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Gastroenterology Jan 2020The incidence of colorectal cancer (CRC) is increasing worldwide. CRC has high mortality when detected at advanced stages, yet it is also highly preventable. Given the... (Review)
Review
The incidence of colorectal cancer (CRC) is increasing worldwide. CRC has high mortality when detected at advanced stages, yet it is also highly preventable. Given the difficulties in implementing major lifestyle changes or widespread primary prevention strategies to decrease CRC risk, screening is the most powerful public health tool to reduce mortality. Screening methods are effective but have limitations. Furthermore, many screen-eligible people remain unscreened. We discuss established and emerging screening methods, and potential strategies to address current limitations in CRC screening. A quantum step in CRC prevention might come with the development of new screening strategies, but great gains can be made by deploying the available CRC screening modalities in ways that optimize outcomes while making judicious use of resources.
Topics: Colonoscopy; Colorectal Neoplasms; Early Detection of Cancer; Global Burden of Disease; Health Plan Implementation; Healthy Lifestyle; Humans; Incidence; Mass Screening; Occult Blood; Patient Acceptance of Health Care; Practice Guidelines as Topic; Risk Assessment; Sigmoidoscopy
PubMed: 31394083
DOI: 10.1053/j.gastro.2019.06.043 -
BMJ Open Oct 2019Evaluate effectiveness, harms and burdens of faecal blood testing, sigmoidoscopy and colonoscopy screening for colorectal cancer over 15 years. (Meta-Analysis)
Meta-Analysis
OBJECTIVE
Evaluate effectiveness, harms and burdens of faecal blood testing, sigmoidoscopy and colonoscopy screening for colorectal cancer over 15 years.
DESIGN
We performed an update of a Cochrane systematic review, and performed network meta-analysis comparing randomised trials evaluating colorectal cancer screening with guaiac faecal occult blood test (gFOBT) (annual, biennial), faecal immunochemical test (FIT) (annual, biennial), sigmoidoscopy (once-only) or colonoscopy (once-only) in a healthy population, aged 50-79 years. We conducted subgroup analysis on sex. Follow-up >5 years was required for analysis of colorectal cancer incidence and mortality.
RESULTS
12 randomised trials proved eligible. Compared with no-screening, we found high certainty evidence for sigmoidoscopy screening slightly reducing colorectal cancer incidence (relative risk (RR) 0.76; 95% confidence interval (CI 0.70 to 0.83) and mortality (RR 0.74; 95% CI 0.69 to 0.80), while gFOBT screening had little or no difference on colorectal cancer incidence, but slightly reduced colorectal cancer mortality (annual: RR 0.69; 95% CI 0.56 to 0.86, biennial: RR 0.88; 95% CI 0.82 to 0.93). No screening test reduced mortality nor incidence by more than six per 1000 screened over 15 years. Sigmoidoscopy had a greater effect in men, for both colorectal cancer incidence (women: RR 0.86; 95% CI 0.81 to 0.92, men: RR 0.75, 95% CI 0.71 to 0.79), and mortality (women: RR 0.85; 95% CI 0.71 to 0.96, men: RR 0.67; 95% CI 0.61 to 0.75) (moderate certainty).
CONCLUSIONS
In a 15-year perspective, sigmoidoscopy reduces colorectal cancer incidence, while sigmoidoscopy, annual and biennial gFOBT all reduce colorectal cancer mortality. Sigmoidoscopy may reduce colorectal cancer incidence and mortality more in men than in women.
PROSPERO REGISTRATION NUMBER
CRD42018093401.
Topics: Adenoma; Aged; Carcinoma; Colonoscopy; Colorectal Neoplasms; Early Detection of Cancer; Humans; Middle Aged; Occult Blood; Sigmoidoscopy
PubMed: 31578199
DOI: 10.1136/bmjopen-2019-032773 -
Gastroenterology Mar 2021The comparative effectiveness of sigmoidoscopy and fecal immunochemical testing (FIT) for colorectal cancer (CRC) screening is unknown. (Comparative Study)
Comparative Study Randomized Controlled Trial
BACKGROUND & AIMS
The comparative effectiveness of sigmoidoscopy and fecal immunochemical testing (FIT) for colorectal cancer (CRC) screening is unknown.
METHODS
Individuals aged 50-74 years living in Southeast Norway were randomly invited between 2012 and 2019 to either once-only flexible sigmoidoscopy or FIT screening every second year. Colonoscopy was recommended after sigmoidoscopy if any polyp of ≥10 mm, ≥3 adenomas, any advanced adenomas, or CRC was found or, subsequent to, FIT >15 μg hemoglobin/g feces. Data for this report were obtained after complete recruitment in both groups and included 2 full FIT rounds and part of the third round. Outcome measures were participation, neoplasia detection, and adverse events. Age-standardized detection rates and age-adjusted odds ratios (ORs) were calculated.
RESULTS
We included 139,291 individuals: 69,195 randomized to sigmoidoscopy and 70,096 to FIT. The participation rate was 52% for sigmoidoscopy, 58% in the first FIT round, and 68% for 3 cumulative FIT rounds. Compared to sigmoidoscopy, the detection rate for CRC was similar in the first FIT round (0.25% vs 0.27%; OR, 0.92; 95% confidence interval [CI], 0.75-1.13) but higher after 3 FIT rounds (0.49% vs 0.27%; OR, 1.87; 95% CI, 1.54-2.27). Advanced adenoma detection rate was lower in the first FIT round compared to sigmoidoscopy at 1.4% vs 2.4% (OR, 0.57; 95% CI, 0.53-0.62) but higher after 3 cumulative FIT rounds at 2.7% vs 2.4% (OR, 1.14; 95% CI, 1.05-1.23). There were 33 (0.05%) serious adverse events in the sigmoidoscopy group compared to 47 (0.07%) in the FIT group (P = .13).
CONCLUSIONS
Participation was higher and more CRC and advanced adenomas were detected with repeated FIT compared to sigmoidoscopy. The risk of perforation and bleeding was comparable. Clinicaltrials.gov, Number: NCT01538550.
Topics: Aged; Colonoscopy; Colorectal Neoplasms; Early Detection of Cancer; Female; Humans; Male; Mass Screening; Middle Aged; Norway; Occult Blood; Odds Ratio; Pilot Projects; Sigmoidoscopy
PubMed: 33227280
DOI: 10.1053/j.gastro.2020.11.037 -
Gastroenterology Mar 2020Endoscopic screening reduces incidence and mortality of colorectal cancer (CRC) because precursor lesions, such as conventional adenomas or serrated polyps, are removed....
BACKGROUND & AIMS
Endoscopic screening reduces incidence and mortality of colorectal cancer (CRC) because precursor lesions, such as conventional adenomas or serrated polyps, are removed. Individuals with polypectomies are advised to undergo colonoscopy surveillance to prevent CRC. However, guidelines for surveillance intervals after diagnosis of a precursor lesion, particularly for individuals with serrated polyps, vary widely, and lack sufficient supporting evidence. Consequently, some high-risk patients do not receive enough surveillance and lower-risk subjects receive excessive surveillance.
METHODS
We examined the association between findings from first endoscopy and CRC risk among 122,899 participants who underwent flexible sigmoidoscopy or colonoscopy in the Nurses' Health Study 1 (1990-2012), Nurses' Health Study 2 (1989-2013), or the Health Professionals Follow-up Study (1990-2012). Endoscopic findings were categorized as no polyp, conventional adenoma, or serrated polyp (hyperplastic polyp, traditional serrated adenoma, or sessile serrated adenoma, with or without cytological dysplasia). Conventional adenomas were classified as advanced (≥10 mm, high-grade dysplasia, or tubulovillous or villous histology) or nonadvanced, and serrated polyps were assigned to categories of large (≥10 mm) or small (<10 mm). We used a Cox proportional hazards regression model to calculate the hazard ratios (HRs) of CRC incidence, after adjusting for various potential risk factors.
RESULTS
After a median follow-up period of 10 years, we documented 491 incident cases of CRC: 51 occurred in 6161 participants with conventional adenomas, 24 in 5918 participants with serrated polyps, and 427 in 112,107 participants with no polyp. Compared with participants with no polyp detected during initial endoscopy, the multivariable HR for incident CRC in individuals with an advanced adenoma was 4.07 (95% confidence interval [CI] 2.89-5.72) and the HR for CRC in individuals with a large serrated polyp was 3.35 (95% CI 1.37-8.15). In contrast, there was no significant increase in risk of CRC in patients with nonadvanced adenomas (HR 1.21; 95% CI 0.68-2.16, P = .52) or small serrated polyps (HR 1.25; 95% CI 0.76-2.08; P = .38).
CONCLUSIONS
These findings provide support for guidelines that recommend repeat lower endoscopy within 3 years of a diagnosis of advanced adenoma and large serrated polyps. In contrast, patients with nonadvanced adenoma or small serrated polyps may not require more intensive surveillance than patients without polyps.
Topics: Adenoma; Aged; Aged, 80 and over; Colonic Polyps; Colorectal Neoplasms; Female; Follow-Up Studies; Humans; Incidence; Male; Mass Screening; Middle Aged; Neoplasm Seeding; Practice Guidelines as Topic; Precancerous Conditions; Prospective Studies; Retrospective Studies; Risk Assessment; Risk Factors; Sigmoidoscopy; Time Factors
PubMed: 31302144
DOI: 10.1053/j.gastro.2019.06.039 -
Journal of Internal Medicine Aug 2011Colorectal cancer (CRC) is the third most common cause of cancer death worldwide and a major health problem. In this review, the different approaches for CRC screening... (Review)
Review
Colorectal cancer (CRC) is the third most common cause of cancer death worldwide and a major health problem. In this review, the different approaches for CRC screening will be outlined with emphasis on evidence-based medicine. Evidence from randomized trials on the effectiveness of CRC screening is summarized. Several screening tools for CRC are available. They can be categorized according to their mode of action: early detection tools such as the faecal occult blood test (FOBT) and cancer prevention tools such as flexible sigmoidoscopy and colonoscopy. Meta-analyses of randomized trials show that FOBT screening reduces CRC mortality by 16% (risk ratio 0.84; 95% confidence interval (CI) 0.78-0.9) compared with 30% (risk ratio 0.7; 95% CI 0.6-0.81) for flexible sigmoidoscopy screening. FOBT screening is cheap and noninvasive, but results in large numbers of false-positive tests and needs to be repeated frequently. Flexible sigmoidoscopy is more invasive, but is effective for once-only screening. Although colonoscopy screening is used in some countries, no randomized trials have been conducted to estimate its benefit, and therefore, it should not be recommended at the present time. Faecal occult blood test and flexible sigmoidoscopy are the two CRC screening tools that can be recommended as they have been proven to reduce CRC mortality. Colonoscopy has the potential to be superior to FOBT and flexible sigmoidoscopy, but needs to be evaluated in randomized trials before any recommendation can be provided.
Topics: Colonoscopy; Colorectal Neoplasms; Early Diagnosis; Evidence-Based Medicine; Humans; Mass Screening; Occult Blood; Sigmoidoscopy
PubMed: 21575082
DOI: 10.1111/j.1365-2796.2011.02399.x -
American Family Physician Apr 2001Flexible sigmoidoscopy remains a common tool used for the periodic screening of colorectal cancer. Most organizations recommend screening at three- to five-year... (Review)
Review
Flexible sigmoidoscopy remains a common tool used for the periodic screening of colorectal cancer. Most organizations recommend screening at three- to five-year intervals beginning at age 50 for persons with average risk. Extensive training in endoscopic maneuvering, colorectal anatomy and pathologic recognition is required. Most physicians report comfort performing the procedure unsupervised after 10 to 25 precepted sessions. The procedure involves the insertion of the sigmoidoscope through the anus and distal rectum and advancement of the scope tip to an average depth of 48 to 55 cm in the sigmoid colon. Once the sigmoidoscope has been appropriately advanced, the scope is slowly withdrawn, allowing for the inspection of colon mucosa during withdrawal. Polyps less than 5 mm in diameter should be biopsied. Polyps 5 to 10 mm or greater can be assumed to be adenomatous, and follow-up colonoscopy for complete polypectomy is required. Diverticulosis, hemorrhoids, nonspecific colitis and pseudomembranes may also be encountered during inspection. Use of preprocedural benzodiazepines can be helpful in reducing patient discomfort. 2001;63:1375-80,1383-4,1385-8.)
Topics: Age Factors; Biopsy; Colonic Polyps; Colorectal Neoplasms; Family Practice; Humans; Intestinal Diseases; Intraoperative Complications; Preoperative Care; Sigmoidoscopy
PubMed: 11310651
DOI: No ID Found -
Gastrointestinal Endoscopy Clinics of... Oct 2019Colonoscopic polypectomy is fundamental to effective prevention of colorectal cancer. Polypectomy reduces colorectal cancer incidence and mortality by altering the... (Review)
Review
Colonoscopic polypectomy is fundamental to effective prevention of colorectal cancer. Polypectomy reduces colorectal cancer incidence and mortality by altering the natural history and progression of precancerous precursor polyps. Epidemiologic data from the United States, where colorectal cancer rates have been steadily declining in parallel with screening efforts, provide indisputable evidence about the effectiveness of polypectomy. Randomized controlled trials of fecal occult blood tests and flexible sigmoidoscopy, and observational colonoscopy studies, provide additional support. Longitudinal studies have shown variable levels of protection after polypectomy, highlighting the central importance of high quality and adequate surveillance of higher-risk patients.
Topics: Aged; Colonic Polyps; Colonoscopy; Colorectal Neoplasms; Evidence-Based Medicine; Female; Humans; Longitudinal Studies; Male; Middle Aged; Precancerous Conditions; Primary Prevention; Prognosis; Randomized Controlled Trials as Topic; Risk Assessment; SEER Program; Sigmoidoscopy; Treatment Outcome; United States
PubMed: 31445683
DOI: 10.1016/j.giec.2019.05.001 -
Canadian Medical Association Journal Mar 1974Sigmoidoscopy is the most important gastrointestinal procedure and is essential for the correct interpretation of lower bowel symptoms. The indications are many and...
Sigmoidoscopy is the most important gastrointestinal procedure and is essential for the correct interpretation of lower bowel symptoms. The indications are many and there are no contraindications. If done with care it is safe and inexpensive and within the capability of all practising physicians.Consideration for the patient's comfort and dignity, correct positioning, and advancement of the instrument only under direct vision should ensure a satisfactory examination.
Topics: Adult; Age Factors; Aged; Anus Diseases; Diet; Enema; Family Practice; Female; Fiber Optic Technology; Gastrointestinal Diseases; Humans; Male; Middle Aged; Palpation; Physician-Patient Relations; Posture; Rectal Diseases; Sigmoidoscopes; Sigmoidoscopy
PubMed: 4817215
DOI: No ID Found -
Hong Kong Medical Journal = Xianggang... Feb 2016Colorectal cancer is one of the top three cancers in the world in terms of incidence. Colonoscopy, which many regard as the gold standard in diagnosis of colonic polyps... (Review)
Review
Colorectal cancer is one of the top three cancers in the world in terms of incidence. Colonoscopy, which many regard as the gold standard in diagnosis of colonic polyps and neoplasm, is costly, invasive and labour-intensive, and deemed an unsuitable population-wide index screening tool. Alternative modalities, including guaiac and immunohistochemical faecal occult blood tests, computed tomographic colonography, colon capsule endoscopy, flexible sigmoidoscopy, and double-contrast barium enema are available. The procedures, test characteristics, and their implications are reviewed. Immunohistochemical faecal occult blood testing appears to be the most suitable population-wide screening test for an average-risk population, with flexible sigmoidoscopy as an alternative. More evidence is needed to determine the role of computed tomographic colonography and colon capsule endoscopy in colorectal cancer screening.
Topics: Colonography, Computed Tomographic; Colonoscopy; Colorectal Neoplasms; Early Detection of Cancer; Humans; Immunohistochemistry; Occult Blood; Sigmoidoscopy
PubMed: 26744124
DOI: 10.12809/hkmj154685 -
Zeitschrift Fur Gastroenterologie Dec 1972
Topics: Colonic Diseases; Endoscopy; Humans; Intestinal Polyps; Proctoscopy; Sigmoidoscopy
PubMed: 4657271
DOI: No ID Found