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Objectives: Although color information is important in gastrointestinal endoscopy, there are limited studies on how endoscopic images are viewed by people with color vision deficiency. We aimed to investigate the differences in the visibility of blood vessels during endoscopic submucosal dissection (ESD) among people with different color vision characteristics and to examine the effect of red dichromatic imaging (RDI) on blood vessel visibility. Methods: Seventy-seven pairs of endoscopic images of white light imaging (WLI) and RDI of the same site were obtained during colorectal ESD. The original images were set as type C (WLI-C and RDI-C), a common color vision. These images were computationally converted to simulate images perceived by people with color vision deficiency protanope (Type P) or deutanope (Type D) and denoted as WLI-P and RDI-P or WLI-D and RDI-D. Blood vessels and background submucosa that needed to be identified during ESD were selected in each image, and the color differences between these two objects were measured using the color difference (ΔE 00) to assess the visibility of blood vessels. Results: ΔE 00 between a blood vessel and the submucosa was greater under RDI (RDI-C/P/D: 24.05 ± 0.64/22.85 ± 0.66/22.61 ± 0.64) than under WLI (WLI-C/P/D: 22.26 ± 0.60/5.19 ± 0.30/8.62 ± 0.42), regardless of color vision characteristics. This improvement was more pronounced in Type P and Type D and approached Type C in RDI. Conclusions: Color vision characteristics affect the visibility of blood vessels during ESD, and RDI improves blood vessel visibility regardless of color vision characteristics.
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A 73-year-old male patient was referred to us with a long Barrett's esophagus (BE). He had a history of pulmonary embolism under anticoagulant therapy. Esophagogastroduodenoscopy showed a C8M9 BE with no macroscopic lesions. Random biopsies from the BE revealed multifocal high-grade dysplasia. The case was discussed in a multidisciplinary team conference and the decision for full resection of BE with endoscopic submucosal dissection (ESD) was made. Considering the large ESD resection and the high risk of stricture, we developed a novel preventive technique: the "steroid lifting method" for submucosal injection during ESD. Complete circumferential ESD with en bloc resection was performed using the "steroid lifting method", without adverse events. Oral liquids were initiated on day 1 and the patient was discharged on day 4. Oral prednisolone (30 mg per day) was started and tapered for a total of 6 weeks. The pathological examination confirmed multifocal high-grade dysplasia, with radical and curative resection. The patient had neither stricture, dysphagia nor recurrence of Barrett's mucosa at the 2, 6, 12, and 24-month follow-up. International guidelines recommend oral prednisolone and triamcinolone injection to prevent stricture formation in large ESD of esophageal squamous cell carcinoma. However, there is no solid data on BE ESD. The risk factors for stricture formation and the optimal preventive management after large BE ESD is not known. The "steroid lifting method" might be an option in this context. Large prospective studies addressing stricture formation and preventive measures on BE ESD are necessary.
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A 67-year-old man visited our hospital complaining of dark-colored urine and upper abdominal pain. Magnetic resonance cholangiopancreatography showed stricture of the distal bile duct, and contrast-enhanced computed tomography showed irregular thickening of the distal bile duct wall. However, no enlarged lymph nodes, pancreatic tumors, or other neoplastic lesions were apparent around the bile duct. Endoscopic ultrasonography and intraductal ultrasonography showed irregular thickening of the inner hypoechoic layer without the disappearance of the innermost thin hyperechoic layer. On the basis of these findings, we considered that the bile duct lesion was of non-epithelial origin. Thus, we repeatedly performed bile duct biopsies from the same site under fluoroscopy to obtain a sample of the submucosal tissue. The pathological diagnosis was diffuse large B-cell lymphoma, and the patient received systemic chemotherapy (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone). After six courses of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone, positron emission tomography-computed tomography showed the disappearance of 18-fluorodeoxyglucose uptake in the bile duct and endoscopic retrograde cholangiography showed improvement of the bile duct stricture. Endoscopic findings and repeated biopsies were useful in making the diagnosis of primary biliary diffuse large B-cell lymphoma.
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Objectives: We aimed to identify independent factors for intraoperative endoscopic lens cloudiness during gastric and colorectal endoscopic submucosal dissections, investigate the effectiveness of Cleastay, an endoscope anti-fog solution, and examine factors associated with severe submucosal fat deposition. Methods: A total of 220 patients who underwent gastric or colorectal endoscopic submucosal dissections in two institutions between January 2022 and October 2023 were included. Significant factors related to cloudiness were determined using univariate and multivariate analyses. Patient background and tumor characteristics related to severe submucosal fat deposition were investigated, and the degree of intraoperative endoscopic lens cloudiness and outcomes were compared between the Cleash and Cleastay groups. Results: In the multivariate analysis, factors increasing lens cloudiness included long procedure time (odds ratio [OR], 17.51; 95% confidence interval [CI], 1.52-202.08), stomach (vs. colon; OR, 5.08; 95% CI, 1.99-12.96), and severe submucosal fat deposition (OR, 12.19; 95% CI, 5.02-29.60). Conversely, the use of Cleastay (vs. Cleash; OR, 0.066; 95% CI, 0.021-0.21) was identified as a factor reducing cloudiness. Location analysis revealed that severe submucosal fat deposition was more common in the upper stomach and right colon. Conclusions: It was suggested that Cleastay is more useful for endoscopic submucosal dissection of the upper stomach and right colon, where severe submucosal fat deposition is expected.
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Papillary adenomas, known precursors to papillary adenocarcinoma, warrant close monitoring due to their malignant potential. Historically, surgical resection represented the mainstay of treatment for papillary adenomas with intraductal extension. However, recent advancements in endoscopic techniques have facilitated the adoption of endoscopic papillectomy as a minimally invasive alternative in carefully selected cases. We report a case of an 82-year-old woman with a diagnosis of papillary adenoma exhibiting intraductal extension. This was managed with a novel endoscopic technique, balloon catheter-assisted endoscopic resection. Due to the obscured intraductal component of the papillary mass, a balloon occlusion catheter was deployed within the common bile duct and used as traction to facilitate endoscopic visualization of the mass. Endoscopic resection via papillectomy was subsequently performed. Histopathological examination of the resected specimen revealed a villous adenoma with high-grade dysplasia. Serial endoscopic ultrasound examinations with targeted papillary biopsies were performed to monitor for disease recurrence.
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Objectives: A relationship between endoscopic submucosal dissection (ESD) and deep vein thrombosis has been recognized. We previously reported that a high corrected midazolam dose (total midazolam dose/initial dose of midazolam used to induce sedation) is related to elevated D-dimer levels after ESD. In this study, the effect of compression stockings (CSs) in preventing thrombosis following ESD under sedation was evaluated by measuring D-dimer levels before and after ESD. Methods: The participants were patients who underwent ESD for upper gastrointestinal tumors during the period between April 2018 and October 2022. Patients with pre-ESD D-dimer levels ≥1.6 µg/m and patients with corrected midazolam doses ≤3.0 were excluded. A retrospective investigation of the relationship between CS use and high post-ESD D-dimer levels (difference in D-dimer levels ≥1.0 µg/mL between before and after ESD) was conducted. Results: There were 27 patients in the non-CS group (NCS) and 33 patients in the CS group. The number of patients with high post-ESD D-dimer levels was 13 (48.2%) in the non-CS group and six (18.2%) in the CS group; the number in the CS group was significantly lower (p = 0.024). On logistic regression analysis, a relationship was seen between the wearing of CSs and a lower number of patients with high post-ESD D-dimer levels (odds ratio 0.24, 95% confidence interval 0.08-0.79, p = 0.019). Conclusion: Wearing CSs was related to a lower risk of high post-ESD D-dimer levels. This result suggests that thrombus formation is a cause of elevated D-dimer levels after ESD.
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Objectives: To evaluate the results of inside stent therapy for unresectable malignant hilar biliary obstruction and identify factors related to stent patency duration. Methods: Of 44 patients who underwent initial inside-stent placement above the sphincter of Oddi from April 2017 to December 2022, 42 with the resolution of jaundice (clinical success rate, 95.5%) were retrospectively analyzed. Univariate and multivariate logistic regression analysis identified factors associated with stent patency duration. Results: Univariate analysis revealed significant differences in the drainage method (406 days for unilateral drainage vs. 305 days for bilateral drainage of the right and left liver lobes, p = 0.022) with or without chemotherapy (406 days with vs. 154 days without, p = 0.038). Multivariate analysis (Cox proportional hazards analysis) revealed similar results, with unilateral drainage (p = 0.031) and chemotherapy (p = 0.048) identified as independent factors associated with prolonged stent patency. Early adverse events were observed in two patients (4.8%; one cholangitis, one pancreatitis). Conclusions: Inside-stent therapy was safely performed in patients with malignant hilar biliary obstruction. Simple unilateral drainage and chemotherapy may prolong stent patency.
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Objectives: Endoscopic resection (ER) for gastric submucosal tumors (SMTs) has gained prominence in recent years, with studies emerging from various countries. However, there is a paucity of reports from Japan. We aimed to elucidate the efficacy and safety of ER for gastric SMT in Japan. Methods: In this retrospective observational study, we investigated the outcomes of consecutive patients who underwent ER for gastric SMT from January 2017 to May 2023. The outcome variables assessed included the complete resection rate, procedure time, closure-related outcomes, and the incidence of adverse events. Results: A total of 13 patients were included in the analysis. The median procedure time was 163 (55-283) min. Complete full-thickness resection was performed in seven cases, while in four cases, the serosa remained, and in two cases, the outer layer of the muscularis propria remained. In two cases where the SMT was located on the anterior side, conversion to laparoscopic surgery became necessary, resulting in a procedural success rate of 84.6% (11/13). Excluding these two cases, endoscopic closure of the defect was successfully accomplished in the remaining 11 cases. R0 resection was achieved in 12 out of 13 cases (92.3%). Although one patient had peritonitis, which was successfully treated conservatively, no other treatment-related adverse events were encountered. Conclusions: Although ER for SMT on the anterior side may be challenging, our experience revealed that ER is a safe and efficacious approach for gastric SMT.
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Objectives: Although delayed bleeding after endoscopic procedures has become a problem, currently, there are no appropriate animal models to validate methods for preventing it. This study aimed to establish an animal model of delayed bleeding after endoscopic procedures of the gastrointestinal tract. Methods: Activated coagulation time (ACT) was measured using blood samples drawn from a catheter inserted into the external jugular vein of swine (n = 7; age, 6 months; mean weight, 13.8 kg) under general anesthesia using the cut-down method. An upper gastrointestinal endoscope was inserted orally, and 12 mucosal defects were created in the stomach by endoscopic mucosal resection using a ligating device. Hemostasis was confirmed at this time point. The heparin group (n = 4) received 50 units/kg of unfractionated heparin via a catheter; after confirming that the ACT was ≥200 s 10 min later, continuous heparin administration (50 units/kg/h) was started. After 24 h, an endoscope was inserted under general anesthesia to evaluate the blood volume in the stomach and the degree of blood adherence at the site of the mucosal defect. Results: Delayed bleeding was observed in three swine (75%) in the heparin-treated group, who had a maximum ACT of >220 s before the start of continuous heparin administration. In the non-treated group (n = 3), no prolonged ACT or delayed bleeding was observed at 24 h. Conclusion: An animal model of delayed bleeding after an endoscopic procedure in the gastrointestinal tract was established using a single dose of heparin and continuous heparin administration after confirming an ACT of 220 s.
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Gossypiboma is an extremely rare adverse event occurring post-surgery, where surgical gauze is left within the body. If aseptically retained, it can lead to the formation of granulation tissue through chronic inflammation and adhesion with surrounding tissues, potentially persisting asymptomatically for many years. While diagnosis of this condition has been reported through various imaging modalities such as abdominal ultrasound and computed tomography, cases not presenting with typical findings are difficult for preoperative diagnosis, and instances where it is discovered postoperatively exist. Particularly when in contact with the gastrointestinal tract within the abdominal cavity, differentiation from submucosal tumors of the digestive tract becomes problematic. This report describes the imaging characteristics of endoscopic ultrasound and the usefulness of endoscopic ultrasound-fine-needle-aspiration for tissue diagnosis in the preoperative diagnosis of intra-abdominal gossypiboma.
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A 68-year-old man was admitted with hematochezia. Emergency computed tomography showed multiple diverticula throughout the colon. Initial colonoscopy on day 2 showed no active bleeding, but massive hematochezia on day 3 led to the performance of an emergency endoscopy. Substantial bleeding in the ileocecal area obscured the visual field, making it challenging to view the area around the bleeding site. Two endoscopic band ligations (EBLs) were applied at the suspected bleeding sites. Hemostasis was achieved without active bleeding after EBL. However, the patient developed lower right abdominal pain and fever (39.4°C) on day 6. Urgent computed tomography revealed appendiceal inflammation, necessitating emergency open ileocecal resection for acute appendicitis. Pathological examination confirmed acute phlegmonous appendicitis, with EBLs noted at the appendiceal orifice and on the anal side. This case illustrates the efficacy of EBL in managing colonic diverticular bleeding. However, it also highlights the risk of appendicitis due to EBL in cases of ileocecal hemorrhage exacerbated by poor visibility due to substantial bleeding. Endoscopists need to consider this rare but important complication when performing EBL in similar situations.
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Pancreaticoduodenectomy (PD) with combined portal vein resection sometimes causes left-sided portal hypertension, which can be a problem. An appropriate treatment strategy for hemorrhagic ectopic varices due to left-sided portal hypertension after PD has not yet been determined. We report a case of repeated variceal rupture around the pancreatojejunostomy site. A 65-year-old woman with a history of PD for pancreatic head cancer was admitted with a chief complaint of bloody stools. She was diagnosed with pancreatojejunostomy variceal rupture, and an endoscopic cyanoacrylate injection was performed. As rebleeding occurred 2 weeks after the first treatment, endoscopic cyanoacrylate injection was repeated, and hemostasis was achieved. Additionally, she had esophageal, colonic, and gastrojejunostomy varices, and the future risk of these variceal ruptures was considered very high. Hence, a splenectomy was performed to prevent rebleeding or other variceal ruptures. Endoscopic cyanoacrylate injection is a useful treatment for hemorrhagic varices around the pancreatojejunostomy site. It is also necessary to understand portal vein hemodynamics and provide appropriate additional treatment in cases of recurrent variceal rupture due to left-sided portal hypertension after PD.
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Endoscopic submucosal dissection (ESD) is a transformative advancement in the endoscopic management of superficial gastrointestinal lesions. Initially conceived for the treatment of early gastric cancer, ESD has demonstrated proficiency in achieving en-bloc resection of superficial gastrointestinal lesions. ESD has experienced widespread acceptance in Japan and East Asia; however, its adoption in the USA remains delayed. This initial hesitancy could be attributed to procedural complexity and training demands; nonetheless, recently, ESD has been gaining popularity in the USA. This is due to the advancements in endoscopic technology, tailored training programs, and cumulative evidence regarding the efficacy and safety of ESDs. This review aimed to deliberate the historical progress, current implementation, and prospective trajectory of ESDs in the USA. With ongoing clinical research, technological integration, and educational efforts, ESD is likely to become the gold standard for managing large gastrointesitinal lesions. This progress marks an imperative step toward less invasive, more precise, and patient-centric approaches regarding advanced therapeutic endoscopy in the USA.
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Objectives: For early gastrointestinal lesions, size is an important factor in the selection of treatment. Virtual scale endoscope (VSE) is a newly developed endoscope that can measure size more accurately than visual measurement. This study aimed to investigate whether VSE measurement is accurate for early gastrointestinal lesions of various sizes and morphologies. Methods: This study prospectively enrolled patients with early gastrointestinal lesions ≤20 mm in size visually. Lesion sizes were measured in the gastrointestinal tract visually, on endoscopic resection specimens with VSE, and finally on endoscopic resection specimens using a ruler. The primary endpoint was the normalized difference (ND) of VSE measurement. The secondary endpoints were the ND of visual measurement and the variation between NDs of VSE and visual measurements. ND was calculated as (100 × [measured size - true size] / true size) (%). True size was defined as size measured using a ruler. Results: This study included 60 lesions from April 2022 to December 2022, with 20 each in the esophagus, stomach, and colon. The lesion size was 14.0 ± 6.3 mm (mean ± standard deviation). Morphologies were protruded, slightly elevated, and flat or slightly depressed type in 8, 24, and 28 lesions, respectively. The primary endpoint was 0.3 ± 8.8%. In the secondary endpoints, the ND of visual measurement was -1.7 ± 29.3%, and the variability was significantly smaller in the ND of VSE measurement than in that of visual measurement (p < 0.001, F-test). Conclusions: VSE measurement is accurate for early gastrointestinal lesions of various sizes and morphologies.
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Objectives: This study aimed to determine the impact of the coronavirus disease 2019 (COVID-19) pandemic on the treatment of acute cholangitis caused by choledocholithiasis. Methods: The Japanese government declared a state of emergency in April 2020 due to the COVID-19 pandemic. We retrospectively reviewed the medical records of 309 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) for acute cholangitis caused by choledocholithiasis between April 2017 and December 2022. Results: Patients were categorized into a pregroup (n = 134) and a postgroup (n = 175), depending on whether they were diagnosed before or after the state of emergency declaration. The total number of ERCP cases and the number of ERCP cases with endoscopic stone removals increased after the state of emergency declaration. Compared with the pregroup, the numbers of patients with performance status of 0-1 and surgically altered anatomy increased, whereas the numbers of patients taking oral antiplatelets or anticoagulants and those with cerebrovascular disease decreased in the postgroup. The number of single-stage endoscopic stone removals increased and hospital stays were significantly shorter in the postgroup. No differences in adverse event rates were detected between the two groups. Conclusions: Although our hospital provides tertiary care, the number of patients with cholangitis in good general condition and no underlying disease increased after the state of emergency declaration. The COVID-19 pandemic resulted in an increase in the number of single-stage endoscopic treatments and shortened hospital stays for patients with acute cholangitis caused by choledocholithiasis. No safety issues with ERCP were detected, even during the pandemic.
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Large ileal lipomas over 2 cm can cause symptoms, that may require a resection. Due to the narrow lumen and thin walls of the ileum, endoscopic treatments can have a high risk of adverse events and require technical expertise, thus surgical resection is currently the mainstay of treatment. To overcome the technical challenges, we developed a novel method to endoscopically resect terminal ileal lipomas. The technique involves extracting the lesion into the cecum, which creates sufficient space to maneuver, and a better field of view. The lipoma is resected with endoscopic mucosal resection or endoscopic submucosal dissection. The appearance of the lipoma protruding out of the ileocecal valve resembles that of a tongue sticking out of the mouth, thus we named this the "tongue out technique". To assess the technical feasibility of this method, we retrospectively analyzed seven cases of terminal ileal lipoma that were endoscopically resected using the "tongue out technique" at NTT Medical Center Tokyo between January 2017 and October 2023. Technical success was 100% and en bloc resection was achieved in all cases. The median size was 31 (14-55) mm. Three cases were resected with endoscopic mucosal resection while endoscopic submucosal dissection was performed on the other four cases. There was one case of delayed post-endoscopic mucosal resection bleeding, which was caused by clip dislodgement. There were no perforations. No recurrence of the lipoma or associated symptoms have been observed. This new technique can allow more ileal lipomas to be treated with minimally invasive and organ-preserving endoscopic procedures.
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Objective: This study aimed to investigate the usefulness of endoscopic ultrasound-guided tissue acquisition (EUS-TA) for diagnosing focal liver lesions in patients with a history of multiple primary malignant neoplasms. Methods: Among patients who underwent EUS-TA for focal liver lesions between 2016 and 2022, those with a history of multiple malignant neoplasms were included. A histologically confirmed malignant tumor within the past 5 years before EUS-TA was defined as a history of malignant neoplasm. The primary outcomes were diagnostic ability and adverse events of EUS-TA. Results: This study included 16 patients (median age, 73 [33-90] years), the median tumor size was 32 (6-51) mm, 14 had a history of double malignant neoplasms, whereas two had triple malignant neoplasms. Malignant neoplasms were detected histologically or cytologically in all cases. Immunohistochemistry was performed in 75% (12/16), and the final diagnosis of EUS-TA was metastatic liver tumor in 12 patients, and primary malignant liver tumor in four patients. The primary site could be identified in 11 of 12 metastatic tumor cases. The diagnostic yield of EUS-TA was 100% (16/16) for differentiating benign and malignant tumors and 94% (15/16) for confirming the histological type including the primary site of metastatic lesions. No adverse events were associated with the procedure. Conclusion: EUS-TA is a useful diagnostic modality for focal liver lesions in patients with a history of multiple malignant neoplasms, allowing for the differential diagnosis of primary and metastatic tumors and identification of the primary site of metastatic lesions.
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Objective: Iodine staining on white light imaging (WLI) is the gold standard for detecting and demarcating esophageal squamous cell carcinoma (ESCC). We examined the effects of texture and color enhancement imaging (TXI) on improving the endoscopic visibility of ESCC under iodine staining. Methods: Twenty ESCC lesions that underwent endoscopic submucosal dissection were retrospectively included. The color difference between ESCC and the surrounding mucosa (ΔEe) on WLI, TXI, and narrow-band imaging was assessed, and ΔEe under 1% iodine staining on WLI and TXI. Furthermore, the visibility grade determined by endoscopists was evaluated on each imaging. Result: The median ΔEe was greater on TXI than on WLI (14.53 vs. 10.71, respectively; p < 0.005). Moreover, the median ΔEe on TXI under iodine staining was greater than the median ΔEe on TXI and narrow-band imaging (39.20 vs. 14.53 vs. 16.42, respectively; p < 0.005 for both). A positive correlation in ΔEe under iodine staining was found between TXI and WLI (correlation coefficient = 0.61, p < 0.01). Moreover, ΔEe under iodine staining on TXI in each lesion was greater than the corresponding ΔEe on WLI. The visibility grade assessed by endoscopists on TXI was also significantly greater than that on WLI under iodine staining (p < 0.01). Conclusions: The visibility of ESCC after iodine staining was greater on TXI than on WLI.
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Objectives: To identify and classify submucosal tumors by building and validating a radiomics model with gastrointestinal endoscopic ultrasonography (EUS) images. Methods: A total of 144 patients diagnosed with submucosal tumors through gastrointestinal EUS were collected between January 2019 and October 2020. There are 1952 radiomic features extracted from each patient's EUS images. The statistical test and the customized least absolute shrinkage and selection operator regression were used for feature selection. Subsequently, an extremely randomized trees algorithm was utilized to construct a robust radiomics classification model specifically tailored for gastrointestinal EUS images. The performance of the model was measured by evaluating the area under the receiver operating characteristic curve. Results: The radiomics model comprised 30 selected features that showed good discrimination performance in the validation cohorts. During validation, the area under the receiver operating characteristic curve was calculated as 0.9203 and the mean value after 10-fold cross-validation was 0.9260, indicating excellent stability and calibration. These results confirm the clinical utility of the model. Conclusions: Utilizing the dataset provided curated from gastrointestinal EUS examinations at our collaborating hospital, we have developed a well-performing radiomics model. It can be used for personalized and non-invasive prediction of the type of submucosal tumors, providing physicians with aid for early treatment and management of tumor progression.
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Objectives: Cold snare polypectomy (CSP) is widely performed for small colorectal polyps. However, small colorectal polyps sometimes include high-grade adenomas or carcinomas that require endoscopic resection with electrocautery. This study aimed to evaluate the efficacy and safety of a novel resection technique, hot snare polypectomy with low-power pure-cut current (LPPC-HSP) for small colorectal polyps, compared with CSP and conventional endoscopic mucosal resection (EMR). Methods: Records of patients who underwent CSP, EMR, or LPPC-HSP for nonpedunculated colorectal polyps less than 10 mm between April 2021 and March 2022 were retrospectively evaluated. We analyzed and compared the treatment outcomes of CSP and EMR with those of LPPC-HSP using propensity score matching. Results: After propensity score matching of 396 pairs, an analysis of CSP and LPPC-HSP indicated that LPPC-HSP had a significantly higher R0 resection rate (84% vs. 68%; p < 0.01). Delayed bleeding was observed in only two cases treated with CSP before matching. Perforation was not observed with either treatment. After propensity score matching of 176 pairs, an analysis of EMR and LPPC-HSP indicated that their en bloc and R0 resection rates were not significantly different (99.4% vs. 100%, p = 1.00; 79% vs. 81%, p = 0.79). Delayed bleeding and perforation were not observed with either treatment. Conclusions: The safety of LPPC-HSP was comparable to that of CSP. The treatment outcomes of LPPC-HSP were comparable to those of conventional EMR for small polyps. These results suggest that this technique is a safe and effective treatment for nonpedunculated polyps less than 10 mm.