BACKGROUND: Use of the faecal immunochemical test (FIT) to triage patients with iron deficiency (ID) for colonoscopy due to suspected colorectal cancer (CRC) may improve distribution of colonoscopic resources. We reviewed the diagnostic performance of FIT for detecting advanced colorectal neoplasia, including CRC and advanced pre-cancerous neoplasia (APCN), in patients with ID, with or without anaemia.
METHODS: We performed a systematic review of three databases for studies comprising of patients with ID, with or without anaemia, completing a quantitative FIT within six months prior to colonoscopy, where test performance was compared against the reference standard colonoscopy. Random effects meta-analyses determined the diagnostic performance of FIT for advanced colorectal neoplasia.
RESULTS: Nine studies were included on a total of n=1761 patients with ID, reporting FIT positivity thresholds between 4-150 µg haemoglobin/g faeces. Only one study included a non-anaemic ID (NAID) cohort. FIT detected CRC and APCN in ID patients with 90.7 % and 49.3 % sensitivity, and 81.0 % and 82.4 % specificity, respectively. FIT was 88.0 % sensitive and 83.4 % specific for CRC in patients with ID anaemia at a FIT positivity threshold of 10 µg haemoglobin/g faeces.
CONCLUSIONS: FIT shows high sensitivity for advanced colorectal neoplasia and may be used to triage those with ID anaemia where colonoscopic resources are limited, enabling those at higher risk of CRC to be prioritised for colonoscopy. There is a need for further research investigating the diagnostic performance of FIT in NAID patients.

There are significant inequities in colorectal cancer (CRC) screening and outcomes. Via literature review, we assessed CRC screening rates for the vulnerable populations served by free clinics.
A systematic review was conducted for publications on CRC screening in free clinics. Outcomes included CRC screening characteristics, population demographics, and limitations. A methodological quality assessment was completed.
Out of 63 references, six studies were included, representing 8,844 participants. Black or Hispanic participants were the plurality in all but one study. All participants were uninsured. Median CRC screening rate was 48.4% (range 6.6-78.9%). Screening methods included colonoscopy, fecal occult blood test, flexible sigmoidoscopy, and fecal immunochemical test. Clinics offering only one screening method had a mean screening rate of 7.2% while those with multiple methods had a screening rate of 65.4%.
Access to multiple CRC screening modalities correlates with higher screening rates in free clinics. More work is needed to increase CRC screening in free clinics.

UNASSIGNED: Adenoma detection rate (ADR) is higher after a positive fecal immunochemical test (FIT) compared to direct screening colonoscopy.
UNASSIGNED: This meta-analysis evaluated how ADR, the rates of advanced adenoma detection (AADR), colorectal cancer detection (CDR), and sessile serrated lesion detection (SSLDR) are affected by different FIT positivity thresholds.
UNASSIGNED: We searched MEDLINE, EMBASE, CINAHL, and EBM Reviews databases for studies reporting ADR, AADR, CDR, and SSLDR according to different FIT cut-off values in asymptomatic average-risk individuals aged 50-74 years old. Data were stratified according to sex, age, time to colonoscopy, publication year, continent, and FIT kit type. Study quality, heterogeneity, and publication bias were assessed.
UNASSIGNED: Overall, 4280 articles were retrieved and fifty-eight studies were included (277,661 FIT-positive colonoscopies; mean cecal intubation 96.3%; mean age 60.8 years; male 52.1%). Mean ADR was 56.1% (95% CI 53.4 - 58.7%), while mean AADR, CDR, and SSLDR were 27.2% (95% CI 24.4 - 30.1%), 5.3% (95% CI 4.7 - 6.0%), and 3.0% (95% CI 1.7 - 4.6%), respectively. For each 20 μg Hb/g increase in FIT cut-off level, ADR increased by 1.54% (95% CI 0.52 - 2.56%, p < 0.01), AADR by 3.90% (95% CI 2.76 - 5.05%, p < 0.01) and CDR by 1.46% (95% CI 0.66 - 2.24%, p < 0.01). Many detection rates were greater amongst males and Europeans.
UNASSIGNED: ADRs in FIT-positive colonoscopies are influenced by the adopted FIT positivity threshold, and identified targets, importantly, proved to be higher than most current societal recommendations.

The faecal immunochemical test (FIT) is an inexpensive and convenient modality to screen for colorectal cancer. However, its one-time sensitivity for detecting colorectal cancer and cancer precursors is limited. There is growing interest in using the non-haemoglobin contents of FIT residual buffer to enhance colonic neoplasia detection.
To establish from the literature a framework to catalogue candidate biomarkers within FIT residual buffer for non-invasive colorectal cancer screening.
The search strategy evaluated PubMed, Scopus, Web of Science, Embase, and Google Scholar for publications through 25 October 2023, with search terms including FIT, buffer, OC-sensor, biomarkers, microbiome, microRNA (miR), colon, rectum, screening, neoplasm, and early detection. Studies employing home-based collection samples using quantitative FIT first processed for haemoglobin were included. One author reviewed all articles; a second author completed a 20% full-text audit to ensure adherence to eligibility criteria.
A broad search yielded 1669 studies and application of eligibility criteria identified 18 relevant studies. Multiple protein, DNA/RNA, and microbiome biomarkers (notably haptoglobin, miR-16, miR-27a-3p, miR-92a, miR-148a-3p, miR-223, miR-421, let-7b-5p, and Tyzzerella 4) were associated with colorectal neoplasia. Furthermore, studies highlighted the short-term stability of biomarkers for clinical use and long-term stability for research purposes.
This scoping review summarises the framework and progress of research on stability of biomarkers in FIT residual buffer and their associations with colorectal neoplasia to guide opportunities for further confirmatory studies to enhance colorectal cancer screening.

BACKGROUND: To assess the long-term association between organised colorectal cancer (CRC) screening strategies and CRC-relate mortality.
METHODS: We systematically reviewed studies on organised CRC screening through PubMed, Ovid Medline, Embase and Cochrane from the inception. We retrieved characteristics of organised CRC screening from included literature and matched mortality (over 50 years) of those areas from the International Agency for Research on Cancer in May 2023. The variations of mortality were reported via the age-standardised mortality ratio. A random-effects model was used to synthesis results.
RESULTS: We summarised 58 organised CRC screening programmes and recorded > 2.7 million CRC-related deaths from 22 countries where rollout screening programmes were performed. The CRC screening strategy with faecal tests (guaiac faecal occult blood test (gFOBT) or faecal immunochemical tests (FIT)) or colonoscopy as the primary screening offer was associated with a 41.8% reduction in mortality, which was higher than those offered gFOBT (4.4%), FIT (16.7%), gFOBT or FIT (16.2%), and faecal tests (gFOBT or FIT) or flexible sigmoidoscopy (16.7%) as primary screening test. The longer duration of screening was associated with a higher reduction in the pooled age-standardised mortality ratio. In particular, the pooled age-standardised mortality ratio became non-significant when the screening of FIT was implemented for less than 5 years.
CONCLUSIONS: A CRC screening programme running for > 5 years was associated with a reduction of CRC-related mortality. Countries with a heavy burden of CRC should implement sustainable, organised screening providing a choice between faecal tests and colonoscopy as a preferred primary test.

OBJECTIVE: This study systematically reviewed and meta-analyzed the performance of the Asia-Pacific Colorectal Screening (APCS) score and its incorporation with the fecal immunochemical test (FIT) in stratifying the risk of advanced colorectal neoplasia (ACN).
METHODS: We systematically searched for relevant articles in 12 electronic databases and registers on October 20, 2021, and updated the search to September 1, 2023. Random-effect models were used to obtain the pooled performance statistics of the APCS score for ACN risk.
RESULTS: From the 101 records screened, 13 eligible studies in the Asia-Pacific region involving 69 762 subjects who had undergone colonoscopy were enrolled. The pooled prevalences of ACN in the average-risk (AR) tier (APCS 0-1), moderate-risk (MR) tier (APCS 2-3), and high-risk (HR) tier (APCS ≥ 4) groups were 0.9%, 3.1%, and 8.1%, respectively. Compared with the combined AR-MR group, the HR group was significantly associated with a higher ACN risk (pooled diagnostic odds ratio: 2.84, 95% confidence interval [CI]: 2.35-3.45, P < 0.001). The APCS score showed a sensitivity of 0.42 (95% CI: 0.40-0.44) and a specificity of 0.86 (95% CI: 0.85-0.86) for predicting the ACN risk, with a weighted area under the curve of 0.642 (95% CI: 0.610-0.657). The combination of the APCS score and FIT substantially improved ACN risk identification, demonstrating pooled diagnostic odds ratios of 4.02 (95% CI: 2.50-6.49) in the AR-MR groups and 5.44 (95% CI: 1.89-15.63) in the MR-HR groups.
CONCLUSIONS: The APCS score could effectively stratify the ACN risk in the Asia-Pacific population. Incorporating FIT further improves its performance in identifying high-risk subjects who should be prioritized for colonoscopy screenings.

OBJECTIVE: This review aims to summarize the different colorectal cancer guidelines for average-risk and high-risk individuals from various countries.
METHODS: A comprehensive literature search regarding guidelines, consensus recommendations, or position statements about colorectal cancer screening published within the last 10 years (1st January 2012 to 27th August 2022), was performed at EBSCOhost, JSTOR, PubMed, ProQuest, SAGE, and ScienceDirect.
RESULTS: A total of 18 guidelines were included in this review. Most guidelines recommended screening between 45 and 75 years for average-risk individuals. Recommendations regarding colorectal cancer screening in high-risk individuals were more varied and depended on the risk factor. For high-risk individuals with a positive family history of colorectal cancer or advanced colorectal polyp, screening should begin at age 40. Some frequently suggested screening modalities in order of frequency are colonoscopy, FIT, and CTC. Furthermore, several screening intervals were suggested, including colonoscopy every 10 years for average-risk and every 5-10 years for high-risk individuals, FIT annually in average-risk and every 1-2 years in high-risk individuals, and CTC every five years for all individuals.
CONCLUSIONS: All individuals with average-risk should undergo colorectal cancer screening between 45 and 75. Meanwhile, individuals with higher risks, such as those with a positive family history, should begin screening at age 40. Several recommended screening modalities were suggested, including colonoscopy every 10 years in average-risk and every 5-10 years in high-risk, FIT annually in average-risk and every 1-2 years in high-risk, and CTC every five years.

暂无摘要。

Physical harm from Colorectal Cancer Screening tends to be inadequately measured and reported in clinical trials. Also, studies of ongoing Colorectal Cancer Screening programs have found more frequent and severe physical harm from screening procedures, e.g., bleeding and perforation, than reported in previous trials. Therefore, the objectives of the study were to systematically review the evidence on the risk of bleeding and perforation in Colorectal Cancer Screening.
Systematic review with descriptive statistics and random-effects meta-analyses.
We systematically searched five databases for studies investigating physical harms related to Colorectal Cancer Screening. We assessed the internal and the external validity using the ROBINS-I tool and the GRADE approach. Harm estimates was calculated using mixed Poisson regression models in random-effect meta-analyses.
We included 89 studies. Reporting and measurement of harms was inadequate in most studies. In effect, the risk of bias was critical in 97.3% and serious in 98.3% of studies. All GRADE ratings were very low. Based on severe findings with not-critical risk of bias and 30 days follow-up, the risk of bleedings per 100,000 people screened were 8 [2;24] for sigmoidoscopy, 229 [129;408] for colonoscopy following fecal immunochemical test, 68 [39;118] for once-only colonoscopy, and 698 [443;1045] for colonoscopy following any screening tests. The risk of perforations was 88 [56;138] for colonoscopy following fecal immunochemical test and 53 [25;112] for once-only colonoscopy. There were no findings within the subcategory severe perforation with long-term follow-up for colonoscopy following any screening tests and sigmoidoscopy.
Harm estimates varied widely across studies, reporting and measurement of harms was mostly inadequate, and the risk of bias and GRADE ratings were very poor, collectively leading to underestimation of harm. In effect, we consider our estimates of perforation and bleeding as conservative, highlighting the need for better reporting and measurement in future studies.
PROSPERO registration number: CRD42017058844.

BACKGROUND: Screening adherence is important in reducing colorectal cancer (CRC) incidence and mortality. Disparity in CRC screening adherence was observed in populations of different socioeconomic status (SES), but the direction and strength of the association remained unclear.
OBJECTIVE: We aimed to systematically review all the observational studies that have analyzed the association between SES and adherence to organized CRC screening based on fecal occult blood tests.
METHODS: We systematically reviewed the studies in PubMed, Embase, and Web of Science and reference lists of relevant reviews from the inception of the database up until June 7, 2023. Individual SES, neighborhood SES, and small-area SES were included, while any SES aggregated by geographic areas larger than neighbors were excluded. Studies assessing SES with any index or score combining indicators of income, education, deprivation, poverty, occupation, employment, marital status, cohabitation, and others were included. A random effect model meta-analysis was carried out for pooled odds ratios (ORs) and relative risks for adherence related to SES.
RESULTS: Overall, 10 studies, with a total of 3,542,379 participants and an overall adherence rate of 64.9%, were included. Compared with low SES, high SES was associated with higher adherence (unadjusted OR 1.73, 95% CI 1.42-2.10; adjusted OR 1.53, 95% CI 1.28-1.82). In the subgroup of nonindividual-level SES, the adjusted association was significant (OR 1.57, 95% CI 1.26-1.95). However, the adjusted association was insignificant in the subgroup of individual-level SES (OR 1.46, 95% CI 0.98-2.17). As for subgroups of the year of print, not only was the unadjusted association significantly stronger in the subgroup of early studies (OR 1.97, 95% CI 1.59-2.44) than in the subgroup of late studies (OR 1.43, 95% CI 1.31-1.56), but also the adjusted one was significantly stronger in the early group (OR 1.86, 95% CI 1.43-2.42) than in the late group (OR 1.26, 95% CI 1.14-1.39), which was consistent and robust. Despite being statistically insignificant, the strength of the association seemed lower in studies that did not adjust for race and ethnicity (OR 1.31, 95% CI 1.21-1.43) than the overall estimate (OR 1.53, 95% CI 1.28-1.82).
CONCLUSIONS: The higher-SES population had higher adherence to fecal occult blood test-based organized CRC screening. Neighborhood SES, or small-area SES, was more competent than individual SES to be used to assess the association between SES and adherence. The disparity in adherence between the high SES and the low SES narrowed along with the development of interventions and the improvement of organized programs. Race and ethnicity were probably important confounding factors for the association.