Colorectal Cancer Screening: Recommendations for Physicians and Patients From the U.S. Multi-Society Task Force on Colorectal Cancer

Comparison of some biochemical markers between early‐onset and late‐onset colorectal precancerous lesions: A single‐center retrospective study

Objective

Given that the onset of diseases including colorectal cancer precursors is affecting younger individuals and that obesity is an important risk factor for early‐onset, we conducted a study to explore the biochemical profile of differences in serum between early‐onset patients and late‐onset colorectal precancerous lesions.

Methods

A total of 1447 patients, including 469 early‐onset patients and 978 late‐onset patients, were enrolled from the First Affiliated Hospital of Nanchang University (FAHNU), of which there were 311 sessile serrated adenoma/polyps (SSA/P) and 1136 normal adenomas. The distribution of the included categorical variables was compared via Pearson's chi‐squared test, whereas continuous variables were compared by using the nonparametric Kruskal–Wallis test and anova.

Results

Compared with late‐onset patients, the levels of total bilirubin and HDL‐C were lower (p < 0.05), whereas triglyceride and uric acid levels were higher, in early‐onset patients. Interestingly, in the subgroup analysis, triglyceride and uric acid levels remained at higher levels, whereas HDL‐C remained at lower levels, in early‐onset patients than in late‐onset patients. Other characteristics, such as LDL‐C, drinking, γ‐GT, and the N/L ratio, were similar between the two groups. An additional analysis of the association of tumor size with markers showed that lower levels of HDL‐C and higher levels of uric acid were associated with increased tumor size (p < 0.05).

Conclusions

Early‐onset CRC precursor cases exhibit higher levels of triglycerides and lower levels of HDL‐C than late‐onset cases. Additionally, levels of HDL‐C are negatively associated with tumor size, whereas uric acid was positively correlated with tumor size.

Colorectal Cancer Screening Program in Songjiang district, Shanghai between 2015 and 2017: Evaluation of participation rate and the associated factor

Little is known about the participation rate of newly implemented colorectal cancer (CRC) screening programs in China. Our goals were to identify factors associated with nonparticipation for CRC screening in Songjiang District, Shanghai. We analyzed individuals included in an observational cohort study from 4 towns (Xin Qiao, She Shan, Mao Gang, and Zhong Shan) in Songjiang District. The participation rate was calculated for the CRC screening program based on a fecal immunochemical test and a risk assessment questionnaire between 2015 and 2017 inclusive. Of the 27,130 individuals eligible for inclusion in this study, 20,863 (76.9%) participated in CRC screening at least once during 2015 and 2017. The factors linked with nonparticipation were; being male (odds ratio [OR] 0.87, 95% confidence interval [CI] 0.82-0.93, P < .01), unmarried (OR 0.71, 95% CI 0.64-0.80, P < .01), having a high education level (middle school, OR 0.82, 95% CI 0.74-0.90, P < .01, high school or above, OR 0.64, 95% CI 0.57-0.73, P < .01), absence of chronic disease (OR 0.90, 95% CI 0.85-0.96, P < .01), and living in 2 out of the 4 towns covered (Xin Qiao, OR 0.72, 95% CI 0.66-0.78, P < .01, Zhong Shan, OR 0.29, 95% CI 0.26-0.31, P < .01). The current study revealed several associated factors with nonparticipation for the CRC screening in Songjiang district. These findings will help identify target populations that require an individualized approach to increase the participation rate.

What Constitutes Evidence? Colorectal Cancer Screening and the U.S. Preventive Services Task Force

The United States Preventive Services Task Force is perhaps America's best-known source of evidence-based medicine (EBM) recommendations. This paper reviews aspects of the history of one such recommendation-screening for colorectal cancer (CRC)-to explore how the Task Force evaluates the best available evidence to reach its conclusions.Although the Task Force initially believed there was inadequate evidence to recommend CRC screening in the 1980s, it later changed its mind. Indeed, by 2002, it was recommending screening colonoscopy for those aged 50 and older, "extrapolating" from the existing evidence as there were no randomized controlled trials of the procedure. By 2016, due in part to the use of an emerging analytic modality known as modeling, the Task Force supported four additional CRC screening tests that lacked randomized data. Among the reasons the Task Force gave for these decisions was the desire to improve adherence for a strategy-screening healthy, asymptomatic individuals-that it believed saved lives.During these same years, the Task Force diverged from other organizations by declining to advocate screening otherwise healthy Black patients earlier than age 50-despite the fact that such individuals had higher rates of CRC than the general population, higher mortality from the disease and earlier onset of the disease. In declining to extrapolate in this instance, the Task Force underscored the lack of reliable data that proved that the benefits of such testing would outweigh the harms.The history of CRC screening reminds us that scientific evaluation relies not only on methodological sophistication but also on a combination of intellectual, cognitive and social processes. General internists-and their patients-should realize that EBM recommendations are often not definitive but rather thoughtful data-based advice.

Virtual Non-contrast Imaging in The Abdomen and The Pelvis: An Overview

Virtual non-contrast (VNC) imaging is a post-processing technique generated from contrast-enhanced scans using dual-energy computed tomography (DECT). It is generated by removing iodine from imaging acquired at multiple energies. Myriad clinical studies have shown its ability to diagnose the various abdominal and pelvic pathologies discussed in the article. VNC is also a problem-solving tool for characterizing incidentally detected lesions ("incidentalomas"), often decreasing the need for additional follow-up imaging. It also obviates the multiphase image acquisitions to evaluate hematuria, hepatic steatosis, aortic endoleaks, and gastrointestinal bleeding by generating image datasets from different tissue attenuation values. The scope of this article is to provide an overview of various applications of VNC imaging obtained by DECT in the abdomen and pelvis.

Normal Gastrointestinal Mucosa at Biopsy and Overall Mortality: Nationwide Population-Based Cohort Study

Background

Normal gastrointestinal (GI) mucosa on endoscopy has been linked to a lower risk of colorectal cancer (CRC) but its association to overall death is unknown.

Methods

We identified 466,987 individuals with a first GI biopsy 1965–2016 with normal mucosa (60.6% upper GI and 39.4% lower GI) through all Swedish pathology departments (n = 28). They were individually matched to 2,321,217 reference individuals without a GI biopsy and also compared to 505,076 full siblings. Flexible parametric models were applied to estimate hazard ratio (HRs) and 95% confidence interval (95% CI) for death.

Results

During a median follow-up of ~11 years, 85,859 (18.39%) of individuals with normal mucosa and 377,653 (16.27%) of reference individuals died. This corresponded to incidence rates of 147.56/10,000 vs 127.90/10,000 person-years respectively (rate difference: 19.66/10,000 person-years), with the multivariable-adjusted HR of 1.21 (95% CI: 1.20–1.22). Excess mortality was seen for both upper and lower biopsy with normal mucosa. Particularly higher HRs for death were seen in males, individuals biopsied when aged <40 years, those without a prior record of GI disease, and those with high education. Mortality risk was most increased in the first five years after biopsy (HR = 1.34; 95% CI: 1.32–1.36) but decreased thereafter. Having a GI biopsy with normal mucosa was associated with excess mortality from cardiovascular (CVD)disease (HR = 1.02; 95% CI: 1.01–1.03), cancer (HR = 1.58; 95% CI: 1.56–1.61), GI disease (HR = 1.65; 95% CI: 1.58–1.71), and other causes (HR = 1.10; 95% CI: 1.08–1.11). Sibling comparisons yielded similar results.

Conclusion

Compared with individuals without a GI biopsy, those with a normal GI biopsy due to clinical symptoms had a higher mortality particularly in the first five years after biopsy, and especially from GI disease and cancer.

Network Pharmacology and Molecular Docking on the Molecular Mechanism of Jiawei-Huang Lian-Gan Jiang Decoction in the Treatment of Colorectal Adenomas

Purpose

Jiawei-Huang Lian-Gan Jiang decoction (JWHLGJD) was developed to treat and prevent the patients with colorectal adenomas (CRA) in China. This study is aimed to discover JWHLGJD's active compounds and demonstrate mechanisms of JWHLGJD against CRA through network pharmacology and molecular docking techniques.

Methods

All the components of JWHLGJD were retrieved from the pharmacology database of Traditional Chinese Medicine Systems Pharmacology (TCMSP). The GeneCards database, the Online Mendelian Inheritance in Man database (OMIM), the DrugBank database, and PharmGKB were used to obtain the genes matching the targets. Cytoscape created the compound-target network. The network of target protein-protein interactions (PPI) was constructed using the STRING database. Gene Ontology (GO) functional and the Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathways involved in the targets were analyzed by using the DAVID database. Cytoscape created the component-target-pathway (C-T-P) network. AutoDock Vina software was used to verify the molecular docking of JWHLGJD components and key targets. Core genes linked with survival and tumor microenvironment were analyzed through the Kaplan–Meier plotter and TIMER 2.0 databases, respectively.

Results

Compound-target network mainly contained 38 compounds and 130 targets of the JWHLGJD associated with CRA. TP53, MAPK1, JUN, HSP90AA1, and AKT1 were identified as core targets by the PPI network. KEGG pathway shows that the pathways in cancer, lipids, and atherosclerosis, PI3K-Akt signaling pathway and MAPK signaling pathway, are the most relevant pathways to CRA. The C-T-P network suggests that the active component in JWHLGJD is capable of regulating target genes of these related pathways. The results of molecular docking showed that berberine and stigmasterol were the top two compounds of JWHLGJD, which had high affinity with TP53 and MAPK1, respectively. And, MAPK1 exerted a more significant effect on the prognosis of adenocarcinoma, for it was highly associated with various immune cells.

Conclusion

Findings in this study provided light on JWHLGJD's active components, prospective targets, and molecular mechanism. It also gave a potential way to uncovering the scientific underpinning and therapeutic mechanism of traditional Chinese medicine (TCM) formulas.

Commencing colorectal cancer screening at age 45 years in U.S. racial groups

Screening for colorectal cancer (CRC) is cost-effective for reducing its mortality among the average-risk population. In the US, CRC incidence and mortality differ among racial/ethnic groups, with non-Hispanic Blacks (NHB) and American Indian/Alaska Natives showing highest incidence and mortality and earlier presentation. Since 2005, some professional societies have recommended CRC screening for NHB to commence at 45 years or earlier; this was not implemented due to lack of recommendation from key groups that influence insurance payment coverage. In 2017 the highly influential U.S. Multi-Society Task Force for Colorectal Cancer recommended screening to commence at 45 years for NHB; this recommendation was supplanted by data showing an increase in early-onset CRCs in non-Hispanic Whites approaching the under-50-year rates observed for NHB. Subsequently the American Cancer Society and the USPSTF recommended that the entire average-risk population move to commence CRC screening at 45 years. Implementing screening in 45–49-year-olds has its challenges as younger groups compared with older groups participate less in preventive care. The US had made extensive progress pre-COVID-19 in closing the disparity gap for CRC screening in NHB above age 50 years; implementing screening at younger ages will take ingenuity, foresight, and creative strategy to reach a broader-aged population while preventing widening the screening disparity gap. Approaches such as navigation for non-invasive and minimally invasive CRC screening tests, removal of financial barriers such as co-pays, and complete follow up to abnormal non-invasive screening tests will need to become the norm for broad implementation and success across all racial/ethnic groups.

Noninvasive early detection of colorectal cancer by hypermethylation of the LINC00473 promoter in plasma cell-free DNA

BACKGROUND

Current noninvasive assays have limitations in the early detection of colorectal cancer. We evaluated the clinical utility of promoter methylation of the long noncoding RNA LINC00473 as a noninvasive biomarker to detect colorectal cancer and associated precancerous lesions.

METHODS

We evaluated the epigenetic regulation of LINC00473 through promoter hypermethylation in colorectal cancer cell lines using bisulfite genomic sequencing and expression analyses. DNA methylation of LINC00473 was analyzed in primary colorectal tumors using 450K arrays and RNA-seq from The Cancer Genome Atlas (TCGA). Tissue-based findings were validated in several independent cohorts of colorectal cancer and advanced colorectal polyp patients by pyrosequencing. We explored the clinical utility of LINC00473 methylation for the early detection of colorectal cancer in plasma cell-free DNA by quantitative methylation-specific PCR and droplet digital PCR.

RESULTS

LINC00473 showed transcriptionally silencing due to promoter hypermethylation in colorectal cancer cell lines and primary tumors. Methylation of the LINC00473 promoter accurately detected primary colorectal tumors in two independent clinical cohorts, with areas under the receiver operating characteristic curves (AUCs) of 0.94 and 0.89. This biomarker also identified advanced colorectal polyps from two other tissue-based clinical cohorts with high diagnostic accuracy (AUCs of 0.99 and 0.78). Finally, methylation analysis of the LINC00473 promoter in plasma cell-free DNA accurately identified patients with colorectal cancer and advanced colorectal polyps (AUCs of 0.88 and 0.84, respectively), which was confirmed in an independent cohort of patients.

CONCLUSIONS

Hypermethylation of the LINC00473 promoter is a new promising biomarker for noninvasive early detection of colorectal cancer and related precancerous lesions.

A positive faecal immunochemical test result and its association with the incidence of rheumatoid arthritis, systemic lupus erythematosus, and psoriatic arthritis: an analysis of one-million national colorectal cancer screening programme results

BACKGROUND

Accumulating evidence now indicates that the presence of faecal haemoglobin, in the absence of gastrointestinal bleeding, may be an indicator of systemic inflammation and is linked to the development of human diseases. We evaluated whether a positive faecal immunochemical test (FIT) is associated with the development of immune-mediated inflammatory diseases (IMIDs).

METHODS

Data from the nationwide colorectal cancer screening programme from 2009 to 2013 were used. Participants (n=8,646,887) were divided into FIT (+) and FIT (-) groups by performing a 1:1 random sampling matched by age and sex. Participants with concurrent haemorrhoids, colorectal cancer (CRC), inflammatory bowel disease (IBD), and missed CRC and IBD were excluded using the colonoscopy results, ICD-10 codes, and the special exemption code (V code). Endpoints were the incidence of IMIDs (rheumatoid arthritis [RA], systemic lupus erythematosus [SLE], and psoriatic arthritis [PsA]) after FIT.

RESULTS

Of the 1,044,955 eligible participants, 229,594 and 815,361 individuals were included in the FIT (+) and the FIT (-) groups, respectively. During the mean follow-up period of 7.59 years, a total of 7645 (incidence rate [IR] 9.56/10,000 person-years [PY]), 208 (IR 0.26/10,000 PY), and 101 (IR 0.13/10,000 PY) patients were diagnosed with RA, SLE, and PsA, respectively. An adjusted Cox analysis demonstrated that FIT positivity conferred a 1.16 (95% confidence interval [CI] 1.09-1.24, p<0.001) times greater risk of developing RA. Kaplan-Meier analysis in the 1:2 propensity-score matched population also confirmed these results (hazard ratio [HR] 1.18, 95% CI 1.10-1.27, p<0.001).

CONCLUSIONS

Positive FIT is associated with increased risk of RA in the general population, corroborating that aberrancies of gut mucosa are associated with the development of IMIDs. Vigilant monitoring and early referral to a specialist upon medical suspicion is required in this population.

TRIAL REGISTRATION

Retrospectively registered.

Awareness and Knowledge of Colorectal Cancer Screening Among Medical Students at the University of Aleppo: A Cross-Sectional Study

Background  Colorectal cancer (CRC) is the third leading cause of malignancy in Syria. The aim of our study was to assess the awareness and knowledge of CRC and its screening methods among medical students at the University of Aleppo.

Methods  A cross-sectional study of medical students at the University of Aleppo was conducted using a self-administered 12-element questionnaire. The questionnaire consisted of demographics, awareness of CRC, knowledge of CRC and its screening methods. Awareness of CRC included three questions asking students if they ever heard of CRC and its screening methods. Knowledge of CRC was evaluated through three sets of questions about CRC risk factors, signs and symptoms, and preventative methods. The students were selected randomly during academic lectures. A χ² or Fisher's exact tests for categorical variables were used for statistical analysis, as appropriate. A two-sided p  < 0.05 was considered statistically significant. We stratified students based on pre-clinical versus clinical years and average academic score.

Results  A total of 824 students completed the questionnaire. The majority of students were aware of CRC (98.9%) and CRC screening methods (79.8%). Students had poor knowledge of CRC risk factors (16.5% for non-modifiable factors and 11.7% for modifiable factors), signs and symptoms (52.6%), and protective factors (9.9%). Only 31.7% of students were able to identify the appropriate age to initiate screening for average-risk individuals. Clinical students had better awareness and knowledge of CRC and its screening methods. Clinical students with higher academic score showed better awareness and knowledge in some elements.

Conclusion  Our study reported high awareness and poor knowledge rates of CRC and its screening methods among medical students at the University of Aleppo. Although clinical students had higher awareness and knowledge of CRC compared to pre-clinical students, the impact of academic score revealed variable results.

Changes in Cancer Screening Rates Following a New Cancer Diagnosis in a Primary Care Patient Panel

IMPORTANCE

Although screenings for breast and colorectal cancer are widely recommended, patient screening rates vary greatly and remain below public health targets, and primary care physicians' (PCPs') counseling and referrals play critical roles in patients' use of cancer screenings. Recent adverse events may influence PCPs' decision-making, but it remains unknown whether cancer screening rates of PCPs' patients change after PCPs are exposed to new cancer diagnoses.

OBJECTIVE

To investigate whether PCPs' exposures to patients with new diagnoses of breast or colorectal cancer were associated with changes in screening rates for other patients subsequently visiting the affected PCPs.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used stacked difference-in-differences analyses of all-payer claims data for New Hampshire and Maine in 2009 to 2015. Participants were PCPs caring for patients. Data analysis was performed from June 2020 to May 2022.

EXPOSURES

New diagnosis of a PCP's patient with breast cancer or colorectal cancer.

MAIN OUTCOMES AND MEASURES

Patients' breast and colorectal cancer screening rates within 1 year of a PCP visit.

RESULTS

The sample included 3158 PCPs (1819 male PCPs [57.6%]) caring for 1 920 189 patients (1 073 408 female patients [55.9%]; mean [SD] age, 41.0 [21.9] years) aged 18 to 64 years. During the study period, 898 PCPs had a patient with a new diagnosis of breast cancer and 370 PCPs had a patient with a new diagnosis of colorectal cancer. In the preexposure period, 68 837 female patients (37.3% of those visiting a PCP) underwent breast cancer screening within 1 year of the visit, and 13 137 patients (10.1% of those visiting a PCP) underwent colorectal cancer screening within 1 year of the visit. For both cancer types, after exposure to a new cancer diagnosis, PCPs' cancer screening rates displayed a rapid, sustained increase. Breast cancer screening rates increased by 4.5 percentage points (95% CI, 3.0-6.1 percentage points; P < .001). Colorectal cancer screening rates increased by 1.3 percentage points (95% CI, 0.3-2.2 percentage points; P = .01). Observed breast cancer screening increases were higher for male PCPs than for female PCPs (3.1 percentage points; 95% CI, 0.4-5.8 percentage points; P = .03).

CONCLUSIONS AND RELEVANCE

This study found significant, sustained increases in cancer screening rates for patients visiting PCPs recently exposed to new breast and colorectal cancer diagnoses. These findings suggest that PCPs may update practice patterns on the basis of recent patient diagnoses. Future work should assess whether salient cues to PCPs about patient diagnoses when clinically appropriate can improve screening practices.

Understanding the Burden of Colorectal Adenomas in Patients Younger Than 50 Years: A Large Single-Center Retrospective Cohort Study

BACKGROUND

Colorectal cancer is increasing in young adults. Our understanding of the adenoma-carcinoma sequence in young patients aged <50 years is lacking. The yield obtained by lowering the age of screening colonoscopy remains unclear.

OBJECTIVE

The goal of this study was to understand the burden and histology of colorectal polyps in young adults and to explore predictors of adenoma detection in this population.

DESIGN

This is a retrospective cohort study.

SETTING

Colonoscopies were performed at a single university-affiliated tertiary care center.

PATIENTS

This study included adults aged <50 years who underwent a colonoscopy between 2014 and 2019. Patients with inflammatory bowel disease and genetic disorders were excluded.

MAIN OUTCOME MEASURES

Adenoma detection rates were analyzed according to age. Predictors of adenoma detection were investigated by multiple logistic regression.

RESULTS

A total of 4475 patients were analyzed. The mean age was 40.2 ± 8.0 years, 56.4% were female, and the mean BMI was 26.3 ± 5.5 kg/m2. A family history of colorectal cancer was reported in 23.8% of patients. The overall polyp and adenoma detection rates were 22% and 14%. The majority of polyps were adenomatous (58.9% of all polypectomies) and located in the left colon or rectum (61.4%). The detection rates of adenomas, advanced neoplasias, and adenocarcinomas were highest in patients aged 45 to 49 (19.3%, 4.8%, and 1.3%). On multivariate analysis, variables independently associated with adenoma detection included age (OR 1.08, 95% CI, 1.06-1.1), female sex (OR 1.80, 95% CI, 1.44-2.27), BMI (OR 1.01, 95% CI, 1.01-1.05), and having undergone a diagnostic colonoscopy (OR 1.81, 95% CI, 1.44-2.29). On subgroup analysis of patients aged 45 to 49, the same variables remained associated with adenoma detection except for age.

LIMITATIONS

The study was limited due to the retrospective nature with heterogenous data.

CONCLUSIONS

Adenoma detection in young adults aged 45 to 49 approaches the current adenoma detection of older adults. Predictors of adenoma detection in these young adults are female gender and BMI, which may help guide colorectal cancer screening guidelines in the future. See Video Abstract at http://links.lww.com/DCR/B843.

COMPRENDER DE LA CARGA DE LOS ADENOMAS COLORRECTALES EN PACIENTES AOS UN ESTUDIO DE COHORTE RETROSPECTIVO DE UN SOLO CENTRO

ANTECEDENTES:El cáncer colorrectal está aumentando en adultos jóvenes. No se conoce la secuencia adenoma-carcinoma en pacientes jóvenes <50 años. El rendimiento obtenido al reducir la edad de la colonoscopia de detección sigue sin estar claro.OBJETIVO:Comprender la carga y la histología de los pólipos colorrectales en adultos jóvenes y explorar los predictores de detección de adenomas en esta población.DISEÑO:Estudio de cohorte retrospectivo.AJUSTE:Las colonoscopias se realizaron en un único centro de atención terciario afiliado a la universidad.PACIENTES:Adultos jóvenes <50 años que se sometieron a una colonoscopia entre 2014-2019. Se excluyeron los pacientes con enfermedad inflamatoria intestinal y trastornos genéticos.PRINCIPALES MEDIDAS DE RESULTADO:Se analizaron las tasas de detección de adenomas según la edad. Los predictores de la detección de adenomas se investigaron mediante regresión logística múltiple.RESULTADOS:Se analizaron 4475 pacientes. La edad media fue de 40,2 ± 8,0 años, el 56,4% eran mujeres y el IMC medio fue de 26,3 ± 5,5 kg / m2. Se informó de antecedentes familiares de cáncer colorrectal en el 23,8% de los pacientes. Las tasas generales de detección de pólipos y adenomas fueron del 22% y el 14%, respectivamente. La mayoría de los pólipos eran adenomatosos (58,9% de todas las polipectomías) y estaban localizados en colon izquierdo o recto (61,4%). Las tasas de detección de adenomas, neoplasias avanzadas y adenocarcinomas fueron más altas en pacientes de 45 a 49 años (19,3%, 4,8% y 1,3%, respectivamente). En el análisis multivariado, las variables asociadas de forma independiente con la detección de adenomas incluyeron: edad (OR 1.08; IC del 95%: 1,06-1,1), sexo femenino (OR 1,80; IC del 95%: 1,44-2,27), IMC (OR 1,01; IC del 95%: 1,01-1,05)) y haber sido sometido a una colonoscopia diagnóstica (OR 1,81; IC 95% 1,44-2,29). En el análisis de subgrupos de pacientes de 45 a 49 años, las mismas variables permanecieron asociadas con la detección de adenomas, excepto la edad.LIMITACIONES:Carácter retrospectivo con datos heterogéneos.CONCLUSIONES:La detección de adenomas en adultos jóvenes de 45 a 49 años se acerca a la detección actual de adenomas en adultos mayores. Los predictores de la detección de adenomas en estos adultos jóvenes son el sexo femenino y el IMC, que pueden ayudar a guiar las pautas de detección del cáncer colorrectal en el futuro. Consulte Video Resumen en http://links.lww.com/DCR/B843. (Traducción-Dr. Hagerman).

Clinician based decision tool to guide recommended interval between colonoscopies: development and evaluation pilot study

Background

Optimal intervals between repeat colonoscopies could improve patient outcomes and reduce costs. We evaluated: (a) concordance between clinician and guideline recommended colonoscopy screening intervals in Winnipeg, Manitoba, (b) clinician opinions about the utility of an electronic decision-making tool to aid in recommending screening intervals, and (c) the initial use of a decision-making smartphone/web-based application.

Methods

Clinician endoscopists and primary care providers participated in four focus groups (N = 22). We asked participating clinicians to evaluate up to 12 hypothetical scenarios and compared their recommended screening interval to those of North American guidelines. Fisher’s exact tests were used to assess differences in agreement with guidelines. We developed a decision-making tool and evaluated it via a pilot study with 6 endoscopists.

Result

53% of clinicians made recommendations that agreed with guidelines in ≤ 50% of the hypothetical scenarios. Themes from focus groups included barriers to using a decision-making tool: extra time to use it, less confidence in the results of the tool over their own judgement, and having access to the information required by the tool (e.g., family history). Most were willing to try a tool if it was quick and easy to use. Endoscopists participating in the tool pilot study recommended screening intervals discordant with guidelines 35% of the time. When their recommendation differed from that of the tool, they usually endorsed their own over the guideline.

Conclusions

Endoscopists are overconfident and inconsistent with applying guidelines in their polyp surveillance interval recommendations. Use of a decision tool may improve knowledge and application of guidelines. A change in practice may require that the tool be coupled with continuing education about evidence for improved outcomes if guidelines are followed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12911-022-01872-z.

Boundary Constraint Network with Cross Layer Feature Integration for Polyp Segmentation

Clinically, proper polyp localization in endoscopy images plays a vital role in the follow-up treatment (e.g., surgical planning). Deep convolutional neural networks (CNNs) provide a favoured prospect for automatic polyp segmentation and evade the limitations of visual inspection, e.g., subjectivity and overwork. However, most existing CNNs-based methods often provide unsatisfactory segmentation performance. In this paper, we propose a novel boundary constraint network, namely BCNet, for accurate polyp segmentation. The success of BCNet benefits from integrating cross-level context information and leveraging edge information. Specifically, to avoid the drawbacks caused by simple feature addition or concentration, BCNet applies a cross-layer feature integration strategy (CFIS) in fusing the features of the top-three highest layers, yielding a better performance. CFIS consists of three attention-driven cross-layer feature interaction modules (ACFIMs) and two global feature integration modules (GFIMs). ACFIM adaptively fuses the context information of the top-three highest layers via the self-attention mechanism instead of direct addition or concentration. GFIM integrates the fused information across layers with the guidance from global attention. To obtain accurate boundaries, BCNet introduces a bilateral boundary extraction module that explores the polyp and non-polyp information of the shallow layer collaboratively based on the high-level location information and boundary supervision. Through joint supervision of the polyp area and boundary, BCNet is able to get more accurate polyp masks. Experimental results on three public datasets show that the proposed BCNet outperforms seven state-of-the-art competing methods in terms of both effectiveness and generalization.

An Estimate of the US Rate of Overuse of Screening Colonoscopy: a Systematic Review

BACKGROUND

This study aims to assess the rate at which screening colonoscopy is performed on patients younger or older than the age range specified in national guidelines, or at shorter intervals than recommended. Such non-indicated use of the procedure is considered low-value care, or overuse. This study is the first systematic review of the rate of non-indicated completed screening colonoscopy in the USA.

METHODS

PubMed and Embase were queried for relevant studies on overuse of screening colonoscopy published from January 1, 2002, until January 23, 2019. English-language studies that were conducted for screening colonoscopy after 2001 for average-risk patients were included. Studies must have followed national guidelines for detecting rates of overuse. We followed methods outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the reporting recommendations of the Meta-analysis of Observational Studies in Epidemiology group (MOOSE).

RESULTS

A total of 772 papers were reviewed for inclusion; 42 were reviewed in full text. Of those reviewed, six studies met eligibility criteria, including a total of 459,503 colonoscopies of which 242,756 were screening colonoscopies. The rate of overuse ranged credibly from 17 to 25.7%.

DISCUSSION

This study demonstrates that screening colonoscopy is regularly performed in the USA more often, and in populations older or younger, than recommended by national guidelines. Such overuse wastes resources and places patients at unnecessary risk of harm. Efforts to reduce non-indicated screening colonoscopy are needed.

Disparities in Recommendations for Colorectal Cancer Screening Among Average-Risk Individuals: An Ecobiosocial Approach

Regardless of the high global burden of colorectal cancer (CRC), the uptake of CRC screening varies across countries. This systematic review aimed to provide a picture of the disparities in recommendations for CRC screening in average-risk individuals using an ecobiosocial approach. It was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The literature search was conducted through Scopus, Web of Science, PubMed, and EBSCOHost. Full-text guidelines which were published between 2011 and 2021, along with guidelines which provided recommendations on CRC screening in average-risk individuals, were included in the review. However, guidelines focusing only on a single screening modality were excluded. Fourteen guidelines fulfilling the eligibility criteria were retained for the final review and analysis. Quality assessment of each guideline was performed using the AGREE II instrument. Disparities in guidelines identified in this review were classified into ecological (screening modalities and strategies), biological (recommended age, gender and ethnicities), and social (smoking history, socioeconomic status, and behavior) factors. In general, unstandardized practices in CRC screening for average-risk individuals are likely attributable to the inconsistent and non-specific recommendations in the literature. This review calls on stakeholders and policymakers to review the existing colorectal cancer screening practices and pursue standardization.

Applicability of the USPSTF Lung Cancer Screening Guidelines in a Predominantly Black Veteran Population

BACKGROUND

Black individuals and veterans are at higher risk for developing lung cancer compared with that of the general population. Evidence suggests the screening criteria have been too conservative for this population.

METHODS

This study is a retrospective chart review examining the applicability of the 2013 United States Preventive Services Task Force lung cancer screening guidelines in a US Department of Veteran Affairs institution that served a a predominantly black population. Patients diagnosed with stage 1 or 2 lung cancer from 2005 through 2017 were included and grouped by whether or not they met United States Preventive Services Task Force screening criteria.

RESULTS

There was a significantly higher proportion of Black patients in the study group that did not meet screening criteria (68% vs 54%, P = .04), highlighting the concern that this population was being underscreened with the 2013 guidelines.

CONCLUSIONS

An individualized, risk-based screening model could be more effective at diagnosing early-stage lung cancer and requires more investigation.

Factors Associated With Clinician Recommendations for Colorectal Cancer Screening Among Average-Risk Patients: Data From a National Survey

Introduction

Colorectal cancer (CRC) screening among average-risk patients is underused in the US. Clinician recommendation is strongly associated with CRC screening completion. To inform interventions that improve CRC screening uptake among average-risk patients, we examined clinicians’ routine recommendations of 7 guideline-recommended screening methods and factors associated with these recommendations.

Methods

We conducted an online survey in November and December 2019 among a sample of primary care clinicians (PCCs) and gastroenterologists (GIs) from a panel of US clinicians. Clinicians reported whether they routinely recommend each screening method, screening method intervals, and patient age at which they stop recommending screening. We also measured the influence of various factors on screening recommendations.

Results

Nearly all 814 PCCs (99%) and all 159 GIs (100%) reported that they routinely recommend colonoscopy for average-risk patients, followed by stool-based tests (more than two-thirds of PCCs and GIs). Recommendation of other visualization-based methods was less frequent (PCCs, 26%–35%; GIs, 30%–41%). A sizable proportion of clinicians reported guideline-discordant screening intervals and age to stop screening. Guidelines and clinical evidence were most frequently reported as very influential to clinician recommendations. Factors associated with routine recommendation of each screening method included clinician-perceived effectiveness of the method, clinician familiarity with the method, Medicare coverage, clinical capacity, and patient adherence.

Conclusion

Clinician education is needed to improve knowledge, familiarity, and experience with guideline-recommended screening methods with the goal of effectively engaging patients in informed decision making for CRC screening.

Risk Stratification for Early-Onset Colorectal Cancer Using a Combination of Genetic and Environmental Risk Scores: An International Multi-Center Study

BACKGROUND

The incidence of colorectal cancer (CRC) among individuals aged younger than 50 years has been increasing. As screening guidelines lower the recommended age of screening initiation, concerns including the burden on screening capacity and costs have been recognized, suggesting that an individualized approach may be warranted. We developed risk prediction models for early-onset CRC that incorporate an environmental risk score (ERS), including 16 lifestyle and environmental factors, and a polygenic risk score (PRS) of 141 variants.

METHODS

Relying on risk score weights for ERS and PRS derived from studies of CRC at all ages, we evaluated risks for early-onset CRC in 3486 cases and 3890 controls aged younger than 50 years. Relative and absolute risks for early-onset CRC were assessed according to values of the ERS and PRS. The discriminatory performance of these scores was estimated using the covariate-adjusted area under the receiver operating characteristic curve.

RESULTS

Increasing values of ERS and PRS were associated with increasing relative risks for early-onset CRC (odds ratio per SD of ERS = 1.14, 95% confidence interval [CI] = 1.08 to 1.20; odds ratio per SD of PRS = 1.59, 95% CI = 1.51 to 1.68), both contributing to case-control discrimination (area under the curve = 0.631, 95% CI = 0.615 to 0.647). Based on absolute risks, we can expect 26 excess cases per 10 000 men and 21 per 10 000 women among those scoring at the 90th percentile for both risk scores.

CONCLUSIONS

Personal risk scores have the potential to identify individuals at differential relative and absolute risk for early-onset CRC. Improved discrimination may aid in targeted CRC screening of younger, high-risk individuals, potentially improving outcomes.

Quality Indicators for the Detection and Removal of Colorectal Polyps and Interventions to Improve Them

Modifiable risk factors for postcolonoscopy colorectal cancer include suboptimal lesion detection (missed neoplasms) and inadequate lesion removal (incomplete polypectomy) during colonoscopy. Competent detection and removal of colorectal polyps are thus fundamental to ensuring adequate colonoscopy quality. Several well-researched quality metrics for polyp detection have been implemented into clinical practice, chief among these the adenoma detection rate. Less data are available on quality indicators for polyp removal, which currently include complete resection rates and skills assessment tools. This review summarizes the available literature on quality indicators for the detection and removal of colorectal polyps, as well as interventions to improve them.

Surveillance Recommendation for Colonoscopy after Polypectomy

The incidence and mortality of colorectal cancer (CRC) have declined over the past several decades, largely due to improvement and uptake in screening, particularly with colonoscopy. The US Multi-Society Task Force on CRC published guidelines for surveillance after polypectomy in 2012, which were updated in 2020 with some important changes, and this review will provide an updated overview of evidence and outcomes of surveillance after polypectomy. Notable modifications to surveillance guidelines include increasing interval time between colonoscopies from 5 to 7 to 10 years for 1 to 2 low-risk adenomas (<10 mm) and from 3 years to 3 to 5 years when 3 to 4 low-risk adenomas are identified.

Cancer Statistics over Time in Northwestern São Paulo State, Brazil: Incidence and Mortality

BACKGROUND

Population studies can serve as an essential source of information on cancer's etiology, and assessments of cancer trends over time can detect changes. This study aimed to provide statistics over time on cancer incidence and mortality in the Barretos Region, Brazil.

METHODS

Cancer incidence data were obtained from the population-based cancer registry of the Barretos Region, and mortality data were obtained from the Official Federal Database from 2002 to 2016. Age-standardized rates for incidence and mortality were calculated. Joinpoint Regression software was used to estimate the average annual percentage changes (AAPC).

RESULTS

Age-standardized rates of incidence increased significantly for colon cancer (AAPC: 2.2), rectum and rectosigmoid (AAPC: 2.4), liver (AAPC: 4.7), female breast (AAPC: 2.2), and thyroid cancer (AAPC: 3.8) but decreased for esophageal (AAPC: -3.2), stomach (AAPC: -4.2), lung (AAPC: -2.0), and ovarian cancer (AAPC: -5.6). The mortality increased for liver cancer (AAPC: 2.3) and decreased for pharyngeal cancer (AAPC: -5.8), stomach cancer (AAPC: -6.6), cervical uterine cancer (AAPC: -5.9), prostate cancer (AAPC: -2.4), and ovarian cancer (AAPC: -3.3).

CONCLUSIONS

We observed decreases in some cancers related to tobacco smoking and cervical and stomach cancers related to infectious agents, showing strong regional and national prevention programs' successes. But, we also observed rises in many cancer sites linked to lifestyle factors, such as breast or colorectal cancer, without a sign of declining mortality.

IMPACT

These results can impact and support cancer control program implementation and improvement at the community level and extrapolate to the state level and/or the whole country.

Polypectomy for Diminutive and Small Colorectal Polyps

Diminutive and small colorectal polyps are common findings during colonoscopies, and rarely contain dysplastic elements and progress to colorectal cancer. With improving technology and the advent of artificial intelligence, detection rates of small or diminutive polyps and adenomas are rising, resulting in increasing costs associated with colonoscopy. Incomplete resection rates are an outcome of interest because it correlates with interval colorectal cancer. More effort is warranted to standardize training programs and sensitize endoscopists to the importance of personal performance as a quality metric of colonoscopy. This article reviews indications, methods, and recent developments in polypectomy for small and diminutive polyps.

Cause, Epidemiology, and Histology of Polyps and Pathways to Colorectal Cancer

Colorectal cancer is the second leading cause of cancer-associated mortality, with a lifetime risk of approximately 4% to 5%. Colorectal cancer develops from the sequential acquisition of defined genetic mutations in the colonic epithelium. Tumorigenesis from normal tissue to cancer occurs largely through 3 pathways: the chromosomal instability pathway, the microsatellite instability pathway, and the sessile serrated pathway. Colorectal cancer incidence and mortality have decreased by approximately 35% since the beginning of screening programs in the 1990s, although other factors such as use of aspirin for coronary disease prevention and decreased smoking rates may also be important. In this review, we discuss the etiology, epidemiology, and histology of colorectal polyps and cancer.

Familial colorectal cancer

The introduction of average-risk colorectal cancer (CRC) screening programs means that many subjects with family history of CRC and without well-described inherited syndromes can benefit from these public health policies. Therefore, the definition of which individuals should be named under the umbrella of the term "familial CRC" should be reconsidered to include only those who are outside of the protection of population-based screening and need to be moved towards a more intensive surveillance strategy. Two subgroups have been reported as having a high enough CRC risk to be included within the term "familial risk of CRC": individuals who have ≥1 first degree relative (FDR) with CRC diagnosed at age <50 years, and those who have ≥2 FDRs with CRC. Colonoscopy-based screening starting at age 40 years is proposed as the most accepted recommendation for these individuals. Finally, the evolution of Lynch syndrome screening from clinical criteria to tumor tissue analysis and new tools for screening pathogenic gene mutations associated with cancer susceptibility in individuals with early-onset CRC might help to reduce misclassification of familial CRC.

A global view of adherence to colonoscopy follow-up in cascade screening of colorectal cancer

OBJECTIVE

To overview the colonoscopy adherence in cascade screening of colorectal cancer (CRC) and evaluate potential influence of the initial tests based on an ecological evaluation.

METHODS

The performance of the initial screening tests and adherence to subsequent colonoscopy were extracted from relevant studies published up to 16 October 2020. The age-standardised incidence (ASRi) of CRC in populations in the year of screening was derived from the Cancer Statistics.

RESULTS

One hundred sixty-six observational studies and 60 experimental studies were identified. Most studies applied cascade screening with faecal occult blood tests (FOBTs) as an initial test. The adherence to colonoscopy varied greatly across populations by continents, gross national income and type of initial tests, with a median (interquartile range) of 79.8% (63.1%-87.8%) in observational studies and 82.1% (66.7%-90.4%) in randomised trials. The adherence was positively correlated with the ASRi of CRC (r = 0.145, p = 0.023) and positive predictive value (PPV) of the initial tests (r = 0.206, p = 0.002) in observational studies and correlated with ASRi of CRC (r = 0.309, p = 0.002) and sensitivity of the initial tests (r = -0.704, p = 0.003) in experimental studies.

CONCLUSIONS

Adherence to colonoscopy varies greatly across populations and is related with performance of the initial tests, indicating the importance to select appropriate initial tests.

Masculinity Barriers to Ever Completing Colorectal Cancer Screening among American Indian/Alaska Native, Black, and White Men (Ages 45-75)

Disparities in colorectal cancer (CRC) mortality among White, Black, and American Indian/Alaska Native (AIAN) men are attributable to differences in early detection screening. Determining how masculinity barriers influence CRC screening completion is critical for cancer prevention and control. To determine whether masculinity barriers to medical care are associated with lower rates of ever completing CRC screening, a survey-based study was employed from December 2020-January 2021 among 435 White, Black, and AIAN men (aged 45-75) who resided in the US. Logistic regression models were fit to four Masculinity Barriers to Medical Care subscales predicting ever completing CRC screening. For all men, being strong was associated with 54% decreased odds of CRC screening completion (OR 0.46, 95% CI 0.23 to 0.94); each unit increase in negative attitudes toward medical professionals and exams decreased the odds of ever completing CRC screening by 57% (OR 0.43, 95% CI 0.21 to 0.86). Black men who scored higher on negativity toward medical professionals and exams had decreased odds of ever screening. Consideration of masculinity in future population-based and intervention research is critical for increasing men's participation in CRC screening, with more salience for Black men.

Post-Acquisition Hyperpolarized 29Silicon Magnetic Resonance Image Processing for Visualization of Colorectal Lesions Using a User-Friendly Graphical Interface

Medical imaging devices often use automated processing that creates and displays a self-normalized image. When improperly executed, normalization can misrepresent information or result in an inaccurate analysis. In the case of diagnostic imaging, a false positive in the absence of disease, or a negative finding when disease is present, can produce a detrimental experience for the patient and diminish their health prospects and prognosis. In many clinical settings, a medical technical specialist is trained to operate an imaging device without sufficient background information or understanding of the fundamental theory and processes involved in image creation and signal processing. Here, we describe a user-friendly image processing algorithm that mitigates user bias and allows for true signal to be distinguished from background. For proof-of-principle, we used antibody-targeted molecular imaging of colorectal cancer (CRC) in a mouse model, expressing human MUC1 at tumor sites. Lesion detection was performed using targeted magnetic resonance imaging (MRI) of hyperpolarized silicon particles. Resulting images containing high background and artifacts were then subjected to individualized image post-processing and comparative analysis. Post-acquisition image processing allowed for co-registration of the targeted silicon signal with the anatomical proton magnetic resonance (MR) image. This new methodology allows users to calibrate a set of images, acquired with MRI, and reliably locate CRC tumors in the lower gastrointestinal tract of living mice. The method is expected to be generally useful for distinguishing true signal from background for other cancer types, improving the reliability of diagnostic MRI.

Epidemiology and biology of early onset colorectal cancer

Colorectal cancer (CRC) is the third leading cause of cancer-related mortality in men or women in the United States. Average-risk screening that begins at age 50 years has reduced incidence and mortality of CRC in those over 50 years of age, whereas CRC incidence in those under age 50 years (early onset colorectal cancer (eoCRC)) has recently and dramatically increased. In this review, we summarize the recent literature including risk factors for eoCRC, differences in clinicopathologic presentation and outcomes in eoCRC, and emerging evidence regarding the molecular pathways that are altered in eoCRC compared to later onset CRC (loCRC). Epidemiologic studies of eoCRC show predominance in distal colon and rectum, and association with several modifiable risk factors, including diabetes, obesity, diet, sedentary time, alcohol consumption and smoking. Data regarding potential risk factors of prior antibiotic exposure and microbiome alterations or direct carcinogen exposure are still emerging. Aggressive clinicopathologic features of eoCRC at presentation may be due to delay in diagnosis or more aggressive tumor biology. EoCRC outcomes are similar to loCRC when matched for stage, but overall mortality is greater due to higher frequency of advanced disease at a younger presentation, with more life-years lost. There are only few molecular evaluations of eoCRC to date, with findings of potential increase in TP53 and CTNNB1 somatic mutation and decrease in APC, KRAS and BRAF somatic mutation, compared to loCRC. Other findings include LINE-1 hypomethylation, absence of microsatellite instability (MSI-H), presence of chromosomal instability (CIN) or microsatellite and chromosomal stability (MACS). These studies are only now emerging and have not yet identified a specific molecular signature defining eoCRC. Further research evaluating genetic and molecular differences as well as environmental triggers for eoCRCs should provide a clearer understanding to inform targeted screening for pre-symptomatic at-risk younger individuals.

AGA Clinical Practice Update on Approach to the Use of Noninvasive Colorectal Cancer Screening Options: Commentary

The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update Commentary is to review the available evidence and provide expert advice regarding the approach to using noninvasive colorectal cancer (CRC) screening options, including evidence for their effectiveness, selection of individuals for whom these tests are appropriate, implications of a positive non-colonoscopy screening test, and opportunities to enhance the quality of noninvasive CRC screening programs. This Clinical Practice Update was commissioned and approved by the AGA Institute Clinical Practice Updates Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership, and underwent internal peer review by the Clinical Practice Updates Committee and external peer review through standard procedures of Gastroenterology. This expert commentary reflects recently published studies in this field, as well as the experiences of the authors who are gastroenterologists with high-level expertise in CRC screening and prevention.

Relationship between Health Literacy and Knowledge, Compliance with Bowel Preparation, and Bowel Cleanliness in Older Patients Undergoing Colonoscopy

Compared to young adults, it is difficult for the older people with relatively low health literacy to perform proper bowel preparation for a colonoscopy. This study aims to identify the relationship between knowledge, compliance with bowel preparation, and bowel cleanliness with health literacy in older patients undergoing colonoscopy. The participants were 110 older people undergoing colonoscopy, recruited from an endoscopy hospital in G metropolitan city, South Korea. Data obtained from a structured questionnaire that included items on health literacy and knowledge of and compliance with bowel preparation, and the Aronchick bowel cleanliness scale. The data were analyzed using descriptive statistics, χ-test, Pearson's correlation, t-test, and ANCOVA. Participants who were younger and those with a higher education level and better economic status had a statistically significantly higher health literacy level. Older people with a health literacy level of 7 points and above had a higher knowledge level and bowel cleanliness index, a showed better compliance with bowel preparation. The results highlight the need for developing a customized education intervention program that can improve health literacy for successful bowel preparation and examination of the older population undergoing colonoscopy.

Impact of 9-Minute Withdrawal Time on the Adenoma Detection Rate: A Multicenter Randomized Controlled Trial

BACKGROUND & AIMS

Although current quality indicators of colonoscopy recommend 6 minutes as the minimum standard for withdrawal time (WT), the impact of a WT longer than 6 minutes on neoplasia detection is unclear.

METHODS

A multicenter randomized controlled trial involving 1027 patients was conducted from January 2018 to July 2019. Participants were randomly divided into a 9-minute (n = 514) and 6-minute (n = 513) WT group, and a timer was used to adjust the withdrawal speed. The primary outcome was the adenoma detection rate (ADR).

RESULTS

Intention-to-treat analysis showed a significantly higher ADR in the 9-minute versus 6-minute WT group (36.6% vs. 27.1%, P = .001). Prolonging WT from 6 to 9 minutes significantly increased ADR of the proximal colon (21.4% vs. 11.9%, P < .001) as well as of the less experienced colonoscopists (36.8% vs. 23.5%, P = .001). Improvements were also observed in the polyp detection rate (58.0% vs. 47.8%, P < .001), and mean number of polyps and adenomas detected per colonoscopy (1.1 vs. 0.9, P = .002; 0.5 vs. 0.4, P = .008, respectively). The higher ADRs in 9-minute WT were also confirmed by the per-protocol (PP) analysis and subgroup analyses, with an increased rate of sessile serrated lesion detection in the 9-minute WT by PP analysis (4.0% vs. 1.3%, P = .04). Multivariate logistic regression demonstrated that the 9-minute WT was independently associated with increased ADR (P = .005).

CONCLUSIONS

Prolonging WT from 6 to 9 minutes significantly improved ADR, especially in the proximal colon and for less experienced colonoscopists. A 9-minute WT benchmark should be considered as one of the quality indicators of colonoscopy. ClinicalTrials.gov (identifier, NCT03399045).

Cancer Risk in Patients With and Relatives of Serrated Polyposis Syndrome and Sporadic Sessile Serrated Lesions

INTRODUCTION

Patients with serrated polyposis syndrome (SPS) and their first-degree relatives (FDRs) have increased colorectal cancer (CRC) risk. Patients with sporadic sessile serrated lesion (SSL) have risk for progression to CRC. Yet familial risks of common extracolonic cancers and even CRC in these cohorts are poorly understood. Our aim was to examine cancer risk for patients with SPS and sporadic SSL and their close and more distant relatives using a large population database.

METHODS

Patients with SPS (n = 59) from hereditary patient registries were eligible for study. Sporadic SSL (n = 754) and sex- and age-matched normal colonoscopy controls (n = 1,624) were selected from clinical data linked to the Utah Population Database. Cox models adjusting for the number of relatives, degree of relatedness, and person-years at risk were used to estimate CRC, extracolonic, and any-site adenocarcinoma/carcinoma cancer risk in patients and their relatives.

RESULTS

Compared with controls, CRC risk was elevated 10-fold in patients with SPS (P = 0.04) and 5-fold in their FDRs (P = 0.001). Any-site adenoma/carcinoma risk was increased 2.6-fold in FDRs of patients with SPS. No elevated risks of other common extracolonic cancers were observed in SPS and family members. The FDRs, second-degree relatives, and third-degree relatives of patients with both SSL and adenomatous polyps exhibited a 50% increased CRC risk.

DISCUSSION

Patients with SPS and their FDRs have an increased CRC risk, confirming other reports. Interestingly, patients with SSL were noted to have an increased risk of prostate cancer. Relatives of individuals with both sporadic SSL and adenomas, irrespective of size or dysplasia on examination, may have an elevated CRC risk, suggesting closer colonoscopy surveillance in this population.

Burden and Cost of Gastrointestinal, Liver, and Pancreatic Diseases in the United States: Update 2021

BACKGROUND & AIMS

Gastrointestinal diseases account for considerable health care use and expenditures. We estimated the annual burden, costs, and research funding associated with gastrointestinal, liver, and pancreatic diseases in the United States.

METHODS

We generated estimates using data from the National Ambulatory Medical Care Survey; National Hospital Ambulatory Medical Care Survey; Nationwide Emergency Department Sample; National Inpatient Sample; Kids' Inpatient Database; Nationwide Readmissions Database; Surveillance, Epidemiology, and End Results program; National Vital Statistics System; Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research; MarketScan Commercial Claims and Encounters data; MarketScan Medicare Supplemental data; United Network for Organ Sharing registry; Medical Expenditure Panel Survey; and National Institutes of Health (NIH).

RESULTS

Gastrointestinal health care expenditures totaled $119.6 billion in 2018. Annually, there were more than 36.8 million ambulatory visits for gastrointestinal symptoms and 43.4 million ambulatory visits with a primary gastrointestinal diagnosis. Hospitalizations for a principal gastrointestinal diagnosis accounted for more than 3.8 million admissions, with 403,699 readmissions. A total of 22.2 million gastrointestinal endoscopies were performed, and 284,844 new gastrointestinal cancers were diagnosed. Gastrointestinal diseases and cancers caused 255,407 deaths. The NIH supported $3.1 billion (7.5% of the NIH budget) for gastrointestinal research in 2020.

CONCLUSIONS

Gastrointestinal diseases are responsible for millions of health care encounters and hundreds of thousands of deaths that annually costs billions of dollars in the United States. To reduce the high burden of gastrointestinal diseases, focused clinical and public health efforts, supported by additional research funding, are warranted.

Deep learning in CT colonography: differentiating premalignant from benign colorectal polyps

Objectives

To investigate the differentiation of premalignant from benign colorectal polyps detected by CT colonography using deep learning.

Methods

In this retrospective analysis of an average risk colorectal cancer screening sample, polyps of all size categories and morphologies were manually segmented on supine and prone CT colonography images and classified as premalignant (adenoma) or benign (hyperplastic polyp or regular mucosa) according to histopathology. Two deep learning models SEG and noSEG were trained on 3D CT colonography image subvolumes to predict polyp class, and model SEG was additionally trained with polyp segmentation masks. Diagnostic performance was validated in an independent external multicentre test sample. Predictions were analysed with the visualisation technique Grad-CAM++.

Results

The training set consisted of 107 colorectal polyps in 63 patients (mean age: 63 ± 8 years, 40 men) comprising 169 polyp segmentations. The external test set included 77 polyps in 59 patients comprising 118 polyp segmentations. Model SEG achieved a ROC-AUC of 0.83 and 80% sensitivity at 69% specificity for differentiating premalignant from benign polyps. Model noSEG yielded a ROC-AUC of 0.75, 80% sensitivity at 44% specificity, and an average Grad-CAM++ heatmap score of ≥ 0.25 in 90% of polyp tissue.

Conclusions

In this proof-of-concept study, deep learning enabled the differentiation of premalignant from benign colorectal polyps detected with CT colonography and the visualisation of image regions important for predictions. The approach did not require polyp segmentation and thus has the potential to facilitate the identification of high-risk polyps as an automated second reader.

Key Points

• Non-invasive deep learning image analysis may differentiate premalignant from benign colorectal polyps found in CT colonography scans.

• Deep learning autonomously learned to focus on polyp tissue for predictions without the need for prior polyp segmentation by experts.

• Deep learning potentially improves the diagnostic accuracy of CT colonography in colorectal cancer screening by allowing for a more precise selection of patients who would benefit from endoscopic polypectomy, especially for patients with polyps of 6–9 mm size.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-08532-2.

Variation of Positive Predictive Values of Fecal Immunochemical Tests by Polygenic Risk Score in a Large Screening Cohort

INTRODUCTION

Prevalence of colorectal neoplasms varies by polygenic risk scores (PRS). We aimed to assess to what extent a PRS might be relevant for defining personalized cutoff values for fecal immunochemical tests (FITs) in colorectal cancer screening.

METHODS

Among 5,306 participants of screening colonoscopy who provided a stool sample for a quantitative FIT (Ridascreen Hemoglobin or FOB Gold) before colonoscopy, a PRS was determined, based on the number of risk alleles in 140 single nucleotide polymorphisms. Subjects were classified into low, medium, and high genetic risk of colorectal neoplasms according to PRS tertiles. We calculated positive predictive values (PPVs) and numbers needed to scope (NNS) to detect 1 advanced neoplasm (AN) by the risk group, and cutoff variation needed to achieve comparable PPVs across risk groups in the samples tested with Ridascreen (N = 1,271) and FOB Gold (N = 4,035) independently, using cutoffs yielding 85%, 90%, or 95% specificity.

RESULTS

Performance of both FITs was very similar within each PRS group. For a given cutoff, PPVs were consistently higher by 11%-15% units in the high-risk PRS group compared with the low-risk group (all P values < 0.05). Correspondingly, NNS to detect 1 advanced neoplasm varied from 2 (high PRS, high cutoff) to 5 (low PRS, low cutoff). Conversely, very different FIT cutoffs would be needed to ensure comparable PPVs across PRS groups.

DISCUSSION

PPVs and NNS of FITs varied widely across people with high and low genetic risk score. Further research should evaluate the relevance of these differences for personalized colorectal cancer screening.

The effect of chemotherapy on dietary intake and nutritional status in patients with colorectal neoplasms and the importance of nutritional counseling

PURPOSE

This study aimed at assessing the effect of chemotherapy on dietary intake and nutritional status of patients with colorectal cancer undergoing chemotherapy.

METHODS

Observational, cross-sectional study conducted with 35 patients of both sexes, aged 50 years or older. Dietary intake was assessed four times: before (T₀), twice during (T₁ and T₂), and after (T_F) chemotherapy. Data on energy, macronutrients, and micronutrients were used for assessing dietary intake. Nutritional status was assessed on the first day and at the end of the chemotherapy cycle. The data were treated statistically using a 5% significance level.

RESULTS

The intake of energy, carbohydrates, lipids, selenium, and iron was lower after chemotherapy infusion (p < 0.05). Energy consumption decreased when comparing T₀ (1419.8 ± 527.1 kcal) with T₁ (1181.9 ± 423.2 kcal). Regarding macronutrients, carbohydrates and lipids showed a drop (p < 0.05), but there were no differences in protein intake, and it was observed that the consumption of food sources such as dairy was prioritized. In the analysis of vitamins and minerals, vitamins dropped but without a significant difference. There were significant differences between T₁ and T_F for iron (9.7 mg ± 4.5 mg and 12.0 ± 4.0 mg) and selenium (77.4 ± 29.7 µg and 93.6 ± 37.8 µg). There was no change in body composition and nutritional status between chemotherapy cycles.

CONCLUSION

The treatment reduced patients' food consumption after the chemotherapy session and impacted dietary intake, which demonstrates the importance of nutritional counseling and intervention, especially on energy consumption.

Facilitators and Barriers to Implementing a Digital Informed Decision Making Tool in Primary Care: A Qualitative Study

BACKGROUND

Informed decision aids provide information in the context of the patient's values and improve informed decision making (IDM). To overcome barriers that interfere with IDM, our team developed an innovative iPad-based application (aka "app") to help patients make informed decisions about colorectal cancer screening. The app assesses patients' eligibility for screening, educates them about their options, and empowers them to request a test via the interactive decision aid.

OBJECTIVE

The aim of the study is to explore how informed decision aids can be implemented successfully in primary care clinics, including the facilitators and barriers to implementation; strategies for minimizing barriers; adequacy of draft training materials; and any additional support or training desired by clinics.

DESIGN

This work deals with a multicenter qualitative study in rural and urban settings.

PARTICIPANTS

A total of 48 individuals participated including primary care practice managers, clinicians, nurses, and front desk staff.

APPROACH

Focus groups and semi-structured interviews, with data analysis were guided by thematic analysis.

KEY RESULTS

Salient emergent themes were time, workflow, patient age, literacy, and electronic health record (EHR) integration. Saving time was important to most participants. Patient flow was a concern for all clinic staff, and they expressed that any slowdown due to patients using the iPad module or perceived additional work to clinic staff would make staff less motivated to use the program. Participants voiced concern about older patients being unwilling or unable to utilize the iPad and patients with low literacy ability being able to read or comprehend the information.

CONCLUSION

Integrating new IDM apps into the current clinic workflow with minimal disruptions would increase the probability of long-term adoption and ultimate sustainability.

NIH TRIAL REGISTRY NUMBER

R01CA218416-A1.

Membrane Bound Peroxiredoxin-1 Serves as a Biomarker for In Vivo Detection of Sessile Serrated Adenomas

Aim: Sessile serrated adenomas (SSAs) are premalignant lesions driven by the BRAF^V600E mutation to give rise to colorectal cancers (CRCs). They are often missed during white light colonoscopy because of their subtle appearance. Previously, a fluorescently labeled 7mer peptide KCCFPAQ was shown to detect SSAs in vivo. We aim to identify the target of this peptide. Results: Peroxiredoxin-1 (Prdx1) was identified as the binding partner of the peptide ligand. In vitro binding assays and immunofluorescence staining of human colon specimens ex vivo supported this result. Prdx1 was overexpressed on the membrane of cells with the BRAF^V600E mutation, and this effect was dependent on oxidative stress. RKO cells harboring the BRAF^V600E mutation and human SSA specimens showed higher oxidative stress as well as elevated levels of Prdx1 on the cell membrane. Innovation and Conclusion: These results suggest that Prdx1 is overexpressed on the cell surface in the presence of oxidative stress and can serve as an imaging biomarker for in vivo detection of SSAs. Antioxid. Redox Signal. 36, 39-56.

Increasing Colorectal Cancer Incidence Before and After Age 50: Implications for Screening Initiation and Promotion of "On-Time" Screening

BACKGROUND

Early onset colorectal cancer (CRC) incidence is rising under age 50, with a birth cohort effect for increasing incidence among individuals born 1950 and later. It is unclear whether increasing incidence trends will confer increased risk beyond age 50, the previously most commonly recommended age to initiate screening, when screening availability might modify incidence trends.

AIM

Evaluate US trends in colorectal cancer (CRC) for ages 40-59 years.

METHODS

We analyzed counts and incidence rates for CRC, including by anatomic subsite, using the US Cancer Statistics dataset covering 100% of the population 2003-2017. Joinpoint regression was used to quantify Average Annual Percent Change (AAPC) in cancer incidence by age subgroup.

RESULTS

470,458 CRC cases were observed age 40-59, with absolute numbers of rectal (n = 4173) and distal cases (n = 3327) per year for age 50-54 approaching age 55-59 cases for rectal (n = 4566) and distal (n = 3682) cancer by 2017. Increasing early onset rectal cancer incidence per 100,000 occuring under age 50 was observed to extend to age 50-54, from 4.9 to 6.3 for age 40-44 (AAPC 2.1; 95% CI 1.5-2.7), 9.3 to 12.0 for age 45-49 (AAPC 1.5; 95% CI 1.1-1.4), and from 16.7 to 19.5 for age 50-54 (AAPC 1.0; 95% CI 0.7-1.3).

CONCLUSIONS

CRC trends suggest observed increased risks under age 50 are also present after age 50, despite prior availability of screening for this group. Recent CRC trends support initiation of screening earlier than age 50, and promotion of "on-time" screening initiation.

Diagnostic Accuracy of Wireless Capsule Endoscopy in Polyp Recognition Using Deep Learning: A Meta-Analysis

AIM

As the completed studies have small sample sizes and different algorithms, a meta-analysis was conducted to assess the accuracy of WCE in identifying polyps using deep learning.

METHOD

Two independent reviewers searched PubMed, Embase, the Web of Science, and the Cochrane Library for potentially eligible studies published up to December 8, 2021, which were analysed on a per-image basis. STATA RevMan and Meta-DiSc were used to conduct this meta-analysis. A random effects model was used, and a subgroup and regression analysis was performed to explore sources of heterogeneity.

RESULTS

Eight studies published between 2017 and 2021 included 819 patients, and 18,414 frames were eventually included in the meta-analysis. The summary estimates for the WCE in identifying polyps by deep learning were sensitivity 0.97 (95% confidence interval (CI), 0.95-0.98); specificity 0.97 (95% CI, 0.94-0.98); positive likelihood ratio 27.19 (95% CI, 15.32-50.42); negative likelihood ratio 0.03 (95% CI 0.02-0.05); diagnostic odds ratio 873.69 (95% CI, 387.34-1970.74); and the area under the sROC curve 0.99.

CONCLUSION

WCE uses deep learning to identify polyps with high accuracy, but multicentre prospective randomized controlled studies are needed in the future.

Updates on Age to Start and Stop Colorectal Cancer Screening: Recommendations From the U.S. Multi-Society Task Force on Colorectal Cancer

This document is a focused update to the 2017 colorectal cancer (CRC) screening recommendations from the U.S. Multi-Society Task Force on Colorectal Cancer, which represents the American College of Gastroenterology, the American Gastroenterological Association, and the American Society for Gastrointestinal Endoscopy. This update is restricted to addressing the age to start and stop CRC screening in average-risk individuals and the recommended screening modalities. Although there is no literature demonstrating that CRC screening in individuals under age 50 improves health outcomes such as CRC incidence or CRC-related mortality, sufficient data support the U.S. Multi-Society Task Force to suggest average-risk CRC screening begin at age 45. This recommendation is based on the increasing disease burden among individuals under age 50, emerging data that the prevalence of advanced colorectal neoplasia in individuals ages 45 to 49 approaches rates in individuals 50 to 59, and modeling studies that demonstrate the benefits of screening outweigh the potential harms and costs. For individuals ages 76 to 85, the decision to start or continue screening should be individualized and based on prior screening history, life expectancy, CRC risk, and personal preference. Screening is not recommended after age 85.

Acromegaly and Colorectal Neoplasm: An Update

Acromegaly is a systemic disease caused by excessive inappropriate secretion of GH and IGF-I levels, resulting in many systemic complications, including cardiovascular, respiratory, metabolic diseases, and a possible increased risk of some neoplasias. Although many studies on acromegaly and cancer remain uncertain, most data indicate that colorectal cancer (CRC) incidence is increased in this population. The exact mechanism involved in the role of GH-IGF-I axis in CRC has not been fully explained, yet it is associated with local and circulating effects of GH and IGF-I on the colon, promoting angiogenesis, cell proliferation, risk of mutation, inhibition of tumor-suppressor genes and apoptosis, thus facilitating a tumor microenvironment. Nevertheless, population-based studies present controversial findings on CRC incidence and mortality. All worldwide guidelines and expert consensuses agree with the need for colonoscopic screening and surveillance in acromegaly, although there is no consensus regarding the best period to do this. This review aims to analyze the existing data on CRC and acromegaly, exploring its pathophysiology, epidemiological studies and their limitations, colonic polyp characteristics, overall cancer and CRC incidences and mortality, risk factors for colon cancer pathophysiology, and recommendation guideline aspects.