Comparing the effectiveness of competing tests for reducing colorectal cancer mortality: a network meta-analysis

Biostatistics for gastroenterologists. Part III - Mastering meta-analysis for beginners

Meta-analysis combines data from multiple independent studies to derive robust conclusions. This article provides an insightful guide to conducting meta-analyses with a particular focus on gastroenterology studies. The process of conducting a meta-analysis involves several systematic steps. Firstly, formulating a clear research question using the PICO format. Subsequently, a comprehensive literature search is conducted using databases like PubMed and Embase, followed by the establishment of inclusion and exclusion criteria to select eligible studies. Data extraction, quality assessment, and statistical analysis using suitable software are then undertaken. Key aspects of performing the meta-analysis include choosing between fixed-effects and random-effects models based on heterogeneity levels among studies. Calculating summary effect sizes and visualizing results through forest plots aid in interpreting outcomes effectively. This article emphasizes the significance of meta-analysis in evidence synthesis, illustrating its role in enhancing decision-making processes by providing more comprehensive and reliable conclusions. It quantifies relationships between variables, resolves conflicting findings, and increases statistical power by aggregating data. Meta-analysis stands as an indispensable tool in research and decision-making, requiring collaboration with statisticians for methodological rigor and accuracy.

Social determinants and participation in fecal occult blood test based colorectal cancer screening: A qualitative systematic review and meta-synthesis

ISSUE ADDRESSED

Colorectal cancer (CRC) screening through fecal occult blood testing (FOBT) has saved thousands of lives globally with multiple countries adopting comprehensive population wide screening programs. Participation rates in FOBT based CRC screening for the socially and economically disadvantaged remains low. The aim of this systematic review is to explore empirical evidence that will guide targeted interventions to improve participation rates within priority populations.

METHODS

PubMed, Embase, Scopus, Cinahl and PsycInfo were systematically searched from inception to 22 June 2022. Eligible studies contained qualitative evidence identifying barriers to FOBT based CRC screening for populations impacted by the social determinants of health. An inductive thematic synthesis approach was applied using grounded theory methodology, to explore descriptive themes and interpret these into higher order analytical constructs and theories.

RESULTS

A total of 8,501 publications were identified and screened. A total of 48 studies from 10 countries were eligible for inclusion, representing 2,232 subjects. Coding within included studies resulted in 30 key descriptive themes with a thematic frequency greater than 10%. Coded themes applied to four overarching, interconnected barriers driving inequality for priority populations: social, behavioural, economic and technical/interfaces. SO WHAT?: This study has highlighted the need for stronger patient/provider relationships to mitigate barriers to FOBT screening participation for diverse groups. Findings can assist health professionals and policy makers address the systemic exclusion of priority populations in cancer screening by moving beyond the responsibility of the individual to a focus on addressing the information asymmetry driving low value perceptions.

Colorectal cancer diagnostic biomarkers: Beyond faecal haemoglobin

Colorectal cancer (CRC) is the third most common cancer worldwide, and the second commonest cause of cancer deaths worldwide. One of the most important prognostic factors, and thus a potential target for improving cancer care, is the stage of cancer at diagnosis. Earlier stage diagnosis is associated with better prognosis and longer survival times after treatment. At the same time, the use of targeted therapies and immunotherapy is improving CRC outcomes. Diagnostic biomarkers are key to both early detection and prediction of treatment responses. Currently faecal immunochemical testing for haemoglobin is perhaps the most widespread CRC diagnostic biomarker. However other biomarkers are approved for clinical use and others are in the validation stage of research prior to clinical use. This review focuses on these the evidence behind these biomarkers, their current and potential future use.

Colorectal Cancer Screening in the Middle East: What, Why, Who, When, and How?

The incidence of colorectal cancer (CRC) in the Middle East is increasing, especially among those younger than 50 years. Risk factors including obesity, sedentary lifestyle, and dietary changes are associated with the epidemiologic shift and are a result of socioeconomic changes happening in the region. Worldwide, CRC screening is associated with decreased incidence and mortality of CRC, but screening uptake is still low in the Middle East because of cultural barriers and lack of awareness; in addition, most countries do not have national screening programs. Knowledge of CRC screening and participation rates vary among different countries, but overall they are low. Both primary and secondary prevention approaches are needed in the Middle East, and cost-effectiveness is important in choosing screening modalities. Although colonoscopy is considered the most robust screening method, stool-based testing may be an acceptable screening strategy in resource-limited settings, and focusing on high-risk individuals such as those with hereditary CRC might be the most cost-effective strategy. In addition to financial limitations in many countries in the Middle East, human displacement places an extra toll on cancer control strategies in the region.

Effectiveness of Colorectal Cancer (CRC) Screening on All-Cause and CRC-Specific Mortality Reduction: A Systematic Review and Meta-Analysis

(1) Background: The aim of this study was to pool and compare all-cause and colorectal cancer (CRC) specific mortality reduction of CRC screening in randomized control trials (RCTs) and simulation models, and to determine factors that influence screening effectiveness. (2) Methods: PubMed, Embase, Web of Science and Cochrane library were searched for eligible studies. Multi-use simulation models or RCTs that compared the mortality of CRC screening with no screening in general population were included. CRC-specific and all-cause mortality rate ratios and 95% confidence intervals were calculated by a bivariate random model. (3) Results: 10 RCTs and 47 model studies were retrieved. The pooled CRC-specific mortality rate ratios in RCTs were 0.88 (0.80, 0.96) and 0.76 (0.68, 0.84) for guaiac-based fecal occult blood tests (gFOBT) and single flexible sigmoidoscopy (FS) screening, respectively. For the model studies, the rate ratios were 0.45 (0.39, 0.51) for biennial fecal immunochemical tests (FIT), 0.31 (0.28, 0.34) for biennial gFOBT, 0.61 (0.53, 0.72) for single FS, 0.27 (0.21, 0.35) for 10-yearly colonoscopy, and 0.35 (0.29, 0.42) for 5-yearly FS. The CRC-specific mortality reduction of gFOBT increased with higher adherence in both studies (RCT: 0.78 (0.68, 0.89) vs. 0.92 (0.87, 0.98), model: 0.30 (0.28, 0.33) vs. 0.92 (0.51, 1.63)). Model studies showed a 0.62-1.1% all-cause mortality reduction with single FS screening. (4) Conclusions: Based on RCTs and model studies, biennial FIT/gFOBT, single and 5-yearly FS, and 10-yearly colonoscopy screening significantly reduces CRC-specific mortality. The model estimates are much higher than in RCTs, because the simulated biennial gFOBT assumes higher adherence. The effectiveness of screening increases at younger screening initiation ages and higher adherences.

Willingness to Undergo Gastroscopy for Early Gastric Cancer Screening and Its Associated Factors During the COVID-19 Pandemic - A Nationwide Cross-Sectional Study in China

PURPOSE

This study aimed to investigate the willingness of Chinese adults aged 40 years and older to undergo gastroscopy for gastric cancer (GC) screening during the COVID-19 pandemic in 2020. The secondary purpose was to identify factors influencing willingness to undergo gastroscopy.

METHODS

A cross-sectional questionnaire survey was conducted in selected cities and counties from nine provinces in China using a multi-stage sampling approach. A multivariate logistic regression model was used to determine the independent predictors of willingness to undergo gastroscopy.

RESULTS

This study included 1900 participants, and 1462 (76.95%) responded that they would undergo gastroscopy for GC screening. Participants of younger age, from the eastern region, living in an urban area, with higher educational levels, with Helicobacter pylori (H. pylori) infection, or with precancerous stomach lesions, were more willing to undergo gastroscopy. The top four reasons to reject gastroscopy were fear of pain or discomfort, worry about a possible devastating test result, no symptoms in self-feeling, and concern about the high expense. Of all those who would reject gastroscopy for GC screening, 36.76% (161/438) would be willing to accept painless gastroscopy, while 24.89% (109/438) would be willing to undergo gastroscopy screening if higher medical reimbursement rates were available. Participants considered that gastroscopy was a relatively fearful and unknown procedure, accompanied by high risks and benefits compared to all other life events.

CONCLUSION

In general, 76.95% of participants over 40 years old were willing to undergo gastroscopy for GC screening in China during the COVID-19 pandemic. Participants' willingness to undergo GC screening increased due to medical resource constraints and increased interest in their health. Individuals with H. pylori infection are more likely to undergo gastroscopy, whereas old age individuals, those with lower educational levels, and those living in rural areas are more likely to reject gastroscopy.

Can healthcare choice be predicted using stated preference data? The role of model complexity in a discrete choice experiment about colorectal cancer screening

INTRODUCTION

The validity of discrete choice experiments (DCEs) is crucial to its usage in healthcare decision-making, but there is only a limited number of health contexts in which external validity is demonstrated. This study aims to assess the internal and external validity of the DCE in the context of colorectal cancer (CRC) screening, and gather insights into the discrepancy between stated and revealed preferences.

METHODS

Stated and revealed preferences were elicited on an individual level from Dutch residents eligible for CRC screening in a DCE and a field experiment, respectively (N = 568). To identify the determinants of CRC screening participation and their relative importance, five random utility maximisation models that varied in complexity were used. We assessed the accuracy with which the models based on stated preferences predict individual-level screening choice in a holdout task (internal validity) and in the actual screening choice (external validity). Insights into the discrepancy between stated and revealed preferences were gathered by comparing groups of respondents.

RESULTS

Our findings show high internal and external validity. Choices could be accurately predicted for 95% of the respondents in the holdout task, and 90% in the actual screening choice. When scale and preference heterogeneity were taken into account model fit improved; individual-level prediction accuracy slightly increased for the holdout task but not for the actual screening choice. Respondents for whom stated preferences matched revealed preferences were generally in better health and found the GP's support for their screening decision more important.

DISCUSSION

Evidence was found that revealed preferences can be predicted accurately on an individual level. Incorporating heterogeneity improved internal validity but not external validity. Differences between stated and revealed preferences can be attributed to respondents' health and the support of their GP. We suggest researchers to continue investigating the internal and external validity of discrete choice experiments, and the role of model complexity.

Colorectal Cancer Survival Trends in the United States From 1992 to 2018 Differ Among Persons From Five Racial and Ethnic Groups According to Stage at Diagnosis: A SEER-Based Study

Introduction

Survival following colorectal cancer (CRC) has improved in the US since 1975, but there is limited information on stage-specific survival trends among racial and ethnic subgroups.

Objectives

The purpose of this study was to estimate and compare trends in 1- and 5-year CRC cause-specific survival in the United States by both stage and race/ethnicity.

Methods

We performed a retrospective cohort study of individuals diagnosed with CRC using the 1992-2018 Surveillance, Epidemiology and End Results (SEER) database. We estimated and compared time trends in 1- and 5-year survival for CRC stage by race/ethnicity.

Results

Data from 399 220 individuals diagnosed with CRC were available. There were significant differences in stage-specific 1-year survival trends by race and ethnicity. Differences were most notable for distant stage CRC: survival probabilities increased most consistently for non-Hispanic American Indian/Alaska Native (AIAN) and Black (NHB) persons, but their trend lines were lower than those of Hispanic, and non-Hispanic Asian/Pacific Islander (API) and White (NHW) persons, whose initially greater gains appear to be slowing. Although the data do not support significant racial/ethnic differences in 5-year CRC survival trends by stage, AIAN and NHB persons have the lowest average survival probabilities for multiple CRC stages, and no racial/ethnic group has 5-year survival probabilities above 20% for distant-stage CRC.

Conclusion

Although there has been an overall improvement in adjusted CRC-specific survival probabilities since 1992, AIAN and NHB persons continue to experience worse prognosis than those of other races/ethnicities. This highlights the importance of reinvigorating efforts to understand the causes of mortality in CRC, including those which may differ according to an individual’s race or ethnicity.

American Indian/Alaska Native and black colon cancer patients have poorer cause-specific survival based on disease stage and anatomic site of diagnosis

OBJECTIVES

Studies of race-specific colon cancer (CC) survival differences between right- vs. left-sided CC typically focus on Black and White persons and often consider all CC stages as one group. To more completely examine potential racial and ethnic disparities in side- and stage-specific survival, we evaluated 5-year CC cause-specific survival probabilities for five racial/ethnic groups by anatomic site (right or left colon) and stage (local, regional, distant).

METHODS

We obtained cause-specific survival probability estimates from National Cancer Institute's population-based Surveillance, Epidemiology, and End Results (SEER) for CC patients grouped by five racial/ethnic groups (Non-Hispanic American Indian/Alaska Native [AIAN], Non-Hispanic Asian/Pacific Islander [API], Hispanic, Non-Hispanic Black [NHB], and Non-Hispanic White [NHW]), anatomic site, stage, and other patient and SEER registry characteristics. We used meta-regression approaches to identify factors that explained differences in cause-specific survival.

RESULTS

Diagnoses of distant-stage CC were more common among NHB and AIAN persons (>22 %) than among NHW and API persons (< 20 %). Large disparities in anatomic site-specific survival were not apparent. Those with right-sided distant-stage CC had a one-year cause-specific survival probability that was 16.4 % points lower (99 % CI: 12.2-20.6) than those with left-sided distant-stage CC; this difference decreased over follow-up. Cause-specific survival probabilities were highest for API, and lowest for NHB, persons, though these differences varied substantially by stage at diagnosis. AIAN persons with localized-stage CC, and NHB persons with regional- and distant-stage CC, had significantly lower survival probabilities across follow-up.

CONCLUSIONS

There are differences in CC presentation according to anatomic site and disease stage among patients of distinct racial and ethnic backgrounds. This, coupled with the reality that there are persistent survival disparities, with NHB and AIAN persons experiencing worse prognosis, suggests that there are social or structural determinants of these disparities. Further research is needed to confirm whether these CC cause-specific survival disparities are due to differences in risk factors, screening patterns, cancer treatment, or surveillance, in order to overcome the existing differences in outcome.

Do Gastroenterologists Have a "Weak" Day? Impact of Day of the Week on the Quality of Outpatient Screening Colonoscopies

GOAL

The goal of this study is to determine the significance of day of the work week and its contribution to endoscopist performance using adenoma detection rate (ADR) and proposed surrogate quality measures.

BACKGROUND

Nearly a quarter of adenomas are missed on routine screening colonoscopy which contributes to between 50% and 60% of interval colorectal cancer.

MATERIALS AND METHODS

Adult patients who underwent outpatient screening colonoscopy between January 2015 and April 2020 were included. Measurement of ADR and proposed quality metrics were analyzed for each day of the work week. Secondary outcomes included rates of good or excellent bowel preparation, trainee fellow participation, performance quartile of individual endoscopists, and patient demographic data. A generalized linear mixed model was used to analyze predictors of ADR.

RESULTS

A total of 1884 screening procedures were included in our analysis. ADR on Friday (35.6%) was significantly lower than all other days of the work week ( P <0.001). When compared with Friday, all days were found to be independent predictors of increased ADR. Male gender [95% confidence interval (CI): 1.12-1.65, P =0.002], good rather than excellent bowel preparation (95% CI: 1.22-2.28, P =0.001) and colonoscopy withdrawal time (CWT) (95% CI: 1.02-1.03, P <0.001) were all found to be predictors of increased ADR. Proposed quality indicators were all well correlated with ADR ( r >0.811, P ≤0.001) apart from CWT ( r =0.28, P =0.379).

CONCLUSIONS

The data suggests there is a decline in endoscopist performance on Friday when compared with all other days of the work week. ADR correlates well with many proposed quality parameters, however, CWT may be of additional value as a quality metric.

Conceptual Model for the Hepatocellular Carcinoma Screening Continuum: Current Status and Research Agenda

Hepatocellular carcinoma (HCC) continues to have a dismal prognosis, with 5-year survival below 20%. This poor prognosis can be in part attributed to failures along the cancer screening process continuum such as underuse of screening in at risk patients and appropriate treatments for patients with HCC. Better understanding these process failures, and how they compare to those seen in other cancer types, can help inform potential intervention targets and strategies to reduce HCC-related mortality. Herein, we outline a conceptual model with several discrete steps in the HCC screening process continuum including risk assessment, screening initiation, follow-up of screening results, diagnostic evaluation, and treatment evaluation. The conceptual model illustrates how each step in the screening process is prone to delays or failure, resulting in worse outcomes such as late stage diagnosis or poor survival, and how factors at the patient, provider, and health care system levels can contribute to these failures. We compare cancer screening processes for HCC with those employed in breast and colorectal cancer screening to identify opportunities for improvement. The Translational Liver Cancer consortium was recently established by the National Cancer Institute with the goal of improving early detection of HCC. Studies designed to address failures in the HCC screening process continuum will help accomplish this goal.

Precision Medicine for Colorectal Cancer with Liquid Biopsy and Immunotherapy

Simple Summary

There are some challenges to improve the clinical outcome of colorectal cancers (CRCs) by implementing new technologies, such as early detection of recurrence/relapse and selection of appropriate drugs based on the genomic profiles of tumors. For example, the genomic characteristics of tumors can be analyzed by blood-based tests, namely ‘liquid biopsies’, which are minimally-invasive and can be performed repeatedly during the treatment course. Hence, liquid biopsies are considered to hold great promise to fill these gaps in clinical routines. In this review, we addressed clinical usefulness of liquid biopsies in the clinical management of CRC patients, including cancer screening, detection of minimal residual disease, selection of appropriate molecular-targeted drugs, monitoring of the treatment responsiveness, and very early detection of recurrence/relapse of the disease. Furthermore, we discussed the possibility of adoptive T cell therapies and a future personalized immunotherapy based on tumor genome information.

Abstract

In the field of colorectal cancer (CRC) treatment, diagnostic modalities and chemotherapy regimens have progressed remarkably in the last two decades. However, it is still difficult to identify minimal residual disease (MRD) necessary for early detection of recurrence/relapse of tumors and to select and provide appropriate drugs timely before a tumor becomes multi-drug-resistant and more aggressive. We consider the leveraging of in-depth genomic profiles of tumors as a significant breakthrough to further improve the overall prognosis of CRC patients. With the recent technological advances in methodologies and bioinformatics, the genomic profiles can be analyzed profoundly without delay by blood-based tests—‘liquid biopsies’. From a clinical point of view, a minimally-invasive liquid biopsy is thought to be a promising method and can be implemented in routine clinical settings in order to meet unmet clinical needs. In this review, we highlighted clinical usefulness of liquid biopsies in the clinical management of CRC patients, including cancer screening, detection of MRD, selection of appropriate molecular-targeted drugs, monitoring of the treatment responsiveness, and very early detection of recurrence/relapse of the disease. In addition, we addressed a possibility of adoptive T cell therapies and a future personalized immunotherapy based on tumor genome information.

Coprocytobiology: A Technical Review of Cytological Colorectal Cancer Screening in Fecal Samples

GRAPHICAL ABSTRACT

Korean colonoscopy screening pilot study (K-cospi) for screening colorectal cancer: study protocol for the multicenter, community-based clinical trial

BACKGROUND

The Korean National Cancer Screening Program has been providing annual fecal immunochemical test for colorectal cancer (CRC) to adults aged 50 years and older since 2004. The Korean Colonoscopy Screening Pilot Study was developed to evaluate the effectiveness of colonoscopy screening for CRC incidence and mortality, screening-related complications, and acceptability of colonoscopy as a primary modality for the national CRC screening program.

METHODS

This study and its protocols have been approved by the Korean Public Institutional Review Board and the National Cancer Center Institutional Review Board. We obtain written informed consent from all participants. The target population is males and females aged 50-74 years living within the pilot sites. A total of 26,640 participants will be recruited for colonoscopy screening. Subjects who have been diagnosed with CRC, who are currently undergoing treatment for CRC, or who have undergone colonoscopy screening within the past 5 years are not allowed to participate. All participants need to complete baseline questionnaires. This pilot study is currently conducted by 104 endoscopists from 57 national cancer screening institutions (42 primary, 10 secondary, and 5 tertiary institutions) located in Goyang-si, Gimpo-si, and Paju-si. The number of endoscopists, medical institutions, and districts participating in the pilot study will be expanded, if necessary. Participating endoscopists at each medical institution perform colonoscopy and report the colonoscopy results to a centralized electronic case report system. We conduct a telephone survey after 7 days and 4 weeks post-colonoscopy to assess for procedure-related complications and satisfaction of the participants. In case of abnormal findings from colonoscopy screening, we track the results from follow-up diagnostic tests. Data from this pilot study will be linked to the diagnostic workup results, the Korean Cancer Registry, and death certificate data for analysis of the performance, long-term effects, and cost-effectiveness of colonoscopy.

DISCUSSION

The results will provide critical information to determine whether the introduction of colonoscopy as the primary modality of the Korean National Cancer Screening Program would be acceptable and feasible. Trial registration Korean Clinical Research Information Service registry, KCT0004142. Registered on 15 July 2019, http://cris.nih.go.kr/cris/en/search/search_result_st01.jsp?seq=16227.

The health belief model and colorectal cancer screening in the general population: A systematic review

Colorectal cancer screening saves lives and is cost-effective. It allows early detection of the pathology, and enables earlier medical intervention. Despite clinical practice guidelines promoting screening for average risk individuals, uptake remains suboptimal in many populations. Few studies have examined how sociobehavioural factors influence screening uptake in the context of behaviour change theories such as the health belief model. This systematic review therefore examines how the health belief model’s constructs are associated with colorectal cancer screening.

Four databases were systematically searched from inception to September 2019. Quantitative observational studies that used the health belief model to examine colorectal screening history, intention or behaviour were included.

A total of 30 studies met the criteria for review; all were of cross-sectional design. Perceived susceptibility, benefits and cues to action were directly associated with screening history or intention. Perceived barriers inversely associated with screening history or intention. The studies included also found other modifying factors including sociodemographic and cultural norms. Self-report of screening history, intention or behaviour, convenience sampling and lack of temporality among factors were common limitations across studies.

The health belief model’s associations with colorectal cancer screening uptake was consistent with preventive health behaviours in general. Future studies should examine how theory-based behavioural interventions can be tailored to account for the influence of socioecological factors.

Efficacy and safety of acupuncture and moxibustion for herpes zoster: A protocol for systematic review and network meta analysis

INTRODUCTION

Herpes zoster (HZ) is currently treated primarily with antiviral drugs, yet this treatment has been debated. Acupuncture is becoming a more important treatment in this protocol. For example, pain intensity is lower among HZ patients who receive acupuncture plus moxibustion than among those who receive pharmacotherapy. There are many types of acupuncture interventions, including electroacupuncture, moxibustion, bloodletting. In this study, a network meta-analysis (NMA) is used to rank various interventions of acupuncture.

METHODS AND ANALYSIS

Electronic searches of abstracts and titles will be performed in MEDLINE, EMBASE, CENTRAL, CBM, CNKI, CQVIP, and Wanfang Data databases, from inception to December 31, 2019. Published and unpublished controlled trials with different acupuncture interventions will be selected, trials of antiviral drugs as the control group. All patients of HZ will be included, except for those diagnosed with PHN, immunocompromised patients, or those with complications. The effective therapy rate and the incidence of PHN are primary outcomes. The NMA will be analyzed with Stata 13.0 and GeMTC 0.14.3.

DISCUSSION

The NMA will be established to compare various interventions of acupuncture for the therapy of HZ, that could resolve the limitations of previous methodologies with this protocol. It will be possible to determine the best acupuncture intervention for more primary outcomes of therapy, including subgroup analysis of patients with aged ≥50 years and those of aged <50 years.

ETHICS AND DISSEMINATION

The NMA does not require ethical approval. The data analyzed is not personal. It is only systematically used to evaluate the effectiveness of acupuncture treatments. The results will be disseminated through international conference reports and peer-reviewed manuscripts.

STRENGTH AND LIMITATIONS OF THIS STUDY

A comprehensive methodology is established to rank various interventions of acupuncture by which best evidence-based intervention may be recommended for those population groups of aged ≥50 years and aged <50 years.

PROSPERO REGISTRATION NUMBER

CRD42019118369.

Colorectal Cancer Survival in 50- to 69-Year-Olds after Introducing the Faecal Immunochemical Test

Population screening has improved early diagnosis of colorectal cancer (CRC). Nonetheless, most cases are diagnosed in symptomatic patients. Faecal immunochemical testing has been recommended for assessing patients with lower gastrointestinal symptoms, but whether it improves patient survival is unknown. Our objective was to compare CRC survival in 50- to 69-year-olds between asymptomatic screen-detected patients and symptomatic patients by route to diagnosis. Methods: We identified all cases of CRC diagnosed in 50-to 69-year-olds between 2009 and 2016, in Donostialdea (Gipuzkoa, Spain). Three groups were created: 1-screen-detected CRC; 2-CRC detected in symptomatic patients after a positive faecal immunochemical test(FIT); and 3-CRC detected in symptomatic patients without a FIT or after a negative result. We analysed survival using the Kaplan-Meier method and log-rank tests. Results: Of 930 patients diagnosed with CRC, 433 cases were detected through screening and 497 in symptomatic patients, 7.9% after a positive FIT and 45.5% by other means. The 3-year CRC survival was significantly lower in group 3 (69.5%) than groups 1 (93%; p = 0.007) or 2 (87.5%; p = 0.02). The risk of death was lower in groups 1 (HR 0.42, 95% CI 0.30–0.58) and 2 (HR 0.51; 95% CI 0.29–0.87). Conclusion: Half of CRC cases in 50- to 69-year-olds are diagnosed outside screening. Use of the FIT as a diagnostic strategy in symptomatic patients may improve survival.

Colorectal Cancer Screening Decisions in the Opportunistic Setting

Colorectal cancer incidence and mortality have decreased in the United States in recent decades, largely through opportunistic screening. Although certain organizations have improved internal screening rates by implementing programmatic screening, most of the United States undergoes opportunistic screening. Much effort and resources have been expended comparing screening tests to determine the most effective; however, deeper analysis of the US population has revealed subsets of ethnicities may be grossly underscreened. The most effective screening test remains the test that is completed and adhered to, and a better question may concern the best method of discussing screening.

Adherence to national guidelines for colorectal cancer screening in Israel: Comprehensive multi-year assessment based on electronic medical records

OBJECTIVES

To assess time trends in colorectal cancer screening uptake, time-to-colonoscopy completion following a positive fecal occult blood test and associated patient factors, and the extent and predictors of longitudinal screening adherence in Israel.

SETTING

Nation-wide population-based study using data collected from four health maintenance organizations for the Quality Indicators in Community Healthcare Program.

METHODS

Screening uptake for the eligible population (aged 50-74) was recorded 2003-2018 using aggregate data. For a subcohort (2008-2012, N = 1,342,617), time-to-colonoscopy following a positive fecal occult blood test and longitudinal adherence to screening guidelines were measured using individual-level data, and associated factors assessed in multivariate models.

RESULTS

The annual proportion screened rose for both sexes from 11 to 65%, increasing five-fold for age group 60-74 and >six-fold for 50-59 year olds, respectively. From 2008 to 2012, 67,314 adults had a positive fecal occult blood test, of whom 71% eventually performed a colonoscopy after a median interval of 122 (95% confidence interval 110.2-113.7) days. Factors associated with time-to-colonoscopy included age, socioeconomic status, and comorbidities. Only 25.5% of the population demonstrated full longitudinal screening adherence, mainly attributable to colonoscopy in the past 10 years rather than annual fecal occult blood test performance (83% versus 17%, respectively). Smoking, diabetes, lower socioeconomic status, cardiovascular disease, and hypertension were associated with decreased adherence. Performance of other cancer screening tests and frequent primary care visits were strongly associated with adherence.

CONCLUSIONS

Despite substantial improvement in colorectal cancer screening uptake on a population level, individual-level data uncovered gaps in colonoscopy completion after a positive fecal occult blood test and in longitudinal adherence to screening, which should be addressed using focused interventions.

A novel artificial intelligence system for the assessment of bowel preparation (with video)

BACKGROUND AND AIMS

The quality of bowel preparation is an important factor that can affect the effectiveness of a colonoscopy. Several tools, such as the Boston Bowel Preparation Scale (BBPS) and Ottawa Bowel Preparation Scale, have been developed to evaluate bowel preparation. However, understanding the differences between evaluation methods and consistently applying them can be challenging for endoscopists. There are also subjective biases and differences among endoscopists. Therefore, this study aimed to develop a novel, objective, and stable method for the assessment of bowel preparation through artificial intelligence.

METHODS

We used a deep convolutional neural network to develop this novel system. First, we retrospectively collected colonoscopy images to train the system and then compared its performance with endoscopists via a human-machine contest. Then, we applied this model to colonoscopy videos and developed a system named ENDOANGEL to provide bowel preparation scores every 30 seconds and to show the cumulative ratio of frames for each score during the withdrawal phase of the colonoscopy.

RESULTS

ENDOANGEL achieved 93.33% accuracy in the human-machine contest with 120 images, which was better than that of all endoscopists. Moreover, ENDOANGEL achieved 80.00% accuracy among 100 images with bubbles. In 20 colonoscopy videos, accuracy was 89.04%, and ENDOANGEL continuously showed the accumulated percentage of the images for different BBPS scores during the withdrawal phase and prompted us for bowel preparation scores every 30 seconds.

CONCLUSIONS

We provided a novel and more accurate evaluation method for bowel preparation and developed an objective and stable system-ENDOANGEL-that could be applied reliably and steadily in clinical settings.

Evidence for reducing cancer-specific mortality due to screening for breast cancer in Europe: A systematic review

BACKGROUND

The aim of this study was to quantify the impact of organised mammography screening on breast cancer mortality across European regions. Therefore, a systematic review was performed including different types of studies from all European regions and stringently used clearly defined quality appraisal to summarise the best evidence.

METHODS

Six databases were searched including Embase, Medline and Web of Science from inception to March 2018. To identify all eligible studies which assessed the effect of organised screening on breast cancer mortality, two reviewers independently applied predefined inclusion and exclusion criteria. Original studies in English with a minimum follow-up of five years that were randomised controlled trials (RCTs) or observational studies were included. The Cochrane risk of bias instrument and the Newcastle-Ottawa Scale were used to assess the risk of bias.

RESULTS

Of the 5015 references initially retrieved, 60 were included in the final analysis. Those comprised 36 cohort studies, 17 case-control studies and 7 RCTs. None were from Eastern Europe. The quality of the included studies varied: Nineteen of these studies were of very good or good quality. Of those, the reduction in breast cancer mortality in attenders versus non-attenders ranged between 33% and 43% (Northern Europe), 43%-45% (Southern Europe) and 12%-58% (Western Europe). The estimates ranged between 4% and 31% in invited versus non-invited.

CONCLUSION

This systematic review provides evidence that organised screening reduces breast cancer mortality in all European regions where screening was implemented and monitored, while quantification is still lacking for Eastern Europe. The wide range of estimates indicates large differences in the evaluation designs between studies, rather than in the effectiveness of screening.

Impact of a Clinical Decision Support System on Guideline Adherence of Surveillance Recommendations for Colonoscopy After Polypectomy

Background: Surveillance colonoscopy is required in patients with polyps due to an elevated colorectal cancer (CRC) risk; however, studies suggest substantial overuse and underuse of surveillance colonoscopy. The goal of this study was to characterize guideline adherence of surveillance recommendations after implementation of an electronic medical record (EMR)-based Colonoscopy Pathology Reporting and Clinical Decision Support System (CoRS). Methods: We performed a retrospective cohort study of patients who underwent colonoscopy with polypectomy at a safety-net healthcare system before (n=1,822) and after (n=1,320) implementation of CoRS in December 2013. Recommendations were classified as guideline-adherent or nonadherent according to the US Multi-Society Task Force on CRC. We defined surveillance recommendations shorter and longer than guideline recommendations as potential overuse and underuse, respectively. We used multivariable generalized linear mixed models to identify correlates of guideline-adherent recommendations. Results: The proportion of guideline-adherent surveillance recommendations was significantly higher post-CoRS than pre-CoRS (84.6% vs 77.4%; P<.001), with fewer recommendations for potential overuse and underuse. In the post-CoRS period, CoRS was used for 89.8% of cases and, compared with cases for which it was not used, was associated with a higher proportion of guideline-adherent recommendations (87.0% vs 63.4%; RR, 1.34; 95% CI, 1.23-1.42). In multivariable analysis, surveillance recommendations were also more likely to be guideline-adherent in patients with adenomas but less likely among those with fair bowel preparation and those with family history of CRC. Of 203 nonadherent recommendations, 70.4% were considered potential overuse, 20.2% potential underuse, and 9.4% were not provided surveillance recommendations. Conclusions: An EMR-based CoRS was widely used and significantly improved guideline adherence of surveillance recommendations.

Community-Clinical Linkage Intervention to Improve Colorectal Cancer Screening Among Underserved Korean Americans

Korean Americans report the lowest and declined rates of colorectal cancer (CRC) screening, compared to general population in the United States. The present study aimed to evaluate the efficacy of a community-based multifaceted intervention designed to improve CRC screening among Korean Americans. A cluster-randomized trial involving 30 Korean church-based community organizations (n = 925) was conducted. Fifteen churches were assigned to intervention (n=470) and the other 15 to control (n = 455) groups. Main components of the intervention included interactive group education, patient navigation, physician engagement, and provision of fecal immunochemical test (FIT) kit. CRC screening rates were assessed at a 12-month follow-up. Participants in the intervention group were significantly more likely to receive CRC screening (69.3%) as compared with those in the control group (16%). The intervention was particularly effective in promoting FIT among the more disadvantaged individuals in the Korean American community. Regression analysis revealed that controlling for the intervention effect, male gender, high school education, annual income of $20,000-40,000 were significantly associated with increased screening by FIT, whereas English inefficiency was significantly and lack of health insurance was marginally significantly associated with decreased screening by colonoscopy/sigmoidoscopy. Culturally and linguistically appropriate multifaceted intervention combining FIT provision with community-clinical linkage has a potential to be a cost-effective and practical approach to effectively targeting hard-to-reach disadvantaged minority populations and enhance CRC screening to reduce cancer disparities.

Patterns and predictors of repeat fecal immunochemical and occult blood test screening in four large health care systems in the United States

OBJECTIVES

Effectiveness of fecal occult blood test (FOBT) for colorectal cancer (CRC) screening depends on annual testing, but little is known about patterns of repeat stool-based screening within different settings. Our study's objective was to characterize screening patterns and identify factors associated with repeat screening among patients who completed an index guaiac FOBT (gFOBT) or fecal immunochemical test (FIT).

METHODS

We performed a multi-center retrospective cohort study among people who completed a FOBT between January 2010 and December 2011 to characterize repeat screening patterns over the subsequent 3 years. We studied at 4 large health care delivery systems in the United States. Logistic regression analyses were used to identify factors associated with repeat screening patterns. We included individuals aged 50-71 years who completed an index FOBT and had at least 3 years of follow-up. We excluded people with a history of CRC, colonoscopy within 10 years or flexible sigmoidoscopy within 5 years before the index test, or positive index stool test. Consistent screening was defined as repeat FOBT within every 15 months and inconsistent screening as repeat testing at least once during follow-up but less than consistent screening.

RESULTS

Among 959,857 eligible patients who completed an index FIT or gFOBT, 344,103 had three years of follow-up and met inclusion criteria. Of these, 46.6% had consistent screening, 43.4% inconsistent screening, and 10% had no repeat screening during follow-up. Screening patterns varied substantially across healthcare systems, with consistent screening proportions ranging from 1 to 54.3% and no repeat screening proportions ranging from 6.9 to 42.8%. Higher consistent screening proportions were observed in health systems with screening outreach and in-reach programs, whereas the safety-net health system, which uses opportunistic clinic-based screening, had the lowest consistent screening. Consistent screening increased with older age but was less common among racial/ethnic minorities and patients with more comorbidities.

CONCLUSIONS

Adherence with annual FOBT screening is highly variable across healthcare delivery systems. Settings with more organized screening programs performed better than those with opportunistic screening, but evidence-based interventions are needed to improve CRC screening adherence in all settings.

Geographic variation in the provider of screening colonoscopy in Canada: a population-based cohort study

BACKGROUND

Screening colonoscopy for the detection of colorectal carcinoma is provided by several specialties. Few studies have assessed geographic variation in the delivery of this care. Our objective was to investigate how geographic and socioeconomic factors affect who provides screening colonoscopy in Canada.

METHODS

This was a population-based cohort of all screening colonoscopy procedures performed at publicly funded Canadian health care facilities (excluding those in Quebec) between April 2008 and March 2015. The main outcome of interest was the proportion of colonoscopy procedures performed by surgeons versus gastroenterologists at the neighbourhood level. Predictors of interest included socioeconomic and geographic variables. We used spatial analysis to evaluate significant clustering of practitioner services and multinomial logistic regression to model predictors.

RESULTS

We identified 658 113 screening colonoscopy procedures performed by 1886 providers (1169 surgeons and 717 gastroenterologists) over the study period, of which 353 165 (53.7%) were performed by surgeons. A total of 24.2% of neighbourhoods were located within clusters predominantly served by gastroenterologists, and 19.5% were within surgeon clusters; the remainder were in mixed clusters. Rural neighbourhoods had a significantly increased relative risk of being within a surgeon cluster (relative risk [RR] 5.38, 95% confidence interval [CI] 3.48-8.01) compared to mixed clusters and nearly 100 times higher relative risk of being in a surgeon cluster compared to gastroenterologist clusters (RR 98.95, 95% CI 15.3-427.2). Neighbourhoods with the highest socioeconomic status were 1.74 (95% CI 1.14-2.56) times likelier to be in gastroenterologist clusters than in mixed clusters.

INTERPRETATION

Surgeons provide a large proportion of colonoscopy procedures in Canada and are essential for access to care, particularly in rural regions. Most Canadians are served relatively equally by surgeons and gastroenterologists. This emphasizes the importance of both specialties to the delivery of colonoscopy care across the country.

Inadequate Boston Bowel Preparation Scale scores predict the risk of missed neoplasia on the next colonoscopy

BACKGROUND AND AIMS

The risks of missed findings after inadequate bowel preparation are not fully characterized in a diverse cohort. We aimed to evaluate the likelihood of missed polyps after an inadequate preparation as assessed by using the Boston Bowel Preparation Scale (BBPS).

METHODS

In this observational study of prospectively collected data within a large, national, endoscopic consortium, we identified patients aged 50 to 75 years who underwent average-risk screening colonoscopy (C1) followed by a second colonoscopy for any indication within 3 years (C2). We determined the polyp detection rates (PDRs) and advanced PDRs during C2 stratified by C1 BBPS scores.

RESULTS

Among segment pairs without polyps at C1 (N = 601), those with inadequate C1 BBPS segment scores had a higher PDR at C2 (10%) compared with those with adequate bowel preparation at C1 (5%; P = .04). Among segment pairs with polyps at C1 (N = 154), segments with inadequate bowel preparation scores at C1 had higher advanced PDRs at C2 (20%) compared with those with adequate bowel preparation scores at C1 (4%; P = .03). In multivariable analysis, the presence of advanced polyps at C1 (adjusted odds ratio [OR] 3.5; 95% confidence intervals [CIs], 1.1-10.8) but not inadequate BBPS scores at C1 (adjusted OR 1.8; 95% CI, 0.6-5.1) was associated with a significantly increased risk of advanced polyps at C2.

CONCLUSIONS

Inadequate BBPS segment scores generally are associated with higher rates of polyps and advanced polyps at subsequent colonoscopy within a short timeframe. The presence of advanced polyps as well as inadequate BBPS segment scores can inform the risk of missed polyps and help triage which patients warrant a timely repeat colonoscopy.

Public health impact of colonoscopy use on colorectal cancer mortality in Germany and the United States

BACKGROUND AND AIMS

Colonoscopy has been demonstrated to be effective in reducing colorectal cancer (CRC) incidence and mortality and has been widely used for primary CRC screening in Germany and the United States. We performed a population-based analysis to evaluate and compare the public health impact of recent colonoscopy use on CRC deaths among adults aged 55 to 79 years in Germany and the United States from 2008 to 2011.

METHODS

The epidemiologic metrics of attributable fraction and prevented fraction as well as the impact numbers were calculated using colonoscopy utilization data from nationally representative health surveys, relative risk estimates from medical literature, and CRC death registry data.

RESULTS

Overall, 36.6% (95% credible interval [CrI], 27.3%-45.5%) of CRC deaths in Germany were estimated to be attributable to nonuse of colonoscopy, compared with the U.S. estimates of 38.2% (95% CrI, 28.6%-47.1%) and 33.6% (95% CrI, 24.8%-42.2%) for years 2008 to 2009 and 2010 to 2011, respectively. The proportion of CRC deaths theoretically prevented by colonoscopy use within 10 years was 30.7% (95% CrI, 24.8%-35.7%) in Germany, whereas in the United States this proportion ranged from 29.0% (95% CrI, 23.4%-33.6%) for 2008 to 2009 to 33.9% (95% CrI, 27.4%-39.2%) for 2010 to 2011.

CONCLUSIONS

Recent colonoscopy use is likely to have prevented a considerable fraction of CRC mortality in both countries, and more deaths could be avoided by increasing colonoscopy use in the target population. Attributable and prevented fraction can provide valuable information on the public health impact of colonoscopy use and guide policymaking.

Hepatocellular Carcinoma Surveillance Among Patients With Cirrhosis in a Population-based Integrated Health Care Delivery System

PURPOSE

Fewer than 1 in 5 patients with cirrhosis receive hepatocellular carcinoma (HCC) surveillance; however, most studies were performed in select patient populations, which may not be informative of practice patterns in population-based community practices. Further, few reported guideline-concordant consistent surveillance rates.

GOALS

Characterize guideline-concordant HCC surveillance rates and patient-level factors associated with surveillance among a population-based cohort of patients with cirrhosis.

STUDY

We retrospectively characterized HCC surveillance among cirrhosis patients followed between January 2010 and December 2012 at an integrated health care delivery system in Washington state. Consistent surveillance was defined as an ultrasound every 6 months, and inconsistent surveillance was defined as ≥1 ultrasound during the 2-year follow-up period. Univariate and multivariate analyses were conducted to identify correlates of HCC surveillance receipt.

RESULTS

Of 1137 patients with cirrhosis, 22 (2%) underwent consistent surveillance, 371 (33%) had inconsistent surveillance, and 744 (65%) received no surveillance during follow-up. Correlates of HCC surveillance receipt in multivariate analysis included Gastroenterology/Hepatology subspecialty care [odds ratio (OR), 1.88; 95% confidence interval (CI), 1.44-2.46], Child Pugh B/C cirrhosis (OR, 1.61; 95% CI, 1.07-2.43), elevated aspartate aminotransferase (OR, 1.63; 95% CI, 1.13-2.35), and etiology of liver disease. Compared with hepatitis C-infected patients, patients with hepatitis B infection were more likely to undergo surveillance (OR, 2.72; 95% CI, 1.28-5.81), whereas patients with alcohol-related cirrhosis (OR, 0.63; 95% CI, 0.42-0.93) and nonalcoholic steatohepatitis (OR, 0.39; 95% CI, 0.28-0.56) were less likely to undergo surveillance.

CONCLUSIONS

Although one third of patients undergo inconsistent HCC surveillance, <2% of patients receive guideline-concordant biannual HCC surveillance.

Effectiveness of Screening Modalities in Colorectal Cancer: A Network Meta-Analysis

The aim of the study was to evaluate on the effectiveness of screening modalities in the prevention of colorectal cancer (CRC) occurrence and deaths. General meta-analysis was performed to produce pooled estimates of the effect of CRC incidence and mortality using a search of PubMed, Web of Science, and the Cochrane Library for eligible studies from January 1992 to March 2016. A network meta-analysis was performed to synthetically compare the effectiveness of 5 frequently used screening modalities. A total of 44 studies with a focus on mortality from CRC using different screening methods were included. General meta-analysis showed that fecal immunohistochemical testing (FIT), flexible sigmoidoscopy (FS), colonoscopy, combination of fecal occult blood testing and FS screening respectively reduced CRC mortality by 59% (relative risk [RR], 0.41; 95% confidence interval [CI], 0.29-0.59), 33% (RR, 0.67; 95% CI, 0.58-0.78), 61% (RR, 0.39; 95% CI, 0.31-0.50), 38% (RR, 0.62; 95% CI, 0.42-0.91) compared with no screening, whereas guaiac fecal occult blood testing (gFOBT) reduced CRC-related mortality by 14% (RR, 0.86; 95% CI, 0.82-0.90). Subgroup analysis showed that summary estimates of reduction in distal CRC mortality and proximal CRC mortality were 26% (95% CI, 62%-89%) and 10% (95% CI, 83%-98%). A network meta-analysis revealed rank probability analysis in which the colonoscopy had a 94.6% probability of being the most effective examination to reduce CRC mortality. In addition, the network meta-analysis estimated odds ratio, which was a 79% reduction (95% CI, 0.09-0.60) in CRC mortality when screening with FIT was compared with annual or biennial gFOBT and colonoscopy was approximately 80% more effective than gFOBT for reducing CRC mortality (RR, 0.25; 95% CI, 0.13-0.54). Analysis of the effects of different screening methods showed that there was a significant reduction in the incidence of colon cancer, excluding gFOBT. This meta-analysis confirmed that gFOBT, FIT, FS, and colonoscopy were all effective in preventing CRC deaths and a major reduction in distal but not proximal CRC mortality was found. In addition, they were more effective in preventing CRC incidence in addition to gFOBT. The network meta-analysis suggests that colonoscopy is the most effective screening for preventing CRC deaths.

Reasons for Lack of Diagnostic Colonoscopy After Positive Result on Fecal Immunochemical Test in a Safety-Net Health System

BACKGROUND

Effective colorectal cancer screening depends on timely diagnostic evaluation in patients with abnormal results on fecal immunochemical tests (FITs). Although prior studies suggest low rates of follow-up colonoscopy, there is little information among patients in safety-net health systems and few data characterizing reasons for low follow-up rates. This study aimed to characterize factors contributing to lack of follow-up colonoscopy in a racially diverse and socioeconomically disadvantaged cohort of patients with abnormal results on FIT ("abnormal FIT" for brevity) receiving care in an integrated safety-net health system.

METHODS

We performed a retrospective electronic medical record review of patients aged 50-64 years with abnormal FIT at a population-based safety-net health system between January 2010 and July 2013. Review of electronic medical records focused on patients without follow-up colonoscopy to characterize patient-, provider-, and system-level reasons for lack of diagnostic evaluation. We used logistic regression analysis to identify predictors of follow-up colonoscopy within 12 months of abnormal FIT.

RESULTS

Of 1267 patients with abnormal FIT, 536 (42.3%) failed to undergo follow-up colonoscopy within 1 year. Failure was attributable to patient-level factors in 307 (57%) cases, provider factors in 97 (18%) cases, and system factors in 118 (22%) cases. In multivariate analysis, follow-up colonoscopy was less likely among those aged 61-64 years (odds ratio 0.63, 95% confidence interval 0.46-0.87) compared with 50-55 year olds.

CONCLUSIONS

Nearly half (42%) of patients with abnormal FIT failed to undergo follow-up colonoscopy within 1 year. Lack of diagnostic evaluation is related to a combination of patient-, provider-, and system-level factors, highlighting the need for multilevel interventions to improve follow-up colonoscopy completion rates.

Osteoprotegerin: A novel biomarker for inflammatory bowel disease and gastrointestinal carcinoma

Osteoprotegerin (OPG) is a member of the tumor necrosis factor receptor superfamily of proteins. Although initial data illustrated the key role that OPG plays in bone turnover, numerous recent reports indicate that OPG is also an important factor in inflammatory pathways and tumor cell survival. OPG contributes directly to inflammatory processes and has been evaluated as a novel non-invasive biomarker of gut inflammation. Furthermore, OPG affects cell turn-over, differentiation, death, and survival via extracellular pathways, correlating with worse prognosis in inflammatory bowel diseases and several gastrointestinal carcinomas. It is now clear that OPG has multiple functions and characteristics. This review gives an overview of OPG, highlights its roles in different extracellular pathways, and outlines how OPG could be used as a novel non-invasive biological marker in inflammatory bowel diseases and gastrointestinal carcinomas.

Meta-Analysis of the Effect of Bowel Preparation on Adenoma Detection: Early Adenomas Affected Stronger than Advanced Adenomas

Background and Aims

Low-quality bowel preparation reduces efficacy of colonoscopy. We aimed to summarize effects of bowel preparation on detection of adenomas, advanced adenomas and colorectal cancer.

Methods

A systematic literature search was performed regarding detection of colonic lesions after normal and low-quality bowel preparation. Reported bowel preparation quality was transformed to the Aronchick scale with its qualities “excellent”, “good”, “fair”, “poor”, and “insufficient” or “optimal” (good/excellent), “suboptimal” (fair/poor/insufficient), “adequate” (good/excellent/fair) and “inadequate” (poor/insufficient). We identified two types of studies: i) Comparative studies, directly comparing lesion detection according to bowel preparation quality, and ii) repeat colonoscopy studies, reporting results of a second colonoscopy after previous low-quality preparation.

Results

The detection of early adenomas was reduced with inadequate vs. adequate bowel preparation (Odds Ratio (OR) 0.53, CI: 0.46–0.62, p<0.001). The advanced adenomas were affected less in comparison (0.74, CI: 0.62–0.87, p<0.001). The large number of subjects considered in the present meta-analysis resulted in smaller confidence intervals compared to earlier studies. Classifying the bowel-preparation quality as suboptimal vs. optimal led to the same qualitative conclusion (OR: 0.81, CI: 0.74–0.89, p<0.001 for early adenomas, OR: 0.94, CI: 0.87–1.01, n.s. for advanced adenomas). Bowel preparation was equally important for right-sided/ flat/ serrated vs. other lesions in most observational studies but more relevant in some repeat colonoscopy studies; data regarding carcinoma detection were insufficient.

Conclusion

Inadequate bowel preparation affects detection of early colonic lesions stronger than advanced lesions.

Colonoscopy Reduces Colorectal Cancer Incidence and Mortality in Patients With Non-Malignant Findings: A Meta-Analysis

OBJECTIVES

Observational studies have shown that colonoscopy reduces colorectal cancer (CRC) incidence and mortality in the general population. We aimed to conduct a meta-analysis quantifying the magnitude of protection by colonoscopy, with screening and diagnostic indications, against CRC in patients with non-malignant findings and demonstrating the potentially more marked effect of screening over diagnostic colonoscopy.

METHODS

PubMed, EMBASE, and conference abstracts were searched through 30 April 2015. The primary outcomes were overall CRC incidence and mortality. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated using random-effect models.

RESULTS

Eleven observational studies with a total of 1,499,521 individuals were included. Pooled analysis showed that colonoscopy was associated with a 61% RR reduction in CRC incidence (RR: 0.39; 95% CI: 0.26-0.60; I(2)=93.6%) and a 61% reduction in CRC mortality (RR: 0.39; 95% CI: 0.35-0.43; I(2)=12.0%) in patients with non-malignant findings, although there was high heterogeneity for the outcome of CRC incidence. After excluding one outlier study, there was low heterogeneity for the outcome of incidence (I(2)=44.7%). Subgroup analysis showed that the effect of screening colonoscopy was more prominent, corresponding to an 89% reduction in CRC incidence (RR: 0.11; 95% CI: 0.08-0.15), in comparison with settings involving diagnostic colonoscopy (RR: 0.51; 95% CI: 0.43-0.59; P<0.001).

CONCLUSIONS

On the basis of this meta-analysis of observational studies, CRC incidence and mortality in patients with non-malignant findings are significantly reduced after colonoscopy. The effect of screening colonoscopy on CRC incidence is more marked than diagnostic colonoscopy.

Screening Coverage Needed to Reduce Mortality from Prostate Cancer: A Living Systematic Review

INTRODUCTION

Screening for prostate cancer remains controversial because of conflicting results from the two major trials: The Prostate, Lung, Colorectal and Ovarian Cancer (PLCO) screening trial and the European Randomized Study of Screening for Prostate Cancer (ERSPC).

OBJECTIVE

Meta-analyze and meta-regress the available PSA screening trials.

METHODS

We performed a living systematic review and meta-regression of the reduction in prostate cancer mortality as a function of the duration of screening provided in each trial. We searched PubMed, Web of Science, the Cochrane Registry, and references lists from previous meta-analyses to identify randomized trials of PSA screening. We followed PRISMA guidelines and qualified strength of evidence with a GRADE Profile.

RESULTS

We found 6 trials, but excluded one that also screened with trans-rectal ultrasound. We considered each ERSPC center as a separate trial. When pooling together all 11 trials we found no significant benefit from screening; however, the heterogeneity was 28.2% (95% CI: 0% to 65%). Heterogeneity was explained by variations in the duration of serial screening (I2 0%; 95% CI: 0% to 52%). When we analyzed the subgroup of trials that added more than 3 years of screening (range 3.2 to 3.8) we found a significant benefit for screening with risk ratio 0.78 (95% CI 0.65-0.94; I2 = 0%; 95% CI: 0% to 69%) and a number needed to invite for screening of 1000. We downgraded the quality of evidence to moderate due to our retrospective identification of subgroups and limited data on control group screening.

CONCLUSIONS

Adequate duration of screening reduces mortality from prostate cancer. The benefit, while small, compares favorably with screening for other cancers. Our projections are limited by the moderate quality of evidence.

Outreach invitations for FIT and colonoscopy improve colorectal cancer screening rates: A randomized controlled trial in a safety-net health system

BACKGROUND

The effectiveness of colorectal cancer (CRC) screening is limited by underuse, particularly among underserved populations. Among a racially diverse and socioeconomically disadvantaged cohort of patients, the authors compared the effectiveness of fecal immunochemical test (FIT) outreach and colonoscopy outreach to increase screening participation rates, compared with usual visit-based care.

METHODS

Patients aged 50 to 64 years who were not up-to-date with CRC screening but used primary care services in a large safety-net health system were randomly assigned to mailed FIT outreach (2400 patients), mailed colonoscopy outreach (2400 patients), or usual care with opportunistic visit-based screening (1199 patients). Patients who did not respond to outreach invitations within 2 weeks received follow-up telephone reminders. The primary outcome was CRC screening completion within 12 months after randomization.

RESULTS

Baseline patient characteristics across the 3 groups were similar. Using intention-to-screen analysis, screening participation rates were higher for FIT outreach (58.8%) and colonoscopy outreach (42.4%) than usual care (29.6%) (P <.001 for both). Screening participation with FIT outreach was higher than that for colonoscopy outreach (P <.001). Among responders, FIT outreach had a higher percentage of patients who responded before reminders (59.0% vs 29.7%; P <.001). Nearly one-half of patients in the colonoscopy outreach group crossed over to complete FIT via usual care, whereas <5% of patients in the FIT outreach group underwent usual-care colonoscopy.

CONCLUSIONS

Mailed outreach invitations appear to significantly increase CRC screening rates among underserved populations. In the current study, FIT-based outreach was found to be more effective than colonoscopy-based outreach to increase 1-time screening participation. Studies with longer follow-up are needed to compare the effectiveness of outreach strategies for promoting completion of the entire screening process.

Hepatocellular Carcinoma From Epidemiology to Prevention: Translating Knowledge into Practice

The epidemiology of hepatocellular carcinoma (HCC) is characterized by dynamic temporal trends, several major established (i.e., HCV, HBV, alcohol) and emerging (i.e., diabetes, obesity, NAFLD) risk factors. Epidemiologic studies and clinical trials have identified additional demographic, clinical, pharmacological, genetic and life style factors that further affect or modify the likelihood of HCC and can be used in clinical practice to identify at-risk patients (i.e., risk stratification or prognostic algorithms) that can be targeted for prevention and early detection programs. These studies have also paved the way toward several well established preventive measures including HBV vaccination, HBV treatment, HCV treatment and HCC surveillance, and potential chemoprevention using statins, metformin or coffee. However, the effectiveness of HCC prevention in clinical practice and at the population level has lagged behind due to patient, provider, system, and societal factors. The Quality in the Continuum of Cancer Care model provides a framework for evaluating the HCC prevention processes, including potential failures that create a gap between efficacy and effectiveness.