This analysis of Norwegian registry data suggests that colonoscopic surveillance during the 8 years after removal of low-risk adenomas is not required for a reduction in colorectal-cancer mortality.
...Screening programs for colorectal cancer are currently implemented in many Western populations
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because randomized trials have documented an association between screening and a sustained reduction in colorectal-cancer mortality.
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The benefit is most likely due to early detection of cancer, endoscopic removal of adenomas, and surveillance of patients who are considered to be at high risk for the development of new neoplastic lesions.
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However, precise quantification of the risk of death from cancer after adenoma removal has been hampered by the scarceness of large, population-based studies with long follow-up periods.
Previous studies were performed in populations undergoing intensive surveillance, . . .
Artificial intelligence (AI)-based polyp detection systems are used during colonoscopy with the aim of increasing lesion detection and improving colonoscopy quality.
We performed a systematic review ...and meta-analysis of prospective trials to determine the value of AI-based polyp detection systems for detection of polyps and colorectal cancer. We performed systematic searches in MEDLINE, EMBASE, and Cochrane CENTRAL. Independent reviewers screened studies and assessed eligibility, certainty of evidence, and risk of bias. We compared colonoscopy with and without AI by calculating relative and absolute risks and mean differences for detection of polyps, adenomas, and colorectal cancer.
Five randomized trials were eligible for analysis. Colonoscopy with AI increased adenoma detection rates (ADRs) and polyp detection rates (PDRs) compared to colonoscopy without AI (values given with 95 %CI). ADR with AI was 29.6 % (22.2 % - 37.0 %) versus 19.3 % (12.7 % - 25.9 %) without AI; relative risk (RR 1.52 (1.31 - 1.77), with high certainty. PDR was 45.4 % (41.1 % - 49.8 %) with AI versus 30.6 % (26.5 % - 34.6 %) without AI; RR 1.48 (1.37 - 1.60), with high certainty. There was no difference in detection of advanced adenomas (mean advanced adenomas per colonoscopy 0.03 for each group, high certainty). Mean adenomas detected per colonoscopy was higher for small adenomas (≤ 5 mm) for AI versus non-AI (mean difference 0.15 0.12 - 0.18), but not for larger adenomas (> 5 - ≤ 10 mm, mean difference 0.03 0.01 - 0.05; > 10 mm, mean difference 0.01 0.00 - 0.02; high certainty). Data on cancer are unavailable.
AI-based polyp detection systems during colonoscopy increase detection of small nonadvanced adenomas and polyps, but not of advanced adenomas.
Background
Colorectal cancer is the third most frequent cancer in the world. As the sojourn time for this cancer is several years and a good prognosis is associated with early stage diagnosis, ...screening has been implemented in a number of countries. Both screening with faecal occult blood test and flexible sigmoidoscopy have been shown to reduce mortality from colorectal cancer in randomised controlled trials. The comparative effectiveness of these tests on colorectal cancer mortality has, however, never been evaluated, and controversies exist over which test to choose.
Objectives
To compare the effectiveness of screening for colorectal cancer with flexible sigmoidoscopy to faecal occult blood testing.
Search methods
We searched MEDLINE and EMBASE (November 16, 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (2012, Issue 11) and reference lists for eligible studies.
Selection criteria
Randomised controlled trials comparing screening with flexible sigmoidoscopy or faecal occult blood testing to each other or to no screening. Only studies reporting mortality from colorectal cancer were included. Faecal occult blood testing had to be repeated (annually or biennially).
Data collection and analysis
Data retrieval and assessment of risk of bias were performed independently by two review authors. Standard meta‐analyses using a random‐effects model were conducted for flexible sigmoidoscopy and faecal occult blood testing (FOBT) separately and we calculated relative risks with 95% confidence intervals (CI). We used a Bayesian approach (a contrast‐based network meta‐analysis method) for indirect analyses and presented the results as posterior median relative risk with 95% credibility intervals. We assessed the quality of evidence using GRADE.
Main results
We identified nine studies comprising 338,467 individuals randomised to screening and 405,919 individuals to the control groups. Five studies compared flexible sigmoidoscopy to no screening and four studies compared repetitive guaiac‐based FOBT (annually and biennially) to no screening. We did not consider that study risk of bias reduced our confidence in our results. We did not identify any studies comparing the two screening methods directly. When compared with no screening, colorectal cancer mortality was lower with flexible sigmoidoscopy (relative risk 0.72; 95% CI 0.65 to 0.79, high quality evidence) and FOBT (relative risk 0.86; 95% CI 0.80 to 0.92, high quality evidence). In the analyses based on indirect comparison of the two screening methods, the relative risk of dying from colorectal cancer was 0.85 (95% credibility interval 0.72 to 1.01, low quality evidence) for flexible sigmoidoscopy screening compared to FOBT. No complications occurred after the FOBT test itself, but 0.03% of participants suffered a major complication after follow‐up. Among more than 60,000 flexible sigmoidoscopy screening procedures and almost 6000 work‐up colonoscopies, a major complication was recorded in 0.08% of participants. Adverse event data should be interpreted with caution as the reporting of adverse effects was incomplete.
Authors' conclusions
There is high quality evidence that both flexible sigmoidoscopy and faecal occult blood testing reduce colorectal cancer mortality when applied as screening tools. There is low quality indirect evidence that screening with either approach reduces colorectal cancer deaths more than the other. Major complications associated with screening require validation from studies with more complete reporting of harms.
Clostridium difficile
is the leading cause of nosocomial infectious diarrhea. New treatment strategies are needed. In this letter, preliminary data on fecal therapy as primary treatment are assessed.
The long-term effects of sigmoidoscopy screening on colorectal cancer (CRC) incidence and mortality in women and men are unclear.
To determine the effectiveness of flexible sigmoidoscopy screening ...after 15 years of follow-up in women and men.
Randomized controlled trial. (ClinicalTrials.gov: NCT00119912).
Oslo and Telemark County, Norway.
Adults aged 50 to 64 years at baseline without prior CRC.
Screening (between 1999 and 2001) with flexible sigmoidoscopy with and without additional fecal blood testing versus no screening. Participants with positive screening results were offered colonoscopy.
Age-adjusted CRC incidence and mortality stratified by sex.
Of 98 678 persons, 20 552 were randomly assigned to screening and 78 126 to no screening. Adherence rates were 64.7% in women and 61.4% in men. Median follow-up was 14.8 years. The absolute risks for CRC in women were 1.86% in the screening group and 2.05% in the control group (risk difference, -0.19 percentage point 95% CI, -0.49 to 0.11 percentage point; HR, 0.92 CI, 0.79 to 1.07). In men, the corresponding risks were 1.72% and 2.50%, respectively (risk difference, -0.78 percentage point CI, -1.08 to -0.48 percentage points; hazard ratio HR, 0.66 CI, 0.57 to 0.78) (P for heterogeneity = 0.004). The absolute risks for death from CRC in women were 0.60% in the screening group and 0.59% in the control group (risk difference, 0.01 percentage point CI, -0.16 to 0.18 percentage point; HR, 1.01 CI, 0.77 to 1.33). The corresponding risks for death from CRC in men were 0.49% and 0.81%, respectively (risk difference, -0.33 percentage point CI, -0.49 to -0.16 percentage point; HR, 0.63 CI, 0.47 to 0.83) (P for heterogeneity = 0.014).
Follow-up through national registries.
Offering sigmoidoscopy screening in Norway reduced CRC incidence and mortality in men but had little or no effect in women.
Norwegian government and Norwegian Cancer Society.
In this randomized trial involving 84,585 participants in Poland, Norway, and Sweden, the risk of colorectal cancer at 10 years was lower among those invited to undergo screening colonoscopy than ...among those assigned to no screening.
IMPORTANCE: Colorectal cancer is a major health burden. Screening is recommended in many countries. OBJECTIVE: To estimate the effectiveness of flexible sigmoidoscopy screening on colorectal cancer ...incidence and mortality in a population-based trial. DESIGN, SETTING, AND PARTICIPANTS: Randomized clinical trial of 100 210 individuals aged 50 to 64 years, identified from the population of Oslo city and Telemark County, Norway. Screening was performed in 1999-2000 (55-64–year age group) and in 2001 (50-54–year age group), with follow-up ending December 31, 2011. Of those selected, 1415 were excluded due to prior colorectal cancer, emigration, or death, and 3 could not be traced in the population registry. INTERVENTIONS: Participants randomized to the screening group were invited to undergo screening. Within the screening group, participants were randomized 1:1 to receive once-only flexible sigmoidoscopy or combination of once-only flexible sigmoidoscopy and fecal occult blood testing (FOBT). Participants with positive screening test results (cancer, adenoma, polyp ≥10 mm, or positive FOBT) were offered colonoscopy. The control group received no intervention. MAIN OUTCOMES AND MEASURES: Colorectal cancer incidence and mortality. RESULTS: A total of 98 792 participants were included in the intention-to-screen analyses, of whom 78 220 comprised the control group and 20 572 comprised the screening group (10 283 randomized to receive a flexible sigmoidoscopy and 10 289 to receive flexible sigmoidoscopy and FOBT). Adherence with screening was 63%. After a median of 10.9 years, 71 participants died of colorectal cancer in the screening group vs 330 in the control group (31.4 vs 43.1 deaths per 100 000 person-years; absolute rate difference, 11.7 95% CI, 3.0-20.4; hazard ratio HR, 0.73 95% CI, 0.56-0.94). Colorectal cancer was diagnosed in 253 participants in the screening group vs 1086 in the control group (112.6 vs 141.0 cases per 100 000 person-years; absolute rate difference, 28.4 95% CI, 12.1-44.7; HR, 0.80 95% CI, 0.70-0.92). Colorectal cancer incidence was reduced in both the 50- to 54-year age group (HR, 0.68; 95% CI, 0.49-0.94) and the 55- to 64-year age group (HR, 0.83; 95% CI, 0.71-0.96). There was no difference between the flexible sigmoidoscopy only vs the flexible sigmoidoscopy and FOBT screening groups. CONCLUSIONS AND RELEVANCE: In Norway, once-only flexible sigmoidoscopy screening or flexible sigmoidoscopy and FOBT reduced colorectal cancer incidence and mortality on a population level compared with no screening. Screening was effective both in the 50- to 54-year and the 55- to 64-year age groups. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00119912
Management of non-curative endoscopic resection of T1 colon cancer Bernklev, Linn; Nilsen, Jens Aksel; Augestad, Knut Magne ...
Baillière's best practice & research. Clinical gastroenterology,
February 2024, 2024-Feb, 2024-02-00, 20240201, Letnik:
68
Journal Article
Recenzirano
Odprti dostop
Endoscopic resection techniques enable en-bloc resection of T1 colon cancers. A complete removal of T1 colon cancer can be considered curative when histologic examination of the specimens shows none ...of the high-risk factors for lymph nodes metastases. Criteria predicting lymph nodes metastases include deep submucosal invasion, poor differentiation, lymphovascular invasion, and high-grade tumor budding. In these cases, complete (R0), local endoscopic resection is considered sufficient as negligible risk of lymph nodes metastases does not outweigh morbidity and mortality associated with surgical resection. Challenges arise when endoscopic resection is incomplete (RX/R1) or high-risk histological features are present. The risk of lymph node metastasis in T1 CRC ranges from 1% to 36.4%, depending on histologic risk factors. Presence of any risk factor labels the patient “high risk,” warranting oncologic surgery with mesocolic lymphadenectomy. However, even if 70%–80% of T1-CRC patients are classified as high-risk, more than 90% are without lymph node involvement after oncological surgery. Surgical overtreatment in T1 CRC is a challenge, requiring a balance between oncologic safety and minimizing morbidity/mortality. This narrative review explores the landscape of managing non-curative T1 colon cancer, focusing on the choice between advanced endoscopic resection techniques and surgical interventions. We discuss surveillance strategies and shared decision-making, emphasizing the importance of a multidisciplinary approach.
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