Recommendations on Fecal Immunochemical Testing to Screen for Colorectal Neoplasia: A Consensus Statement by the US Multi-Society Task Force on Colorectal Cancer

Is annual screening by fecal immunochemical test necessary after a recent colonoscopy?

Objective

The population-based colorectal cancer screening guidelines in Japan recommend an annual fecal immunochemical test (FIT). However, there is no consensus on the need for annual FIT screening for patients who recently performed a total colonoscopy (TCS). Therefore, we evaluated the repeated TCS results for patients with positive FIT after a recent TCS to assess the necessity of an annual FIT.

Methods

We reviewed patients with positive FIT in opportunistic screening from April 2017 to March 2022. The patients were divided into two groups: those who had undergone TCS within the previous 5 years (previous TCS group) and those who had not (non-previous TCS group). We compared the detection rates of advanced neoplasia and colorectal cancer between the two groups.

Results

Of 671 patients, 151 had received TCS within 5 years and 520 had not. The detection rates of advanced neoplasia in the previous TCS and non-previous TCS groups were 4.6% and 12.1%, respectively (p < 0.01), and the colorectal cancer detection rates were 0.7% and 1.5%, respectively (no significant difference). The adenoma detection rates were 33.8% in the previous TCS group and 40.0% in the non-previous TCS group (no significant difference).

Conclusions

Only a few patients were diagnosed with advanced neoplasia among the patients with FIT positive after a recent TCS. For patients with adenomatous lesions on previous TCS, repeated TCS should be performed according to the surveillance program without an annual FIT. The need for an annual FIT for patients without adenomatous lesions on previous TCS should be prospectively assessed in the future.

Retrospective analysis of preoperative tumor marker levels in rectal cancer patients: Implications for diagnosis

BACKGROUND

Early detection of rectal cancer poses significant challenges. Current diagnostic methods, including colonoscopy, imaging techniques, and fecal tests, have limitations such as invasiveness, cost, and varying sensitivity. This study evaluated the diagnostic value of preoperative serum tumor markers in rectal cancer patients.

AIM

To investigate the value of a multi-marker approach for the preoperative diagnosis of rectal cancer.

METHODS

A retrospective analysis of 250 patients diagnosed with rectal cancer between July 2022 and July 2024 was conducted. Preoperative alpha-fetoprotein levels, carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), CA19-9, CA15-3, and CA72-4 were analyzed. All blood samples were collected under standardized conditions, including fasting status and proper storage methods, within two weeks before surgery. Diagnostic performance was assessed using receiver operating characteristic curve analysis. Correlations among clinicopathological features were also evaluated.

RESULTS

CEA demonstrated the highest diagnostic performance among individual tumor markers with an area under the curve (AUC) of 0.78 [95% confidence interval (CI): 0.73-0.83]. However, a combination of CEA, CA19-9, and CA72-4 showed superior performance, achieving an AUC of 0.87 (95%CI: 0.83-0.91). Significant correlations were observed between CEA levels and several clinicopathological features, including tumor stage (P < 0.001), lymph node involvement (P = 0.002), and distant metastasis (P < 0.001). Furthermore, in a subgroup analysis of patients diagnosed after July 2022, the integration of fecal occult blood testing with the tumor marker panel (CEA + CA19-9 + CA72-4) significantly improved diagnostic accuracy, increasing the AUC to 0.91 (95%CI: 0.86-0.96).

CONCLUSION

A multimarker approach combining CEA, CA19-9, and CA72-4 with fecal occult blood testing enhances the preoperative assessment of patients with rectal cancer. These findings suggest potential improvements in risk stratification and management of patients with rectal cancer.

Participation and Yield in Multiple Rounds of Colorectal Cancer Screening Based on Fecal Immunochemical Test: A Systematic Review and Meta-Analysis

INTRODUCTION

The evidence on the cumulative participation and yield in multiple rounds of colorectal cancer (CRC) screening based on fecal immunochemical test is sparse. We aimed to assess the trends in participation and detection for advanced colorectal neoplasm under different screening intervals in multiround fecal immunochemical testing-based CRC screening by synthesizing the current available evidence.

METHODS

PubMed, Embase, and Cochrane were retrieved from January 1, 2002, to April 16, 2024, for potential eligible studies, and then, we synthesized participation and advanced colorectal neoplasm detection rates for each screening round, along with their respective 95% confidence intervals (CIs).

RESULTS

Nineteen studies involving a total of 2,296,071 individuals were included. As screening rounds increased, participation exhibited a gradual consistent increase, reaching 78.45% and 74.97% for annual and biennial screening strategies. For annual screening, the cumulative detection rates for 3 rounds were 1.38% (95% CI: 1.18%-1.63%), 1.95% (95% CI: 1.72%-2.21%), and 2.50% (95% CI: 2.29%-2.72%), respectively. For biennial screening, the cumulative detection rates for 4 rounds were 2.22% (95% CI: 1.22%-3.22%), 3.44% (95% CI: 2.06%-4.82%), 4.26% (95% CI: 2.70%-5.83%), and 5.10% (95% CI: 3.28%-7.29%), respectively. Notably, the per-round detection rate of advanced colorectal neoplasms declined yet as the screening progressed.

DISCUSSION

In population-based CRC screening programs, the participation exhibited a slow upward trend for both screening strategies, but the incremental benefits in CRC detection gradually diminished. Tailored strategies, such as extending intervals for individuals with multiple negative fecal immunochemical testing results, might optimize effectiveness and cost-efficiency in population-based CRC screening.

Housing Status and Cancer Screening in US Veterans

BACKGROUND

Cancer is a leading cause of death in people experiencing homelessness, who are more commonly diagnosed with late-stage disease and have poorer survival after diagnosis than housed.

OBJECTIVE

To characterize the incidence and timeliness of colorectal and breast cancer screening in a national sample of Veterans.

DESIGN

Retrospective, matched cohort study from 2011 to 2021 in a national sample of Veterans receiving care from the Veterans Health Administration (VA).

PARTICIPANTS

Each Veteran experiencing homelessness was matched to three housed Veterans with the same age, gender, clinic location, and month and year of outpatient clinic appointment.

EXPOSURE

We classified Veterans as homeless if they had any homeless indicator at the matched clinic visit or in the 12 months prior and all others as housed.

MAIN MEASURES

Our primary outcomes were being up to date on screening, receiving a biopsy following a positive screen and timeliness of biopsy. We assessed the association between housing status and our outcomes using conditional Poisson regression models with generalized estimating equations, adjusting for race, ethnicity, marital status, Charlson Comorbidity Index, smoking status, and mental health comorbidities.

KEY RESULTS

Our sample included 2,580,640 Veterans, with 1,935,480 housed and 645,160 experiencing homelessness. Patients experiencing homelessness had a 16% lower adjusted incidence rate ratio (aIRR) of being up to date with colorectal cancer screening when compared to housed (aIRR 0.84, 95%CI 0.83-0.84; p<0.001) and a 13% lower aIRR for breast cancer (aIRR 0.87, 95%CI 0.86-0.88; p<0.001). Following a positive stool-based test, patients experiencing homelessness had a 12% lower aIRR of undergoing diagnostic colonoscopy compared to housed (aIRR 0.88, 95%CI 0.84-0.92; p<0.001). Time to biopsy was similar between groups for both cancer types.

CONCLUSIONS

Veterans experiencing homelessness were less commonly screened for cancer than a matched housed cohort. However, screening rates in this group were higher than in non-Veteran homeless populations. The VA system may offer insights into providing preventative care for this population.

Fecal Immunochemical Testing for Colorectal Cancer Prevention in Two Public Hospitals

INTRODUCTION

The fecal immunochemical test (FIT) is highly effective in reducing colorectal cancer (CRC) mortality, but patient adherence to the screening process remains questionable. We present preliminary findings from a quality improvement (QI) initiative, in order to assess screening adherence and findings.

METHODS

All FIT specimens in a 30-month period were retrospectively examined. Patients with positive results were included, and information was collected via electronic medical record, including QI measures such as colonoscopy completion and findings. All data were de-identified. Patients were divided into "asymptomatic group" and "symptomatic group" based on clinical manifestations. Adherence and findings were analyzed.

RESULTS

FIT results were positive in 174 out of 2400 specimens. Colonoscopy was performed in 47.6% of all FIT-positive cases after a median interval of 5.5 (interquartile range, IQR 3-10) months, with 10% having CRC, 51.3% having adenomas, and 17.5% having advanced adenomas. Of all nine patients who had CRC, seven were in the symptomatic group. All five advanced cancers were found in the symptomatic group. Patients who actually completed colonoscopy were significantly younger than those who did not (median 61.5 years, IQR 56.5-69 years, vs. 64.5 years, IQR 59-71 years, P = 0.048). Patient-related reasons, primarily refusal, accounted for 65.9% of unperformed colonoscopies. No significant difference was found in adherence and yield between asymptomatic and symptomatic groups.

CONCLUSION

Prevalence of colorectal adenomas and cancers is high in FIT-positive patients. A substantial number of CRCs and potentially preventable CRCs must have been missed because of low adherence rate, especially in older patients. Improving adherence to CRC screening in public hospitals requires enhanced patient engagement.

Application of the Colorectal Cancer (CRC) Screening Guiding Principles for Non-invasive Testing to Multi-target Stool DNA: A Case Study

A significant lack of participation in colorectal cancer (CRC) screening programs in the United States limits the impact of screening to reduce morbidity and mortality. Recently a group of experts in CRC screening defined the Guiding Principles for Noninvasive Testing (GPNIT). GPNIT pathway is intended to serve as a step by step guide for study design to ultimately lead to implementation and integration of a potentially clinically appropriate CRC screening test. Multi-target stool DNA (MT-sDNA) test usage for CRC screening has increased significantly recently in the United States. Here, the key studies in the development of MT-sDNA as an emerging CRC screening test are placed in context of the GPNIT pathway for CRC screening test development. This case study is meant to be instructive for future test development in CRC screening to achieve ultimately clinically relevant future tests and improve the efficacy of CRC screening.

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.

Rebound in Fecal Testing, Colonoscopy Utilization, and Colorectal Neoplasia Detection During the COVID-19 Pandemic

INTRODUCTION

The COVID-19 pandemic reduced colorectal cancer (CRC) screening, but the rebound in testing and outcomes after the pandemic has not been widely reported. We evaluated CRC test utilization and colorectal neoplasia detection among screening eligible patients in a large health system in 2020 and 2021, compared with 2019 (prepandemic).

METHODS

Using a retrospective cohort study design, fecal immunochemical test (FIT) and colonoscopy utilization, FIT positivity, and neoplasia detection were evaluated annually in 2019-2021 among Kaiser Permanente Northern California patients aged 50-75 years overall and by sex, age, race and ethnicity, and spoken language preference.

RESULTS

Compared with 2019, reductions in FIT, colonoscopy, FIT positivity, and neoplasia detection in 2020 were followed by a strong rebound in 2021 and no subgroups by age and sex or minority subgroups by race and ethnicity or spoken language preference demonstrably lagged in their recovery in 2021. Among White persons and those with an English language preference, there was a small lag in recovery to baseline levels. The overall decline in CRC testing by colonoscopy in 2020 was offset by a lesser decrease in FIT utilization in 2020, and a strong rebound in FIT utilization in 2021 helped to offset the small lag in the rebound in colonoscopies completed in 2021.

DISCUSSION

Findings may help guide organizations looking to improve CRC screening and minimize health care disparities related to national emergencies such as pandemics. Long-term studies are needed to evaluate how pandemic-related changes in CRC screening practices will affect future CRC outcomes.

Diagnostic accuracy of the faecal immunochemical test and volatile organic compound analysis in detecting colorectal polyps: meta-analysis

BACKGROUND

For the early detection of colorectal cancer, it is important to identify the premalignant lesions to prevent cancer development. Non-invasive testing methods such as the faecal immunochemical test are well established for the screening and triage of patients with suspected colorectal cancer but are not routinely used for polyps. Additionally, the role of volatile organic compounds has been tested for cancer detection. The aim of this review was to determine the diagnostic accuracy of the faecal immunochemical test and volatile organic compounds in detecting colorectal polyps.

METHODS

Original articles with diagnostic test accuracy measures for both the faecal immunochemical test and volatile organic compounds for advanced adenomas were included. Four databases including Medical Literature Analysis and Retrieval System Online (MEDLINE), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, and Web of Science were searched. The quality assessment tool for diagnostic accuracy study was used to assess the risk of bias and applicability. Meta-analysis was performed using RStudio® and the combined faecal immunochemical test-volatile organic compounds sensitivity and specificity were computed.

RESULTS

Twenty-two faecal immunochemical tests and 12 volatile organic compound-related articles were included in the systematic review whilst 18 faecal immunochemical tests and eight volatile organic compound-related studies qualified for the meta-analysis. The estimated pooled sensitivity and specificity of the faecal immunochemical test to diagnose advanced adenoma(s) were 36% (95% c.i. 30 to 41) and 89% (95% c.i. 86 to 91) respectively, with an area under the curve of 0.65, whilst volatile organic compounds pooled sensitivity and specificity was 83% (95% c.i. 70 to 91) and 76% (95% c.i. 60 to 87) respectively, with an area under the curve of 0.84. The combined faecal immunochemical test-volatile organic compounds increased the sensitivity to 89% with a specificity of 67%.

CONCLUSION

Faecal immunochemical testing has a higher specificity but poor sensitivity for detecting advanced adenomas, while volatile organic compound analysis is more sensitive. The combination of both tests enhances the detection rate of advanced adenomas.

Post-colonoscopy upper gastrointestinal malignancies in positive immunochemical fecal occult blood test patients: An Australian data linkage study

BACKGROUND AND AIM

In immunochemical fecal occult blood test (iFOBT) positive subjects, colonoscopy screening can detect colorectal cancers and advanced adenomas, yet most iFOBT-positive subjects find no relevant lower gastrointestinal lesions. Limited data are available on upper gastrointestinal (UGI) cancer risk in iFOBT-positive patients. This study investigated the incidence of UGI malignancies diagnosed within 3 years post-colonoscopy after a positive iFOBT.

METHODS

Retrospective analysis of iFOBT-positive patients aged 50-75 years who underwent a colonoscopy at a single institution. All patients with a diagnosis of UGI cancer within 3 years post-colonoscopy were identified by linking with the Queensland Cancer Register. This was used to compare to the geographical population aged 50-74 years based on the Australian Bureau of Statistics and Queensland Cancer Council data.

RESULTS

From 1748 eligible participants, 0.23% (95% confidence interval [CI] 0.06-0.58) were diagnosed with UGI cancer within 3 years post-colonoscopy. This indicates an esophageal cancers rate of 114.42 per 100 000 (95% CI 100.56-298.28) and gastric cancer rate of 57.21 per 100 000 (95% CI 55.76-261.12). Of the patients with a UGI cancer, 75% would have had an unexplained iFOBT. Annual incidence for the same geographic region, ages, and period for the combined esophageal and gastric cancer was 36.08 per 100 000 (95% CI 32.87-39.52).

CONCLUSIONS

Among individuals with a positive iFOBT in a bowel cancer screening program, the rates of gastric and esophageal cancers were 2.7 and 7.5 times higher than the general population. Adding gastroscopy to a colonoscopy for iFOBT-positive patients in cancer surveillance programs may be justifiable.

Association between time to colonoscopy after positive fecal testing and colorectal cancer outcomes in Alberta, Canada

OBJECTIVE

To quantify the associations between time to colonoscopy after a positive fecal immunochemical test (FIT+) and colorectal cancer (CRC)-related outcomes in the context of a provincial, population-based CRC screening program.

SETTING

Population-based, retrospective cohort study in Alberta, Canada, including Albertans aged 50-74 with at least one FIT+ in 2014-2017.

METHODS

Study outcomes were CRC diagnosis after a FIT+ and a diagnostic follow-up colonoscopy in 2014-2019 and CRC stage at diagnosis. Multivariable logistic regression models were used to evaluate the relative risk of any CRC or advanced-stage CRC. Results were presented as crude odds ratio (OR) and adjusted OR (aOR) with 95% confidence intervals (CIs).

RESULTS

Of the 787,967 participants who had a FIT, 63,232 (8%) had a FIT+ and met the study's eligibility criteria. The risk of any CRC or advanced-stage CRC stayed high and was relatively consistent for follow-up colonoscopies performed within 1-12 months of the FIT+. After 12 months, the risk of CRC was considerably higher, particularly for advanced-stage CRC. The OR and aOR for any CRC were 1.40 (95% CI: 1.13-1.73; p < 0.05) and 1.20 (95% CI: 0.96-1.49), respectively, and the OR and aOR for advanced-stage CRC were 1.42 (95% CI: 0.98-2.08) and 0.88 (95% CI: 0.59-1.32), respectively, for colonoscopy follow-up within 12-18 months versus 1-2 months.

CONCLUSIONS

For Albertans who used FIT for CRC screening, a longer time interval between a FIT+ and follow-up colonoscopy, particularly over 12 months, increases the risk of having CRC and decreases the effectiveness of CRC screening programs.

Development of an algorithm combining blood-based biomarkers, fecal immunochemical test, and age for population-based colorectal cancer screening

BACKGROUND AND AIMS

Implementation of screening modalities has reduced the burden of colorectal cancer (CRC), but high false positive rates pose a major problem for colonoscopy capacity. We aimed to create a tailored screening algorithm that expands the fecal immunochemical test (FIT) with a blood specimen and current age to improve selection of individuals for diagnostic colonoscopy.

METHODS

In this prospective multicenter study, 8 blood-based biomarkers (carcinoembryonic antigen, ferritin, high-sensitivity C-reactive protein, human epididymis protein 4, Cyfra21-1, hepsin, interleukin 8, and osteoprotegerin) were investigated in 1977 FIT-positive individuals from the Danish national CRC screening program undergoing follow-up colonoscopy. Specimens were analyzed on Architect i2000, Architect c8000 (both from Abbott, Chicago, Ill, USA), or Luminex xMAP machines (MilliporeSigma, St. Louis, Mo, USA). FIT analyses and blood-based biomarker data were combined with clinical data (ie, age and colonoscopy findings) in a cross-validated logistic regression model (algorithm) benchmarked against a model solely using the FIT result (FIT model) applying different cutoffs for FIT positivity.

RESULTS

The cohort included individuals with CRC (n = 240), adenomas (n = 938), or no neoplastic lesions (n = 799). The cross-validated algorithm combining the 8 biomarkers, quantitative FIT result, and age performed superior to the FIT model in discriminating CRC versus non-CRC individuals (area under the receiver operating characteristic curve, 0.77 vs 0.67, respectively; P < .001). When discriminating individuals with either CRC or high- or medium-risk adenomas versus low-risk adenomas or clean colorectum, the areas under the receiver operating characteristic curve were 0.68 versus 0.64 for the algorithm and FIT model, respectively.

CONCLUSIONS

The algorithm presented here can improve patient allocation to colonoscopy, reducing colonoscopy burden without compromising cancer and adenoma detection rates or vice versa.

FIT as a Comparator for Evaluating the Effectiveness of New Non-invasive CRC Screening Test

Randomized Controlled Trials (RCT) demonstrated that guaiac-based fecal occult blood test (gFOBT), sigmoidoscopy, or colonoscopy are effective at reducing colorectal cancer (CRC) risk and mortality. Even if the impact of fecal immunochemical test (FIT) has not been evaluated within population-based RCT with mortality as the outcome, the results of comparative analyses with gFOBT provide strong indirect evidence of its effectiveness. Extensive information is also available on sensitivity and specificity of FIT, compared with gFOBT. FIT has almost universally replaced gFOBT in organized screening programs worldwide. Using FIT as a comparator is an efficient way to evaluate the effectiveness of new tests, with respect to test performance and relevant intermediate outcomes such as rates of interval cancer and late-stage cancer incidence. Direct comparison with FIT in the pre-screening evaluation of the accuracy of the new test will guide selection of the cut-off of the new test, and document the potential gain in sensitivity. Comparison in cross-sectional single-round screening evaluation can either use paired or parallel designs. Only parallel designs allow direct comparisons of participation rates. Relative accuracy can be derived in both designs with an assumption of similar colorectal cancer and precursor prevalence between groups in parallel designs. Finally, multiple-rounds prospective comparison will document potential effect on risk of CRC and precancerous lesions, and on absolute reductions in late-stage incidence as a proxy of mortality. This paper provides an overview of evidence and rationale for using FIT as a comparator for evaluating new non-invasive tests with repeated testing at short intervals.

Early Onset Colorectal Cancer: Molecular Underpinnings Accelerating Occurrence

The onset of colorectal cancer (CRC) in patients younger than 50 continues to rapidly increase. This study highlights the epidemiologic changes, risk factors, clinical characteristics, and molecular profiles prevalent in early onset CRC patients, and identifies key areas for future research. It has been noted that only a small fraction of early onset CRC cases is attributed to known hereditary mutations and fit the canonical pathway of late-onset colorectal cancer development. To highlight this, we review the genetic and epigenetic modifications specific to early onset CRC. We also discuss the synergetic effect of single-nucleotide polymorphisms and environmental factors on the early onset of CRC. Additionally, we discuss the potential of noninvasive biomarker assays to enhance early detection, screening, diagnosis, and prognostic outcome predictions.

Optimizing tracking and completion of follow-up colonoscopy after abnormal stool tests at health systems participating in the Centers for Disease Control and Prevention's Colorectal Cancer Control Program

PURPOSE

We present findings from an assessment of award recipients' partners from the Centers for Disease Control and Prevention's Colorectal Cancer Control Program (CRCCP). We describe partners' processes of identifying and tracking patients undergoing stool-based screening.

METHODS

We analyzed data from eight CRCCP award recipients purposively sampled and their partner health systems from 2019 to 2023. The data included number of stool-based tests distributed and returned; abnormal findings; referrals and completion of follow-up colonoscopies; and colonoscopy findings. We also report on strategies to improve tracking of stool-based tests and facilitation of follow-up colonoscopies.

RESULTS

Five of eight CRCCP award recipients reported that all or some partner health systems were able to report stool test return rates. Six had health systems that were able to report abnormal stool test findings. Two reported that health systems could track time to follow-up colonoscopy completion from date of referral, while four could report colonoscopy completion but not the timeframe. Follow-up colonoscopy completion varied substantially from 24.2 to 75.5% (average of 47.9%). Strategies to improve identifying and tracking screening focused mainly on the use of electronic medical records; strategies to facilitate follow-up colonoscopy were multi-level.

CONCLUSION

Health systems vary in their ability to track steps in the stool-based screening process and few health systems can track time to completion of follow-up colonoscopy. Longer time intervals can result in more advanced disease. CRCCP-associated health systems participating in this study could support the implementation of multicomponent strategies at the individual, provider, and health system levels to improve tracking and completion of follow-up colonoscopy.

Reducing the Risk of Delayed Colorectal Cancer Diagnoses Through an Ambulatory Safety Net Collaborative

BACKGROUND

An estimated 12 million adults in the United States experience delayed diagnoses and other diagnostic errors annually. Ambulatory safety nets (ASNs) are an intervention to reduce delayed diagnoses by identifying patients with abnormal results overdue for follow-up using registries, workflow redesign, and patient navigation. The authors sought to co-design a collaborative and implement colorectal cancer (CRC) ASNs across various health care settings.

METHODS

A working group was convened to co-design implementation guidance, measures, and the collaborative model. Collaborative sites were recruited through a medical professional liability insurance program and chose to begin with developing an ASN for positive at-home CRC screening or overdue surveillance colonoscopy. The 18-month Breakthrough Series Collaborative ran from January 2022 to July 2023, with sites continuing to collect data while sustaining their ASNs. Data were collected from sites monthly on patients in the ASN, including the proportion that was successfully contacted, scheduled, and completed a follow-up colonoscopy.

RESULTS

Six sites participated; four had an operational ASN at the end of the Breakthrough Series, with the remaining sites launching three months later. From October 2022 through February 2024, the Collaborative ASNs collectively identified 5,165 patients from the registry as needing outreach. Among patients needing outreach, 3,555 (68.8%) were successfully contacted, 2,060 (39.9%) were scheduled for a colonoscopy, and 1,504 (29.1%) completed their colonoscopy.

CONCLUSION

The Collaborative successfully identified patients with previously abnormal CRC screening and facilitated completion of follow-up testing. The CRC ASN Implementation Guide offers a comprehensive road map for health care leaders interested in implementing CRC ASNs.

Antithrombotic drug use does not affect the fecal immunochemical test PPV for colorectal cancer, but warfarin may have an impact in a Japanese cohort

BACKGROUND

The fecal immunochemical test (FIT) is used for colorectal cancer (CRC) screening. Patients on antithrombotic drugs (ATs) are often screened for CRC, but the effect of ATs on FIT results is controversial.

METHODS

We divided individuals with FIT-positive results into two groups, patients treated with and without ATs, and retrospectively compared invasive CRC rates, advanced neoplasia detection rates (ANDRs), adenoma detection rates (ADRs), and polyp detection rates (PDRs) between the two groups. We evaluated the factors influencing the FIT positive predictive value (PPV) using propensity matching, adjusting for age, sex, and bowel preparation.

RESULTS

We enrolled 2327 individuals (54.9% male; mean age, 66.7  ±  12.7 years). We grouped 463 individuals into the AT user group and 1864 into the nonuser group. Patients in the AT user group were significantly older and more likely to be male. After propensity score matching for age, sex, and Boston bowel preparation scale, the ADR and PDR in the AT user group were significantly lower than those in the nonuser group. Univariate logistic analysis revealed that multiple AT use (odds ratio [OR]: .39, p < 0.001) had the lowest OR for FIT PPV, followed by age- and sex-adjusted factors for the ADR and any AT use (OR: .67, p = 0.0007). No significant factors related to AT use were observed among age-adjusted predictive factors for invasive CRC, but warfarin use was a borderline significant positive predictive factor (OR: 2.23, p = 0.059).

CONCLUSION

AT use may not affect the PPV for detecting invasive CRC in patients with positive FIT results, but warfarin may have an impact.

Application of machine-learning model to optimize colonic adenoma detection in India

AIMS

There is limited data on the prevalence and risk factors of colonic adenoma from the Indian sub-continent. We aimed at developing a machine-learning model to optimize colonic adenoma detection in a prospective cohort.

METHODS

All consecutive adult patients undergoing diagnostic colonoscopy were enrolled between October 2020 and November 2022. Patients with a high risk of colonic adenoma were excluded. The predictive model was developed using the gradient-boosting machine (GBM)-learning method. The GBM model was optimized further by adjusting the learning rate and the number of trees and 10-fold cross-validation.

RESULTS

Total 10,320 patients (mean age 45.18 ± 14.82 years; 69% men) were included in the study. In the overall population, 1152 (11.2%) patients had at least one adenoma. In patients with age > 50 years, hospital-based adenoma prevalence was 19.5% (808/4144). The area under the receiver operating curve (AUC) (SD) of the logistic regression model was 72.55% (4.91), while the AUCs for deep learning, decision tree, random forest and gradient-boosted tree model were 76.25% (4.22%), 65.95% (4.01%), 79.38% (4.91%) and 84.76% (2.86%), respectively. After model optimization and cross-validation, the AUC of the gradient-boosted tree model has increased to 92.2% (1.1%).

CONCLUSIONS

Machine-learning models may predict colorectal adenoma more accurately than logistic regression. A machine-learning model may help optimize the use of colonoscopy to prevent colorectal cancers.

TRIAL REGISTRATION

ClinicalTrials.gov (ID: NCT04512729).

Repeat Faecal Immunochemical Testing for Colorectal Cancer Detection in Symptomatic and Screening Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Faecal immunochemical testing (FIT) is widely used in bowel screening programmes and assessing symptomatic patients for suspected colorectal cancer (CRC). The evidence for single test performance of FIT in both settings is considerable; however, the use of a repeat test to increase sensitivity remains uncertain. We aimed to review what increase in test positivity would be generated by additional FITs, whether a repeated FIT detects previously missed CRC and advanced colorectal neoplasia (ACRN), and to estimate the sensitivity of double-FIT strategies to diagnose CRC and ACRN.

METHODS

A systematic search of MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) was performed using key search terms. Studies reporting the use of more than one FIT in the same screening round or planned assessment of a single symptomatic patient episode were included. Studies were categorised by the reported study population into asymptomatic, mixed (cohorts of combined asymptomatic, symptomatic, or high-risk surveillance), or symptomatic cohorts.

RESULTS

A total of 68 studies were included for analysis (39 asymptomatic, 21 mixed, 7 symptomatic, and 1 study with discrete asymptomatic and symptomatic data). At a threshold of 10 µg Hb/g, the two-test positivity ranged between 8.1 and 34.5%, with an increase from the second test of 3-9.2 percentage points. Four out of five studies comparing one versus two tests for diagnosing CRC at 10 µg Hb/g identified additional cases with the second test, with a minimum of 50% reduction in missed CRC. At a threshold of 20 µg Hb/g, the second test increased the positivity by 1.3-6.7 percentage points, with a two-test positivity of between 5.1 and 25.0%. Using a threshold of 20 µg Hb/g, five out of seven studies had a 25% reduction in missed CRC. A meta-analysis estimated the double-FIT sensitivity at 10 µg Hb/g for CRC in mixed-risk and symptomatic cohorts to be 94% and 98%, respectively.

CONCLUSIONS

Repeated use of FIT helps to diagnose more cases of CRC with a moderate increase in positivity. A double-FIT strategy at 10 µg Hb/g in mixed and symptomatic cohorts has a very high sensitivity for CRC.

Risk Factors for Suboptimal Colon Cancer Diagnosis and Management at a Safety-Net Hospital System

INTRODUCTION

Colon cancer (CC) is the second leading cause of cancer-related deaths in the United States. Quality measures have been introduced by the American Gastroenterological Association and Commission on Cancer for optimal management of CC. In this study, we sought to identify factors that may hinder the timely diagnosis and treatment of CC at a safety-net hospital system.

METHODS

Retrospective chart review was performed for patients aged ≥18 y diagnosed with CC from 2018 to 2021. Primary outcomes were time from positive fecal immunochemical test to colonoscopy, time from diagnosis to surgery, and time from diagnosis to adjuvant chemotherapy. Secondary end points were demographic characteristics associated with suboptimal outcomes in any of the above measures.

RESULTS

One hundred ninety patients were diagnosed with nonmetastatic CC. The majority were Hispanic and non-English-speaking. 74.1% of patients with a positive fecal immunochemical test received a colonoscopy within 180 d. 59.6% of nonemergent cases received surgery within 60 d of diagnosis. 77% of those eligible received adjuvant chemotherapy within 120 d of diagnosis. No clinically significant demographic factor was associated with delay in colonoscopy, surgery, or adjuvant chemotherapy. Most frequent cause of delay in surgery (38.0%) was optimization of comorbidities. Most frequent cause of delay in adjuvant chemotherapy (71.4%) was delay in surgery itself.

CONCLUSIONS

No clinically significant demographic factor was associated with experiencing delays in diagnostic colonoscopy, surgery, or adjuvant chemotherapy.

SIED-GISCOR recommendations for colonoscopy in screening programs: Part I - Diagnostic

The implementation of FIT programs reduces incidence and mortality from CRC in the screened subjects. The ultimate efficacy for CRC morbidity and mortality prevention in a FIT program depends on the colonoscopy in FIT+ subjects that has the task of detecting and removing these advanced lesions. Recently, there has been growing evidence on factors that influence the quality of colonoscopy specifically withing organized FIT programs, prompting to dedicated interventions in order to maximize the benefit/harm ratio of post-FIT colonoscopy. This document focuses on the diagnostic phase of colonoscopy, providing indications on how to standardise colonoscopy in FIT+ subjects, regarding timing of examination, management of antithrombotic therapy, bowel preparation, competence and sedation.

Feasibility and Colonoscopy Yield Using the Fecal Immunochemical Test (FIT)-Based Colorectal Cancer Screening in a Latin America Country

BACKGROUND & AIMS

Organized colorectal cancer (CRC) screening is not widely practiced in Latin America and the results of regional studies may help overcome barriers for implementation of national screening programs. We aimed to describe the implementation and findings of a fecal immunochemical test (FIT)-based program in Brazil.

METHODS

In a prospective population-based study, asymptomatic individuals (50-75 years old) from Sao Paulo city were invited to undergo FIT for CRC screening. Participants with positive FIT (≥10 μg Hb/g feces) were referred for colonoscopy. Subjects were classified into groups according to the presence of CRC, precursor lesions, and other benign findings, possibly related to bleeding.

RESULTS

Of a total of 9881 subjects, 7.8% had positive FIT and colonoscopy compliance was 68.9% (n = 535). Boston scale was considered adequate in 99% and cecal intubation rate was 99.4%. CRC was diagnosed in 5.9% of the cases, adenoma in 63.2%, advanced adenoma in 31.4%, and advanced neoplasia in 33.0%. Age was positively associated with CRC (P = .03). Higher FIT concentrations were associated with increased detection of CRC (P < .008), advanced adenoma (P < .001), and advanced neoplasia (P < .001).

CONCLUSIONS

Implementation of a FIT-based CRC screening program was feasible in a low-resource setting, and there was a high yield for neoplasia in individuals with a positive FIT. This approach could be used as a model to plan and disseminate organized CRC screening more broadly in Brazil and Latin America.

Evaluating colonoscopy quality by performing provider type

BACKGROUND

Colorectal cancer is the third most diagnosed cancer and the second leading cause of cancer death in the United States. Colonoscopy is an essential tool for screening, used as a primary approach and follow-up to an abnormal stool-based colorectal cancer screening result. Colonoscopy quality is often measured with 4 key indicators: bowel preparation, cecal intubation, mean withdrawal time, and adenoma detection. Colonoscopies are most often performed by gastroenterologists (GI), however, in rural and medically underserved areas, non-GI providers often perform colonoscopies. This study aims to evaluate the quality and safety of screening colonoscopies performed by non-GI practitioner, comparing their outcomes with those of GI providers.

METHODS

Descriptive statistics were used to characterize the study population. Results for quality indicators were stratified by provider type and compared. Statistical significance was determined using a P value of less than .05 as the threshold for all comparisons; all P values were 2-sided.

RESULTS

No statistical difference was found when comparing performance by provider type. Median performance for gastroenterologists, general surgeons, and family medicine providers ranged from 98% to 100% for cecal intubation; 97.4% to 100% for bowel preparation; 57.4% to 88.9% for male adenoma detection rate; 47.7% to 62.13% for female adenoma detection rate; and 0:12:10 to 0:20:16 for mean withdrawal time. All provider types met and exceeded the goal metric for each of the quality indicators (P < .001).

CONCLUSIONS

As a result of this analysis, we can expect non-GI practitioner to perform colonoscopies with similar quality to GI practitioner given the performance outcomes for the key quality metrics.

The Impact of potential 'confounders' on the diagnostic sensitivity of circulating free DNA in management of FIT+ patients: a pilot study

Cell-free DNA (cfDNA) has long been established as a useful diagnostic and prognostic tool in a variety of clinical settings, ranging from infectious to cardiovascular and neoplastic diseases. However, non-neoplastic diseases can act as confounders impacting on the amount of cfDNA shed in bloodstream and on technical feasibility of tumour derived free circulating nucleic acids selecting patients with cancer. Here, we investigated the potential impact of other pathological processes in the clinical stratification of 637 FIT+ patients. A single and multiple logistic regression yielded similar results. Crude sensitivity was 75.9% versus adjusted sensitivity of 74.1%, relative risk 0.9761 (0.8516 to 1.1188), risk difference 0.0181 (-0.0835 to 0.1199) and OR 0.9079 (0.5264 to 1.5658). Potential confounding effect from other source of cfDNA plays a pivotal role in the clinical stratification of FIT+ patients.

Performance of OC-Auto Micro 80 Fecal Immunochemical Test in an Integrated Academic-Community Health System

GOALS

We aimed to determine the performance of the OC-Auto Micro 80 fecal immunochemical test (FIT) in an average-risk population receiving care in an integrated, academic-community health system.

BACKGROUND

The FIT is the most used colorectal cancer (CRC) screening test worldwide. However, many Food and Drug Administration-cleared FIT products have not been evaluated in clinical settings.

STUDY

We performed a retrospective cohort study of patients (50 to 75 y old) in the University of Washington Medicine health care system who were screened for CRC by OC-Auto Micro 80 FIT between March 2016 and September 2021. We used electronic health records to extract patient-level and clinic-level factors, FIT use, colonoscopy, and pathology findings. The primary outcomes were the FIT positivity rate and neoplasms detected at colonoscopy. Secondary outcomes were FIT positivity by sex and safety-net versus non-safety-net clinical settings.

RESULTS

We identified 39,984 FITs completed by 26,384 patients; 2411 (6.0%) had a positive FIT result (>100 ng/mL of hemoglobin in buffer), and 1246 (51.7%) completed a follow-up colonoscopy. The FIT positive rate was 7.0% in men and 5.2% in women ( P <0.01). Among those who completed a colonoscopy after an abnormal FIT result, the positive predictive value for CRC, advanced adenoma, and advanced neoplasia was 3.0%, 20.9%, and 23.9%, respectively.

CONCLUSIONS

In a retrospective analysis of a large heterogeneous population, the OC-Auto Micro 80 FIT for CRC screening demonstrated a positivity rate of 6.0% and a positive predictive value for CRC of 3.0%.

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.

Racial/ethnic and socioeconomic disparities in colorectal cancer screening in a large organization with universal insurance before and during the coronavirus disease 2019 pandemic

OBJECTIVES

Israel is regarded as a country with a developed economy and a moderate income inequality index. In this population-based study, we aimed to measure the inequalities in colorectal cancer screening within Clalit Health, an organization with universal insurance, before and during the coronavirus disease 2019 pandemic.

SETTING

Retrospective analysis within Clalit Health Services, Israel.

METHODS

We evaluated the rate of being up to date with screening (having a colonoscopy within 10 years or a fecal occult blood test within 1 year) and the colonoscopy completion rate (having a colonoscopy within 6 months of a positive fecal occult blood test) among subjects aged 50-75 in 2019-2021.

RESULTS

In 2019, out of 918,135 subjects, 61.3% were up to date with screening; high socioeconomic status: 65.9% (referent), medium-socioeconomic status: 60.1% (odds ratio 0.81, 95% confidence interval 0.80-0.82), low-socioeconomic status: 59.0% (odds ratio 0.75, 95% confidence interval 0.74-0.75); Jews: 61.9% (referent), Arabs: 59.7% (odds ratio 0.91, 95% confidence interval 0.90-0.92), Ultraorthodox-Jews: 51.7% (odds ratio 0.77, 95% confidence interval 0.75-0.78). Out of 21,308 with a positive fecal occult blood test, the colonoscopy completion rate was 51.8%; high-socioeconomic status: 59.8% (referent), medium-socioeconomic status: 54.1% (odds ratio 0.79, 95% confidence interval 0.73-0.86), low-socioeconomic status: 45.5% (odds ratio 0.60, 95% confidence interval 0.56-0.65); Jews: 54.7% (referent), Ultraorthodox-Jews: 51.4% (odds ratio 0.91, 95% confidence interval 0.90-0.92), Arabs: 44.7% (odds ratio 0.77, 95% confidence interval 0.75-0.78). In 2020-2021, there was a slight drop in the rate of being up to date with screening, while most of the discrepancies were kept or slightly increased with time.

CONCLUSIONS

We report significant inequalities in colorectal cancer screening before and during the coronavirus disease 2019 pandemic in Israel, despite a declared policy of equality and universal insurance.

Prevalence of colonoscopy in Japan using a large-scale health claims data compared to esophagogastroduodenoscopy

OBJECTIVE

Prevalence of colonoscopy (CS) is an important countermeasure against colorectal cancer (CRC). In this study, we used large-scale data for a comparison of CS with esophagogastroduodenoscopy (EGD) in Japan.

METHODS

This was a retrospective descriptive study. Commercially anonymized patient data were collected from various health insurance societies (JMDC, Inc. Tokyo, Japan) generated from the insurance registry, receipts (inpatient, outpatient, and prescription), and health checkup data. The data also included healthy subjects who had never been examined in a hospital. The data of 2,760,048 persons who were 50-75 years old during January 2012-December 2019 were extracted from the original data source. The annual rate, the prevalence rate (frequency of those undergoing at least one endoscopy during the period), and the percentage of repeaters (undergoing endoscopy at least twice during the period) of CS were calculated and compared to those of EGD.

RESULTS

The annual rates in 2012/2015/2019 were 3.4%/4.5%/5.3% for CS, respectively, and increased gradually from 2012 to 2019. Those rates were 7.0%/7.9%/7.4% for EGD, respectively, and did not increase. The prevalence rates of CS and EGD were 25.3% and 36.2%, respectively, among the 137,246 participants over 8 years. The prevalence rates of individuals in their 50 s/60 s/70 s were 23.0%/25.9%/31.4% for CS and 33.0%/37.6%/40.7% for EGD, respectively. The proportions of males/females were 27.9%/20.7% for CS, and 36.4%/35.8% for EGD, respectively. The repeat rates of CS and EGD were 40.3% and 44.8%, respectively, over 8 years.

CONCLUSIONS

Using large-scale data, we determined the status of CS and EGD in Japan.

Quantified trends in provider reimbursement and utilization volume in colorectal cancer screenings: analysis of Medicare claims from 2000 to 2019

AIM

Colorectal cancer (CRC) screening rates in the United States remain persistently below guideline targets, partly due to suboptimal patient utilization and provider reimbursement. To guide long-term national utilization estimates and set reasonable screening adherence targets, this study aimed to quantify trends in utilization of and reimbursement for CRC screenings using Medicare claims.

METHOD

Inflation-adjusted reimbursements and utilization volume associated with each CRC screening code were abstracted from Medicare claims between 2000 and 2019. Screenings, screenings/100 000 enrolees and reimbursement/screening were analysed with linear regression and compared with the equality of slopes tests. Average reimbursement per screening was compared using analysis of variance with Dunnett's T3 multiple comparisons test.

RESULTS

The growth rate of multitarget stool DNA tests (mt-sDNA)/100 000 was the highest at 170.4 screenings/year (R2 = 0.99, p ≤ 0.001), while that of faecal occult blood tests/100 000 was the lowest at -446.4 screenings/year (R2 = 0.90, p ≤ 0.001) (p ≤ 0.001). Provider reimbursements averaged $546.95 (95% CI $520.12-$573.78) per mt-sDNA screening, significantly higher than reimbursements for all invasive screenings. Only FOBTs significantly increased in reimbursement per screening at $0.62/year (R2 = 0.91, p ≤ 0.001).

CONCLUSION

We derived forecastable trend numbers for utilization and provider reimbursement. Faecal immunochemical tests/100 000 and mt-sDNA screenings/100 000 increased most rapidly during the entire study period. The number of nearly all invasive screenings/100 000 decreased rapidly; the number of colonoscopies/100 000 increased slightly, probably due to superior diagnostic strength. These trends indicate the that replacement of other invasive modalities with accessible noninvasive screenings will account for much of future screening behaviour and thus reductions in CRC incidence and mortality, especially given providers' reimbursement incentive to screen average-risk patients with stool-based tests.

Design and validation of an artificial intelligence system to detect the quality of colon cleansing before colonoscopy

BACKGROUND AND AIMS

Patients' perception of their bowel cleansing quality may guide rescue cleansing strategies before colonoscopy. The main aim of this study was to train and validate a convolutional neural network (CNN) for classifying rectal effluent during bowel preparation intake as "adequate" or "inadequate" cleansing before colonoscopy.

PATIENTS AND METHODS

Patients referred for outpatient colonoscopy were asked to provide images of their rectal effluent during the bowel preparation process. The images were categorized as adequate or inadequate cleansing based on a predefined 4-picture quality scale. A total of 1203 images were collected from 660 patients. The initial dataset (799 images), was split into a training set (80%) and a validation set (20%). The second dataset (404 images) was used to develop a second test of the CNN accuracy. Afterward, CNN prediction was prospectively compared with the Boston Bowel Preparation Scale (BBPS) in 200 additional patients who provided a picture of their last rectal effluent.

RESULTS

On the initial dataset, a global accuracy of 97.49%, a sensitivity of 98.17% and a specificity of 96.66% were obtained using the CNN model. On the second dataset, an accuracy of 95%, a sensitivity of 99.60% and a specificity of 87.41% were obtained. The results from the CNN model were significantly associated with those from the BBPS (P<0.001), and 77.78% of the patients with poor bowel preparation were correctly classified.

CONCLUSION

The designed CNN is capable of classifying "adequate cleansing" and "inadequate cleansing" images with high accuracy.

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.

Early screening of colorectal cancer using feature engineering with artificial intelligence-enhanced analysis of nanoscale chromatin modifications

Colonoscopy is accurate but inefficient for colorectal cancer (CRC) prevention due to the low (~ 7 to 8%) prevalence of target lesions, advanced adenomas. We leveraged rectal mucosa to identify patients who harbor CRC field carcinogenesis by evaluating chromatin 3D architecture. Supranucleosomal disordered chromatin chains (~ 5 to 20 nm, ~1 kbp) fold into chromatin packing domains (~ 100 to 200 nm, ~ 100 to 1000 kbp). In turn, the fractal-like conformation of DNA within chromatin domains and the folding of the genome into packing domains has been shown to influence multiple facets of gene transcription, including the transcriptional plasticity of cancer cells. We deployed an optical spectroscopic nanosensing technique, chromatin-sensitive partial wave spectroscopic microscopy (csPWS), to evaluate the packing density scaling D of the chromatin chain conformation within packing domains from rectal mucosa in 256 patients with varying degrees of progression to colorectal cancer. We found average packing scaling D of chromatin domains was elevated in tumor cells, histologically normal-appearing cells 4 cm proximal to the tumor, and histologically normal-appearing rectal mucosa compared to cells from control patients (p < 0.001). Nuclear D had a robust correlation with the model of 5-year risk of CRC with r2 = 0.94. Furthermore, rectal D was evaluated as a screening biomarker for patients with advanced adenomas presenting an AUC of 0.85 and 85% sensitivity and specificity. artificial intelligence-enhanced csPWS improved diagnostic performance with AUC = 0.90. Considering the low sensitivity of existing CRC tests, including liquid biopsies, to early-stage cancers our work highlights the potential of chromatin biomarkers of field carcinogenesis in detecting early, significant precancerous colon lesions.

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.

Stool Glycoproteomics Signatures of Pre-Cancerous Lesions and Colorectal Cancer

Colorectal cancer (CRC) screening relies primarily on stool analysis to identify occult blood. However, its sensitivity for detecting precancerous lesions is limited, requiring the development of new tools to improve CRC screening. Carcinogenesis involves significant alterations in mucosal epithelium glycocalyx that decisively contribute to disease progression. Building on this knowledge, we examined patient series comprehending premalignant lesions, colorectal tumors, and healthy controls for the T-antigen-a short-chain O-glycosylation of proteins considered a surrogate marker of malignancy in multiple solid cancers. We found the T-antigen in the secretions of dysplastic lesions as well as in cancer. In CRC, T-antigen expression was associated with the presence of distant metastases. In parallel, we analyzed a broad number of stools from individuals who underwent colonoscopy, which showed high T expressions in high-grade dysplasia and carcinomas. Employing mass spectrometry-based lectin-affinity enrichment, we identified a total of 262 proteins, 67% of which potentially exhibited altered glycosylation patterns associated with cancer and advanced pre-cancerous lesions. Also, we found that the stool (glyco)proteome of pre-cancerous lesions is enriched for protein species involved in key biological processes linked to humoral and innate immune responses. This study offers a thorough analysis of the stool glycoproteome, laying the groundwork for harnessing glycosylation alterations to improve non-invasive cancer detection.

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.).

Unsatisfactory Fecal Immunochemical Tests for Colorectal Cancer Screening: Prevalence, Reasons, and Subsequent Testing

BACKGROUND

Fecal immunochemical test (FIT) is an effective colorectal cancer screening modality. Little is known about prevalence, reasons, and testing after unsatisfactory FIT, or a FIT that cannot be processed by the laboratory due to inadequate stool specimen or incomplete labeling.

METHODS

Our retrospective cohort study examined unsatisfactory FIT among average-risk individuals aged 50-74 years in a large, integrated, safety-net health system who completed an index FIT from 2010 to 2019. We determined prevalence of unsatisfactory FIT and categorized reasons hierarchically. We used multivariable logistic regression models to identify factors associated with: (i) unsatisfactory FIT; and (ii) subsequent testing within 15 months of the unsatisfactory FIT.

RESULTS

Of 56,980 individuals completing an index FIT, 10.2% had an unsatisfactory FIT. Reasons included inadequate specimen (51%), incomplete labeling (27%), old specimen (13%), and broken/leaking container (8%). Unsatisfactory FIT was associated with being male [OR, 1.10; confidence interval (CI), 1.03-1.16], Black (OR, 1.46; CI, 1.33-1.61), Spanish speaking (OR, 1.12; CI, 1.01-1.24), on Medicaid (OR, 1.42; CI, 1.28-1.58), and received FIT by mail (OR, 2.66; CI, 2.35-3.01). Among those with an unsatisfactory FIT, fewer than half (41%) completed a subsequent test within 15 months (median, 4.4 months). Adults aged 50-54 years (OR, 1.16; CI, 1.01-1.39) and those who received FIT by mail (OR, 1.92; CI, 1.49-2.09) were more likely to complete a subsequent test.

CONCLUSIONS

One in ten returned a FIT that could not be processed, mostly due to patient-related reasons. Fewer than half completed a subsequent test after unsatisfactory FIT.

IMPACT

Screening programs should address these breakdowns such as specimen collection and labeling to improve real-world effectiveness. See related In the Spotlight, p. 183.

Fecal Immunochemical Test Screening: Maximizing Success by Minimizing Failure

Implementing fecal immunochemical testing (FIT) through clinic based opportunistic screening or programmatic mailing is not as straightforward as it seems. Liu and colleagues present data for 56,980 individuals who submitted a FIT in a safety net hospital system. In 10.2% (N = 5,819), the test was deemed unsatisfactory. These data demonstrate that there is significant room for improvement in clinical practice regarding colorectal cancer screening with FIT. The high rate of 10% for unsatisfactory FIT tests is higher than the 5% benchmark suggested by the U.S. Multi-Society Task Force on colorectal cancer screening. To maximize FIT success, there needs to be a preoccupation with failure at the system level that results in reducing the number of FIT tests that are rejected. Completing a stool test independently at home is not easy. The medical system needs to help and support individuals in completing the test every step of the way. Suggestions include patient related tips such as labelling and mailing the tests. There are also suggestions for the ordering clinician including administrative tracking to notify clinicians when a FIT has not been performed or is rejected. Papers like this get us focused exactly where we need to be to improve FIT-based screening. See related article by Liu et al., p. 215.

Colorectal Cancer Screening Programs in Latin America: A Systematic Review and Meta-Analysis

Importance

Colorectal cancer (CRC) is a leading cause of cancer-related mortality globally, with increasing incidence and mortality in Latin America. CRC screening programs can reduce disease burden, but information on screening programs in Latin America is limited.

Objective

To describe characteristics (eg, type of program, uptake, neoplastic yield) of CRC screening programs in Latin America.

Data Sources

PubMed, Ovid MEDLINE, EMBASE, Cochrane, PsycINFO, Web of Science Core Collection, LILACS, and SciELO were searched from inception to February 2023. Relevant references from bibliographies, conference proceedings, and gray literature were considered. The search strategy included English, Spanish, and Portuguese terms.

Study Selection

Included were studies of CRC screening programs in Latin America using fecal immunochemical test (FIT) or colonoscopy as the primary screening method. Four reviewers independently assessed study eligibility based on titles, with review of abstracts and full texts as needed.

Data Extraction and Synthesis

Guidelines from Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were followed for data abstraction and quality assessment. Descriptive information was extracted, and data were pooled using a random-effects model.

Main outcomes and Measures

Program performance indicators included rates of participation and FIT positivity, adenoma detection rate (ADR), advanced adenoma detection rate (AADR), CRC detection rate, and colonoscopy quality indicators.

Results

There were 17 studies included from upper middle-income and high-income countries in Latin America with a total of 123 929 participants. Thirteen studies used FIT as the initial screening method, whereas 4 used screening colonoscopy. The participation rate in FIT-based programs was 85.8% (95% CI, 78.5%-91.4%). FIT positivity rates were 15.2% (95% CI, 9.6%-21.8%) for the 50-ng/mL threshold and 9.7% (95% CI, 6.8%-13.0%) for the 100-ng/mL threshold. For FIT-based studies, the pooled ADR was 39.0% (95% CI, 29.3%-49.2%) and CRC detection rate was 4.9% (95% CI, 2.6%-7.9%); for screening colonoscopy-based studies, the pooled ADR was 19.9% (95% CI, 15.5%-24.8%) and CRC detection rate was 0.4% (95% CI, 0.1%-0.8%).

Conclusions and Relevance

This systematic review and meta-analysis suggests that CRC screening in upper middle-income countries in Latin America is feasible, detecting rates of neoplasia comparable with those of high-income regions. Population-based screening programs should be developed or enhanced in these settings. There is a knowledge gap regarding feasibility and yield of screening programs in lower middle-income countries.

Uncovering a dose-response relationship between positive fecal immunochemical test (FIT) and all-cause, cardiovascular and cancer-related mortality

BACKGROUND

Fecal immunochemical test (FIT) is for colorectal cancer (CRC) screening. Its association with non-CRC mortality has been overlooked. Given the quantitative FIT values, its dose-response relationships with different causes of deaths and years of life shortened were assessed.

METHODS

This retrospective study included 546,214 adults aged ≥ 20 who attended a health surveillance program from 1994 to 2017 and were followed up until the end of 2020. FIT ≥ 20 μg Hb/g was defined as positive. The Cox model was used to assess adjusted hazard ratios (aHR).

RESULTS

Positive FIT was associated with increased all-cause mortality (aHR: 1.34, 95 % CI: 1.25-1.44) and all-cancer mortality (aHR: 1.71, 95 % CI: 1.55-1.89), with a reduction of life expectancy by 4 years. The association remained even with CRC excluded. With each 10 μg Hb/g increase in FIT above 20 μg Hb/g, life expectancy was reduced by one year, and mortality increased by 4 %. About 18.6 % of deaths with positive FIT were attributed to cardiovascular disease (CVD), followed by CRC (13.5 %) and upper gastrointestinal (GI) cancers (4.5 %). The all-cause mortality rate after excluding CRC for positive FIT was 3.56/1,000 person-year, comparable to the all-cause mortality rate of 3.69/1,000 person-year for hypertension.

CONCLUSION

Positive FIT was associated with increased mortality in a dose-response manner and shortened life expectancy by 4 years, an overlooked risk comparable to hypertension, even with CRC excluded. After a negative colonoscopy, subjects with positive FIT should undergo a workup on CVD risk factors and look for other upper GI cancers.

Estimate of Increase in Colorectal Cancer Diagnoses with Expansion of Fecal Immunochemical Testing in an Urban Safety-Net Population

BACKGROUND

Fecal immunochemical test (FIT) is less effective in detecting advanced adenomas (AA) than colonoscopy. Increase in FIT for colorectal cancer (CRC) screening may lead to an increased number of undetected AAs which may develop into future CRCs.

AIM

We determined the potential impact of FIT expansion on missed AAs and future CRC diagnoses in an urban, tertiary-care, safety-net hospital.

METHODS

CRC and AA diagnoses were identified in patients undergoing colonoscopy for average-risk CRC screening or positive FIT between 2017 and 2019 at Boston Medical Center. Poisson regression modeling was used to estimate the frequency of AAs per year by age group using data from 2017 to 2019, assuming average outpatient volume and proportion of screening colonoscopies. Total number of patients who received FIT was extrapolated from those who underwent colonoscopy for positive FIT. We estimated AAs per year if 'one-time' FIT was used for screening in 75% and 100% of the population and subtracted this from the estimated AAs per year under the Poisson model to determine missed AAs. We used previously described, age and gender specific estimates of the annual progression of AA to CRC.

RESULTS

The estimated number of CRCs detected per year is 4.6/1785 males and 4.6/2086 females screened. With 75% FIT expansion, we estimate an additional 3.5 (95% CI 1.3, 9.5) and 2.2 (95% CI 0.64, 7.6) CRCs; with 100% FIT expansion, we estimate an additional 7.4 (95% CI 3.7, 14.9) and 4.2 (95% CI 1.7, 10.5) CRCs, in 5 years, in males and females, respectively.

CONCLUSION

Expansion of FIT may substantially increase CRC incidence.

Post-colonoscopy colorectal cancer: A population-based cohort study of fecal occult blood test-positive colonoscopies

BACKGROUND

Data on post-colonoscopy colorectal cancers (PCCRCs) after fecal occult blood test (FOBT)-positive colonoscopies is scarce (guaiac-based (gFOBT) or fecal immunochemical test (FIT)).

AIMS

Evaluate the prevalence and characteristics of PCCRCs in the French gFOBT CRC screening program.

METHODS

Retrospective population-based cohort study of all gFOBT-positive colonoscopies performed among individuals aged 50-74 between 2003 and 2014 within the CRC screening program organized in the Haut-Rhin (Alsace, France). The main outcome was PCCRC-3y rate. Adenoma detection rates (ADRs) calculated on gFOBT-positive colonoscopies were compared to those calculated on FIT-positive colonoscopies performed by the same gastroenterologists.

RESULTS

Overall, 9106 gFOBT-positive colonoscopies performed by 36 gastroenterologists were included. Sixteen PCCRC-3y and 31 PCCRC-5y were diagnosed (68.8 % and 58.1 % were true interval PCCRCs respectively). The unadjusted PCCRC-3y rate was 2.4 % [95 % confidence interval (CI) 1.4 %-3.9 %]. The risk for PCCRC-5y was significantly higher when the gastroenterologist's ADR was <35 % compared to ≥35 % (HR 2.17 [95 %CI 1.19-3.93]). The mean absolute difference for ADR between gFOBT- and FIT-positive colonoscopies was 16.3 % in favor of FIT-positive colonoscopies.

CONCLUSION

PCCRC-3y prevalence was low, estimated at 2.4 %. We suggest that the minimum standard for ADR in gFOBT- and FIT-positive colonoscopies should be set at 35 % and 50 % to 55 % respectively, in the French screening program.

Why is early detection of colon cancer still not possible in 2023?

Colorectal cancer (CRC) screening is a fundamental tool in the prevention and early detection of one of the most prevalent and lethal cancers. Over the years, screening, particularly in those settings where it is well organized, has succeeded in reducing the incidence of colon and rectal cancer and improving the prognosis related to them. Despite considerable advancements in screening technologies and strategies, the effectiveness of CRC screening programs remains less than optimal. This paper examined the multifaceted reasons behind the persistent lack of effectiveness in CRC screening initiatives. Through a critical analysis of current methodologies, technological limitations, patient-related factors, and systemic challenges, we elucidated the complex interplay that hampers the successful reduction of CRC morbidity and mortality rates. While acknowledging the advancements that have improved aspects of screening, we emphasized the necessity of addressing the identified barriers comprehensively. This study aimed to raise awareness of how important CRC screening is in reducing costs for this disease. Screening and early diagnosis are not only important in improving the prognosis of patients with CRC but can lead to an important reduction in the cost of treating a disease that is often diagnosed at an advanced stage. Spending more sooner can mean saving money later.

Comparative Study of Predictive Models for the Detection of Patients at High Risk of Inadequate Colonic Cleansing

Background: Various predictive models have been published to identify outpatients with inadequate colonic cleansing who may benefit from intensified preparations to improve colonoscopy quality. The main objective of this study was to compare the accuracy of three predictive models for identifying poor bowel preparation in outpatients undergoing colonoscopy. Methods: This cross-sectional study included patients scheduled for outpatient colonoscopy over a 3-month period. We evaluated and compared three predictive models (Models 1-3). The quality of colonic cleansing was assessed using the Boston Bowel Preparation Scale. We calculated the area under the curve (AUC) and the corresponding 95% confidence interval for each model. Additionally, we performed simple and multiple logistic regression analyses to identify variables associated with inadequate colonic cleansing and developed a new model. Results: A total of 649 consecutive patients were included in the study, of whom 84.3% had adequate colonic cleansing quality. The AUCs of Model 1 (AUC = 0.67, 95% CI [0.63-0.70]) and Model 2 (AUC = 0.62, 95% CI [0.58-0.66]) were significantly higher than that of Model 3 (AUC = 0.54, 95% CI [0.50-0.58]; p < 0.001). Moreover, Model 1 outperformed Model 2 (p = 0.013). However, the new model did not demonstrate improved accuracy compared to the older models (AUC = 0.671). Conclusions: Among the three compared models, Model 1 showed the highest accuracy for predicting poor bowel preparation in outpatients undergoing colonoscopy and could be useful in clinical practice to decrease the percentage of inadequately prepared patients.

Adenoma location, size, and morphology are risk factors for FOBT false-negative results in inpatients with advanced colorectal adenoma

Recently, advanced adenoma (AA) has been recognized as a target for colorectal cancer (CRC) screening. However, the fecal occult blood test (FOBT), the primary non-invasive screening method, shows limited sensitivity in detecting AA. This study investigates the relationship between adenoma characteristics and FOBT false-negative results. In a retrospective cohort study conducted from 2015 to 2022, we examined 342 inpatients with AA who underwent colonoscopy and received qualitative FOBT. FOBT sensitivity was analyzed about various adenoma characteristics, and logistic regression models were employed to investigate the relationship between adenoma features and FOBT false-negative outcomes. FOBT sensitivity in AA inpatients was 52.63%. Significant differences in sensitivity were observed based on adenoma location (left vs. right), morphology (with or without pedunculation), and size (≤ 10 mm vs. > 10 mm). After adjusting for several potential confounders, FOBT showed a reduced false-negative rate in AA with large-sized (OR, 0.49; 95% CI 0.31-0.77), left-sided location (OR, 0.53; 95% CI 0.31-0.89), and pedunculated morphology (OR, 0.73; 95% CI 0.43-1.24). AA with large size, left-sided location, and pedunculated morphology independently contribute to a decreased rate of FOBT false-negative results. However, these adenoma characteristics are not actively modifiable. Therefore, novel non-invasive methods are needed to improve AA detection accuracy.

Examining the Sustainability of Core Capacity and Evidence-Based Interventions for FIT-Based CRC Screening: California Colorectal Cancer Control Program

OBJECTIVES

We examined the extent to which funded satellite clinics could sustain the California Colon Cancer Control Program (C4P) strategies implemented in health systems to increase uptake of the fecal immunochemical test (FIT) or immunochemical fecal occult blood test (iFOBT) for colorectal cancer (CRC) screening in the absence of future C4P funds.

INTRODUCTION

Seven health systems consisting of 38 satellite clinics participated in C4P to examine the sustainability of the program in the absence future Centers for Disease Control and Prevention (CDC) funding.

METHODS

Quantitative and qualitative methods with a close and open-ended survey approach, and a prospective cohort design were used to examine the sustainability of the C4P in health systems.

RESULTS

A total of 61% of satellite clinics could not sustain funding stability. Only 26% could sustain funding stability. About, 71%, 26%, and 21% of the satellite clinics could sustain the small media platform, patient navigation services, and community health workers (CHWs), respectively. All the satellite clinics sustained the provider reminder system and professional development. Roughly, 71% and 42% of funded satellite clinics could not sustain the patient navigators and CHWs, respectively. The satellite clinics that could sustain funding stability, sustained patient navigation services and CHWs. Health systems that could not sustain funding stability, could not sustain patient navigation services and CHWs. Qualitatively, the need to support uninsured priority populations, health educators, patient navigators, care coordination activities, outreach services, and provision of enhanced services emerged. The need to support enhanced quality measures, expansion of funding, Medi-Cal Public Hospital Redesign and Incentive coverage, health plan, community linkages, resource sharing, and best practices specifically on CRC screening emerged. Themes such as automated reminder, limited personalized care delivery and capacity, transportation barriers, staff salary, expansion of care through patient navigation, and culturally appropriate media campaign also emerged.

CONCLUSION

Overall, to address sustainability barriers, funding stability should be maintained in the health systems.

Fecal Occult Blood Screening before Cardiac Surgery

BACKGROUND

Concerns of gastrointestinal (GI) bleeding after cardiac surgery are increasing with increased use of antiplatelets and anticoagulants. We investigated the roles of preoperative screening for fecal occult blood by fecal immunochemical test (FIT) widely used to detect GI bleeding and cancer.

METHODS

A retrospective review was done in 1,663 consecutive patients undergoing FIT before cardiac surgery between years 2012 and 2020. One or two rounds of FIT were performed 2 to 3 weeks before surgery, when antiplatelets and anticoagulants were not suspended yet.

RESULTS

Positive FIT (> 30 μg of hemoglobin/g of feces) was observed in 227 patients (13.7%). Preoperative risk factors for positive FIT included age > 70 years, anticoagulants, and chronic kidney disease. Of those with positive FIT, 180 patients (79%) received preoperative endoscopy, including gastroscopy (n = 139), colonoscopy (n = 9), and both (n = 32), with no findings of bleeding. The most common finding of gastroscopy was atrophic gastritis (36%) while early gastric cancer was detected in 2 patients. The most common finding of colonoscopy was colon polyps (42%) while colorectal cancer was detected in 5 patients. Of 180 FIT-positive patients receiving endoscopy, 8 (4.4%) underwent preoperative GI treatment, while postoperative GI events were documented in 28 (15.6%). Of 1,436 with negative FIT, 21 (1.5%) presented GI complications after surgery.

CONCLUSION

Preoperative FIT, which is influenced by anticoagulant use, has little impacts on identification of GI bleeding sites. However, it may be useful to detect GI malignant lesions, potentially impacting operative risks, surgical strategies, and postoperative management.