Predictors of technical difficulty for trainees in esophageal endoscopic submucosal dissection.

BACKGROUND: Esophageal endoscopic submucosal dissection (ESD) is technically challenging, especially for trainees, and requires a safe training system. This study aimed to identify predictors of technical difficulty facing trainees performing esophageal ESD to establish such system. METHODS: This was a single-center retrospective study of patients with esophageal cancer who underwent ESD performed by trainees between January 2010 and August 2022. Technical difficulties were defined as muscularis propria exposure and long procedure time (≥ 90 min). Factors associated with these technical difficulties were investigated. RESULTS: A total of 798 lesions in 721 patients were evaluated. Muscularis propria exposure occurred in 298 lesions (37.3%), including 10 perforations (1.3%). The procedure time was ≥ 90 min in 134 lesions (16.8%). In the multivariate analysis, tumor size ≥ 20 mm, tumors ≥ 1/2 of the circumference, and those close to previous treatment scars significantly increased the incidence of both difficulties, whereas tumors in the upper esophagus significantly decreased this incidence. Furthermore, female sex and tumors in the left wall were independent predictors of muscularis propria exposure, and elevated morphology was an independent predictor of long procedure time. Muscularis propria exposure and long procedure time occurred in more than half of the cases with three or more predictors of each difficulty. CONCLUSIONS: Large tumors and tumors close to previous treatment scars increase technical difficulties for trainees in esophageal ESD. Conversely, tumors in the upper esophagus reduce these difficulties. These results enable us to predict the difficulty level preoperatively and select appropriate cases in stepwise training.

Potential role of a novel endoscopic retrieval bag for large colorectal resected specimen: a proof-of-concept study.

Endoscopic submucosal dissection enables en bloc resection of large superficial colorectal neoplasms. However, it is sometimes challenging to retrieve a large resected specimen via the anus without sample fragmentation. A novel "bag-type" retrieval device has been developed to accomplish complete isolation and non-destructive delivery of oversized specimens. This single-center retrospective study was performed to demonstrate the efficacy of this device for large colorectal resected specimens. Among 17 patients, we identified 18 superficial colorectal lesions for which the use of a novel retrieval device (Endo Carry Large Type) was indicated at specimen delivery at a referral cancer institute from March 2021 to July 2022. The median (interquartile range) tumor size was 62.5 (52.0-79.5) mm. Retrieval of 17 (94%) of 18 resected specimens was performed using the Endo Carry Large Type, and 16 (89%) were successfully retrieved without sample fragmentation. The median (interquartile range) retrieval time was 4 (4-8) minutes, and no apparent adverse events were observed. The novel Endo Carry Large Type device can accomplish colorectal specimen retrieval safely and quickly without specimen damage and therefore may contribute to accurate pathological diagnosis.

Endoscopic resection for local residual or recurrent cancer after definitive chemoradiotherapy or radiotherapy for esophageal squamous cell carcinoma.

Chemoradiotherapy (CRT) and radiotherapy (RT) are treatment options for esophageal squamous cell carcinoma (ESCC), but local residual/recurrent cancer after CRT/RT is a major problem. Endoscopic resection (ER) is an effective treatment option for local residual/recurrent cancer. To ensure the efficacy of ER, complete removal of endoscopically visible lesions with cancer-free vertical margins is desired. This study aimed to identify the endoscopic parameters associated with the complete endoscopic removal of local residual/recurrent cancer. In this single-center, retrospective study, we used a prospectively maintained database to identify esophageal lesions that were diagnosed as local residual/recurrent cancer after CRT/RT and treated by ER between January 2012 and December 2019. We evaluated the associations of endoscopic R0 resection with findings on conventional endoscopy and endoscopic ultrasonography (EUS). In total, 98 lesions (83 cases) were identified from our database. The rate of endoscopic R0 resection was higher for flat lesions (100% versus 77%, P = 0.00014). EUS was performed for 24 non-flat lesions, and endoscopic R0 resection was achieved for 94% of lesions with an uninterrupted fifth layer. Flat lesions on conventional endoscopy and lesions with an uninterrupted fifth layer on EUS are good candidates for ER.

A single-center prospective study evaluating the usefulness of artificial intelligence for the diagnosis of esophageal squamous cell carcinoma in a real-time setting.

BACKGROUND: Several pre-clinical studies have reported the usefulness of artificial intelligence (AI) systems in the diagnosis of esophageal squamous cell carcinoma (ESCC). We conducted this study to evaluate the usefulness of an AI system for real-time diagnosis of ESCC in a clinical setting. METHODS: This study followed a single-center prospective single-arm non-inferiority design. Patients at high risk for ESCC were recruited and real-time diagnosis by the AI system was compared with that of endoscopists for lesions suspected to be ESCC. The primary outcomes were the diagnostic accuracy of the AI system and endoscopists. The secondary outcomes were sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and adverse events. RESULTS: A total of 237 lesions were evaluated. The accuracy, sensitivity, and specificity of the AI system were 80.6%, 68.2%, and 83.4%, respectively. The accuracy, sensitivity, and specificity of endoscopists were 85.7%, 61.4%, and 91.2%, respectively. The difference between the accuracy of the AI system and that of the endoscopists was - 5.1%, and the lower limit of the 90% confidence interval was less than the non-inferiority margin. CONCLUSIONS: The non-inferiority of the AI system in comparison with endoscopists in the real-time diagnosis of ESCC in a clinical setting was not proven. TRIAL REGISTRATION: Japan Registry of Clinical Trials (jRCTs052200015, 18/05/2020).

Endoscopic Submucosal Dissection for Esophageal Cancer: Current and Future.

Endoscopic submucosal dissection (ESD) has been widely used to treat superficial esophageal cancer. The advantages of esophageal ESD include a high en bloc resection rate and accurate pathological diagnosis. It enables local resection of the primary tumor and accurate identification of the risk factors for lymph node metastasis, including depth, vascular invasion, and types of invasion. Even in cases with clinical T1b-SM cancer, ESD and additional treatment can achieve radical cure, depending on the risk of lymph node metastasis. Esophageal ESD will be increasingly vital in minimally invasive and effective esophageal cancer treatment. This article describes the current status and prospects of esophageal ESD.

Predictors of stricture after non-circumferential endoscopic submucosal dissection of the esophagus and single-dose triamcinolone injection immediately after the procedure.

BACKGROUND AND AIMS: Local triamcinolone (TA) injection is widely used to prevent stricture formation after endoscopic submucosal dissection (ESD). However, stricture develops in up to 45% of patients despite this prophylactic measure. We therefore conducted a single-center prospective study to identify predictors of stricture after esophageal ESD and local TA injection. METHODS: Patients who underwent esophageal ESD and local TA injection and who were comprehensively assessed for lesion- and ESD-related factors were included in the study. Multivariate analyses were conducted to identify the predictors of stricture. RESULTS: A total of 203 patients were included in the analysis. Multivariate analysis identified residual mucosal width ≤5 mm (odds ratio [OR], 29.0; P < .0001) or 6 to 10 mm (OR, 3.7; P = .04), history of chemoradiotherapy (OR, 5.1; P = .045), and tumor in the cervical or upper thoracic esophagus (OR, 3.8; P = .018) as independent predictors of stricture. Based on the ORs of the predictors, patients were stratified into 2 groups according to stricture risk: patients in the high-risk group (residual mucosal width ≤5 mm or 6-10 mm with another predictor) had a stricture rate of 52.5% (31 of 59 cases), and patients in the low-risk group (residual mucosal width ≥11 mm or 6-10 mm without other predictors) had a stricture rate of 6.3% (9 of 144 cases). CONCLUSIONS: We identified predictors of stricture after ESD and local TA injection. Local TA injection prevented stricture formation after ESD in low-risk patients but was not sufficient to prevent stricture in high-risk patients. Additional interventions should thus be considered in high-risk patients. (University Hospital Medical Network Clinical Trials Registry number: UMIN 000028894.).

Impact of endoscopic surveillance on mortality of metachronous esophageal and head and neck cancer after esophageal endoscopic resection.

BACKGROUND AND AIM: As more superficial esophageal cancer (EC) patients are being treated with endoscopic resection (ER), it is important to understand the outcomes, including survival data, of patients who develop metachronous EC and head and neck cancer (HNC). We aimed to evaluate the long-term surveillance and survival outcomes of metachronous EC and HNC after esophageal ER. METHODS: This study included 627 patients who underwent ER of superficial esophageal squamous cell carcinoma from 2008 to 2016 and were generally followed by annual or biannual esophagogastroduodenoscopy up to 2019 at Osaka International Cancer Institute. Data on metachronous cancer development and causes of death were collected from an integrated database of hospital-based cancer registry and Vital Statistics of Japan. RESULTS: During a median (range) follow-up period of 67.4 (3.8-142.7) months, 230 patients (36.7%) developed 500 metachronous ECs and 126 patients (20.1%) developed 239 metachronous HNCs, post-ER of index EC. The 3-year, 5-year, and 7-year cumulative incidences were 25.8%, 36.0%, and 43.6% for metachronous EC and 10.9%, 16.0%, and 26.9% for metachronous HNC, respectively. No patients died of metachronous EC, and only seven patients (1.1%) died of metachronous HNC. The 3-year, 5-year, and 7-year disease-specific survival rates were 99.8%, 99.6%, and 98.6%, respectively. CONCLUSIONS: The incidences of metachronous EC and HNC increase with time over 5 years after esophageal ER; therefore, surveillance endoscopy should be continued over 5 years. Endoscopic surveillance is useful for survivors after esophageal ER given the high incidence and extremely low mortality of metachronous EC and HNC.

Indication of emergency colonoscopy after colorectal endoscopic submucosal dissection: A proposal of hematochezia scale.

BACKGROUND AND AIM: Hematochezia is a major adverse event associated with colorectal endoscopic submucosal dissection (ESD). This study aimed to distinguish between hematochezia that required endoscopic hemostasis and hematochezia that required no hemostasis. METHODS: This retrospective study included consecutive patients who underwent ESD for colorectal tumors at the Osaka International Cancer Institute between September 2017 and August 2020. The exclusion criteria were as follows: patients with coexisting advanced colorectal cancers or inflammatory bowel diseases, patients who received incomplete ESD or emergency surgery, or patients who underwent ESD for multiple lesions. We evaluated whether the patients had hematochezia and underwent emergency colonoscopy and hemostasis during hospitalization. The degree of hematochezia in the saved photographs was assessed using the hematochezia scale and classified as mild, moderate, or severe. Blood pressure, heart rate, time from ESD to first hematochezia, and total number of hematochezia episodes were also evaluated. RESULTS: Among the 437 patients who underwent ESD, 44 were excluded, and 393 patients were evaluated. Hematochezia was observed in 100 patients (25%). Emergency colonoscopy was performed in 12 patients (3%), and hemostasis was required in six patients (2%). For patients with hematochezia, only mild hematochezia and hematochezia that developed ≤ 48 h after ESD were significantly associated with no intervention for hemostasis. The positive predictive value for no intervention for hemostasis was 100% (93-100%) for mild hematochezia and 98% (93-100%) for hematochezia ≤ 48 h. CONCLUSIONS: Mild hematochezia and hematochezia ≤ 48 h were negative predictors of hemostasis, in which emergency colonoscopy may be avoided.

Safety and efficacy of cold versus hot snare polypectomy including colorectal polyps ≥1 cm in size.

Cold snare polypectomy (CSP; polypectomy without electrocautery) has spread rapidly worldwide during the past decade in what has been called "Cold Revolution". We performed a PubMed literature search for studies investigating CSP outcomes for colorectal polyps. Five randomized controlled trials (RCTs) assessed the complete resection rates (CRRs). The CRRs were similar regardless of the presence or absence of electrocautery, and the efficacy of submucosal injection for better CRRs is still controversial. Eight RCTs assessed the adverse events. The incidence of intraprocedural bleeding with cold procedures was comparable to or higher than that of hot procedures. The incidences of delayed bleeding were comparable to or lower with cold procedures, especially in patients taking anticoagulants. Fifteen studies have been reported on CSP for large (≥1 cm) colorectal polyps (10 retrospective studies, four prospective single-arm studies, and one prospective RCT). These studies reported that the safe cold procedures (a low intra- and post-procedural bleeding rate without perforation) could be implemented for lesions ≥1 cm. However, considering the incision depth of CSP and the local recurrence rate based on the current evidence, only large sessile serrated lesions (SSLs) can be candidates for cold procedures, and large adenomas should not be candidates for this procedure. Based on the current evidence, CSP seems to be the appropriate standard procedure for sub-centimeter colorectal low-grade adenomas due to its safety and simplicity. Thus, large SSLs can be candidates for cold procedures; however, careful inspection and further prospective studies are warranted to confirm the procedure's clinical relevance.

Phase Transition from the Interdigitated to Bilayer Membrane of a Cationic Surfactant Induced by Addition of Hydrophobic Molecules.

Although the transition between a bilayer and an interdigitated membrane of a surfactant and lipid has been widely known for long, its mechanism remains unclear. This study reveals the transition mechanism of a cationic surfactant, dioctadecyldimethylammonium chloride (DODAC), through experiments and theoretical calculations. Experimentally, the transition from the interdigitated to bilayer structure in the gel phase of DODAC is found to be induced by adding hydrophobic molecules such as n-alkane and its derivatives. Further addition induces a different transition to another bilayer phase. Our theory, considering the competition of the electrostatic interaction between cationic headgroups and the hydrophobic interaction emerging at the alkyl-chain ends exposed to water, reproduces these two phase transitions. In addition, changes in alkyl-chain packing in the membranes at these transitions are reproduced. The underlying mechanism is that the interdigitated membrane is formed at a small additive content due to electrostatic repulsion. As the energetic disadvantage with respect to the hydrophobic interaction becomes dominant as the content increases, the transition to the bilayer occurs at a specific content. The bilayer-bilayer transition at a higher content is induced by the change in the balance of these interactions. Based on a similar concept, we suggest the mechanism of the additive-induced bilayer-interdigitated transition of phospholipids, i.e., neutrally charged (zwitterionic) surfactants.

Dairy cattle behavior classifications based on decision tree learning using 3-axis neck-mounted accelerometers.

Demand has been increasing recently for an automated monitoring system of animal behavior as a tool for the management of livestock animals. This study investigated the association between the behavior of dairy cattle and the acceleration data collected using three-axis neck-mounted accelerometers, as well as the feasibility of improving the precision of behavior classifications through machine learning. In total 38 Holstein dairy cows were used, and kept in four different farms. A logger was mounted to each collar to obtain acceleration data for calculating the activity level and variations. At the same time the behavior of the cattle was observed visually. Characteristic acceleration waves were recorded for eating, rumination, and lying, respectively; and the activity level and variations were significantly different among these behaviors (p < 0.01). Decision tree learning was performed on the data set from Farm A and validated its precision; which proved to be 99.2% in cross-validation, and 100% in test data sets from Farms B to D. This study showed that highly precise classifications for eating, rumination, and lying is possible by using decision tree learning to calculate the activity level and variations of cattle based on the data obtained by three-axis accelerometers mounted to a collar.

Selective through-holing of anodic porous alumina membranes with large area.

Anodic porous alumina membranes with site controlled through-holes were prepared by the formation of a masking layer on the surface of anodic porous alumina and subsequent selective second anodization in concentrated sulfuric acid to form a readily soluble layer. After the anodization, the residual Al substrate was removed, and the highly soluble alumina layer formed in concentrated sulfuric acid was dissolved selectively by wet etching. An advantageous point of this process is the controllability of the pattern of through-holes, and the preparation of large samples with selective through-holes is possible. The pattern of through-holes was controlled by changing the mask pattern formed on the surface of anodic porous alumina. The alumina membranes obtained by this process are expected to be used for various applications that require porous alumina membranes with site controlled through-holes.

Angiopoietin Balance in Septic Shock Patients With Acute Kidney Injury: Effects of Direct Hemoperfusion With Polymyxin B-Immobilized Fiber.

Acute kidney injury (AKI) occurs in approximately 50% of patients in septic shock, and mortality from septic AKI is extremely high. Angiopoietin levels may play a role in the pathogenesis of vascular permeability. It was reported that direct hemoperfusion with a polymyxin B-immobilized fiber column (DHP-PMX) therapy ameliorates the angiopoietin balance in patients with sepsis. Although dysregulated angiopoietin balance in sepsis has been demonstrated, mechanisms underlying the development of AKI in sepsis have not been identified. We investigated angiopoietin levels in septic patients with/without AKI treated with DHP-PMX therapy. We used an enzyme-linked immunoassay to measure serum angiopoietin-1 and -2 levels in 38 septic shock patients treated with DHP-PMX. The renal function of all patients was normal for less than 3 months. Twenty-seven of the patients were diagnosed with AKI. The angiopoietin-1 level of the AKI group was significantly lower than that of the non-AKI group at the initiation of DHP-PMX therapy, but there was no significant difference between the two groups at the end of DHP-PMX therapy. In the AKI group with recovery, the mean angiopoietin-1 level at the end of DHP-PMX therapy was significantly elevated compared to the level before DHP-PMX therapy, and the mean angiopoietin-2 level at the end of DHP-PMX therapy was significantly decreased compared to the level before DHP-PMX therapy. These results suggest that angiopoietins may play a role in the pathogenesis of AKI and that DHP-PMX therapy may ameliorate the angiopoietin balance in AKI patients with sepsis.

Organically modified titania having a metal catalyst: a new type of liquid-phase hydrogen-transfer photocatalyst working under visible light irradiation and H2-free conditions.

Organically modified titania having a metal catalyst (OMTC), 2,3-dihydroxynaphthalene-modified titania having palladium metal, successfully worked as a hydrogen-transfer (C[double bond, length as m-dash]C hydrogenation) photocatalyst in the presence of triethanolamine as the hydrogen source under visible light irradiation and hydrogen-free conditions.