Performance of Faecal Immunochemical Testing for Colorectal Cancer Screening at Varying Positivity Thresholds.

BACKGROUND: The positivity thresholds of faecal immunochemical testing (FIT) in colorectal cancer (CRC) screening vary between countries. AIMS: To explore the trade-off between colonoscopies performed, adverse events and lesions detected at different FIT thresholds in a Norwegian CRC screening trial. METHODS: We included first participation in biennial FIT screening for 47,265 individuals aged 50-74 years. Individuals with FIT > 15 µg Hb/g faeces were referred for colonoscopy. We estimated the number of colonoscopies, adverse events, screen-detected CRCs, advanced adenomas and serrated lesions expected at FIT thresholds currently or recently used in other European countries ranging between 20 and 150 µg/g. RESULTS: At the 15 µg/g threshold (Norway), 3705 participants underwent colonoscopy, of whom 203 had CRC, 1119 advanced adenomas and 256 advanced serrated lesions. Using a 47 µg/g threshold, 1826 (49.3%) individuals would have undergone colonoscopy, and 154 (75.9%) would have been diagnosed with CRC, 702 (62.7%) with advanced adenoma and 128 (50.0%) with advanced serrated lesion compared to the 15 µg/g threshold. At 150 µg/g, the corresponding figures would have been 838 (22.6%) undergoing colonoscopy, 114 (56.2%) with CRC, 345 (30.8%) advanced adenoma and 54 (21.1%) advanced serrated lesions. The detection rate of stage I CRC was 0.22% at 15 µg/g and 0.11% at 150 µg/g. Post-colonoscopy bleeding rates were 0.8% and 1.7%, respectively. CONCLUSIONS: Increasing the FIT threshold reduces colonoscopy demand, but substantially decreases lesion detection and unfavourably changes CRC stage distribution. The risk of adverse events at colonoscopy increased with FIT threshold, requiring country-specific information on adverse events. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT01538550.

QUAIDE - Quality assessment of AI preclinical studies in diagnostic endoscopy.

Artificial intelligence (AI) holds significant potential for enhancing quality of gastrointestinal (GI) endoscopy, but the adoption of AI in clinical practice is hampered by the lack of rigorous standardisation and development methodology ensuring generalisability. The aim of the Quality Assessment of pre-clinical AI studies in Diagnostic Endoscopy (QUAIDE) Explanation and Checklist was to develop recommendations for standardised design and reporting of preclinical AI studies in GI endoscopy.The recommendations were developed based on a formal consensus approach with an international multidisciplinary panel of 32 experts among endoscopists and computer scientists. The Delphi methodology was employed to achieve consensus on statements, with a predetermined threshold of 80% agreement. A maximum three rounds of voting were permitted.Consensus was reached on 18 key recommendations, covering 6 key domains: data acquisition and annotation (6 statements), outcome reporting (3 statements), experimental setup and algorithm architecture (4 statements) and result presentation and interpretation (5 statements). QUAIDE provides recommendations on how to properly design (1. Methods, statements 1-14), present results (2. Results, statements 15-16) and integrate and interpret the obtained results (3. Discussion, statements 17-18).The QUAIDE framework offers practical guidance for authors, readers, editors and reviewers involved in AI preclinical studies in GI endoscopy, aiming at improving design and reporting, thereby promoting research standardisation and accelerating the translation of AI innovations into clinical practice.

Prediction of metachronous advanced colorectal neoplasia by KRAS mutation in polyps.

BACKGROUND: The potential of molecular markers in the removed polys as reliable predictors of metachronous lesions is still uncertain. AIM: Our aim was to evaluate the role of somatic mutations in KRAS in polyps of patients with high-risk adenomas to predict the risk of advanced polyps or colorectal cancer (CRC) within 3 years. METHODS: A total of 518 patients were prospectively enrolled. The included patients had adenomas ≥10 mm, high-grade dysplasia, villous component or ≥3 more adenomas at baseline and were scheduled to undergo surveillance colonoscopy at 3 years ± 6 months. Somatic KRAS mutation was performed on 1189 polyps collected from these patients. At surveillance, advanced lesions were defined as adenomas with a size of ≥10 mm. High-grade dysplasia or villous component, serrated polyps ≥10 mm or with dysplasia or CRC. RESULTS: At baseline, 81 patients (15.6%) had KRAS mutations in at least one polyp. Patients with KRAS mutated polyps had more frequent villous histological lesions and size ≥20 mm. In the multivariate analysis, adjusted for age and sex, only age (odds ratios [OR], 1.06; 95% confidence interval [CI], 1.02-1.09; p < 0.001), ≥5 adenomas (OR, 3.92; 95% CI, 1.96-7.82), and KRAS mutation (OR, 2.54; 95% CI, 1.48-4.34; p < 0.01) were independently associated with the development of advanced lesions at surveillance. CONCLUSIONS: Our results show that, in patients with high-risk adenomas, the presence of somatic mutations in KRAS is an independent risk factor for the development of advanced metachronous polyps.

Adverse events after colonoscopy in a randomised colorectal cancer screening trial.

OBJECTIVE: Colonoscopy-related adverse events increase the burden of colorectal cancer (CRC) screening. This cross-sectional study evaluates adverse events during and after colonoscopy in a large, randomised CRC screening trial in Norway comparing sigmoidoscopy to immunochemical testing for faecal blood. METHODS: We included all individuals who underwent colonoscopy at two screening centres between 2012 and 2020. From medical records, we retrieved data on adverse events during and within 30 days after colonoscopy and classified them according to the American Society for Gastrointestinal Endoscopy lexicon for endoscopic adverse events. Multivariable logistic regression models were fitted to identify risk factors for adverse events. RESULTS: Of the 10 244 included individuals, 242 (2.4%) had at least one adverse event that was possibly, probably, or definitively related to the colonoscopy. 188 (1.8%) had mild adverse events, 50 (0.49%) had moderate, 3 (0.03%) had severe, and 1 had a fatal adverse event. The most frequent adverse events were lower gastrointestinal bleeding (0.86%), abdominal pain (0.48%), vasovagal reaction (0.39%), postpolypectomy syndrome (0.20%), and perforation (0.08%). 23 (0.22%) individuals had non-gastrointestinal adverse events. Risk factors associated with adverse events were older age, female sex, screening centre, anticoagulant therapy, number of polypectomies, size of lesion removed, presence of proximal lesion, and adenocarcinoma. Adverse event rates per endoscopist ranged from 0% to 4.9%. CONCLUSION: Adverse events after colonoscopy of screening positives occurred in about 2 out of 100 procedures. Three-quarters of events were mild. Awareness of risk factors may help endoscopists to mitigate the risk. TRIAL REGISTRATION NUMBER: NCT01538550.

Surgical treatment of benign colorectal polyps 2008-21. / Kirurgisk behandling av benigne kolorektale polypper 2008­21.

Background: Colorectal cancer is one of the most common forms of cancer in Norway, and typically develops from colorectal polyps. For benign colorectal polyps, endoscopic removal is recommended to avoid unnecessary surgery. This study identifies the extent of surgical treatment of benign polyps in the period 1 January 2008-31 December 2021. Material and method: We obtained statistics from the Norwegian Patient Registry on the surgical resection of benign colorectal polyps, number of colonoscopies performed and number of patients with the diagnostic code for benign polyp in the study period. Population size from Statistics Norway was used to calculate annual incidences of the procedure. Results: The number of patients with benign polyps increased from 211 per 100 000 population to 444 per 100 000 during the study period. The number of colonoscopies increased from 9.4 per 1 000 population to 16.7 per 1 000. The number of surgical resections of benign colorectal polyps per year increased from 4.2 per 100 000 population to 6.3 per 100 000. The total number of unique patients with benign polyps in the period was 215 736, of which 2.1 % received surgical treatment, with the figures varying from 2.0 % in 2008 to 1.6 % in 2021. Interpretation: Our results show that surgical treatment of benign polyps is still widespread in Norway. This impacts on patient safety and health economics. We propose the establishment of multidisciplinary teams and enhanced endoscopic competence in Norwegian health trusts.

Risk factors for metachronous colorectal cancer or advanced lesions after endoscopic resection of serrated polyps: a systematic review and meta-analysis.

BACKGROUND AND AIMS: Serrated polyps (SPs) are precursors to 15% to 20% of colorectal cancers (CRCs). However, there are uncertainties regarding which SPs require surveillance and at what intervals, with recommendations adapted from those for adenomas in the absence of solid evidence. Our aim was to assess which SP risk characteristics relate to a higher risk of metachronous CRC or advanced polyps. METHODS: We systematically searched PubMed, Embase, and Cochrane for cohort studies, case-control studies, and clinical trials from inception to December 31, 2023, of CRC or advanced polyps (advanced adenoma [AA] or advanced SP) incidence at surveillance stratified by baseline SP size, dysplasia, location, and multiplicity. We defined advanced SPs as those ≥10 mm or with dysplasia. CRC and advanced polyp incidence per 1000 person-years were estimated. We performed a meta-analysis by calculating pooled relative risks (RRs) using a random-effects model. RESULTS: A total of 5903 studies were reviewed, and 14 were included with 493,949 patients (mean age, 59.5 years; 55% men). The mean follow-up was 4.9 years. CRC incidence per 1000 person-years was 2.09 (95% confidence interval [CI], 1.29-2.90) for advanced SPs, 1.52 (95% CI, 0.78-2.25) for SPs of ≥10 mm, 5.86 (95% CI, 2.16-9.56) for SPs with dysplasia, 1.18 (95% CI, 0.77-1.60) for proximal SPs, 0.52 (95% CI, 0.08-1.12) for ≥3 SPs, 0.50 (95% CI, 0.35-0.66) for nonadvanced SPs, and 0.44 (95% CI, 0.41-0.46) for normal colonoscopy findings. Metachronous CRC risk was higher in advanced SPs versus nonadvanced SPs (RR, 1.84; 95% CI, 1.11-3.04) and versus normal colonoscopy findings (RR, 2.92; 95% CI, 2.26-3.77), in SPs of ≥10 mm versus <10 mm (RR, 2.61; 95% CI, 1.43-4.77) and versus normal colonoscopy findings (RR: 3.52; 95% CI, 2.17-5.69); and in SPs with dysplasia versus normal colonoscopy findings (RR: 2.71; 95% CI, 2.00-3.67). No increase in CRC or advanced polyp risk was found in patients with proximal versus distal SPs, nor in ≥3 SPs versus 1 or 2 SPs. CONCLUSIONS: CRC risk is significantly higher in patients with baseline advanced SPs after 4.9 years of follow-up, with risk magnitudes similar to those described for AA, supporting the current recommendation for 3-year surveillance in patients with advanced SPs.

Impact of inadequate bowel cleansing in sigmoidoscopy screening.

BACKGROUND AND STUDY AIMS: Long-time follow-up of sigmoidoscopy screening trials has shown reduced incidence and mortality of colorectal cancer (CRC), but inadequate bowel cleansing may hamper efficacy. The aim of this study was to assess the impact of bowel cleansing quality in sigmoidoscopy screening. PATIENTS AND METHODS: Individuals 50 to 74 years old who had a screening sigmoidoscopy in a population-based Norwegian, randomized trial between 2012 and 2019, were included in this cross-sectional study. The bowel cleansing quality was categorised as excellent, good, partly poor, or poor. The effect of bowel cleansing quality on adenoma detection rate (ADR) and referral to colonoscopy was evaluated by fitting multivariable logistic regression models. RESULTS: 35,710 individuals were included. The bowel cleansing at sigmoidoscopy was excellent in 20,934 (58.6%) individuals, good in 6580 (18.4%), partly poor in 7097 (19.9%) and poor in 1099 (3.1%). The corresponding ADRs were 17.0%, 16.6%, 14.5%, and 13.0%. Compared to participants with excellent bowel cleansing, those with poor bowel cleansing had an odds ratio for adenoma detection of 0.66 (95% confidence interval 0.55-0.79). We found substantial differences in the assessment of bowel cleansing quality among endoscopists. CONCLUSIONS: Inadequate bowel cleansing reduces the efficacy of sigmoidoscopy screening, by lowering ADR. A validated rating scale and improved bowel preparation are needed to make sigmoidoscopy an appropriate screening method.Trial registration Clinicaltrials.gov (NCT01538550).

Dramatic improvements in outcome following pancreatoduodenectomy for pancreatic and periampullary cancers.

BACKGROUND: Pancreatoduodenectomy is the only cure for cancers of the pancreas and the periampullary region but has considerable operative complications and uncertain prognosis. Our goal was to analyse temporal improvements and provide contemporary population-based benchmarks for outcomes following pancreatoduodenectomy. METHODS: We empanelled a cohort comprising all patients in Sweden with pancreatic or periampullary cancer treated with pancreatoduodenectomy from 1964 to 2016 and achieved complete follow-up through 2016. We analysed postoperative deaths and disease-specific net survival. RESULTS: We analysed 5923 patients with cancer of the pancreas (3876), duodenum (444), bile duct (504), or duodenal papilla (963) who underwent classic (3332) or modified (1652) Whipple's procedure or total pancreatectomy (803). Postoperative deaths declined from 17.2% in the 1960s to 1.6% in the contemporary time period (2010-2016). For all four cancer types, median, 1-year and 5-year survival improved substantially over time. Among patients operated between 2010 and 2016, 5-year survival was 29.0% (95% confidence interval (CI): 25.5, 33.0) for pancreatic cancer, 71.2% (95% CI: 62.9, 80.5) for duodenal cancer, 30.8% (95% CI: 23.0, 41.3) for bile duct cancer, and 62.7% (95% CI: 55.5, 70.8) for duodenal papilla cancer. CONCLUSION: There is a continuous and substantial improvement in the benefit-harm ratio after pancreatoduodenectomy for cancer.

Gastroenterology/Hepatology: What You May Have Missed in 2023.

This article summarizes clinically important gastroenterology developments from 2023 for internal medicine specialists. In colorectal cancer screening, a new RNA fecal screening test is on the horizon, as well as a new analysis on the benefits of using artificial intelligence in screening colonoscopy to detect more polyps. There is new evidence for management of gastrointestinal bleeding, a new drug for treatment of recurrent small-intestinal angiodysplasia, and a new endoscopic treatment method in patients with gastrointestinal tumor bleeding. The authors feature a randomized trial about amitriptyline as treatment for patients with irritable bowel syndrome by primary care providers and bring you news about new biologic agents for inflammatory bowel disease and eosinophilic esophagitis. Finally, they review 2 important articles on new terminology and management of metabolic dysfunction-associated fatty liver disease.

Effectiveness of Colonoscopy Screening vs Sigmoidoscopy Screening in Colorectal Cancer.

Importance: Randomized clinical screening trials have shown that sigmoidoscopy screening reduces colorectal cancer (CRC) incidence and mortality. Colonoscopy has largely replaced sigmoidoscopy for CRC screening, but long-term results from randomized trials on colonoscopy screening are still lacking. Objective: To estimate the additional screening benefit of colonoscopy compared with sigmoidoscopy. Design, Setting, and Participants: This comparative effectiveness simulation study pooled data on 358 204 men and women randomly assigned to sigmoidoscopy screening or usual care in 4 randomized sigmoidoscopy screening trials conducted in Norway, Italy, the US, and UK with inclusion periods in the years 1993 to 2001. The primary analysis of the study was conducted from January 19 to December 30, 2021. Intervention: Invitation to endoscopic screening. Main Outcomes and Measures: Primary outcomes were CRC incidence and mortality. Using pooled 15-year follow-up data, colonoscopy screening effectiveness was estimated assuming that the efficacy of colonoscopy in the proximal colon was similar to that observed in the distal colon in the sigmoidoscopy screening trials. The simulation model was validated using data from Norwegian participants in a colonoscopy screening trial. Results: This analysis included 358 204 individuals (181 971 women [51%]) aged 55 to 64 years at inclusion with a median follow-up time ranging from 15 to 17 years. Compared with usual care, colonoscopy prevented an estimated 50 (95% CI, 42-58) CRC cases per 100 000 person-years, corresponding to 30% incidence reduction (rate ratio, 0.70 [95% CI, 0.66-0.75]), and prevented an estimated 15 (95% CI, 11-19) CRC deaths per 100 000 person-years, corresponding to 32% mortality reduction (rate ratio, 0.68 [95% CI, 0.61-0.76]). The additional benefit of colonoscopy screening compared with sigmoidoscopy was 12 (95% CI, 10-14) fewer CRC cases and 4 (95% CI, 3-5) fewer CRC deaths per 100 000 person-years, corresponding to percentage point reductions of 6.9 (95% CI, 6.0-7.9) for CRC incidence and 7.6 (95% CI, 5.7-9.6) for CRC mortality. The number needed to switch from sigmoidoscopy to colonoscopy screening was 560 (95% CI, 486-661) to prevent 1 CRC case and 1611 (95% CI, 1275-2188) to prevent 1 CRC death. Conclusions and Relevance: The findings of this comparative effectiveness study assessing long-term follow-up after CRC screening suggest that there was an additional preventive effect on CRC incidence and mortality associated with colonoscopy screening compared with sigmoidoscopy screening, but the additional preventive effect was less than what was achieved by introducing sigmoidoscopy screening where no screening existed. The results probably represent the upper limit of what may be achieved with colonoscopy screening compared with sigmoidoscopy screening.