Cold Vs Hot Snare Endoscopic Resection of Large Nonpedunculated Colorectal Polyps: Randomized Controlled German CHRONICLE Trial.

BACKGROUND & AIMS: Endoscopic mucosal resection (EMR) is standard therapy for nonpedunculated colorectal polyps ≥20 mm. It has been suggested recently that polyp resection without current (cold resection) may be superior to the standard technique using cutting/coagulation current (hot resection) by reducing adverse events (AEs), but evidence from a randomized trial is missing. METHODS: In this randomized controlled multicentric trial involving 19 centers, nonpedunculated colorectal polyps ≥20 mm were randomly assigned to cold or hot EMR. The primary outcome was major AE (eg, perforation or postendoscopic bleeding). Among secondary outcomes, major AE subcategories, postpolypectomy syndrome, and residual adenoma were most relevant. RESULTS: Between 2021 and 2023, there were 396 polyps in 363 patients (48.2% were female) enrolled for the intention-to-treat analysis. Major AEs occurred in 1.0% of the cold group and in 7.9% of the hot group (P = .001; odds ratio [OR], 0.12; 95% CI, 0.03-0.54). Rates for perforation and postendoscopic bleeding were significantly lower in the cold group, with 0% vs 3.9% (P = .007) and 1.0% vs 4.4% (P = .040). Postpolypectomy syndrome occurred with similar frequency (3.1% vs 4.4%; P = .490). After cold resection, residual adenoma was found more frequently, with 23.7% vs 13.8% (P = .020; OR, 1.94; 95% CI, 1.12-3.38). In multivariable analysis, lesion diameter of ≥4 cm was an independent predictor for major AEs (OR, 3.37) and residual adenoma (OR, 2.47) and for high-grade dysplasia/cancer for residual adenoma (OR, 2.92). CONCLUSIONS: Cold resection of large, nonpedunculated colorectal polyps appears to be considerably safer than hot EMR; however, at the cost of a higher residual adenoma rate. Further studies have to confirm to what extent polyp size and histology can determine an individualized approach. German Clinical Trials Registry (Deutsches Register Klinischer Studien), Number DRKS00025170.

Graphene Quantum Hall Effect Devices for AC and DC Electrical Metrology.

A new type of graphene-based quantum Hall standards is tested for electrical quantum metrology applications at alternating current (ac) and direct current (dc). The devices are functionalized with Cr(CO)3 to control the charge carrier density and have branched Hall contacts based on NbTiN superconducting material. The work is an in-depth study about the characteristic capacitances and related losses in the ac regime of the devices and about their performance during precision resistance measurements at dc and ac.

Self-expandable metal stents for obstructing colonic and extracolonic cancer: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2020.

The following recommendations should only be applied after a thorough diagnostic evaluation including a contrast-enhanced computed tomography (CT) scan. 1 : ESGE recommends colonic stenting to be reserved for patients with clinical symptoms and radiological signs of malignant large-bowel obstruction, without signs of perforation. ESGE does not recommend prophylactic stent placement.Strong recommendation, low quality evidence. 2 : ESGE recommends stenting as a bridge to surgery to be discussed, within a shared decision-making process, as a treatment option in patients with potentially curable left-sided obstructing colon cancer as an alternative to emergency resection.Strong recommendation, high quality evidence. 3 : ESGE recommends colonic stenting as the preferred treatment for palliation of malignant colonic obstruction.Strong recommendation, high quality evidence. 4 : ESGE suggests consideration of colonic stenting for malignant obstruction of the proximal colon either as a bridge to surgery or in a palliative setting.Weak recommendation, low quality evidence. 5 : ESGE suggests a time interval of approximately 2 weeks until resection when colonic stenting is performed as a bridge to elective surgery in patients with curable left-sided colon cancer.Weak recommendation, low quality evidence. 6 : ESGE recommends that colonic stenting should be performed or directly supervised by an operator who can demonstrate competence in both colonoscopy and fluoroscopic techniques and who performs colonic stenting on a regular basis.Strong recommendation, low quality evidence. 7 : ESGE suggests that a decompressing stoma as a bridge to elective surgery is a valid option if the patient is not a candidate for colonic stenting or when stenting expertise is not available.Weak recommendation, low quality evidence.

[German Society of Gastroenterology, Digestive and Metabolic Diseases (DGVS) position statement on endoscopic decompression in acute Ileus]. / Positionspapier der DGVS zur endoskopischen Dekompression bei akutem Ileus.

In patients with ileus with dilated intestine in imaging studies, endoscopic decompression appears a feasible option. However, its use is often uncritical and without scientific evidence. Before considering endoscopic intervention, CT-imaging should differentiate between mechanical obstruction and paralytic ileus/intestinal pseudo-obstruction. Tumor diagnosis and localisation are essential because the latter determines the choice of the decompression procedure. Coecal dilatation of more than 12 cm indicates an increased risk of perforation. In patients with toxic megacolon, dilation of the transverse colon to more than 6 cm is considered critical without much prospective evidence. Endoscopic decompression has a high complication rate and should be performed electively, and not as an emergency procedure, whenever possible. The use of CO2 insufflation rather than ambient air is strongly recommended, as is the availability of fluoroscopy. Prior trans-nasal or oral decompression-tube placement is routinely performed, and tracheobronchial intubation frequently required. In over 90 % of patients with pseudo-obstruction, conservative treatment is successful within 24 to 48 hours, and endoscopic decompression is, therefore, unnecessary. Placement of self-expanding metal stents to decompress a tumor stenosis is considered mostly for the left colon and rectum and burdened with significant risks of perforation and stent migration. Stent impact on oncological outcome is controversial because of possible tumor cell mobilization and increased postoperative cancer recurrence rates. Surgery, as primary intervention, achieves its objective in most cases. Decompression effect by endoscopic suctioning of gas and intestinal fluid is usually transient so that it is combined with transrectal decompression tubes insertion. This paper reviews the advantages and flaws of various decompression procedures in different clinical settings.

[The revised version of standard terminology in gastroenterological endoscopy - result of a consensus project of the german society for gastroenterology, digestive and metabolic diseases]. / Neufassung der Standard-Terminologie in der gastroenterologischen Endoskopie ­ Ergebnis eines Konsensusprojekts der Deutschen Gesellschaft für Gastroenterologie, Verdauungs- und Stoffwechselkrankheiten.

A uniform and comprehensive terminology is essential in the correct documentation of diagnostic or therapeutic endoscopic procedure. In the German-speaking world, the standard terminology available so far is based on a previous version published in 1999. Therefore, the German Society for Gastroenterology, Digestive and Metabolic Diseases (DGVS) has undergone a comprehensive revision and re-structuring of the terminology. This appeared mandatory due to various changes, new diagnoses and new endoscopic procedures. The suggestions drawn up by individual working groups were approved by consensus and are now available as an online document (https://doi.org/10.1055/s-0043-121167) for modifying current software systems. In order to ensure an up-to-date documentation in the future, it was decided that annual updates will be performed by the DGVS to check respective software packages for modifications and new contents.

Therapeutic lymphangiography and CT-guided sclerotherapy for the treatment of refractory lymphatic leakage.

PURPOSE: To evaluate therapeutic lymphangiography and computed tomography (CT)-guided sclerotherapy for the treatment of refractory inguinal, pelvic, abdominal, and thoracic lymphatic leakage. MATERIALS AND METHODS: Between January 2008 and April 2011, 18 patients with refractory lymphatic leakage were treated with therapeutic lymphangiography. Additionally, 10 of these 18 patients underwent CT-guided sclerotherapy with injection of ethanol at the site of the leakage. In the delayed sclerotherapy group (n = 5), the sclerotherapy procedure was performed when the leak persisted after therapeutic lymphangiography. In the immediate sclerotherapy group (n = 5), sclerotherapy was performed on the same day as lymphangiography. The sites of the lymphatic leakage were as follows: inguinal leakage in 8 patients, pelvic leakage in 4 patients, abdominal leakage in 2 patients, and thoracic leakage in 4 patients. Data collected included technical success, clinical success, and procedural complications. RESULTS: Lymphangiography was technically successful in all patients. In eight patients undergoing therapeutic lymphangiography alone, the clinical success rate was 75%, and the drainage catheter could be removed in six patients after the treatment. Lymphangiography followed by immediate sclerotherapy was clinically successful in four of five patients. Lymphangiography combined with delayed sclerotherapy was clinically successful in three of five patients. Overall, the clinical success rate was 72% (13 of 18 patients). One minor complication occurred. CONCLUSIONS: Therapeutic lymphangiography alone or in combination with CT-guided sclerotherapy is a promising treatment option for the management of refractory lymphatic leakage.

Chromoendoscopy in Combination with Random Biopsies for Patients with Pathogenic CDH1 Mutations Undergoing Endoscopic Surveillance.

OBJECTIVES: Germline mutations in the CDH1-gene are identified as the cause of 30-40% of cases of hereditary diffuse gastric cancer, an autosomal-dominant inherited cancer predisposition syndrome. Given this high risk of developing diffuse gastric cancer, carriers of a pathogenic CDH1 germline mutation are advised to undergo prophylactic gastrectomy. For patients preferring conservative management, endoscopic surveillance is recommended. The detection of diffuse gastric cancer using white light endoscopy, however, remains challenging. METHODS: Patients with pathogenic CDH1 mutation underwent (chromo)endoscopic surveillance or endoscopy prior to surgery. Biopsies were taken at suspicious sites identified by chromoendoscopy. In addition, endoscopically normal areas were assessed with mapping biopsies. Detection rates from endoscopic biopsies (mapping vs. targeted) and gastrectomy specimen were then compared. RESULT: Between 11/2015 and 12/2020, ten patients from four families with a known CDH1 germline mutation had a total of n = 24 endoscopies with n = 518 total biopsies being examined. Three patients were diagnosed with GC during the study period. These patients all had suspicious chromoendoscopic lesions (= detection rate 100%). In two of three patients who had suspicious chromoendoscopic lesions, signet cell carcinoma was also detected in mapping biopsies and multiple additional cancer foci were identified in the gastrectomy specimen. CONCLUSION: Chromoendoscopy facilitated detection of gastric carcinoma foci in CDH1 mutation carriers. Chromoendoscopy identified all patients with gastric cancer, but not all cancer foci present in these patients. We conclude that for patients opting against prophylactic total gastrectomy, the addition of chromoendoscopy to white light could be used to enhance diagnostic reliability of endoscopic surveillance.

The use of balloon-expandable stent grafts for the management of acute arterial bleeding.

PURPOSE: To evaluate the efficacy and safety of balloon-expandable stent grafts in the emergency treatment of acute arterial hemorrhage. MATERIALS AND METHODS: Between July 2008 and December 2009, 15 patients with acute arterial hemorrhage from inflammatory vessel erosion or pseudoaneurysms (n = 9), noninflammatory pseudoaneurysms (n = 3), or iatrogenic vessel injury (n = 3) were treated with emergency stent graft implants. The primary study endpoints to determine treatment efficacy and safety were survival, complication rates, and freedom from recurrent hemorrhaging or reintervention. The secondary study endpoints were technical and clinical success. RESULTS: The survival rate was 73% with a mean follow-up of 119 days ± 220. The complication rate was 20%. The procedure was technically successful in 13 of 15 (87%) patients. One endoleak persisted and led to a reintervention rate of 7%. The bleeding ceased immediately after stent graft implantation in 14 patients. CONCLUSIONS: Implantation of balloon-expandable stent grafts is a safe and effective emergency treatment for acute arterial hemorrhage from visceral and peripheral vessels.

Constrained multiple instance learning for ulcerative colitis prediction using histological images.

BACKGROUND AND OBJECTIVE: Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) affecting the colon and the rectum characterized by a remitting-relapsing course. To detect mucosal inflammation associated with UC, histology is considered the most stringent criteria. In turn, histologic remission (HR) correlates with improved clinical outcomes and has been recently recognized as a desirable treatment target. The leading biomarker for assessing histologic remission is the presence or absence of neutrophils. Therefore, the finding of this cell in specific colon structures indicates that the patient has UC activity. However, no previous studies based on deep learning have been developed to identify UC based on neutrophils detection using whole-slide images (WSI). METHODS: The methodological core of this work is a novel multiple instance learning (MIL) framework with location constraints able to determine the presence of UC activity using WSI. In particular, we put forward an effective way to introduce constraints about positive instances to effectively explore additional weakly supervised information that is easy to obtain and enjoy a significant boost to the learning process. In addition, we propose a new weighted embedding to enlarge the relevance of the positive instances. RESULTS: Extensive experiments on a multi-center dataset of colon and rectum WSIs, PICASSO-MIL, demonstrate that using the location information we can improve considerably the results at WSI-level. In comparison with prior MIL settings, our method allows for 10% improvements in bag-level accuracy. CONCLUSION: Our model, which introduces a new form of constraints, surpass the results achieved from current state-of-the-art methods that focus on the MIL paradigm. Our method can be applied to other histological concerns where the morphological features determining a positive WSI are tiny and similar to others in the image.