Active clinical trials for "Colonic Polyps"

This study is an open label, unblinded, non-randomized interventional study, comparing the investigational artificial intelligence tool with the current "gold standard": Data acquisition will be obtained during one scheduled colonoscopic procedure by a trained endoscopist. During insertion, no action will be taken, colonoscopy is performed following the standard of care. Once withdrawal is started, a second observer (not a trained endoscopist but person trained in polyp recognition) will start the bedside Artificial intelligence (AI) tool, connected to the endoscope's tower, for detection. This second observer is trained in assessing endoscopic images to define the AI tool's outcome. Due to the second observer watching the separate AI screen, the endoscopist is blinded of the AI outcome. When a detection is made by the AI system that is not recognized by the endoscopist, the endoscopist will be asked to relocate that same detection and to reassess the lesion and the possible need of therapeutic action. All detections are separately counted and categorized by the second observer. All polyp detections will be removed following standard of care for histological assessment. The entire colonoscopic procedure is recorded via a separate linked video-recorder.

Colonoscopy is the gold standard investigation in the screening of colorectal neoplasms. The investigators hypothesise that visualisation of the colonic mucosa on extubation may be improved by changing patient position as follows: left lateral position for the right colon, supine for the transverse colon and right lateral position for the left colon(fixed positioning). The investigators aim to validate our hypothesis by performing a randomised control study, comparing mucosal visualisation in patients placed in the 'routine' positions at the discretion of the endoscopist with visualisation in those placed in the above described positions. The hypothesis is that fixed positioning confers an advantage.

The purpose of this study is to evaluate the performance of a non-cathartic, computer-assisted form of CT Colonography (Virtual Colonoscopy) for detection of pre-cancerous colon polyps in a group of asymptomatic screening patients.

A prospective validation of real time deep learning artificial intelligence model for detection of missed colonic polyps

Loop formation is the most frequent cause of cecal intubation failure during colonoscopy. To reduce the loop formation, external abdominal pressure is widely used and proved to be helpful. Properly applied pressure can also decrease patients discomfort and shorten the cecal intubation time. The loop formation during water exchange is less severe as compared with during air insufflation and can be reduced quite readily. Traditionally an assistant is not asked to administer abdominal compression until the endoscopist has struggled for some time and failed to reduce the loops by withdrawal. The colonoscopist can administer the abdominal compression whenever the scope is not advancing smoothly, probably in the early stage of loop formation. We test the hypothesis that colonoscopist administered abdominal compression to remove loops in their early stage of formation hastens cecal intubation. A total of 120patients will be randomized in a 1:1 ratio (n=60 per group). When the tip of the scope doesn't advance or paradoxical movements occur, loop reduction by withdrawal of the scope will be implemented. If looping persists, abdominal compression will be applied. In the endoscopist-administered abdominal compression (endoscopist) group, the colonoscopist will apply the compression with his right hand and counter the pressure by pushing the back of the patient with his left forearm with the colonoscope in his left hand. The compression will be administered at left lower quadrant when the scope is in the sigmoid colon and at left lower quadrant and upper abdomen, respectively, when the scope tip reaches the transverse or ascending colon. If the formation of loop cannot be overcome, an assistant will apply the abdominal compression instead. In the assistant-administered abdominal compression (assistant) group, an endoscopic assistant will apply abdominal compression when a loop is formed. The assistant will apply the compression at the left lower quadrant initially, but quickly shift to other parts as needed depending on the tip location of colonoscope. If manual compressions fail, then the patients' position will be changed.

Colorectal cancer ist the 2nd most leading cancer among men and women in germany. Screening colonoscopy has the potential to detect premalignant lesions. By endoscopical resection of these lesions, colorectal cancers could be avoided. The decision for surveillance is made according to patients medical history, amount and histological characteristics of the resected polyps. Molecular guided decisions are still missing. Thus, further tools and mechanisms, beyond but in addition to endoscopy and histopathological, are strongly required to reduce such interval carcinomas and get a better and deeper inside into molecular alterations which occurs in premalignant lesions in the colon and describe risk populations which might benefit from shorter surveillance strategies by colonoscopy. Therefore GENESIS will enroll 100 patients, which underwent screening colonoscopy with polyp ectomy. All biopsies were stored and processed without formalin in special boxes (PaxGene by Qiagen®). After microdissection of polyp tissue and isolation of DNA targeted next generation sequencing of 38 cancer-related genes followed by bioinformatics and systems biology analyses. The sequencing results were correlated to the endoscopical and histopathological findings. In parallel we are collecting EDTA-blood samples for analysis of circulating cell-free DNA (cfDNA) to investigate the potential of liquid biopsies in premalignant colorectal lesions.

The purpose of this study is to compare the accuracy of using different endoscopic imaging technique (white light, white light with near focus, narrow band imaging (NBI), NBI with near focus) for detection of residual neoplastic tissue at site of prior EMR

Serrated polyposis syndrome (SPS) is the most common colorectal polyposis syndrome and is characterized by the combination of large and/or numerous serrated lesions (SLs) throughout the colorectum. SLs are classified into sessile serrated polyps (SSP) with or without dysplasia, hyperplastic polyps (HP) and traditional serrated adenomas (TSA). In 2010 the World Health Organization (WHO) defined this syndrome by any one of the following conditions: criterion I, at least 5 SLs proximal to the sigmoid colon with 2 or more of these being >10mm in size; criterion II, any SLs proximal to the sigmoid colon in a first-degree relative with SPS; criterion III, more than 20 SLs of any size distributed throughout the colon. It has been demonstrated that 11.8-28.5% of patients with SPS present with colorectal cancer (CRC) at diagnosis. Tandem colonoscopy studies have demonstrated that a significant number of lesions are missed during conventional colonoscopy. This finding is even more evident when focusing SLs where a 31% miss rate has been reported. SLs are often overlooked due to their typical appearance: flat morphology, similar colour to the surrounding mucosa, subtle and indistinctive borders. Chromoendoscopy (dye spraying onto the surface of the colon) enhances the detection of subtle and flat polyps in the colon. Until the date no studies have assessed the use of dye-based chromoendoscopy in SPS patients. The aim of this trial was to evaluate the usefulness of panchromoendoscopy with indigo carmine for the detection of polyps in the colon in patients with SPS. Secondary aims were to estimate the SLs and adenoma miss rates in these patients. Patients were randomized in a 1:1 distribution to one of the two arms of the study by a list of random numbers distributed by the coordinator center. After randomization, patients were submitted to tandem colonoscopies by the same endoscopist: In group A (HR-WLE) the first inspection was on high-resolution white-light endoscopy from the cecum/ileo-colonic anastomosis to the rectum, followed by a second inspection also on HR-WLE. In group B (HR-CE) the first inspection was on HR-WLE from the cecum/ileo-colonic anastomosis to the rectum, followed by a second inspection with panchromoendoscopy. For this, the lumen was sprayed in a segmental fashion using 0.4% indigo carmine delivered via a specially designed dye spray catheter (Olympus PW-5V1) or via the accessory channel with a 50cc syringe filled with indigo carmine and air. After allowing a few seconds for the dye to settle onto the mucosal surface, excess pools of indigo carmine were suctioned and the mucosa was then scrutinised. Time to withdrawal from the cecum was measured using a stopwatch excluding time needed for polypectomy and biopsies. Lesions detected during each inspection were described and then removed. Size (measured in comparison with an open biopsy forceps), morphology (using the Paris classification), location and polypectomy technique were recorded before removal. Histology was used as gold standard.

The adenoma detection rate by colonoscopy for asymptomatic individuals aged 50 years and older is estimated to be at least 25%. It is known that during colonoscopy, lesions may be missed. Image enhanced endoscopy techniques have been evaluated for the detection and differentiation of colonic polyps. Narrow band imaging (NBI), is one such technique. The common classification systems used predict histology is the NICE and the Sano and JNET classification. The NICE classification can be used without optical magnification; it evaluates the color of the lesion, regularity of the overlying vessels and regularity of the surface pattern. The Sano and JNET classification requires optical magnification in order to assess the capillary patterns such as whether there is dilation, irregularity or loss of irregular capillaries over the lesion. In the context of adenoma detection, the results are more contentious. A meta-analysis of randomized studies examining the utility of the first generation NBI system when compared to high definition WLI showed no difference in detection rates. A criticism of the NBI system had been the dark endoscopic view; this is a result of the optical filter, and can limit the far view. A second generation NBI system has since been developed. It is characterized by much brighter illumination despite the optical filter, and thus the far view is improved. A recent randomized controlled study compared the second-generation NBI system with high definition WLI. NBI was shown to improve polyp and adenoma detection rates compared to WLI. Blue laser imaging (BLI) is another form of narrow bandwidth imaging developed by Fujifilm Corporation (Tokyo, Japan). Instead of using an optical filter for white light to produce narrow bandwidths, the BLI system has a unique feature of illumination using two lasers and a white light phosphor to accomplish the visual enhancement of surface vessels and structures. This study aims to determine whether BLI can increase the detection rate of colonic polyps and adenomas when compared to white light endoscopy, with the null hypothesis being no difference in detection rates. This study will also examine the use of NICE and Sano/ JNET classification systems to predict histology with the BLI system.

We hypothesize that high definition narrow band imaging (NBI) colonoscopy compared to high definition white light colonoscopy will detect an increased number of nonpolypoid (flat and depressed) colorectal neoplasm.