Prospective, single-arm multicenter, international, observational postmarket study to assess the safety and efficacy of a triangulation platform for treating patients requiring endoscopic gastroplasty.

BACKGROUND AND AIMS: Gastric restriction techniques have recently emerged as minimally invasive bariatric procedures. Endoscopic sutured gastroplasty (ESG) with the Endomina (Endo Tools Therapeutics, Gosselies, Belgium) triangulation platform proved to be safe and effective for the treatment of class I and II obesity in prospective studies. In this registry, we aimed to further assess on a larger scale the safety and efficacy of the procedure in routine practice with a dedicated device. METHODS: This was a multicenter, observational, prospective post-market study including patients with obesity undergoing Endomina ESG. The primary safety outcome was the occurrence of serious adverse device effects (SADEs) at 12 months. The primary efficacy outcome was the technical success defined by completing the procedure without premature abortion owing to technical issues. The rates of procedure-related adverse events, weight loss outcomes, and quality of life changes were collected. RESULTS: A total of 142 patients underwent ESG in 3 centers from July 2020 to March 2023. Of these, 67 (mean body mass index, 38.5 ± 6.3 kg/m2) reached at least 12 months of follow-up up to October 2022. Technical success was 100%. No SADEs occurred. Seven mild procedure-related adverse events were reported overall. Mean percentage of excess weight loss and total body weight loss at 12 months' follow-up were 48.5% ± 38.6 and 15.3% ± 10.6, respectively (n = 67). Improved quality of life was observed following ESG. CONCLUSIONS: ESG is safe and effective, thus offering a satisfactory therapeutic option for a wide range of obese patients on a large scale.

American Society for Gastrointestinal Endoscopy-European Society of Gastrointestinal Endoscopy guideline on primary endoscopic bariatric and metabolic therapies for adults with obesity.

This joint ASGE-ESGE guideline provides an evidence-based summary and recommendations regarding the role of endoscopic bariatric and metabolic therapies (EBMTs) in the management of obesity. The document was developed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework. It evaluates the efficacy and safety of EBMT devices and procedures that currently have CE mark or FDA-clearance/approval, or that had been approved within five years of document development. The guideline suggests the use of EBMTs plus lifestyle modification in patients with a BMI of ≥ 30 kg/m2, or with a BMI of 27.0-29.9 kg/m2 with at least 1 obesity-related comorbidity. Furthermore, it suggests the utilization of intragastric balloons and devices for endoscopic gastric remodeling (EGR) in conjunction with lifestyle modification for this patient population.

American Society for Gastrointestinal Endoscopy-European Society of Gastrointestinal Endoscopy guideline on primary endoscopic bariatric and metabolic therapies for adults with obesity.

This joint ASGE-ESGE guideline provides an evidence-based summary and recommendations regarding the role of endoscopic bariatric and metabolic therapies (EBMTs) in the management of obesity. The document was developed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework. It evaluates the efficacy and safety of EBMT devices and procedures that currently have CE mark or FDA-clearance/approval, or that had been approved within five years of document development. The guideline suggests the use of EBMTs plus lifestyle modification in patients with a BMI of ≥30 kg/m2, or with a BMI of 27.0-29.9 kg/m2 with at least 1 obesity-related comorbidity. Furthermore, it suggests the utilization of intragastric balloons and devices for endoscopic gastric remodeling (EGR) in conjunction with lifestyle modification for this patient population.

Long-term Results of Duodeno-jejunal Bypass in the Treatment of Obesity and Type 2 Diabetes.

PURPOSE: Obesity and its related severe comorbidities are increasing rapidly. The duodenal-jejunal bypass is an endoscopically implanted device (mimicking the Roux-en-Y gastric bypass) developed to support weight reduction and improve type 2 diabetes control. MATERIALS AND METHODS: Retrospective data analysis of consecutive patients undergoing duodenal-jejunal bypass (EndoBarrier®, DJB) implantation between 2013 and 2017 was performed to evaluate safety as well as short- and long-term efficacy. RESULTS: One hundred and twenty-one patients (mean BMI of 43.1 ± 7.2 kg/m2 and weight of 138.2 ± 28.6 kg) underwent DJB implantation. The mean dwelling time was 15.5 months, the mean total body weight loss (%TBWL) after explantation was 10.3% ± 7.9% (14.2 kg, p < 0.0001), and the mean BMI was 39.5 ± 7.3 kg/m2 (p < 0.0001). There was no significant weight gain 24 months after the explantation. Seventy-seven patients had type 2 diabetes mellitus (T2DM) with a mean HbA1c before implantation of 5.6% (n = 52). The mean HbA1c after explantation was 5.1% (p = 0.0001). Significant reductions in transaminase and lipid levels before and after explantation were observed. One complication occurred during implantation and another during explantation. In 16 patients, the device had to be extracted earlier than expected (7 for severe adverse events and 9 for adverse events; 13.2%). CONCLUSION: Despite an evident rate of adverse events, the DJB shows promise as a weight-loss procedure. Our results show that some patients implanted with the device maintained reduced weight even 24 months after explantation, while many improved T2DM control.

Curriculum for diagnostic endoscopic ultrasound training in Europe: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement.

The European Society of Gastrointestinal Endoscopy (ESGE) has recognized the need to formalize and enhance training in diagnostic endoscopic ultrasound (EUS). This manuscript represents the outcome of a formal Delphi process resulting in an official Position Statement of the ESGE and provides a framework to develop and maintain skills in diagnostic EUS. This curriculum is set out in terms of the prerequisites prior to training; the recommended steps of training to a defined syllabus; the quality of training; and how competence should be defined and evidenced before independent practice. 1: Trainees should have achieved competence in upper gastrointestinal endoscopy before training in diagnostic EUS. 2: The development of diagnostic EUS skills by methods that do not involve patients is advisable, but not mandatory, prior to commencing formal training in diagnostic EUS. 3: A trainee's principal trainer should be performing adequate volumes of diagnostic EUSs to demonstrate maintenance of their own competence. 4: Training centers for diagnostic EUS should offer expertise, as well as a high volume of procedures per year, to ensure an optimal level of quality for training. Under these conditions, training centers should be able to provide trainees with a sufficient wealth of experience in diagnostic EUS for at least 12 months. 5: Trainees should engage in formal training and supplement this with a range of learning resources for diagnostic EUS, including EUS-guided fine-needle aspiration and biopsy (FNA/FNB). 6: EUS training should follow a structured syllabus to guide the learning program. 7: A minimum procedure volume should be offered to trainees during diagnostic EUS training to ensure that they have the opportunity to achieve competence in the technique. To evaluate competence in diagnostic EUS, trainees should have completed a minimum of 250 supervised EUS procedures: 80 for luminal tumors, 20 for subepithelial lesions, and 150 for pancreaticobiliary lesions. At least 75 EUS-FNA/FNBs should be performed, including mostly pancreaticobiliary lesions. 8: Competence assessment in diagnostic EUS should take into consideration not only technical skills, but also cognitive and integrative skills. A reliable valid assessment tool should be used regularly during diagnostic EUS training to track the acquisition of competence and to support trainee feedback. 9: A period of supervised practice should follow the start of independent activity. Supervision can be delivered either on site if other colleagues are already practicing EUS or by maintaining contacts with the training center and/or other EUS experts. 10: Key performance measures including the annual number of procedures, frequency of obtaining a diagnostic sample during EUS-FNA/FNB, and adverse events should be recorded within an electronic documentation system and evaluated.

Endoluminal radiofrequency ablation in patients with malignant biliary obstruction: a randomised trial.

BACKGROUND: Endoluminal radiofrequency ablation (RFA) has been promoted as palliative treatment for patients with cholangiocarcinoma (CCA) and pancreatic ductal adenocarcinoma (PDAC) in order to improve biliary drainage and eventually prolong survival. No high level evidence is, however, available on this technique. DESIGN: In this randomised controlled study, we compared endoluminal RFA plus stenting with stenting alone (control group) in patients with malignant biliary obstruction; metal stents were primarily placed. Primary outcome was overall survival; secondary outcomes were stent patency, quality of life and adverse events. In a superiority design, survival was assumed to be doubled by RFA as compared with 6.4 months in the control group (n=280). RESULTS: A total of 161 patients (male:female 90:71, mean age 71±9 years) were randomised before recruitment was terminated for futility after an interim analysis. Eighty-five patients had CCA (73 hilar, 12 distal) and 76 had pancreatic cancer. There was no difference in survival in both subgroups: for patients with CCA, median survival was 10.5 months (95% CI 6.7 to 18.3) in the RFA group vs 10.6 months (95% CI 9.0 to 24.8), p=0.58)) in the control group. In the subgroup with pancreatic cancer, median survival was 6.4 months (95% CI 4.3 to 9.7) for the RFA vs 7.7 months (95% CI 5.6 to 11.3), p=0.73) for the control group. No benefit was seen in the RFA group with regard to stent patency (at 12 months 40% vs 36% in CCA and 66% vs 65% in PDAC), and quality of life was unchanged by either treatment and comparable between the groups. Adverse events occurred in seven patients in each groups. CONCLUSION: A combination of endoluminal RFA and stenting was not superior to stenting alone in prolonging survival or improving stent patency in patients with malignant biliary obstruction. TRIAL REGISTRATION NUMBER: NCT03166436.

A Fecal MicroRNA Signature by Small RNA Sequencing Accurately Distinguishes Colorectal Cancers: Results From a Multicenter Study.

BACKGROUND & AIMS: Fecal tests currently used for colorectal cancer (CRC) screening show limited accuracy in detecting early tumors or precancerous lesions. In this respect, we comprehensively evaluated stool microRNA (miRNA) profiles as biomarkers for noninvasive CRC diagnosis. METHODS: A total of 1273 small RNA sequencing experiments were performed in multiple biospecimens. In a cross-sectional study, miRNA profiles were investigated in fecal samples from an Italian and a Czech cohort (155 CRCs, 87 adenomas, 96 other intestinal diseases, 141 colonoscopy-negative controls). A predictive miRNA signature for cancer detection was defined by a machine learning strategy and tested in additional fecal samples from 141 CRC patients and 80 healthy volunteers. miRNA profiles were compared with those of 132 tumors/adenomas paired with adjacent mucosa, 210 plasma extracellular vesicle samples, and 185 fecal immunochemical test leftover samples. RESULTS: Twenty-five miRNAs showed altered levels in the stool of CRC patients in both cohorts (adjusted P < .05). A 5-miRNA signature, including miR-149-3p, miR-607-5p, miR-1246, miR-4488, and miR-6777-5p, distinguished patients from control individuals (area under the curve [AUC], 0.86; 95% confidence interval [CI], 0.79-0.94) and was validated in an independent cohort (AUC, 0.96; 95% CI, 0.92-1.00). The signature classified control individuals from patients with low-/high-stage tumors and advanced adenomas (AUC, 0.82; 95% CI, 0.71-0.97). Tissue miRNA profiles mirrored those of stool samples, and fecal profiles of different gastrointestinal diseases highlighted miRNAs specifically dysregulated in CRC. miRNA profiles in fecal immunochemical test leftover samples showed good correlation with those of stool collected in preservative buffer, and their alterations could be detected in adenoma or CRC patients. CONCLUSIONS: Our comprehensive fecal miRNome analysis identified a signature accurately discriminating cancer aimed at improving noninvasive diagnosis and screening strategies.

Periprocedural safety profile of peroral endoscopic myotomy (POEM)-a retrospective analysis of adverse events according to two different classifications.

BACKGROUND: Peroral endoscopic myotomy (POEM) is nowadays a standard method for treatment of achalasia; nevertheless, it remains an invasive intervention with corresponding risk of adverse events (AEs). The classification and grading of AEs are still a matter of discussion. The aim of our retrospective study was to assess the occurrence of all "undesirable" events and "true" adverse events in patients undergoing POEM and to compare the outcomes when either Clavien-Dindo classification (CDC) or American Society of Gastrointestinal Endoscopy (ASGE) lexicon classification applied. METHODS: This was a retrospective analysis of prospectively managed database of all patients who had undergone POEM between December 2012 and August 2018. We assessed the pre-, peri-, and early-postoperative (up to patient's discharge) undesirable events (including those not fulfilling criteria for AEs) and "true" AEs according the definition in either of the classifications. RESULTS: A total of 231 patients have successfully undergone 244 POEM procedures (13 × re-POEM). Twenty-nine procedures (11.9%) passed uneventfully, while in 215 procedures (88.1%), a total of 440 undesirable events occurred. The CDC identified 27 AEs (17 minor, 10 major) occurring in 23/244 (9.4%) procedures. The ASGE lexicon identified identical 27 AEs (21 mild or moderate, 6 severe or fatal) resulting in the severity distribution of AEs being the only difference between the two classifications. Only the absence of previous treatment was found to be a risk factor [p = 0.047, OR with 95% CI: 4.55 (1.02; 20.25)] in the combined logistic regression model. CONCLUSION: Undesirable events are common in patients undergoing POEM but the incidence of true AEs is low according to both classifications. Severe adverse events are infrequent irrespective of the classification applied. CDC may be more appropriate than ASGE lexicon for classifying POEM-related AEs given a surgical nature of this procedure.

Acute Pancreatitis in Patients After Liver Transplantation.

BACKGROUND Acute pancreatitis (AP) is a relatively rare but serious complication that can occur after organ transplantation. MATERIAL AND METHODS The aim of this study was to evaluate the incidence, potential risk factors, and course of AP in patients following liver transplantation at a single large-volume transplant center. RESULTS Out of a total of 1850 transplanted patients, 49 (2.8%) were diagnosed with AP. Of this group, 37 (75.5%) had a mild form of AP and 12 (24.5%) had a severe form of AP. The mortality rate was 10% overall and 42% in the group of patients with severe AP. An early form of AP (<30 days from transplantation) occurred in 13 patients (26.5%), most of whom presented with severe AP (10 patients, 76.9%); 4 patients died (40%). A late form of AP was diagnosed in 36 patients (73.5%), most of whom had mild AP (34 patients, 94.4%); 1 of 2 patients with severe AP died. The most common AP etiologies were post-ERCP (38.8%), idiopathic (34.7%), and postoperative (18.4%). Chronic HBV infection was a risk factor for development of AP (P=0.01). CONCLUSIONS AP in liver transplant recipients was more frequent and more severe than in the general population. This unfavorable course was associated with the occurrence of AP in the early post-transplant period. Liver transplantation due to complications of HBV infection was a risk factor for the development of AP.

Endoscopic diagnosis and management of esophagogastric variceal hemorrhage: European Society of Gastrointestinal Endoscopy (ESGE) Guideline.

1: ESGE recommends that patients with compensated advanced chronic liver disease (ACLD; due to viruses, alcohol, and/or nonobese [BMI < 30 kg/m2] nonalcoholic steatohepatitis) and clinically significant portal hypertension (hepatic venous pressure gradient [HVPG] > 10 mmHg and/or liver stiffness by transient elastography > 25 kPa) should receive, if no contraindications, nonselective beta blocker (NSBB) therapy (preferably carvedilol) to prevent the development of variceal bleeding.Strong recommendation, moderate quality evidence. 2: ESGE recommends that in those patients unable to receive NSBB therapy with a screening upper gastrointestinal (GI) endoscopy that demonstrates high risk esophageal varices, endoscopic band ligation (EBL) is the endoscopic prophylactic treatment of choice. EBL should be repeated every 2-4 weeks until variceal eradication is achieved. Thereafter, surveillance EGD should be performed every 3-6 months in the first year following eradication.Strong recommendation, moderate quality evidence. 3: ESGE recommends, in hemodynamically stable patients with acute upper GI hemorrhage (UGIH) and no history of cardiovascular disease, a restrictive red blood cell (RBC) transfusion strategy, with a hemoglobin threshold of ≤ 70 g/L prompting RBC transfusion. A post-transfusion target hemoglobin of 70-90 g/L is desired.Strong recommendation, moderate quality evidence. 4 : ESGE recommends that patients with ACLD presenting with suspected acute variceal bleeding be risk stratified according to the Child-Pugh score and MELD score, and by documentation of active/inactive bleeding at the time of upper GI endoscopy.Strong recommendation, high quality of evidence. 5 : ESGE recommends the vasoactive agents terlipressin, octreotide, or somatostatin be initiated at the time of presentation in patients with suspected acute variceal bleeding and be continued for a duration of up to 5 days.Strong recommendation, high quality evidence. 6 : ESGE recommends antibiotic prophylaxis using ceftriaxone 1 g/day for up to 7 days for all patients with ACLD presenting with acute variceal hemorrhage, or in accordance with local antibiotic resistance and patient allergies.Strong recommendation, high quality evidence. 7 : ESGE recommends, in the absence of contraindications, intravenous erythromycin 250 mg be given 30-120 minutes prior to upper GI endoscopy in patients with suspected acute variceal hemorrhage.Strong recommendation, high quality evidence. 8 : ESGE recommends that, in patients with suspected variceal hemorrhage, endoscopic evaluation should take place within 12 hours from the time of patient presentation provided the patient has been hemodynamically resuscitated.Strong recommendation, moderate quality evidence. 9 : ESGE recommends EBL for the treatment of acute esophageal variceal hemorrhage (EVH).Strong recommendation, high quality evidence. 10 : ESGE recommends that, in patients at high risk for recurrent esophageal variceal bleeding following successful endoscopic hemostasis (Child-Pugh C  ≤ 13 or Child-Pugh B > 7 with active EVH at the time of endoscopy despite vasoactive agents, or HVPG > 20 mmHg), pre-emptive transjugular intrahepatic portosystemic shunt (TIPS) within 72 hours (preferably within 24 hours) must be considered.Strong recommendation, high quality evidence. 11 : ESGE recommends that, for persistent esophageal variceal bleeding despite vasoactive pharmacological and endoscopic hemostasis therapy, urgent rescue TIPS should be considered (where available).Strong recommendation, moderate quality evidence. 12 : ESGE recommends endoscopic cyanoacrylate injection for acute gastric (cardiofundal) variceal (GOV2, IGV1) hemorrhage.Strong recommendation, high quality evidence. 13: ESGE recommends endoscopic cyanoacrylate injection or EBL in patients with GOV1-specific bleeding.Strong recommendations, moderate quality evidence. 14: ESGE suggests urgent rescue TIPS or balloon-occluded retrograde transvenous obliteration (BRTO) for gastric variceal bleeding when there is a failure of endoscopic hemostasis or early recurrent bleeding.Weak recommendation, low quality evidence. 15: ESGE recommends that patients who have undergone EBL for acute EVH should be scheduled for follow-up EBLs at 1- to 4-weekly intervals to eradicate esophageal varices (secondary prophylaxis).Strong recommendation, moderate quality evidence. 16: ESGE recommends the use of NSBBs (propranolol or carvedilol) in combination with endoscopic therapy for secondary prophylaxis in EVH in patients with ACLD.Strong recommendation, high quality evidence.

Discovery of Long Non-Coding RNA MALAT1 Amplification in Precancerous Colorectal Lesions.

A colorectal adenoma, an aberrantly growing tissue, arises from the intestinal epithelium and is considered as precursor of colorectal cancer (CRC). In this study, we investigated structural and numerical chromosomal aberrations in adenomas, hypothesizing that chromosomal instability (CIN) occurs early in adenomas. We applied array comparative genomic hybridization (aCGH) to fresh frozen colorectal adenomas and their adjacent mucosa from 16 patients who underwent colonoscopy examination. In our study, histologically similar colorectal adenomas showed wide variability in chromosomal instability. Based on the obtained results, we further stratified patients into four distinct groups. The first group showed the gain of MALAT1 and TALAM1, long non-coding RNAs (lncRNAs). The second group involved patients with numerous microdeletions. The third group consisted of patients with a disrupted karyotype. The fourth group of patients did not show any CIN in adenomas. Overall, we identified frequent losses in genes, such as TSC2, COL1A1, NOTCH1, MIR4673, and GNAS, and gene gain containing MALAT1 and TALAM1. Since long non-coding RNA MALAT1 is associated with cancer cell metastasis and migration, its gene amplification represents an important event for adenoma development.

Impact of Endoluminal Radiofrequency Ablation on Immunity in Pancreatic Cancer and Cholangiocarcinoma.

Radiofrequency ablation (RFA) is a mini-invasive loco-regional ablation technique that is increasingly being used as a palliative treatment for pancreatic cancer and cholangiocarcinoma. Ablation-triggered immune system stimulation has been proposed as a mechanism behind the systemic effects of RFA. The aim of our study was to investigate the immune response to endoluminal biliary RFA. Peripheral blood samples were collected from patients with pancreatic cancer and cholangiocarcinoma randomised to receive endoluminal biliary radiofrequency ablation + stent (19 patients) or stent only (21 patients). We observed an early increase in IL-6 levels and a delayed increase in CXCL1, CXCL5, and CXCL11 levels as well as an increase in CD8+ and NK cells. However, these changes were not specific to RFA treatment. Explicitly in response to RFA, we observed a delayed increase in serum CXCL1 levels and an early decrease in the number of anti-inflammatory CD206+ blood monocytes. Our study provides the first evidence of endoluminal biliary RFA-based regulation of the systemic immune response in patients with pancreatic cancer and cholangiocarcinoma. These changes were characterised by a general inflammatory response. RFA-specific activation of the adaptive immune system was not confirmed.

Biliary obstruction following transjugular intrahepatic portosystemic shunt placement in a patient after liver transplantation: A case report.

BACKGROUND: Transjugular intrahepatic portosystemic shunt (TIPS) is a method used to decrease portal hypertension. Biliary stricture is the rarest of the complications associated with this procedure with only 12 cases previously reported in the literature. None of these cases have documented the resolution of biliary stenosis induced by a stent graft. The only curative solutions reported are liver transplantation or bypassing the stenosis with an artificial biliary tract using advanced endoscopic techniques. CASE SUMMARY: This is the first reported case of biliary obstruction secondary to TIPS placement in a transplanted liver. In our patient, a portosystemic shunt was created to treat severe veno-occlusive liver graft disease manifesting itself primarily by fluid retention. A cholestatic liver lesion and cholangitis with abscesses developed due to a stent graft-induced stricture in the dorsal segment of the right hepatic duct and the stricture diminished following percutaneous drainage. Endoscopic drainage was performed after unsuccessful removal of the percutaneous catheter resulting in a bilio-cutaneous fistula. Although the liver graft now functions well, the stricture remains refractory even after 44 mo of treatment. CONCLUSION: Biliary strictures caused by TIPS in both transplanted and native livers seem refractory to endoscopic treatment.

Therapeutic endoscopic ultrasound: European Society of Gastrointestinal Endoscopy (ESGE) Technical Review.

1: ESGE recommends a prolonged course of a prophylactic broad-spectrum antibiotic in patients with ascites who are undergoing therapeutic endoscopic ultrasound (EUS) procedures.Strong recommendation, low quality evidence. 2: ESGE recommends placement of partially or fully covered self-expandable metal stents during EUS-guided hepaticogastrostomy for biliary drainage in malignant disease.Strong recommendation, moderate quality evidence. 3: ESGE recommends EUS-guided pancreatic duct (PD) drainage should only be performed in high volume expert centers, owing to the complexity of this technique and the high risk of adverse events.Strong recommendation, low quality evidence. 4: ESGE recommends a stepwise approach to EUS-guided PD drainage in patients with favorable anatomy, starting with rendezvous-assisted endoscopic retrograde pancreatography (RV-ERP), followed by antegrade or transmural drainage only when RV-ERP fails or is not feasible.Strong recommendation, low quality evidence. 5: ESGE suggests performing transduodenal EUS-guided gallbladder drainage with a lumen-apposing metal stent (LAMS), rather than using the transgastric route, as this may reduce the risk of stent dysfunction.Weak recommendation, low quality evidence. 6: ESGE recommends using saline instillation for small-bowel distension during EUS-guided gastroenterostomy.Strong recommendation, low quality evidence. 7: ESGE recommends the use of saline instillation with a 19G needle and an electrocautery-enhanced LAMS for EUS-directed transgastric endoscopic retrograde cholangiopancreatography (EDGE) procedures.Strong recommendation, low quality evidence. 8: ESGE recommends the use of either 15- or 20-mm LAMSs for EDGE, with a preference for 20-mm LAMSs when considering a same-session ERCP.Strong recommendation, low quality evidence.

Mutational analysis of driver genes defines the colorectal adenoma: in situ carcinoma transition.

A large proportion of colorectal carcinomas (CRC) evolve from colorectal adenomas. However, not all individuals with colonic adenomas have a risk of CRC substantially higher than those of the general population. The aim of the study was to determine the differences or similarities of mutation profile among low- and high-grade adenomas and in situ carcinoma with detailed follow up. We have investigated the mutation spectrum of well-known genes involved in CRC (such as APC, BRAF, EGFR, NRAS, KRAS, PIK3CA, POLE, POLD1, SMAD4, PTEN, and TP53) in a large, well-defined series of 96 adenomas and in situ carcinomas using a high-throughput genotyping technique. Besides, the microsatellite instability and APC and MLH1 promoter methylation were studied as well. We observed a high frequency of pathogenic variants in the studied genes. The APC, KRAS and TP53 mutation frequencies were slightly lower in adenoma samples than in in situ carcinoma samples. Further, when we stratified mutation frequency based on the grade, the frequency distribution was as follows: low-grade adenoma-high-grade adenomas-in situ carcinoma: APC gene 42.9-56.0-54.5%; KRAS gene 32.7-32.0-45.5%; TP53 gene 8.2-20.0-18.2%. The occurrence of KRAS mutation was associated with the presence of villous histology and methylation of the APC promoter was significantly associated with the presence of POLE genetic variations. However, no association was noticed with the presence of any singular mutation and occurrence of subsequent adenoma or CRC. Our data supports the multistep model of gradual accumulation of mutations, especially in the driver genes, such as APC, TP53 and KRAS.