endoscopic observation of the entire pharyngeal mucosa under conscious sedation is difficult. We examined the usefulness of endoscopic surveillance with narrow band imaging (NBI) and lugol staining for detection of pharyngeal sublesions during ER for pharyngeal SCC under general anesthesia (endoscopic surveillance during treatment; ESDT). METHODS: From January 2021 through June 2022, we examined 78 patients who were diagnosed with superficial pharyngeal SCC and underwent ER. They underwent the ESDT and for patients who were diagnosed with new lesions of pharyngeal SCC or high-grade dysplasia (HGD) that were not detected in the endoscopic examination before treatment, ER were performed simultaneously for new lesions and the main lesions. The primary endpoint of this study was the detection rate of new lesions of pharyngeal SCC or HGD in the ESDT. RESULTS: Fifteen of the 78 patients were diagnosed as having undetected new pharyngeal lesions in the ESDT and 10 (12.8%) (95% CI 6.9-22.2%) were histopathologically confirmed to have new lesions of pharyngeal SCC or HGD. Among the 13 lesions of SCC or HGD, 8 were found by NBI observation; however, 5 were undetectable using NBI but detectable by lugol staining. All of the 13 lesions had endoscopic findings of pink color sign on lugol staining. CONCLUSIONS: Endoscopic surveillance for pharyngeal sublesions during ER for pharyngeal SCC is feasible and useful.

Texture and color enhancement imaging improves the visibility of gastric neoplasms: clinical trial with image catalogue assessment using conventional and newly developed endoscopes.

BACKGROUND: Texture and color enhancement imaging (TXI) enhances the changes in endoscopic features caused by gastric neoplasms, such as redness/whiteness and elevation/depression. This study aimed to demonstrate the effectiveness of TXI in improving the visibility of gastric neoplasms compared with white light imaging (WLI) using conventional (CE) and newly developed endoscopes (NE). METHODS: We recruited patients who were histologically diagnosed with gastric neoplasms; endoscopy was performed, and gastric neoplasms photographed using three imaging modalities, including WLI, TXI mode 1 (TXI-1) and TXI mode 2 (TXI-2). Two different endoscopes (CE and NE) were used for the same patients. Six endoscopists provided the visibility scale scores ranging from 1 (poor) to 4 (excellent) for gastric neoplasms. The primary outcome was the visibility scale scores based on each modality and endoscope. The secondary outcome was the identification of factors including H. pylori infection, atrophy, location, size, morphology, histological diagnosis and intestinal metaplasia that affect the differences in visibility scale scores between TXI-1/TXI-2 and WLI. RESULTS: Fifty-two gastric neoplasms were analyzed. The mean visibility scale scores with the NE were 2.79 ± 1.07, 3.23 ± 0.96 and 3.14 ± 0.92 for WLI, TXI-1 and TXI-2, respectively. The mean visibility scales with the CE were 2.53 ± 1.10, 3.04 ± 1.05 and 2.96 ± 1.92 for WLI, TXI-1 and TXI-2, respectively. For both endoscopes, significant differences were observed in visibility scale scores between WLI and TXI-1 (p < 0.001) and between WLI and TXI-2 (p < 0.001). The visibility scale scores of NE were superior to those of CE in all modalities. In the secondary outcome, there was no factor affected the differences of visibility scale scores between TXI-1/TXI-2 and WLI. CONCLUSIONS: This study demonstrated that TXI-1 and TXI-2 enhanced the visibility scale scores of gastric neoplasms compared with that of WLI. Moreover, newly developed endoscope has the potential to improve visibility compared to conventional endoscope. TRIAL REGISTRATION: This study was registered with the University Hospital Medical Information Network (UMIN000042429, 16/11/2020).

Endoscopic Submucosal Dissection Facilitating Techniques Among Non-experts: A Systematic Literature Review.

BACKGROUND AND AIMS: The dissemination of endoscopic submucosal dissection (ESD) has been limited by its technical complexity and safety profile, particularly among non-experts. Various techniques and devices have facilitated the performance of ESD, but their yield and role in the path to learning ESD remain unclear. METHODS: We performed a systematic review by querying MEDLINE, EMBASE, Web of Science, and Japan Medical Abstracts Society specifically for comparative studies investigating the impact of assigned ESD techniques vs. conventional techniques among non-experts in ESD (< 50 ESD procedures). Procedural outcomes of efficacy, efficiency, and safety were assessed. RESULTS: We identified 46 studies evaluating 54 cohorts in which a total 237 non-experts performed 2461 ESDs conventionally, and 1953 ESDs using an assigned ESD technique (knives, countertraction, miscellaneous techniques). The majority of studies were from East Asia (67%), single-center (96%), observational in design (61%), in an animal model (57%), and gastric location (63%). The most studied techniques were countertraction techniques (48% cohorts) and scissor knives (15% cohorts), both of which commonly enhanced efficiency of ESD, and less so efficacy or safety. Techniques found to be beneficial in experts were more likely to be beneficial in non-experts (70% concordance) than vice versa (47% concordance). CONCLUSION: Based on the currently available literature, countertraction techniques and scissor knives should be considered for early incorporation into ESD training by non-experts. Several aspects of ESD training remain understudied, including techniques in Western non-experts, educational resources, and several commonly cited techniques. These areas should guide future investigation to enhance the pathway to learning ESD.

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.

Multi-loop traction device facilitates gastric endoscopic submucosal dissection: ex vivo pilot study and an inaugural clinical experience.

BACKGROUND: Endoscopic submucosal dissection (ESD) is technically difficult and requires considerable training. The authors have developed a multi-loop traction device (MLTD), a new traction device that offers easy attachment and detachment. We aimed to evaluate the utility of MLTD in ESD. METHODS: This ex vivo pilot study was a prospective, block-randomized, comparative study of a porcine stomach model. Twenty-four lesions were assigned to a group that undertook ESD using the MLTD (M-ESD group) and a group that undertook conventional ESD (C-ESD group) to compare the speed of submucosal dissection. In addition, the data of consecutive 10 patients with eleven gastric lesions was collected using electronic medical records to clarify the inaugural clinical outcomes of gastric ESD using MLTD. RESULTS: The median (interquartile range) speed of submucosal dissection in the M-ESD and C-ESD groups were 141.5 (60.9-177.6) mm2/min and 35.5 (20.8-52.3) mm2/min, respectively; submucosal dissection was significantly faster in the M-ESD group (p < 0.05). The rate of en bloc resection and R0 resection was 100% in both groups, and there were no perforation in either group. The MLTD attachment time was 2.5 ± 0.9 min and the MLTD extraction time was 1.0 ± 1.1 min. Clinical outcomes of MLTD in gastric ESD were almost the same as those of ex vivo pilot study. CONCLUSIONS: MLTD increased the speed of submucosal dissection in ESD and was similarly effective when used by expert and trainee endoscopists without perforation. MLTD can potentially ensure a safer and faster ESD.

Evaluation of the risk of metachronous multiple squamous cell carcinoma of the head and neck after transoral surgery based on the genetic polymorphisms of alcohol dehydrogenase 1B and aldehyde dehydrogenase 2.

Patients with superficial head and neck squamous cell carcinoma (HNSCC) can be completely treated by techniques of transoral surgery (TOS). The aim of this study was to evaluate the risk of metachronous multiple HNSCC arising after TOS based on alcohol dehydrogenase 1B (ADH1B) and aldehyde dehydrogenase 2 (ALDH2). We registered patients who underwent TOS for superficial HNSCC. Buccal cell samples were obtained by using a cotton swab to examine two single nucleotide polymorphisms in ADH1B and ALDH2 genotyping. We used Cox proportional hazards models to examine the risk of metachronous HNSCC. A total of 198 patients who underwent TOS for HNSCC were evaluated. In multivariate analysis, risks for second HNSCC were ADH1B*1/*1 [hazard ratio (HR), 1.88; 95% confidence interval (CI), 1.11-3.19; P = 0.02], ALDH2*1/*2 (HR, 2.11; 95% CI, 1.00-5.16; P = 0.048) and alcohol consumption before TOS (HR, 1.17; 95% CI, 1.06-1.27; P = 0.01). The 5-year incidence rates of second primary HNSCC in the temperance group and the non-temperance group were 20.8 and 46.5%, respectively (HR, 0.54; 95% CI, 0.31-0.92; P = 0.02). Cumulative development rates of third HNSCC in the temperance group and non-temperance group at 10 years were 11.3 and 36.1%, respectively (HR, 0.19; 95% CI, 0.03-0.65; P = 0.006). ADH1B*1/*1, ALDH2*1/*2 and moderate or heavy alcohol consumption before treatment are independent risk factors of metachronous HNSCC. Since it was shown that temperance decreased the incidences of second and third metachronous HNSCC, advice to discontinue alcohol drinking is necessary.

Magnet-assist endoscopic augmentation of the lower esophageal sphincter for treatment of gastroesophageal reflux disease: cadaveric and survival studies in a porcine model (with video).

BACKGROUND: Augmentation of the lower esophageal sphincter (LES) is the primary goal of both surgical and endoscopic therapies for gastroesophageal reflux disease (GERD). The feasibility, efficacy, safety, and reversibility of a newly developed endotherapy for GERD using intraluminal magnets referred to as a magnet closure device (MCD) were evaluated. METHODS: This study involved nine cadaveric and six survival pigs. The MCD consisted of a ring neodymium magnet attached to a 2-0 polypropylene suture and suture anchor. The MCD was deployed onto the esophageal wall at the region of the LES using an endoscopic suturing device. Two to three MCDs were placed on opposing walls to induce closure of the esophageal lumen. LES pressures were measured using high-resolution manometry at the index procedure (baseline and immediately post-MCD placement) and at survival endoscopy. Endoscopic removal of the devices was performed followed by necropsy at week 2. RESULTS: MCDs were successfully deployed in all cadaveric (n = 22) and survival animals (n = 12). In cadavers, 20/22 (91%) sutures were full-thickness with no adjacent organ injury. In survival animals, mean LES pressure increased from 8.4 mmHg (baseline) to 32.4 mmHg immediately post-procedure (p < 0.01). No clinically significant adverse events occurred. Repeat endoscopy at two weeks showed intact MCDs in 4/6 (67%) animals with significant increase in median LES pressure (n = 4, 24.0 mmHg versus 7.4 mmHg [baseline], p < 0.05). Endoscopic removal of MCDs was successfully achieved. CONCLUSIONS: Endoscopic augmentation of the LES using a new MCD was feasible, safe and reversible with significantly increased LES pressures recorded. Future studies are needed to enhance durability. These preliminary results on a reversible technique are promising and may represent an attractive alternative to endoluminal GERD therapy.

Blood group O is a risk factor for delayed post-polypectomy bleeding.

BACKGROUND: Blood group O of ABO blood group system is considered as a risk factor for various bleeding events, but the relationship with endoscopic treatment-associated bleeding has yet to be investigated. This study aimed to evaluate whether blood group O is associated with delayed bleeding after colorectal endoscopic resection. METHODS: This was a retrospective observational study based on medical records at four university hospitals in Japan. We reviewed the records for consecutive patients who underwent colorectal endoscopic resection from January 2014 through December 2017. The primary outcome was the incidence of delayed bleeding, defined as hematochezia or melena, requiring endoscopy, transfusion, or any hemostatic intervention up to 28 days after endoscopic resection. Multivariate logistic regression analysis was performed to adjust the impact of blood group O on the delayed bleeding. RESULTS: Among 10,253 consecutive patients who underwent colorectal endoscopic resection during the study period, 8625 patients met the criteria. In total, delayed bleeding occurred in 255 patients (2.96%). The O group had significantly more bleeding events compared with the non-O group (A, B, and AB) (relative risk, 1.62 [95% confidence interval, 1.24-2.10]; P < 0.001). In multivariate logistic regression analysis, blood group O remained an independent risk factor for the bleeding (adjusted odds ratio, 1.60 [95% confidence interval, 1.18-2.17]; P = 0.002). CONCLUSIONS: Blood group O was associated with an increased risk of delayed bleeding in patients undergoing colorectal endoscopic resection. Preoperative screening for ABO blood group could improve risk assessments.

Prospective multicenter study to evaluate capsule endoscopy competency using a validated assessment tool.

BACKGROUND AND AIMS: Capsule endoscopy (CE) is an established, noninvasive modality for examining the small bowel. Minimum training requirements are based primarily on guidelines and expert opinion. A validated tool to assess the competence of CE is lacking. In this prospective, multicenter study, we determined the minimum number of CE procedures required to achieve competence during gastroenterology fellowship; validated a capsule competency test (CapCT); and evaluated any correlation between CE competence and endoscopy experience. METHODS: We included second- and third-year gastroenterology fellows from 3 institutions between 2013 and 2018 in a structured CE training program with supervised CE interpretation. Fellows completed the CapCT with a maximal score of 100. For comparison, expert faculty completed the same CapCT. Trainee competence was defined as a score ≥90% compared with the mean expert score. Fellows were tested after 15, 25, and 35 supervised CE interpretations. CapCT was validated using expert consensus and item analysis. Data were collected on the number of previous endoscopies. RESULTS: A total of 68 trainees completed 102 CapCTs. Fourteen CE experts completed the CapCT with a mean score of 94. Mean scores for fellows after 15, 25, and 35 cases were 83, 86, and 87, respectively. Fellows with at least 25 interpretations achieved a mean score ≥84 in all 3 institutions. CapCT item analysis showed high interobserver agreement among expert faculty (k = 0.85). There was no correlation between the scores and the number of endoscopies performed. CONCLUSION: After a structured CE training program, gastroenterology fellows should complete a minimum of 25 supervised CE interpretations before assessing competence using the validated CapCT, regardless of endoscopy experience.

Endoscopic magnet placement into subadventitial tunnels for augmenting the lower esophageal sphincter using submucosal endoscopy: ex vivo and in vivo study in a porcine model (with video).

BACKGROUND AND AIMS: Endolumenal therapies serve as a treatment option for GERD. This study aimed to determine if magnets could be placed endoscopically using the adventitial layer to create a subadventitial space near the esophagogastric junction to augment the lower esophageal sphincter using submucosal endoscopy. METHODS: This study consisted of 2 phases, ex vivo and in vivo, with domestic pig esophagus. A long submucosal tunnel was made at the mid to lower esophagus. The muscularis propria was incised by a needle-knife within the submucosal tunnel. A subadventitial tunnel was made by biliary balloon catheter blunt dissection, and a magnet was deployed in the subadventitial space. The same maneuver was done within the opposing esophageal wall, with magnet placement in the opposing subadventitial space. RESULTS: Submucosal tunnels and subadventitial tunnels were successful without perforation ex vivo in all attempts and in 9 of 10 cases, respectively. Magnets were deployed in the subadventitial space in 7 cases. Magnets connected and separated with atraumatic endoscope passage into the stomach and reconnected when the endoscope was withdrawn under fluoroscopy in 5 of 7 cases (71.4%). In vivo submucosal tunnels and subadventitial tunnels were successful in all 5 cases, and magnet augmentation was functionally active in 4 cases (80%). CONCLUSION: Subadventitial tunnels were feasible and could represent a new working space for endoscopic treatment. Endoscopic placement of magnets within the subadventitial space may be an attractive alternative endolumenal therapy for GERD.

Efficacy and safety of an internal magnet traction device for endoscopic submucosal dissection: ex vivo study in a porcine model (with video).

BACKGROUND: Appropriate traction allows for safer and easier endoscopic submucosal dissection (ESD). The aim of this study was to evaluate the efficacy and safety of an internal magnet traction device (MTD) for ESD in an ex vivo porcine model. METHODS: The MTD consisted of a small neodymium magnet and a suture attached to a through-the-scope clip. A circumferential mucosal incision was completed around a 30-mm diameter template that served as the target lesion. The first MTD was deployed at the proximal edge of the lesion. A second MTD was deployed on the wall opposite the lesion. With both magnets connected, this created traction or lifting of the target lesion towards the opposing wall during submucosal dissection. Primary endpoint was comparison of submucosal dissection times between conventional ESD (C-ESD) and MTD-assisted ESD (MTD-ESD). RESULTS: Twenty lesions along the anterior wall, posterior wall and greater curvature were resected using either C-ESD or MTD-ESD. The submucosal dissection time in MTD-ESD was significantly shorter than C-ESD (median: 6.4 [interquartile range {IQR} 4.6-8.7] min vs. 14.4 min [IQR 11.8-18.0], p < 0.05). There was a significant difference between MTD-ESD and C-ESD in total procedure times for lesions on the posterior gastric wall and greater curvature (median: 23.0 min [IQR 21.1-24.5] vs. 29.2 min [IQR 24.8-33.2], p < 0.05) with no difference for lesions on the anterior gastric wall (median: 18.8 min [IQR 15.5-20.5] vs. 17.1 min [IQR 13.1-20.0], p = 0.5). The number of muscularis propria injuries per lesion was significantly lower in MTD-ESD than C-ESD (median: 0 [IQR 0-0] vs. 1 [IQR 0-2], p < 0.05). CONCLUSIONS: MTD for ESD is effective and safe when compared to C-ESD. This approach significantly reduced submucosal dissection times with less injury to the muscularis propria. Furthermore, MTD-ESD was particularly beneficial for more challenging gastric lesions located on the posterior wall and greater curvature.

An internal magnet traction device reduces procedure time for endoscopic submucosal dissection by expert and non-expert endoscopists: ex vivo study in a porcine colorectal model (with video).

BACKGROUND: Efficacy of an internal magnet traction device (MTD) for gastric endoscopic submucosal dissection (ESD) by an expert endoscopist has been reported. We hypothesized that use of the MTD would enhance the performance of colorectal ESD in a non-expert endoscopist in ESD compared to the conventional technique. Primary aim of this study was to compare procedure times between conventional ESD (C-ESD) and MTD-assisted ESD (MTD-ESD) by expert and non-expert endoscopists in ESD. Secondary aims included rate of en bloc resection, iatrogenic injury, visualization score of the submucosal layer, and endoscopist satisfaction score. METHODS: A total of 56 lesions were created in an ex vivo porcine colorectum. Two endoscopists completed C-ESD (n = 28) and MTD-ESD (n = 28). Lesions measured 3 cm in diameter and were located on either the anterior or posterior colorectal wall. The MTD consisted of a small neodymium magnet and nylon monofilament attached to a through-the-scope clip. The first MTD was deployed on the opposing colorectal wall of the target lesion and a second MTD was then deployed directly onto the distal margin of the lesion. RESULTS: Total procedure time for MTD-ESD was significantly shorter than C-ESD for both expert (median: 15.8 vs. 19.3 min, p < 0.05) and non-expert (median: 21.3 vs. 33.9 min, p < 0.001) endoscopists. All lesions were resected en bloc. There was no iatrogenic muscularis propria injury in the MTD-ESD group. For both the expert and non-expert, scores for MTD-ESD were significantly higher for submucosal layer visualization (p < 0.05) and endoscopist satisfaction (p < 0.001) compared to C-ESD. CONCLUSIONS: Use of the MTD significantly reduced procedure time for both expert and non-expert endoscopists performing ESD. Improving the efficiency, safety, and satisfaction of ESD with such a device particularly for non-expert endoscopists is appealing and could potentially minimize the complexity and duration of the procedure allowing for more widespread use of the technique.

Endoscopic full-thickness resection using suture loop needle T-tag tissue anchors in the porcine stomach (with video).

BACKGROUND AND AIMS: Endoscopic full-thickness resection (EFTR) is still challenging, and a reliable technique is desirable. The aim of this study was to evaluate the feasibility of controlled EFTR using a pseudopolyp made from suture loop needle T-tag (SLNT) tissue anchors in ex vivo porcine stomachs. METHODS: Five pig stomachs were used. Two concentric circumferential border mucosal incisions were made to facilitate isolating a target lesion for full-thickness excision and pseudopolyp formation. SLNT tissue anchors were placed with a fishing line around the edges of the larger outer incision by endoscopic suturing. A suture pulley was created in the center of the targeted area and brought outside for traction. A large inverted pseudopolyp of the targeted lesion was made, visualizing apposing serosa with traction on the suture pulley while simultaneously cinching the encircling fishing line. EFTR was then performed on the isolated targeted tissue with the use of a needle-knife. RESULTS: Pseudopolyps were successful in all attempts. In the first attempt the encircling fishing line was cut, releasing the pseudopolyp during EFTR, with obvious leak. The remaining 4 EFTRs were performed with intact serosal apposing pseudopolyps and no air leaks. The median number of SLNT tissue anchors placed for a pseudopolyp was 5 (interquartile range, 4-5). The median size of full-thickness lesions was 37 mm (interquartile range, 29-49) and the median maximum pressure for the leak testing 9 mm Hg (interquartile range, 4-14) in the successful 4 attempts. CONCLUSION: This proof of principle study suggests that EFTR with SLNT-fashioned pseudopolyps is feasible.

Dual-focus versus conventional magnification endoscopy for the diagnosis of superficial squamous neoplasms in the pharynx and esophagus: a randomized trial.

BACKGROUND AND STUDY AIMS: Conventional magnification narrow-band imaging (CM-NBI) endoscopy has demonstrated high diagnostic accuracy for superficial squamous neoplasms in the pharynx and esophagus. This study aimed to evaluate the diagnostic utility of the newly developed dual-focus NBI (DF-NBI) compared with that of CM-NBI. PATIENTS AND METHODS: We recruited patients with squamous cell carcinoma (SCC) in the head and neck, or esophagus, or with a history of SCC. The primary endpoint of this prospective controlled non-inferiority trial was the sensitivity of DF-NBI and CM-NBI for detecting superficial carcinoma in the pharynx and esophagus. Secondary endpoints included other diagnostic values and the resolving power of each endoscope. Superficial carcinoma was defined as high grade dysplasia and SCC invading up to the submucosal layer. RESULTS: The study included 93 patients. A total of 28 superficial carcinomas were detected in the pharynx and esophagus. The sensitivities of DF-NBI and CM-NBI for superficial carcinoma were 82 % and 71 %, respectively. The lower limit of the 90 % confidence interval for the difference between the sensitivities exceeded the non-inferiority threshold. The specificity and overall accuracy of DF-NBI vs. CM-NBI were 93 % vs. 90 % and 91 % vs. 86 %, respectively (both non-significant differences). The maximum resolving power of a conventional magnification endoscope was significantly higher than a dual-focus endoscope (7.2 µm vs. 11.6 µm: P < 0.001). CONCLUSIONS: The findings indicate the non-inferiority of DF-NBI versus CM-NBI in detecting superficial carcinoma in the pharynx and esophagus. DF-NBI appears to have a resolving power that, although significantly lower, is sufficient to achieve high diagnostic accuracy, comparable to that of CM-NBI.University Hospital Medical Information Network (UMIN, No. 000007585).

Effectiveness of color intensity analysis using updated autofluorescence imaging systems for serrated lesions.

BACKGROUND AND AIM: We previously reported the effectiveness of color intensity analysis using autofluorescence imaging (AFI) for differentiating colorectal neoplastic lesions from non-neoplastic lesions. However, the ability of AFI systems for differentiating serrated lesions has not been evaluated. In the present study, we assessed the effectiveness of color intensity analysis using updated AFI systems for evaluating serrated lesions. METHODS: We retrospectively reviewed the data for 48 consecutive patients with 87 serrated lesions that were examined using updated AFI systems and resected at Jikei University Hospital. The mean green/red (G/R) ratio, which is obtained by dividing the mean green color intensities by the mean red color intensities, was calculated for each serrated lesion and compared between hyperplastic polyps, sessile serrated adenomas/polyps (SSA/P) with cytological dysplasia, and SSA/P without cytological dysplasia. We also assessed the area under the receiver operating characteristic curve (AUC) for determining SSA/P (both with and without cytological dysplasia) and SSA/P with cytological dysplasia. RESULTS: The AUC for determining SSA/P was 0.68; however, the AUC for determining SSA/P with cytological dysplasia was 0.97. With a cut-off for the G/R ratio of <0.93, the sensitivity, specificity, positive predictive value, and negative predictive value for SSA/P with cytological dysplasia were 95.5%, 91.0%, 77.8%, and 98.3%, respectively. CONCLUSION: Color intensity analysis of serrated lesions using updated AFI systems could effectively distinguish SSA/P with cytological dysplasia from hyperplastic polyps and SSA/P without cytological dysplasia.

Closure of iatrogenic large mucosal and full-thickness defects of the stomach with endoscopic interrupted sutures in in vivo porcine models: are they durable enough?

BACKGROUND: In this study, we evaluated the technical feasibility of mucosal approximation of large ulcers via an endoscopic suturing system after endoscopic submucosal dissection (ESD), assessed the durability of these sutures, and compared this technique with serosal apposition of full-thickness gastric wall defects using the same device. METHODS: Post-ESD ulcers were closed with mucosal apposition in 7 pigs, and endoscopic full-thickness resection (EFTR) defects were closed with serosal apposition in 3 pigs. Pigs recovered for 1 week; they were then euthanized and necropsies were performed. RESULTS: Primary defect closure was achieved in 85.7% of the post-ESD closures and in 100% of the post-EFTR closures (p = 0.67). All pigs survived for 1 week. At necropsy, sutures had loosened in the post-ESD animals, although only minor deformity of the ulcer edges was observed in all repaired post-ESD ulcers. Meanwhile, all of the post-EFTR defect closures were sustained for 1 week. CONCLUSIONS: Primary closure of post-therapeutic defects can be accomplished using the device. Inverted serosal apposition provides a more durable and reliable repair than everted mucosal apposition.

A feasibility study of chemically assisted endoscopic submucosal mechanical dissection using mesna for superficial esophageal squamous cell carcinomas.

BACKGROUND: Injection of mesna into submucosal layers was recently reported to chemically soften connective tissue and facilitate the gastric endoscopic submucosal dissection (ESD) procedure. This study aimed to evaluate the safety and feasibility of similarly using mesna for esophageal ESD (mesna ESD). METHODS: We performed mesna ESD in 20 consecutive patients with superficial esophageal squamous cell carcinomas (SESCCs). To do this, a submucosal fluid cushion was initially formed using sodium hyaluronate, and the esophageal lesion was circumferentially isolated with a short blade needle-knife. Mesna solution was then injected into the submucosal layer, which was dissected mechanically by cleavage using the tip of a cap-fitted endoscope. The number of electrosurgical incisions was recorded by computer software in real time. The data from 20 conventional ESD procedures without mesna (consecutive 10 SESCCs pre and post the 20 consecutive mesna ESD) were used for comparison to evaluate the mesna ESD. RESULTS: The mesna ESDs achieved en bloc and R0 resection success rates of 100 and 95 %, respectively. There was no perforation or uncontrollable hemorrhage during and after mesna ESD, and the median procedural time of submucosal dissection was significantly less with mesna ESD than with conventional ESD (median; 8 vs. 15 min, P < 0.05). There were also significantly fewer electrosurgical incisions made during the mesna ESD than with conventional ESDs (median; 65 vs. 183 times, P < 0.01). CONCLUSIONS: Mesna ESD for SESCCs is a safe procedure with the potential to facilitate esophageal ESD.

A double-blind, block-randomized, placebo-controlled trial to identify the chemical assistance effect of mesna submucosal injection for gastric endoscopic submucosal dissection.

BACKGROUND: Previous animal studies and a pilot clinical trial demonstrated that submucosal injection of a thiol compound called mesna could chemically soften connective tissues and thus facilitate endoscopic submucosal dissection (ESD). OBJECTIVE: To evaluate whether mesna injection could reduce procedural times for gastric ESD. DESIGN: Double-blind, block-randomized, controlled trial. SETTING: University hospital. PATIENTS: A total of 101 patients with superficial gastric cancer indicated for ESD were enrolled and randomly assigned to either the mesna or control (saline solution) group. INTERVENTION: Traditional ESD was performed with a single bolus injection of mesna or saline solution. MAIN OUTCOME MEASUREMENTS: Time for submucosal dissection (TSD). RESULTS: En bloc resection was achieved for all lesions in the mesna group (53/53) and 51 of 52 lesions (98.08%) in the control group. TSD was not statistically different between the groups (18.62 ± 13.9 [mean ± SD] minutes for the mesna group and 24.58 ± 24.55 [mean ± SD] minutes for the control group; P = .128), and there were fewer time-consuming cases (times over 30 minutes) in the mesna group compared with controls (7/53 vs 15/52; P = .049). Multivariate regression analysis demonstrated that use of mesna, specimen size, and the presence of fibrous scars were significantly correlated with TSD (P < .05). LIMITATIONS: Single-center study. CONCLUSION: TSD was not significantly different between the mesna and control injection groups, but multivariate analysis indicated that mesna injection reduced procedural challenges associated with the submucosal dissection. ( CLINICAL TRIAL REGISTRATION NUMBER: UMIN000003786.).