Once-only colonoscopy or two rounds of faecal immunochemical testing 2 years apart for colorectal cancer screening (SCREESCO): preliminary report of a randomised controlled trial

Risk of Colorectal Cancer Associated With Frequency of Colorectal Polyp Diagnosis in Relatives

BACKGROUND & AIMS

The aim of the study was to evaluate the association of frequency of polyp diagnosis in relatives with the risk of overall and early-onset colorectal cancer (CRC).

METHODS

Data from nationwide Swedish family cancer datasets (1964-2018) were leveraged to calculate standardized incidence ratios for individuals with a family history of polyp by frequency of polyp diagnosis in family members.

RESULTS

A total of 11,676,043 individuals were followed for up to 54 years. Compared with the risk in individuals without a family history of colorectal tumor (n = 142,234), the risk of overall CRC was 1.4-fold in those with 1 first-degree relative (FDR) with 1-time polyp diagnosis (95% CI, 1.3-1.4; n = 11,035; early-onset standardized incidence ratio [SIR], 1.4; 95% CI, 1.3-1.5; n = 742). The risk was significantly higher in individuals with 1 FDR with 2 or more (frequent) polyp diagnoses (overall CRC: SIR, 1.8; 95% CI, 1.8-1.9; early-onset CRC: SIR, 2.3; 95% CI, 2.0-2.6). A rather similar risk was observed for individuals with ≥2 FDRs with 1-time polyp diagnosis (overall CRC: SIR, 1.9; 95% CI, 1.7-2.1; early-onset CRC: SIR, 2.2; 95% CI, 1.5-2.9). Individuals with ≥2 FDRs with frequent polyp diagnoses had a 2.4-fold overall risk (95% CI, 2.2-2.7) and a 3.9-fold early-onset risk (95% CI, 2.8-5.3). Younger age at polyp diagnosis in FDRs was associated with an increased risk of CRC. A family history of polyp in second-degree relatives was important only when there were frequent diagnoses of polyp.

CONCLUSIONS

A higher frequency of colorectal polyp diagnosis in relatives is associated with a greater risk of CRC, especially early-onset CRC. This risk is independent of number of affected relatives or youngest age at polyp diagnosis. These findings underscore the need for more personalized CRC screening strategies that are tailored to individuals with a family history of polyp.

Effect of invitation to colonoscopy versus faecal immunochemical test screening on colorectal cancer mortality (COLONPREV): a pragmatic, randomised, controlled, non-inferiority trial

BACKGROUND

Colonoscopy and the faecal immunochemical test are accepted strategies for colorectal cancer screening in the average-risk population (ie, people aged ≥50 years without personal or family history of colorectal cancer). In this trial, we aimed to compare whether invitation to screening with faecal immunochemical test was non-inferior to colonoscopy in a screening programme.

METHODS

COLONPREV was a pragmatic, randomised, controlled, non-inferiority trial done at 15 tertiary hospitals across eight regions of Spain. Eligible participants were presumptively healthy and aged between 50 years and 69 years without a personal history of colorectal cancer, adenoma or inflammatory bowel disease, family history of hereditary or familial colorectal cancer (ie, two or more first-degree relatives with colorectal cancer or one diagnosed before age 60 years), severe comorbidities, or previous colectomy. Participants were randomly assigned (1:1) to one-time colonoscopy or biennial faecal immunochemical test before invitation to screening. The primary endpoint was colorectal cancer mortality at 10 years, assessed in the intention-to-screen population. An absolute difference of less than 0·16 percentage points was required to show non-inferiority. This trial was registered with ClinicalTrials.gov, NCT00906997.

FINDINGS

Between June 1, 2009, and Dec 31, 2021, 57 404 individuals were randomly assigned to receive an invitation for colonoscopy (n=28 708) or the faecal immunochemical test (n=28 696). The intention-to-screen population consisted of 26 332 individuals in the colonoscopy group and 26 719 in the faecal immunochemical test group. In the intention-to-screen population, participation in any form of screening was 31·8% in the colonoscopy group and 39·9% in the faecal immunochemical test group (risk ratio [RR] 0·79 [95% CI 0·77 to 0·82]). Faecal immunochemical testing was non-inferior to colonoscopy with regard to the risk of colorectal cancer mortality at 10 years: the risk was 0·22% (55 deaths) in the colonoscopy group and 0·24% (60 deaths) in the faecal immunochemical test group (risk difference -0·02 [95% CI -0·10 to 0·06; RR 0·92 [95% CI 0·64 to 1·32]; pnon-inferiority=0·0005).

INTERPRETATION

Participation in screening was higher among individuals invited to faecal immunochemical test screening than colonoscopy screening. On the basis of participation observed in this study, a faecal immunochemical test-based programme was non-inferior to a colonoscopy-based programme for colorectal cancer-related mortality.

FUNDING

Fundación Científica de la Asociación Española contra el Cáncer and Instituto de Salud Carlos III.

Colonoscopy-Related Adverse Events in the 21st Century: An Updated Systematic Review and Meta-Analysis

INTRODUCTION

Colonoscopy is one of the most commonly performed endoscopic procedures and is generally considered low-risk. However, when adverse events (AEs) occur, they can present significant challenges in clinical practice. The aim of this study was to estimate the global incidence of colonoscopy-related AEs.

METHODS

We searched multiple databases for population-based studies reporting the incidence of colonoscopy-related AEs up to December 22, 2024. Meta-analyses were conducted for both gastrointestinal and nongastrointestinal AEs. Subgroup analyses were performed based on factors including World Health Organization region, publication year, sample size, data collection method, and study design.

RESULTS

Among the 30,818 records identified, 82 population-based studies from 24 countries were included, involving a total of 38.5 million colonoscopies. The estimated incidence per 10,000 colonoscopies was as follows: gastrointestinal AEs, including perforation (5.15; 95% confidence interval [CI] 4.19-6.34, I2 = 99%), bleeding (18.39; 95% CI 13.53-24.99, I2 = 100%), and splenic injury (0.61; 95% CI 0.43-0.85, I2 = 93%); nongastrointestinal AEs, including cardiovascular events (52.11; 95% CI 18.67-144.59, I2 = 100%), respiratory events (4.26; 95% CI 0.73-24.99, I2 = 100%), and deaths related to colonoscopy (0.18; 95% CI 0.10-0.34, I2 = 74%). Subgroup analyses yielded partially divergent findings. The majority of the included studies exhibited a low to moderate risk of bias.

DISCUSSION

This comprehensive meta-analysis provides valuable insights into the global incidence of colonoscopy-related AEs and underscores the imperative need for continuous efforts to enhance the safety of this procedure.

Colorectal cancer incidence following a negative colonoscopy in fecal immunochemical test-based screening: a nationwide cohort study after 8 years of screening in Denmark

Screening participants with a positive fecal immunochemical test (FIT) result and a subsequent negative colonoscopy are quarantined from the Danish bowel cancer screening program for 8 years. This recommendation is based on evidence from settings other than FIT-based screening, but referral of this evidence is not necessarily sufficient. We estimated the colorectal cancer (CRC) risk among these FIT-positive/colonoscopy-negative individuals and compared it with the risk in a historical unscreened population.Using national health registers in Denmark, we compared 29 936 participants with a positive FIT but negative colonoscopy with 720 850 randomly selected unscreened controls born 9 years earlier (ratio 1:24). Controls were assigned a pseudo-colonoscopy date 9 years prior to the negative colonoscopy group. We examined cases per 10 000 person-years and estimated relative risks (RR) and 95%CIs for CRC.After 8 years' follow-up, CRC risk was lower among FIT-positive/colonoscopy-negative participants compared with controls (RR 0.72, 95%CI 0.61-0.84). By age group and sex, the lower risk was only evident for women and men in their 60s (RR 0.67 [95%CI 0.47-0.96] and RR 0.65 [95%CI 0.48-0.88], respectively) and men in their 70s (RR 0.60 [95%CI 0.44-0.84]).The overall risk for CRC was lower for individuals with a positive FIT but negative colonoscopy compared with unscreened controls. However, the lower risk might not justify 8 years of quarantine, especially for women and younger age groups. Individualized screening is warranted and transfer of evidence from non-FIT screening should be done carefully.

Legal-involved veterans are less likely to receive guideline-concordant colorectal cancer screening

BACKGROUND

Programs to improve health care for adults with criminal legal involvement, including those who have been released from incarceration in jails or prisons or who are under court or community supervison, understandably focus on treatment for mental illness, drug overdose, and suicide. However, criminal legal-involved adults also have higher risk of developing and dying from medical conditions, such as cancer, relative to the general population. Colorectal cancer (CRC) screening among legal-involved adults, particularly those who have been incarcerated, might be delayed or missed.

METHODS

We conducted an observational study of national Veterans Health Administration (VHA) electronic health record data to compare the CRC screening rate between legal-involved Veterans, identified through their contact with the Veterans Justice Programs, and non-legal-involved Veterans. We included patients ages 46 to 75 eligible for average-risk screening in fiscal year 2022. Our main outcome of guideline-concordant CRC screening included stool-based testing, CT colonography, flexible sigmoidoscopy, and colonoscopy. Comparisons were estimated using an unadjusted multilevel logistic regression model with a random intercept for facility. Secondary analyses included examining associations between patient-level factors and screening receipt using adjusted models as well as assessing the variation in screening rates across 129 VHA facilities.

RESULTS

There were 27,597 legal-involved and 3,467,396 non-legal-involved patients who met screening eligibility. Only 47% of legal-involved patients were up to date with screening, compared to 54% of non-legal-involved patients (OR = 0.77 [95% CI: 0.75 to 0.79]; risk difference = -6.5% [95% CI: -7.1% to -5.9%]). Adjusted odds of screening were higher for patients with an assigned primary care provider (OR = 2.49 [95% CI: 2.48 to 2.51]). Screening rates varied widely across facilities, ranging from 24 to 75% for legal-involved patients and from 30 to 68% for non-legal-involved patients. Legal-involved patients had significantly lower screening rates at 49 facilities and a higher rate at two facilities, compared to non-legal-involved patients.

CONCLUSIONS

Nearly half of VHA patients were behind on recommended CRC screening, and legal-involved VHA patients had even lower rates. Current VHA efforts to improve legal-involved patients' connection to primary care providers may result in improved screening rates.

Single-round performance of colorectal cancer screening programs: a network meta-analysis of randomized clinical trials

BACKGROUND

Demonstrating mortality reduction in new colorectal cancer (CRC) screening programs through randomized clinical trials (RCTs) is challenging. We systematically reviewed single-round program performance outcomes using a stepwise approach proposed by the World Endoscopy Organization CRC Screening Committee framework.

METHODS

The MEDLINE, EMBASE, Central, and Ichushi Web databases were searched until October 28, 2024, to find RCTs comparing guaiac-based and immunochemical fecal occult blood testing (gFOBT and FIT), flexible sigmoidoscopy (FS), computed tomographic colonography (CTC), and total colonoscopy (TCS). Paired reviewers screened studies, extracted data, and assessed bias risk. A Bayesian random-effects network meta-analysis was conducted, and the certainty of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach. The primary outcome was advanced neoplasia (AN) detection, and the secondary outcomes were participation and colorectal cancer (CRC) detection, all during the first screening round.

RESULTS

Eighteen RCTs (437,072 invitees) were included. The risk of bias was low or raised some concerns for screening participation, but it was high for detection outcomes. In the network meta-analysis of 15 RCTs not allowing crossover, the FIT-based program had a higher AN detection rate than the gFOBT-based program (relative risk [RR] 2.48; 95% credible interval [CrI] 1.52-4.21; moderate certainty). AN detection rates were not different in the CTC- (RR 1.01; CrI 0.43-2.23; very low certainty) and TCS-based (RR 1.03; CrI 0.54-1.78; low certainty) programs compared with the FS-based program. All the visualization modality programs had higher AN detection rates than the FIT-based program (FS: RR 2.13 [CrI 1.38-3.77]; CTC 2.16 [1.11-4.51]; and TCS 2.19 [1.43-3.48]; all with low certainty). Low event rates precluded definitive conclusions regarding CRC detection (very low to low certainty). The TCS-based program had the worst participation rate (very low to low certainty). Comparative data allowing crossover were limited.

CONCLUSIONS

This is the first network meta-analysis that evaluates program-level initial performance indicators. FIT-based programs likely detect more AN cases than gFOBT-based programs, while FS-, CTC-, and TCS-based programs may outperform FIT. Due to limitations in first-round results, long-term outcomes should be assessed after 10-15 years.

Endoscopist adenoma detection rate associated with neoplasia detection during subsequent-round colonoscopy in fecal immunochemical test-based colorectal cancer screening: cross-sectional analysis of the SCREESCO randomized controlled trial

BACKGROUND AND AIMS

In colorectal cancer screening with the fecal immunochemical test (FIT), the optimal follow-up after first-round colonoscopy for a positive FIT, particularly after negative colonoscopy, is unknown. Therefore, using Screening of Swedish Colons (SCREESCO) study data, we aimed to elucidate the risk factors for the detection of colorectal neoplasia in second-round colonoscopy, which can affect recommendations for the optimal follow-up.

METHODS

We performed a cross-sectional analysis using data from SCREESCO participants undergoing colonoscopy after a positive 2-stool FIT, with a positivity cutoff value of ≥10 μg/g feces, in both the first and second rounds separated by a 2-year interval. We assessed the associations between colorectal neoplasia detection in second-round colonoscopy and participant characteristics, FIT concentrations, first-round colonoscopy results, and endoscopists' adenoma detection rates (ADRs), which were categorized as very low, low, intermediate, and high.

RESULTS

This study included 343 individuals. Despite negative first-round colonoscopies (n = 230), colorectal cancer and advanced colorectal neoplasia (ACN) were detected in 0.9% and 8.3% of participants in the second-round colonoscopy, respectively. An association was demonstrated between the first-round endoscopists' ADRs and the risk of second-round ACN detection. The multivariable odds ratios of the first-round intermediate and high ADRs, compared with the very low ADR, for second-round ACN detection were 0.17 (95% confidence interval [CI], 0.02-0.79) and 0.19 (95% CI, 0.04-0.86), respectively.

CONCLUSIONS

The impact of endoscopists' ADRs on ACN detection in subsequent-round colonoscopies underscores the importance of considering ADR for optimal follow-up after first-round colonoscopy in an FIT-based screening program.

Integrating plasma proteome with genome reveals novel protein biomarkers in colorectal cancer

BACKGROUND

Biomarkers for colorectal cancer (CRC) can complement population screening methods, but so far, few plasma proteins have been identified as biomarkers for CRC. This study aims to identify potential protein biomarkers and therapeutic targets for CRC within the proteome range.

METHODS

We extracted summary-level data of circulating protein from 7 published genome-wide association studies (GWASs) of plasma proteome for Mendelian randomization (MR), summary-data-based MR (SMR), and co-localization analyses to screen and validate proteins with causal effects in CRC. In addition, we further conducted druggability evaluation, prognosis analysis at the transcriptional level, and enrichment expression at the single-cell level, highlighting the important role of these plasma protein biomarkers in CRC.

RESULTS

We identified 117 plasma protein biomarkers associated with CRC risk, with 9 proteins showing stronger genetic correlations in Bayesian co-localization (PP.H4 > 0.70). Further, we found 26 protein-coding genes already used in targeted drug development and may potentially become therapeutic targets for CRC. In prognosis analysis, the encoding genes of plasma proteins exhibited consistent effects with MR analysis and can serve as prognostic biomarkers for CRC. Additionally, we also found that the differentially expressed proteins are mainly expressed in fibroblasts, endothelial cells, macrophages, and T cells.

CONCLUSION

Our study has identified plasma protein biomarkers associated with CRC risk, which may complement population screening methods for CRC and achieve more precise treatment for patients.

Secretome and Proteome of Extracellular Vesicles Provide Protein Markers of Lung and Colorectal Cancer

Colorectal cancer (CRC) and lung cancer (LC) are leading causes of cancer-related mortality, highlighting the need for minimally invasive diagnostic, prognostic, and predictive markers for these cancers. Proteins secreted by a tumor into the extracellular space directly, known as the tumor secretome, as well as proteins in the extra-cellular vesicles (EVs), represent an attractive source of biomarkers for CRC and LC. We performed proteomic analyses on secretome and EV samples from LC (A549, NCI-H23, NCI-H460) and CRC (Caco2, HCT116, HT-29) cell lines and targeted mass spectrometry on EVs from plasma samples of 20 patients with CRC and 19 healthy controls. A total of 782 proteins were identified across the CRC and LC secretome and EV samples. Of these, 22 and 44 protein markers were significantly elevated in the CRC and LC samples, respectively. Functional annotation revealed enrichment in proteins linked to metastasis and tumor progression for both cancer types. In EVs isolated from the plasma of patients with CRC, ITGB3, HSPA8, TUBA4A, and TLN1 were reduced, whereas FN1, SERPINA1, and CST3 were elevated, compared to healthy controls. These findings support the development of minimally invasive liquid biopsy methods for the detection, prognosis, and treatment monitoring of LC and CRC.

Adherence, risk perception, and attitudes towards colorectal cancer screening: A road to individualized screening?

BACKGROUND & AIMS

Colorectal cancer (CRC) ranks second globally in cancer-related deaths and there is ongoing debate on the best populational screening strategy. This study aimed to evaluate individuals' intention to adhere to CRC screening, screening method preference, and barriers to screening.

METHODS

Cross-sectional study conducted in northern Portugal, where a populational fecal occult blood test (FOBT) program is implemented. The validated PERCEPT-PREVENT tool was administered across 3 groups: a) not yet invited to screening b) accepted FOBT screening, and c) primary colonoscopy screening.

RESULTS

A total of 397 participants completed the PERCEPT-PREVENT questionnaire and were compared by screening status. Intention to adhere was reported at a high rate (95 %;n = 354) and was positively influenced by knowledge of the screening rationale (OR8.96, 95 %CI 3.61-22.25). Most were unaware of symptoms (64 %;n = 253), risk factors (68 %;n = 271), and associated screening procedure risks (58 %;n = 230). Lower barrier scores for FOBT (7 ± 3) compared to colonoscopy (10 ± 3) were observed for screening naïve respondents (p < 0.001). Previous FOBT screening led to a lower preference for colonoscopy (previous FOBT screening 56 % vs not yet invited to screening 75 % vs previous primary colonoscopy 90 %; p < 0.001).

DISCUSSION

A greater understanding of the screening rationale enhances adherence. FOBT was highly accepted among never-screened participants. Colonoscopy should be offered to FOBT decliners, as personalized screening approaches could improve participation rates.

Colonoscopy Remains an Important Option for Primary Screening for Colorectal Cancer

Colonoscopy remains the most commonly used colorectal cancer screening test in the United States. A substantial portion of the screening population value the high sensitivity of colonoscopy for precancerous colorectal lesions of all sizes, which allows it to be performed at 10 year intervals in average-risk persons with negative examinations. Emerging evidence supports the eventual endorsement of 15 year intervals for patients with normal examinations. Considerable evidence supports an impact of colonoscopy on colorectal cancer incidence and mortality, including a randomized controlled trial of colonoscopy vs. no screening, numerous case-control and cohort studies, an impact of fecal blood testing on cancer incidence, and the impact of one randomized controlled trial of flexible sigmoidoscopy on proximal colon cancer incidence. Colonoscopy is the gold standard for detection of colorectal precancerous lesions, and continues to evolve with regard to sensitivity for precancerous lesions and the effectiveness and safety of precancerous lesion resection. Gains in detection of precancerous lesions have followed from a robust movement to improve colonoscopy quality, and development of non-device techniques such as patient rotation during withdrawal, water exchange colonoscopy, and double examination of one or more colonic segments. Further, development of devices to improve mucosal exposure during withdrawal (e.g. Endocuff Vision, distal cap attachment, and Computer-Aided Quality), and devices that highlight flat lesions (e.g. chromoendoscopy, electronic chromoendoscopy, and Computer-Aided Detection) have created opportunities to achieve very high levels of detection and thereby increase the protective benefits of colonoscopy. Further, colonoscopy resection safety has improved via the widespread use of cold resection for lesions < 10 mm in size, as well as sessile serrated lesions of all sizes. Colonoscopy can be offered to patients as one of multiple options for screening, or as the test of choice for patients with the highest pre-screening probability of cancer and precancerous lesions, or as the first test offered followed by offers of other screening tests if colonoscopy is declined (sequential offers of screening). Sequential offers of screening result in overall adherence to screening similar to offering multiple options, but with a higher fraction of patients undergoing colonoscopy. Given the long-lasting protective effects of colonoscopy and its improving effectiveness and safety, colonoscopy remains a useful option for primary average-risk colorectal cancer screening.

Does Colonoscopy as a First Screening Test Still Make Sense?-Counterpoint

Colonoscopy has been widely regarded as the gold standard for its high diagnostic accuracy and preventive potential. However, its invasive nature, high cost, and suboptimal participation rates limit its utility at the population level. Non-invasive screening tests, notably the fecal immunochemical test (FIT) and multitarget stool DNA tests, present promising alternatives that may improve screening participation and reduce barriers to participation. Among these, FIT has demonstrated a consistent advantage in enhancing participation, which subsequently contributes to better long-term outcomes in CRC prevention. FIT-based two-step screening offers several practical advantages, including cost-effectiveness, non-invasiveness, and greater flexibility. Moreover, the quantitative nature of FIT allows for adjustable sensitivity thresholds and the ability of risk stratification, making it adaptable across diverse populations and scenarios. Through serial testing, FIT can increase cumulative detection rates over time. This approach facilitates the identification of high-risk individuals, allowing for more judicious use of colonoscopy resources and reducing unnecessary invasive procedures, especially among low-risk populations. Notably, evidence indicates that participation to FIT-based screening is consistently higher than to colonoscopy, which enhances the detection of early-stage cancers and advanced adenomas in the long run. Given the constraints of limited endoscopic capacity, the aging population, and the recent lowering of the recommended screening age due to the rising incidence of early-onset CRC, FIT emerges as a practical, flexible solution. The role of two-step FIT screening in improving participation and enabling risk-stratified, personalized approaches to CRC prevention is pivotal, advocating for its expanded integration into future screening paradigms.

Impact of colorectal cancer screening by primary tumor location in a real-world setting in Japan

The objective of this retrospective observational study was to investigate the impact of fecal occult blood test (FOBT) as colorectal cancer (CRC) screening by primary tumor location. We compared the risk of requiring treatment for advanced disease and total medical costs per patient between CRC patients who underwent FOBT within 1 year before initial treatment for CRC and those who did not, using the JMDC Claims database, large-scale health insurance claims and checkup data in Japan. Treatment for advanced disease was defined as (1) nonendoscopic therapy or (2) chemotherapy or radiotherapy, performed during the follow-up period. A total of 1194 participants with CRC (right-sided, 22.2%; left-sided, 60.4%) who initiated treatment between 2010 and 2016 and underwent health checkups within 1 year before the initial treatment were enrolled and followed up for an average of 46.1 months. A significantly lowered risk ratio (RR) of chemotherapy or radiotherapy and total medical costs were observed in FOBT group for left-sided CRC [RR = 0.78 (95% confidence interval, 0.63-0.97), mean and median costs = 4.1 vs. 5.6 and 2.4 vs. 2.9 million JPY; P = 0.018], while they were not observed for right-sided CRC [RR = 0.88 (95% confidence interval, 0.61-1.28), mean and median costs = 4.0 vs. 4.1 and 2.7 vs. 2.9 million JPY; P = 0.995]. This study demonstrated the improved outcomes by FOBT for left-sided CRC, whereas its impact was limited for right-sided CRC.

Stool and blood biomarkers for colorectal cancer management: an update on screening and disease monitoring

BACKGROUND

Biomarkers have revolutionized the management of colorectal cancer (CRC), facilitating early detection, prevention, personalized treatment, and minimal residual disease (MRD) monitoring. This review explores current CRC screening strategies and emerging biomarker applications.

MAIN BODY

We summarize the landscape of non-invasive CRC screening and MRD detection strategies, discuss the limitations of the current approaches, and highlight the promising potential of novel biomarker solutions. The fecal immunochemical test remained the cornerstone of CRC screening, but its sensitivity has been improved by assays that combined its performance with other stool analytes. However, their sensitivity for advanced adenomas and the patient compliance both remain suboptimal. Blood-based tests promise to increase compliance but require further refinement to compete with stool-based biomarker tests. The ideal scenario involves leveraging blood tests to increase screening participation, and simultaneously promote stool- and endoscopy-based screening among those who are compliant. Once solely reliant on upfront surgery followed by stage and pathology-driven adjuvant chemotherapy, the treatment of stage II and III colon cancer has undergone a revolutionary transformation with the advent of MRD testing after surgery. A decade ago, the concept of using a post-surgical test instead of stage and pathology to determine the need for adjuvant chemotherapy was disruptive. Today, a blood test may be more informative of the need for chemotherapy than the stage at diagnosis.

CONCLUSION

Biomarker research is not just improving, but bringing a transformative change to CRC clinical management. Early detection is not just getting better, but improving thanks to a multi-modality approach, and personalized treatment plans are not just becoming a reality, but a promising future with MRD testing.

Screening Colonoscopy to Reduce the Incidence and Mortality of Colorectal Cancer

BACKGROUND

Colorectal cancer (CRC) is a major concern because of its increasing incidence and mortality worldwide. Therefore, effective screening strategies are necessary to reduce its incidence.

SUMMARY

In addition to fecal immunochemical tests and computed tomography colonography, screening colonoscopy is expected to significantly contribute to the reduction of CRC. However, the timing of colonoscopy for CRC screening is not well-defined because of the lack of sufficient data. Additionally, the effectiveness of colonoscopy is affected by various factors known as quality indicators (QIs), such as the performance of the endoscopist; therefore, there are concerns regarding quality assurance. The adenoma detection rate (ADR) is a well-known QI of colonoscopy. Substantial evidence has suggested that improving the ADR could reduce the incidence and mortality of postcolonoscopy CRC.

KEY MESSAGES

Recent technological advancements have led to the development of image-enhanced endoscopy and the incorporation of artificial intelligence, and their ability to improve the ADR has been assessed. This review focused on screening colonoscopies and QIs and their ability to improve the ADR and incidence and mortality of CRC.

Colonoscopy findings after increasing two-stool faecal immunochemical test (FIT) cut-off: Cross-sectional analysis of the SCREESCO randomized trial

BACKGROUND

We determined the impact of an increased two-stool faecal immunochemical test (FIT) cut-off on colonoscopy positivity and relative sensitivity and specificity in the randomized controlled screening trial screening of Swedish colons conducted in Sweden.

METHODS

We performed a cross-sectional analysis of participants in the FIT arm that performed FIT between March 2014 and 2020 within the study registered with ClinicalTrials.gov, NCT02078804, who had a faecal haemoglobin concentration of at least 10 µg/g in at least one of two stool samples and who underwent a colonoscopy (n = 3841). For each increase in cut-off, we computed the positive predictive value (PPV), numbers needed to scope (NNS), sensitivity and specificity for finding colorectal cancer (CRC) and advanced neoplasia (AN; advanced adenoma or CRC) relative to cut-off 10 µg/g.

RESULTS

The PPV for AN increased from 23.0% (95% confidence intervals [CI]: 22.3%-23.6%) at cut-off 10 µg/g to 28.8% (95% CI: 27.8%-29.7%) and 33.1% (95% CI: 31.9%-34.4%) at cut-offs 20 and 40 µg/g, respectively, whereas the NNS to find a CRC correspondingly decreased from 41 to 27 and 19. The PPV for AN was higher in men than women at each cut-off, for example 31.5% (95% CI: 30.1%-32.8%) in men and 25.6% (95% CI: 24.3%-27.0%) in women at 20 µg/g. The relative sensitivity and relative specificity were similar in men and women at each cut-off.

CONCLUSION

A low cut-off of around 20-40 µg/g allows detection and removal of many AN compared to 10 µg/g while reducing the number of colonoscopies in both men and women.

Fecal Immunochemical Test Screening and Risk of Colorectal Cancer Death

Importance

The fecal immunochemical test (FIT) is widely used for colorectal cancer (CRC) screening, but evidence of its effectiveness is limited.

Objective

To evaluate whether FIT screening is associated with a lower risk of dying from CRC overall, according to cancer location, and within demographic groups.

Design, Setting, and Participants

This nested case-control study in a cohort of screening-eligible people was conducted in 2 large, integrated health systems of racially, ethnically, and socioeconomically diverse members with long-term programs of mailed FIT screening outreach. Eligible participants included people aged 52 to 85 years who died from colorectal adenocarcinoma between 2011 and 2017 (cases); cases were matched in a 1:8 ratio based on age, sex, health-plan membership duration, and geographic area to randomly selected persons who were alive and CRC-free on case's diagnosis date (controls). Data analysis was conducted from January 2002 to December 2017.

Exposures

Completing 1 or more FIT screenings in the 5-year period prior to the CRC diagnosis date among cases or the corresponding date among controls; in secondary analyses, 2- to 10-year intervals were evaluated.

Main Outcomes and Measures

The primary study outcome was CRC death overall and by tumor location. Secondary analyses were performed to assess CRC death by race and ethnicity.

Results

From a cohort of 2 127 128 people, a total of 10 711 participants (3529 aged 60-69 years [32.9%]; 5587 male [52.1%] and 5124 female [47.8%]; 1254 non-Hispanic Asian [11.7%]; 973 non-Hispanic Black [9.1%]; 1929 Hispanic or Latino [18.0%]; 6345 non-Hispanic White [59.2%]) was identified, including 1103 cases and 9608 controls. Among controls during the 10-year period prior to the reference date, 6101 (63.5%) completed 1 or more FITs with a cumulative 12.6% positivity rate (768 controls), of whom 610 (79.4%) had a colonoscopy within 1 year. During the 5-year period, 494 cases (44.8%) and 5345 controls (55.6%) completed 1 or more FITs. In regression analysis, completing 1 or more FIT screening was associated with a 33% lower risk of death from CRC (adjusted odds ratio [aOR], 0.67; 95% CI, 0.59-0.76) and 42% lower risk in the left colon and rectum (aOR, 0.58; 95% CI, 0.48-0.71). There was no association with right colon cancers (aOR, 0.83; 95% CI, 0.69-1.01) but the difference in the estimates between the right colon and left colon or rectum was statistically significant (P = .01). FIT screening was associated with lower CRC mortality risk among non-Hispanic Asian (aOR, 0.37; 95% CI, 0.23-0.59), non-Hispanic Black (aOR, 0.58; 95% CI, 0.39-0.85) and non-Hispanic White individuals (aOR, 0.70; 95% CI, 0.57-0.86) (P for homogeneity = .04 for homogeneity).

Conclusions and Relevance

In this nested case-control study, completing FIT was associated with a lower risk of overall death from CRC, particularly in the left colon, and the associations were observed across racial and ethnic groups. These findings support the use of FIT in population-based screening strategies.

Projected Colorectal Cancer Incidence and Mortality Based on Observed Adherence to Colonoscopy and Sequential Stool-Based Screening

INTRODUCTION

Modeling supporting recommendations for colonoscopy and stool-based colorectal cancer (CRC) screening tests assumes 100% sequential participant adherence. The impact of observed adherence on the long-term effectiveness of screening is unknown. We evaluated the effectiveness of a program of screening colonoscopy every 10 years vs annual high-sensitivity guaiac-based fecal occult blood testing (HSgFOBT) using observed sequential adherence data.

METHODS

The MIcrosimulation SCreening ANalysis (MISCAN) model used observed sequential screening adherence, HSgFOBT positivity, and diagnostic colonoscopy adherence in HSgFOBT-positive individuals from the National Colonoscopy Study (single-screening colonoscopy vs ≥4 HSgFOBT sequential rounds). We compared CRC incidence and mortality over 15 years with no screening or 10 yearly screening colonoscopy vs annual HSgFOBT with 100% and differential observed adherence from the trial.

RESULTS

Without screening, simulated incidence and mortality over 15 years were 20.9 (95% probability interval 15.8-26.9) and 6.9 (5.0-9.2) per 1,000 participants, respectively. In the case of 100% adherence, only screening colonoscopy was predicted to result in lower incidence; however, both tests lowered simulated mortality to a similar level (2.1 [1.6-2.9] for screening colonoscopy and 2.5 [1.8-3.4] for HSgFOBT). Observed adherence for screening colonoscopy (83.6%) was higher than observed sequential HSgFOBT adherence (73.1% first round; 49.1% by round 4), resulting in lower simulated incidence and mortality for screening colonoscopy (14.4 [10.8-18.5] and 2.9 [2.1-3.9], respectively) than HSgFOBT (20.8 [15.8-28.1] and 3.9 [2.9-5.4], respectively), despite a 91% adherence to diagnostic colonoscopy with FOBT positivity. The relative risk of CRC mortality for screening colonoscopy vs HSgFOBT was 0.75 (95% probability interval 0.68-0.80). Findings were similar in sensitivity analyses with alternative assumptions for repeat colonoscopy, test performance, risk, age, and projection horizon.

DISCUSSION

Where sequential adherence to stool-based screening is suboptimal and colonoscopy is accessible and acceptable-as observed in the national colonoscopy study, microsimulation, comparative effectiveness, screening recommendations.

Screening for liver fibrosis: lessons from colorectal and lung cancer screening

Many countries have incorporated population screening programmes for cancer, such as colorectal and lung cancer, into their health-care systems. Cirrhosis is more prevalent than colorectal cancer and has a comparable age-standardized mortality rate to lung cancer. Despite this fact, there are no screening programmes in place for early detection of liver fibrosis, the precursor of cirrhosis. In this Perspective, we use insights from colorectal and lung cancer screening to explore the benefits, challenges, implementation strategies and pathways for future liver fibrosis screening initiatives. Several non-invasive methods and referral pathways for early identification of liver fibrosis exist, but in addition to accurate detection, screening programmes must also be cost-effective and demonstrate benefit through a reduction in liver-related mortality. Randomized controlled trials are needed to confirm this. Future randomized screening trials should evaluate not only the screening tests, but also interventions used to halt disease progression in individuals identified through screening.

Colonoscopy vs the Fecal Immunochemical Test: Which is Best?

Although there is no debate around the effectiveness of colorectal cancer screening in reducing disease burden, there remains a question regarding the most effective and cost-effective screening modality. Current United States guidelines present a panel of options that include the 2 most commonly used modalities, colonoscopy and stool testing with the fecal immunochemical test (FIT). Large-scale comparative effectiveness trials comparing colonoscopy and FIT for colorectal cancer outcomes are underway, but results are not yet available. This review will separately state the "best case" for FIT and colonoscopy as the screening tool of first choice. In addition, the review will examine these modalities from a health economics perspective to provide the reader further context about the relative advantages of these commonly used tests.

Colorectal cancer screening with fecal immunochemical testing or primary colonoscopy: inequities in diagnostic yield

BACKGROUND

Socioeconomic inequalities in the uptake of colorectal cancer screening are well documented, but the implications on inequities in health gain remain unclear.

METHODS

Sixty-year-olds were randomly recruited from the Swedish population between March 2014 and March 2020 and invited to undergo either 2 rounds of fecal immunochemical testing (FIT) 2 years apart (n = 60 137) or primary colonoscopy just once (n = 30 400). By linkage to Statistics Sweden's registries, we obtained socioeconomic data. In each defined socioeconomic group, we estimated the cumulative yield of advanced neoplasia in each screening arm (intention-to-screen analysis). In the biennial FIT arm, we predicted the probability of exceeding the yield in the primary colonoscopy arm by linear extrapolation of the cumulative yield to (hypothetical) additional rounds of FIT.

RESULTS

In the lowest income group, the yield of advanced neoplasia was 1.63% (95% confidence interval [CI] = 1.35% to 1.93%) after 2 rounds of FIT vs 1.93% (95% CI = 1.49% to 2.40%) in the primary colonoscopy arm. Extrapolation to a third round of FIT implied a 86% probability of exceeding the yield in the primary colonoscopy arm. In the highest income group, we found a more pronounced yield gap between the 2 screening strategies-2.32% (95% CI = 2.15% to 2.49%) vs 3.71% (95% CI = 3.41% to 4.02%)- implying a low (2%) predicted probability of exceeding yield after a third round of FIT.

CONCLUSIONS

Yield of advanced neoplasia from 2 rounds of FIT 2 years apart was poorer as compared with primary colonoscopy, but the difference was less in lower socioeconomic groups.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT02078804.

Multiple-matrix metabolomics analysis for the distinct detection of colorectal cancer and adenoma

OBJECTIVES

Although colorectal cancer (CRC) is the leading cause of cancer-related morbidity and mortality, current diagnostic tests for early-stage CRC and colorectal adenoma (CRA) are suboptimal. Therefore, there is an urgent need to explore less invasive screening procedures for CRC and CRA diagnosis.

METHODS

Untargeted gas chromatography-mass spectrometry (GC-MS) metabolic profiling approach was applied to identify candidate metabolites. We performed metabolomics profiling on plasma samples from 412 subjects including 200 CRC patients, 160 CRA patients and 52 normal controls (NC). Among these patients, 45 CRC patients, 152 CRA patients and 50 normal controls had their fecal samples tested simultaneously.

RESULTS

Differential metabolites were screened in the adenoma-carcinoma sequence. Three diagnostic models were further developed to identify cancer group, cancer stage, and cancer microsatellite status using those significant metabolites. The three-metabolite-only classifiers used to distinguish the cancer group always keeps the area under the receiver operating characteristic curve (AUC) greater than 0.7. The AUC performance of the classifiers applied to discriminate CRC stage is generally greater than 0.8, and the classifiers used to distinguish microsatellite status of CRC is greater than 0.9.

CONCLUSION

This finding highlights potential early-driver metabolites in CRA and early-stage CRC. We also find potential metabolic markers for discriminating the microsatellite state of CRC. Our study and diagnostic model have potential applications for non-invasive CRC and CRA detection.

The role of endoscopist adenoma detection rate in in sex differences in colonoscopy findings: cross-sectional analysis of the SCREESCO randomized controlled trial

BACKGROUND

Fewer adenomas are detected at colonoscopy in women compared to men and failure to detect adenomas and sessile serrated polyps is associated with an increased risk of post-colonoscopy colorectal cancer. The aim of this study was to investigate whether this was in part due to the greater difficulty of conducting colonoscopy in women, with the difference being more apparent in colonoscopies conducted by less skilled endoscopists.

MATERIAL AND METHODS

Cross-sectional exploratory analysis of data on 16,551 individuals undergoing a primary colonoscopy (PCOL group) or colonoscopy after positive faecal immunochemical test (FIT group) within the randomized controlled trial SCREESCO. Endoscopist adenoma detection rate (ADR; low or high) was determined based on each endoscopist's colonoscopies performed in SCREESCO. In each study group, the relationship between the sex difference in colonoscopy outcome and endoscopist ADR was assessed using multiplicative interaction tests.

RESULTS

Endoscopists performed equally many colonoscopies in men and women (median 52% men). There were no signs of effect modification of the risk ratio of any finding (men vs women) by endoscopist ADR in the PCOL group (p = 0.33) or the FIT group (p = 0.30). The proportion of incomplete index colonoscopies was lower in men than in women in both groups and there was no effect modification by endoscopist ADR in either the PCOL group (p = 0.41) or the FIT group (p = 0.96).

CONCLUSIONS

This study provides no evidence that endoscopist skill measured by ADR underlies the sex difference in adenoma detection at colonoscopy. This study has trial number NCT02078804 and is registered with ClinicalTrials.gov.

Screening for Colorectal Cancer

Colorectal cancer (CRC) is the second leading cause of cancer death. Screening has been proven to reduce both cancer incidence and cancer-related mortality. Various screening tests are available, each with their own advantages and disadvantages and varying levels of evidence to support their use. Clinicians should offer CRC screening to average-risk persons aged 50 to 75 years; starting screening at age 45 years remains controversial. Screening may be beneficial in select persons aged 76 to 85 years, based on their overall health and screening history. Offering a choice of screening tests or sequentially offering an alternate test for those who do not complete screening can significantly increase participation.

A Cell-free DNA Blood-Based Test for Colorectal Cancer Screening

BACKGROUND

Colorectal cancer is the third most diagnosed cancer in adults in the United States. Early detection could prevent more than 90% of colorectal cancer-related deaths, yet more than one third of the screening-eligible population is not up to date with screening despite multiple available tests. A blood-based test has the potential to improve screening adherence, detect colorectal cancer earlier, and reduce colorectal cancer-related mortality.

METHODS

We assessed the performance characteristics of a cell-free DNA (cfDNA) blood-based test in a population eligible for colorectal cancer screening. The coprimary outcomes were sensitivity for colorectal cancer and specificity for advanced neoplasia (colorectal cancer or advanced precancerous lesions) relative to screening colonoscopy. The secondary outcome was sensitivity to detect advanced precancerous lesions.

RESULTS

The clinical validation cohort included 10,258 persons, 7861 of whom met eligibility criteria and were evaluable. A total of 83.1% of the participants with colorectal cancer detected by colonoscopy had a positive cfDNA test and 16.9% had a negative test, which indicates a sensitivity of the cfDNA test for detection of colorectal cancer of 83.1% (95% confidence interval [CI], 72.2 to 90.3). Sensitivity for stage I, II, or III colorectal cancer was 87.5% (95% CI, 75.3 to 94.1), and sensitivity for advanced precancerous lesions was 13.2% (95% CI, 11.3 to 15.3). A total of 89.6% of the participants without any advanced colorectal neoplasia (colorectal cancer or advanced precancerous lesions) identified on colonoscopy had a negative cfDNA blood-based test, whereas 10.4% had a positive cfDNA blood-based test, which indicates a specificity for any advanced neoplasia of 89.6% (95% CI, 88.8 to 90.3). Specificity for negative colonoscopy (no colorectal cancer, advanced precancerous lesions, or nonadvanced precancerous lesions) was 89.9% (95% CI, 89.0 to 90.7).

CONCLUSIONS

In an average-risk screening population, this cfDNA blood-based test had 83% sensitivity for colorectal cancer, 90% specificity for advanced neoplasia, and 13% sensitivity for advanced precancerous lesions. (Funded by Guardant Health; ECLIPSE ClinicalTrials.gov number, NCT04136002.).

The value of hypersensitivity quantitative fecal immunochemical test in early colorectal cancer detection

At present, both the incidence and mortality rates of colorectal cancer are on the rise, making early screening a crucial tool in reducing the fatality rate. Although colonoscopy is the recommended method according to the guidelines, compliance tends to be poor. The fecal immunochemical test (FIT), a new technology that uses latex immunoturbidimetry to detect fecal blood, offers high specificity and sensitivity. Additionally, it is low-cost, easy to operate, and less likely to be affected by food and drugs, thus improving the compliance rate for population screening. Compared to other screening techniques, FIT represents a safer and more accurate option. This article reviews the application of FIT in early colorectal cancer screening.

Impact of organised colorectal cancer screening on age-specific population incidences: evidence from a quasi-experimental study in Sweden

Colorectal cancer (CRC) incurs a significant disease burden globally. Organised CRC screening programmes have been widely implemented for early detection and prevention. To understand the public health impact of these programmes, quantitative evidence of changes in overall and age-specific population incidences is fundamental. We aimed to provide such evidence by exploiting a time lag in the implementation of organised screening in Sweden: two out of 21 regions (these two regions comprise nearly 20% of the total Swedish population) have offered organised screening since 2008; the other regions have offered CRC screening since 2021. Using registry data on diagnosed CRC cases and socio-demographics for all regions in Sweden over the period 1970-2019, Bayesian structural time series modelling and difference-in-differences were applied to analyse the impact of screening on age-specific population incidences over time (CRC cases per 100.000 persons/year). After inviting birth-year cohorts aged 60-69 years for stool-based testing, the incidence rate in the 70-74-year age group decreased significantly over time, with an average reduction of - 44·40 (95% CI - 58·15 to - 31·31) from 2011 to 2019 in the intervention regions. In the overall population aged 60-74 years, there was a net incidence decrease of - 7·99 (95% CI - 13·85 to - 2·39) since the initiation of organised screening in the intervention regions (2008-2019). Organised CRC screening for 60-69-year-olds generated a change in age-specific incidence patterns with a long-lasting incidence decrease in the 70-74-year-old population, implying reductions in the excess mortality and burden of the disease.

Association study for the role of MMP8 gene polymorphisms in Colorectal cancer susceptibility

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignant tumors, influenced by several genetic loci in its clinical phenotypes. The aim of this study was to determine the relationship between the MMP8 gene polymorphism and CRC risk in the Chinese Han population.

METHOD

This study recruited 688 CRC patients and 690 healthy controls. The relationship between MMP8 polymorphism and CRC susceptibility was assessed by calculating the odds ratio (OR) and 95% confidence interval (CI) after stratifying by age, gender, body mass index (BMI), smoking, and alcohol consumption under a multi-genetic model.

RESULTS

MMP8 rs3740938 was associated with increased CRC predisposition (p = 0.016, OR = 1.24, 95% CI: 1.04-1.48), and this association was detected particularly in subjects aged > 60 years, females, people with BMI > 24 kg/m2, smokers, and drinkers. Moreover, rs3740938 was found to be associated with the pathological type of rectal cancer.

CONCLUSIONS

Our results first displayed that rs3740938 in MMP8 was a risk factor for CRC predisposition. This finding may provide a new biological perspective for understanding the role of the MMP8 gene in CRC pathogenesis.

Examining the continuum of resistance model in two population-based screening studies in Sweden

In studies recruited on a voluntary basis, lack of representativity may impair the ability to generalize findings to the target population. Previous studies, primarily based on surveys, have suggested that generalizability may be improved by exploiting data on individuals who agreed to participate only after receiving one or several reminders, as such individuals may be more similar to non-participants than what early participants are. Assessing this idea in the context of screenings, we compared sociodemographic characteristics and health across early, late, and non-participants in two large population-based screening studies in Sweden: STROKESTOP II (screening for atrial fibrillation; 6,867 participants) and SCREESCO (screening for colorectal cancer; 39,363 participants). We also explored the opportunities to reproduce the distributions of characteristics in the full invited populations, either by assuming that the non-participants were similar to the late participants, or by applying a linear extrapolation model based on both early and late participants. Findings showed that early and late participants exhibited similar characteristics along most dimensions, including civil status, education, income, and health examination results. Both these types of participants in turn differed from the non-participants, with fewer married, lower educational attainments, and lower incomes. Compared to early participants, late participants were more likely to be born outside of Sweden and to have comorbidities, with non-participants similar or even more so. The two empirical models improved representativity in some cases, but not always. Overall, we found mixed support that data on late participation may be useful for improving representativeness of screening studies.

Randomized Trial of Facilitated Adherence to Screening Colonoscopy vs Sequential Fecal-Based Blood Test

BACKGROUND & AIMS

Colorectal cancer (CRC) screening guidelines include screening colonoscopy and sequential high-sensitivity fecal occult blood testing (HSgFOBT), with expectation of similar effectiveness based on the assumption of similar high adherence. However, adherence to screening colonoscopy compared with sequential HSgFOBT has not been reported. In this randomized clinical trial, we assessed adherence and pathology findings for a single screening colonoscopy vs sequential and nonsequential HSgFOBTs.

METHODS

Participants aged 40-69 years were enrolled at 3 centers representing different clinical settings. Participants were randomized into a single screening colonoscopy arm vs sequential HSgFOBT arm composed of 4-7 rounds. Initial adherence to screening colonoscopy and sequential adherence to HSgFOBT, follow-up colonoscopy for positive HSgFOBT tests, crossover to colonoscopy, and detection of advanced neoplasia or large serrated lesions (ADN-SERs) were measured.

RESULTS

There were 3523 participants included in the trial; 1761 and 1762 participants were randomized to the screening colonoscopy and HSgFOBT arms, respectively. Adherence was 1473 (83.6%) for the screening colonoscopy arm vs 1288 (73.1%) for the HSgFOBT arm after 1 round (relative risk [RR], 1.14; 95% CI, 1.10-1.19; P ≤ .001), but only 674 (38.3%) over 4 sequential HSgFOBT rounds (RR, 2.19; 95% CI, 2.05-2.33). Overall adherence to any screening increased to 1558 (88.5%) in the screening colonoscopy arm during the entire study period and 1493 (84.7%) in the HSgFOBT arm (RR, 1.04; 95% CI, 1.02-1.07). Four hundred thirty-six participants (24.7%) crossed over to screening colonoscopy during the first 4 rounds. ADN-SERs were detected in 121 of the 1473 participants (8.2%) in the colonoscopy arm who were adherent to protocol in the first 12 months of the study, whereas detection of ADN-SERs among those who were not sequentially adherent (n = 709) to HSgFOBT was subpar (0.6%) (RR, 14.72; 95% CI, 5.46-39.67) compared with those who were sequentially adherent (3.3%) (n = 647) (RR, 2.52; 95% CI, 1.61-3.98) to HSgFOBT in the first 4 rounds. When including colonoscopies from HSgFOBT patients who were never positive yet crossed over (n = 1483), 5.5% of ADN-SERs were detected (RR, 1.50; 95% CI, 1.15-1.96) in the first 4 rounds.

CONCLUSIONS

Observed adherence to sequential rounds of HSgFOBT was suboptimal compared with a single screening colonoscopy. Detection of ADN-SERs was inferior when nonsequential HSgFOBT adherence was compared with sequential adherence. However, the greatest number of ADN-SERs was detected among those who crossed over to colonoscopy and opted to receive a colonoscopy. The effectiveness of an HSgFOBT screening program may be enhanced if crossover to screening colonoscopy is permitted.

CLINICALTRIALS

gov, Number: NCT00102011.

Effect of flexible sigmoidoscopy-based screening on colorectal cancer incidence and mortality: an updated systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Our objective was to estimate the effect of flexible sigmoidoscopy (FS)-based screening on colorectal cancer (CRC) incidence and mortality by conducting an updated meta-analysis of randomized controlled trials (RCTs).

METHODS

PubMed, Web of Science, Embase, and Cochrane Library searched for RCTs from database inception to December 2022. The methodological quality of the RCTs was assessed using the Cochrane Collaboration Risk of Bias Tool. RevMan 5.4 was used for this meta-analysis.

RESULTS

Four RCTs involving 457, 871 patients were included. This meta-analysis revealed that FS-based screening was associated with a 20% relative risk reduction in CRC incidence [RR = 0.80; 95% CI (0.75, 0.86); P < 0.00001], and a 24% reduction in CRC mortality [RR = 0.76; 95% CI (0.70, 0.82); P < 0.00001]. In addition, this meta-analysis revealed that FS-based screening reduced the incidence[RR = 0.68; 95% CI (0.60, 0.77); P < 0.00001] and mortality[RR = 0.64; 95% CI (0.49, 0.83); P = 0.0007] of distal CRC, but had no significant effect on proximal colon cancer.

CONCLUSION

FS-based screening appeared to be effective in reducing distal CRC incidence and mortality in patients at average risk compared to no intervention, but had no significant effect on proximal colon cancer.

Increasing the accuracy of colorectal cancer screening

INTRODUCTION

Colorectal cancer (CRC) is a major health issue, being responsible for nearly 10% of all cancer-related deaths. Since CRC is often an asymptomatic or paucisymptomatic disease until it reaches advanced stages, screening is crucial for the diagnosis of preneoplastic lesions or early CRC.

AREAS COVERED

The aim of this review is to summarize the literature evidence on currently available CRC screening tools, with their pros and cons, focusing on the level of accuracy reached by each test over time. We also provide an overview of novel technologies and scientific advances that are currently being investigated and that in the future may represent real game-changers in the field of CRC screening.

EXPERT OPINION

We suggest that best screening modalities are annual or biennial FIT and colonoscopy every 10 years. We believe that the introduction of artificial intelligence (AI)-tools in the CRC screening field could lead to a significant improvement of the screening efficacy in reducing CRC incidence and mortality in the future. More resources should be put into implementing CRC programmes and support research project to further increase accuracy of CRC screening tests and strategies.

Serum metabolite signatures in normal individuals and patients with colorectal adenoma or colorectal cancer using UPLC-MS/MS method

Colorectal cancer (CRC) is one of the main causes of cancer-related deaths worldwide. Sporadic CRC develops from normal mucosa via adenoma to adenocarcinoma, which provides a long screening window for clinical detection. However, early diagnosis of sporadic colorectal adenoma (CRA) and CRC using serum metabolic screening remains unclear. The purpose of this study was to identify some promising signatures for distinguishing the different pathological metabolites of colorectal mucosal malignant transformation. A total of 238 endogenous metabolites were elected. We found that CRA and CRC patients had 72 and 73 different metabolites compared with healthy controls, respectively. There were 20 different metabolites between CRA and CRC patients. The potential metabolites of tumor growth (including patients with CRA and CRC) were found, such as A-d-glucose, D-mannose, N-acetyl-D-glucosamine, L-cystine, Sarcosine, TXB 2, 12-Hete, and chenodeoxycholic acid. Compared with CRA, 3,4,5-trimethoxybenzoic acid was significantly higher in CRC patients. There results prompt us to use the potential serum signatures to screen CRC as the novel strategy. Serum metabolite screening is useful for early detection of mucosal intestinal malignancy. We will further investigate the roles of these promising biomarkers during intestinal tumorigenesis in future. SIGNIFICANCE: CRC is one of the main causes of cancer-related deaths worldwide. Sporadic CRC develops from normal mucosa via adenomas to adenocarcinoma, which provides a long screening window for about 5-10 years. We adopt the metabolic analysis of extensive targeted metabolic technology. The main purpose of the metabolic group analysis is to detect and screen the different metabolites, thereby performing related functional prediction and analysis of the differential metabolites. In our study, 30 samples are selected, divided into 3 groups for metabolic analysis, and 238 metabolites are elected. In 238 metabolites, we find that CRA patients have 72 different metabolites compared with health control. Compared with health control, CRC have 73 different metabolites. Compared with CRA and CRC patients, there are 20 different metabolites. The annotation results of the significantly different metabolites are classified according to the KEGG pathway type. The potential metabolites of tumor growth stage (including patients with CRA and CRC) are found, such as A-d-glucose, D-mannose, N-acetyl-D-glucosamine, L-cystine, sarcosine, TXB 2, 12-Hete and chenodeoxycholic acid. Compared with CRA patients, CRC patients had significantly higher 3,4,5-trimethoxybenzoic acid level. It is prompted to use serum different metabolites to screen CRC to provide new possibilities.

Detection rates of colorectal neoplasia during colonoscopies and their associated factors in the SCREESCO study

BACKGROUND AND AIM

Colonoscopy quality, including lesion detectability, is variable, and factors influencing lesion detection are not fully understood. This study investigated lesion detection rates during colonoscopies and the associated factors in the SCREEning of Swedish COlons (SCREESCO) study.

METHODS

In this cross-sectional analysis of data from SCREESCO, a large-scale randomized controlled trial of colorectal cancer screening in the Swedish population aged 60 years, we assessed data of first-time colonoscopies performed in both colonoscopy and fecal immunochemical test (FIT) arms.

RESULTS

This study included 16 552 individuals. The adenoma detection rate was 23.9% and 37.8% in colonoscopy and FIT arms, respectively. Regarding colonoscopy procedures, a withdrawal time ≥ 6 min was associated with higher detection rates of advanced adenomas (adjusted odds ratio [AOR] 2.474, 95% confidence interval [CI] 1.295-4.723), adenomas (2.181, 1.515-3.140), and proximal serrated lesions (pSLs) (1.713, 1.007-2.915). Antispasmodic use was associated with higher detection rates of these lesions and sessile serrated lesions (SSLs) (AOR, 95% CI: 1.523, 1.295-1.791; 1.361, 1.217-1.522; 1.450, 1.247-1.687; and 1.810, 1.512-2.167, respectively). Insertion time > 20 min was related to lower detection rates of adenomas, pSLs, and SSLs (AOR, 95% CI: 0.753, 0.639-0.887; 0.640, 0.495-0.828; and 0.704, 0.518-0.955, respectively). The relationship between a recent period and higher detection rates of pSLs and SSLs was also demonstrated.

CONCLUSION

Lesion detectability in SCREESCO was mostly acceptable with room for improvement. In addition to sufficient withdrawal time, antispasmodic use and acquiring skills enabling short insertion time may improve lesion detection.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT02078804.

[Quality Assurance of Screening Colonoscopy in Austria and Europe]

Die Vorsorgekoloskopie als effizientes Tool zur Reduktion von Kolorektalkarzinominzidenz und -mortalität ist nur dann effektiv, wenn sie unter hohen Qualitätsstandards durchgeführt wurde. Die European Society for Gastrointestinal Endoscopy gibt hierbei Key Performance Measures, wie die Adenomentdeckungsrate, die Zökumerreichsrate und die Rate an adäquater Vorbereitungsqualität, vor, auf die beim Screening geachtet werden sollten. Das „Qualitätszertifikat Darmkrebsvorsorge“, das als Qualitätssicherungsprogramm auf freiwilliger Basis von der Österreichischen Gesellschaft für Gastroenterologie und Hepatologie gemeinsam mit dem Dachverband der österreichischen Sozialversicherungsträger und der Österreichischen Krebshilfe für Endoskopiker:innen in ganz Österreich ins Leben gerufen wurde, überprüft diese Qualitätsparameter. Es wird ein Darmkrebsscreening auf höchsten Standards angestrebt, um somit die besten Outcomes für Patient:innen zu erzielen. Auch europaweit ist das Interesse an einer qualitätsgesicherten Vorsorgekoloskopie groß: Viele Länder, wie z. B. die Niederlande, Norwegen und das Vereinigte Königreich haben Programme, um die Qualität des Screenings zu überwachen und zu verbessern.

Effect of Colonoscopy Screening on Risks of Colorectal Cancer and Related Death

BACKGROUND

Although colonoscopy is widely used as a screening test to detect colorectal cancer, its effect on the risks of colorectal cancer and related death is unclear.

METHODS

We performed a pragmatic, randomized trial involving presumptively healthy men and women 55 to 64 years of age drawn from population registries in Poland, Norway, Sweden, and the Netherlands between 2009 and 2014. The participants were randomly assigned in a 1:2 ratio either to receive an invitation to undergo a single screening colonoscopy (the invited group) or to receive no invitation or screening (the usual-care group). The primary end points were the risks of colorectal cancer and related death, and the secondary end point was death from any cause.

RESULTS

Follow-up data were available for 84,585 participants in Poland, Norway, and Sweden - 28,220 in the invited group, 11,843 of whom (42.0%) underwent screening, and 56,365 in the usual-care group. A total of 15 participants had major bleeding after polyp removal. No perforations or screening-related deaths occurred within 30 days after colonoscopy. During a median follow-up of 10 years, 259 cases of colorectal cancer were diagnosed in the invited group as compared with 622 cases in the usual-care group. In intention-to-screen analyses, the risk of colorectal cancer at 10 years was 0.98% in the invited group and 1.20% in the usual-care group, a risk reduction of 18% (risk ratio, 0.82; 95% confidence interval [CI], 0.70 to 0.93). The risk of death from colorectal cancer was 0.28% in the invited group and 0.31% in the usual-care group (risk ratio, 0.90; 95% CI, 0.64 to 1.16). The number needed to invite to undergo screening to prevent one case of colorectal cancer was 455 (95% CI, 270 to 1429). The risk of death from any cause was 11.03% in the invited group and 11.04% in the usual-care group (risk ratio, 0.99; 95% CI, 0.96 to 1.04).

CONCLUSIONS

In this randomized trial, the risk of colorectal cancer at 10 years was lower among participants who were invited to undergo screening colonoscopy than among those who were assigned to no screening. (Funded by the Research Council of Norway and others; NordICC ClinicalTrials.gov number, NCT00883792.).

Single CT Appointment for Double Lung and Colorectal Cancer Screening: Is the Time Ripe?

Annual screening of lung cancer (LC) with chest low-dose computed tomography (CT) and screening of colorectal cancer (CRC) with CT colonography every 5 years are recommended by the United States Prevention Service Task Force. We review epidemiological and pathological data on LC and CRC, and the features of screening chest low-dose CT and CT colonography comprising execution, reading, radiation exposure and harm, and the cost effectiveness of the two CT screening interventions. The possibility of combining chest low-dose CT and CT colonography examinations for double LC and CRC screening in a single CT appointment is then addressed. We demonstrate how this approach appears feasible and is already reasonable as an opportunistic screening intervention in 50–75-year-old subjects with smoking history and average CRC risk. In addition to the crucial role Computer Assisted Diagnosis systems play in decreasing the test reading times and the need to educate radiologists in screening chest LDCT and CT colonography, in view of a single CT appointment for double screening, the following uncertainties need to be solved: (1) the schedule of the screening CT; (2) the effectiveness of iterative reconstruction and deep learning algorithms affording an ultra-low-dose CT acquisition technique and (3) management of incidental findings. Resolving these issues will imply new cost-effectiveness analyses for LC screening with chest low dose CT and for CRC screening with CT colonography and, especially, for the double LC and CRC screening with a single-appointment CT.

Colorectal cancer screening with fecal immunochemical testing or primary colonoscopy: An analysis of health equity based on a randomised trial

BACKGROUND

We have addressed health equity attained by fecal immunochemical testing (FIT) and primary colonoscopy (PCOL), respectively, in the randomised controlled screening trial SCREESCO conducted in Sweden.

METHODS

We analysed data on the individuals recruited between March 2014, and March 2020, within the study registered with ClinicalTrials.gov, NCT02078804. Swedish population registry data on educational level, household income, country of birth, and marital status were linked to each 60-year-old man and woman who had been randomised to two rounds of FIT 2 years apart (n = 60,123) or once-only PCOL (n = 30,390). Furthermore, we geo-coded each study individual to his/her residential area and assessed neighbourhood-level data on deprivation, proportion of non-Western immigrants, population density, and average distance to healthcare center for colonoscopy. We estimated adjusted associations of each covariate with the colonoscopy attendance proportion out of all invited to respective arms; ie, the preferred outcome for addressing health equity. In the FIT arm, the test uptake and the colonoscopy uptake among the test positives were considered as the secondary outcomes.

FINDINGS

We found a marked socioeconomic gradient in the colonoscopy attendance proportion in the PCOL arm (adjusted odds ratio [95% credibility interval] between the groups categorised in the highest vs. lowest national quartile for household income: 2·20 [2·01-2·42]) in parallel with the gradient in the test uptake of the FIT × 2 screening (2·08 [1·96-2·20]). The corresponding gradient in the colonoscopy attendance proportion out of all invited to FIT was less pronounced (1·29 [1·16-1·42]), due to higher proportions of FIT positives in socioeconomically disadvantaged groups.

INTERPRETATION

The unintended risk of exacerbating inequalities in health by organised colorectal cancer screening may be higher with a PCOL strategy than a FIT strategy, despite parallel socioeconomic gradients in uptake.

FUNDING

This work was supported by the Swedish Cancer Society under Grant 20 0719. CB and US provided economic support from the Swedish Research Council for Health, Working life, and Welfare under Grant 2020-00962.

Different information needs-The major reasons for calling the helpline when invited to colorectal cancer screening

INTRODUCTION

This study pertains to the design of a decision aid (DA) to shed light on information and support needs in colorectal cancer screening, with the aim to explore the calling patterns to the Screening of Swedish Colons (SCREESCO) study's helpline.

METHODS

A cross-sectional study was conducted with data from documented telephone calls to the SCREESCO study, including individuals, 59-60 years, randomized to colonoscopy or high sensitive faecal immunochemical test (FIT).

RESULTS

More than 2000 calls (women 58.5%; colonoscopy 59%) were analysed. Calling patterns: unsubscribing from screening, confirmation of participation, logistical concerns about the screening procedure, counselling, and FIT screening difficulties or in need of a new FIT test. Comorbidity was the most frequent reason for unsubscribing and most of the counselling calls included questions about the FIT test or the colonoscopy.

CONCLUSION

Most of the calls to the helpline seemed to be related to individuals' lack of understanding about the organization of the screening programme and the screening procedure. Therefore, we find it important to further stress the tailoring part in our DA developing process, that is, provide limited information initially, with the possibility of access to more, if desired by the individual, still with respect to the individual's needs, health and digital literacy.

PATIENT AND PUBLIC CONTRIBUTION

Individuals representing the public and invited to SCREESCO participated since we analysed their calls to the helpline. The findings will contribute to our continued work with the DA where the public will contribute and participate.