An updated Asia Pacific Consensus Recommendations on colorectal cancer screening

Usefulness of mean number of adenomas per positive screenee for identifying meticulous endoscopists among those who achieve acceptable adenoma detection rates

BACKGROUND

Adenoma detection rate (ADR) is a quality indicator for colonoscopy. However, many missed adenomas have subsequently been identified after colonoscopies performed by endoscopists with ADR ≥ 25 %. Adenomas per positive participant (APP; mean number of adenomas detected by an endoscopist among screenees with positive findings) correlates well inversely with adenoma miss rate. This study aimed to evaluate whether APP added additional information on the detection rate for advanced adenomas (AADR) and proximal adenomas (pADR) and among endoscopists with acceptable ADRs (≥ 25 %).

METHODS

A total of 47 endoscopists performed 7339 screening colonoscopies that were retrospectively reviewed. Using a cutoff APP value of 2.0, endoscopist performance was classified as high or low APP. Endoscopist ADRs were also classified as acceptable (25 % - 29 %), high standard (30 % - 39 %) and aspirational (≥ 40 %). Generalized linear models were used to assess the relationship between AADR or pADR, and ADR and APP, after adjusting for potential confounders.

RESULTS

After adjusting for endoscopist performance and patient characteristics, endoscopists with high APP had a significant 2.1 percentage point increase in AADR (95 %CI 0.3 to 3.9; P = 0.02) and a 2.1 percentage point increase in pADR (95 %CI - 0.8 to 5.1; P = 0.15) compared to endoscopists with low APP. In total, 11 (24 %), 18 (38 %), and 18 (38 %) endoscopists were classified as having acceptable, high standard, and aspirational ADRs, respectively. APP values higher than the cutoff were found in 18 %, 44 %, and 72 % of endoscopists with acceptable, high standard, and aspirational ADRs, respectively (P = 0.02).

CONCLUSION

APP is helpful for identifying more meticulous endoscopists who can detect a greater number of advanced adenomas. Endoscopists who achieved an only acceptable ADR had the lowest APP.

MiRNA-202-5p promotes Colorectal Carcinogenesis through suppression of PTEN

Colorectal cancer (CRC) is still one of the leading causes of cancer-associated death in the modern society. The biological function of miR-202-5p for CRC development remains controversial, largely due to the fact that miR-202-5p can be tumor-suppressive or oncogenic in different contexts. Obtained results indicated that aberrant expression of miR-202-5p was observed in majority of human CRC samples and miR-202-5p was transcriptionally up-regulated by c-Myc. In addition, miR-202-5p functions to promote the activation of PI3K/Akt signaling pathway by directly suppressing PTEN. Silencing or enforced expression of miR-202-5p resulted in CRC cell proliferation inhibition and enhancement, respectively. Importantly, decreased PTEN level and increased phosphorylation of Akt were frequently associated with elevated miR-202-5p expression in colorectal cancer tissues. Increased miR-202-5p expression may serve as a tumor promoter by directly targeting PTEN in colorectal cancer.

miR-203a suppresses cell proliferation by targeting RING-finger protein 6 in colorectal cancer

Colorectal cancer (CRC) is one of most common cancers worldwide. Although miR-203a is reported as a tumor suppressor involved in cell progression in some cancers, the role of miR-203a in CRC is still controversial and the underling mechanism of miR-203a in CRC remains unclear. Here, we demonstrated that low expression of miR-203a had poorer survival in CRC patients. miR-203a was down-regulated in most human colon cancer cells. Overexpression of miR-203a could inhibit colon cancer cell proliferation and arrest cell cycle in G1 phase. Bioinformatics and dual luciferase reporter assay confirmed that RING-finger protein 6 (RNF6) was a target gene of miR-203a. Silencing RNF6 inhibited cell proliferation and arrest cell cycle in G1 phase. RNF6 overexpression reversed the effects of miR-203a overexpression in colon cancer cells. Taken together, our data indicate that miR-203a inhibits colon cancer cell proliferation by targeting RNF6, offer novel insights into the regulatory network of miR-203a-modulated cell cycle and proliferation, and suggest that miR-203a a potential therapeutic target in CRC treatment.

Impact of a Telephone Intervention on Bowel Preparation Quality for Colonoscopy in the Elderly

Bowel preparation is the basis of colonoscopy, and adequate bowel preparation is essential to the success of colonoscopy. Studies have been reported that telephone intervention can improve the quality of bowel preparation, while it remains unclear regarding effectiveness with the elderly. The purpose of this study was to evaluate the effect of telephone intervention on the quality of bowel preparation for colonoscopy in elderly outpatients. In total, 162 outpatients older than 65 years were enrolled and randomly divided into a control group and a study group. Patients in the study group were re-educated through telephone by a specific nurse 2 days before colonoscopy, whereas participants in the control group received education only on the day of appointment. The Ottawa score was used to evaluate the quality of bowel preparation between the two groups. In this study, no significant differences were observed in age, gender, body mass index, educational level, smoking and/or alcohol drinking, waiting time to colonoscopy, reasons for colonoscopy, and colonoscopic findings between the control group and the study group. Participants in the study group had higher adequate bowel preparation and compliance than the control group (83.1% vs. 59.5%, p = .03; 96.4% vs. 74.7%, p < .001). Univariate analysis showed that only noncompliance with start time was significantly associated with satisfactory bowel preparation in elderly patients. In conclusion, telephone intervention 2 days before colonoscopy can improve the quality of bowel preparation in the elderly.

The Roadmap of Colorectal Cancer Screening

Colorectal cancer (CRC) is the third most common form of cancer in terms of incidence and the second in terms of mortality worldwide. CRC develops over several years, thus highlighting the importance of early diagnosis. National screening programs based on fecal occult blood tests and subsequent colonoscopy have reduced the incidence and mortality, however improvements are needed since the participation rate remains low and the tests present a high number of false positive results. This review provides an overview of the CRC screening globally and the state of the art in approaches aimed at improving accuracy and participation in CRC screening, also considering the need for gender and age differentiation. New fecal tests and biomarkers such as DNA methylation, mutation or integrity, proteins and microRNAs are explored, including recent investigations into fecal microbiota. Liquid biopsy approaches, involving novel biomarkers and panels, such as circulating mRNA, micro- and long-non-coding RNA, DNA, proteins and extracellular vesicles are discussed. The approaches reported are based on quantitative PCR methods that could be easily applied to routine screening, or arrays and sequencing assays that should be better exploited to describe and identify candidate biomarkers in blood samples.

Factors Associated With Colorectal Cancer Screening Via Immunochemical Fecal Occult Blood Test in an Average-Risk Population From a Multiethnic, Middle-Income Setting

PURPOSE

The Malaysian Ministry of Health had launched free opportunistic screening for colorectal cancer using immunochemical fecal occult blood test (iFOBT) targeting the average-risk individuals since 2014. This study aims to determine factors associated with colorectal cancer screening using iFOBT among the average-risk Malaysian population.

METHODS

A cross-sectional study was conducted at five government-run health clinics in the state of Selangor. Adults with an average risk of colorectal cancer (age > 50 years, asymptomatic, and no family history of colorectal cancer) were recruited using systematic random sampling. An interviewer-administered questionnaire adapted from the Cancer Awareness Measure and Health Belief Model was used.

RESULTS

The median age of participants was 61 years (interquartile range, 56 to 66). Almost 60% of participants indicated their willingness to be screened. However, only 7.5% had undergone iFOBT. Good knowledge of risk factors of colorectal cancer, perceived susceptibility to the disease, and the doctor's recommendation were associated with increased willingness to be screened: adjusted odds ratio (aOR), 1.66 (95% CI, 1.12 to 2.46); aOR, 1.70 (95% CI, 1.08 to 2.70); and aOR, 5.76 (95% CI, 2.13 to 15.57), respectively. Nevertheless, being elderly (aOR, 0.67; 95% CI, 0.45 to 0.99) and high negative perception toward the testing method (iFOBT) (aOR, 0.12; 95% CI, 0.05 to 0.30) were independently associated with lower willingness to be screened. Multivariable analysis within the average-risk individuals who were willing to be screened for colorectal cancer showed that the doctor’s recommendations remained as an important cue for positive action, whereas negative perception toward the test was a significant barrier to the actual uptake of iFOBT.

CONCLUSION

The present findings must be factored in when tailoring colorectal cancer screening promotion activities in multiethnic, middle-income settings.

Performance of common genetic variants in risk prediction for colorectal cancer in Chinese: A two-stage and multicenter study

The efficacy of susceptible variants derived from genome-wide association studies (GWAs) optimizing discriminatory accuracy of colorectal cancer (CRC) in Chinese remains unclear. In the present validation study, we assessed 75 recently identified variants from GWAs. A risk predictive model combining 19 variants using the least absolute shrinkage and selection operator (LASSO) statistics offered certain clinical advantages. This model demonstrated an area under the receiver operating characteristic (AUC) of 0.61 during training analysis and yielded robust AUCs from 0.59 to 0.61 during validation analysis in three independent centers. The individuals carrying the highest quartile of risk score revealed over 2-fold risks of CRC (ranging from 2.12 to 2.90) compared with those who presented the lowest quartile of risk score. This genetic model offered the possibility of partitioning risk within the average risk population, which might serve as a first step toward developing individualized CRC prevention strategies in China.

Classifying interval cancers as false negatives or newly occurring in fecal immunochemical testing

OBJECTIVE

To classify interval colorectal cancers as false negatives or newly occurring cases in a biennial Fecal immunochemical test (FIT) screening program and by various interscreening intervals.

SETTING

Data from the Taiwanese biennial colorectal cancer screening program involving FIT from 2004 to 2014 were used to estimate the incidence rate of asymptomatic colorectal cancer and the rate of its subsequent progression to clinical mode.

METHODS

The sensitivity of detecting asymptomatic colorectal cancers excluding newly developed colorectal cancers was compared to the conventional estimate of sensitivity, the complementary FIT interval cancer rate as a percentage of the expected incidence rate ((1-I/E)%). The relative contribution of newly developed or false-negative cases to FIT interval colorectal cancers was estimated by age and interscreening intervals.

RESULTS

The Taiwanese biennial fecal immunochemical test screening program had a conventional sensitivity estimate of 70.2%. After newly developed colorectal cancers were separated from FIT interval cancers, the ability to detect asymptomatic colorectal cancers increased to 75.5%. FIT interval colorectal cancers from the biennial program mainly resulted from newly developed colorectal cancers (68.8%). The corresponding figures decreased to 61.1% for the annual program but increased to 74.7% for the triennial program. The preponderance of newly developed colorectal cancers among FIT interval cancers was more prominent in screenees aged 50-59  than in those aged 60-69.

CONCLUSIONS

Newly developed colorectal cancers showed a predominance among the FIT interval colorectal cancers in particular in the younger population screened. It is desirable to identify high-risk individuals to offer them a short interscreening interval or advanced detection methods to reduce their odds of developing interval cancer.

Development and Validation of the Asia-Pacific Proximal Colon Neoplasia Risk Score

BACKGROUND & AIMS

Patients found to be at high risk of advanced proximal neoplasia (APN) after flexible sigmoidoscopy screening should be considered for colonoscopy examination. We developed and validated a scoring system to identify persons at risk for APN.

METHODS

We collected data from 7954 asymptomatic subjects (age, 50-75 y) who received screening colonoscopy examinations at 14 sites in Asia. We randomly assigned 5303 subjects to the derivation cohort and the remaining 2651 to the validation cohort. We collected data from the derivation cohort on age, sex, family history of colorectal cancer, smoking, drinking, body mass index, medical conditions, and use of nonsteroidal anti-inflammatory drugs or aspirin. Associations between the colonoscopic findings of APN and each risk factor were examined using the Pearson χ² test, and we assigned each participant a risk score (0-15), with scores of 0 to 3 as average risk and scores of 4 or higher as high risk. The scoring system was tested in the validation cohort. We used the Cochran-Armitage test of trend to compare the prevalence of APN among subjects in each group.

RESULTS

In the validation cohort, 79.5% of patients were classified as average risk and 20.5% were classified as high risk. The prevalence of APN in the average-risk group was 1.9% and in the high-risk group was 9.4% (adjusted relative risk, 5.08; 95% CI, 3.38-7.62; P < .001). The score included age (61-70 y, 3; ≥70 y, 4), smoking habits (current/past, 2), family history of colorectal cancer (present in a first-degree relative, 2), and the presence of neoplasia in the distal colorectum (nonadvanced adenoma 5-9 mm, 2; advanced neoplasia, 7). The c-statistic of the score was 0.74 (95% CI, 0.68-0.79), and for distal findings alone was 0.67 (95% CI, 0.60-0.74). The Hosmer-Lemeshow goodness-of-fit test statistic was greater than 0.05, indicating the reliability of the validation set. The number needed to refer was 11 (95% CI, 10-13), and the number needed to screen was 15 (95% CI, 12-17).

CONCLUSIONS

We developed and validated a scoring system to identify persons at risk for APN. Screening participants who undergo flexible sigmoidoscopy screening with a score of 4 points or higher should undergo colonoscopy evaluation.

Glycosylated Hemoglobin as an Age-Specific Predictor and Risk Marker of Colorectal Adenomas in Non-Diabetic Adults

BACKGROUND

Diabetes is a risk factor for colorectal neoplasms. The association between the level of glycosylated hemoglobin (HbA1c) and the risk of colorectal adenomas (CRAs) in non-diabetic adults needs to be investigated.

METHODS

A cross-sectional study was performed on non-diabetic adults with normal HbA1c level who underwent colonoscopy between January 2010 and December 2016 during health check-ups in our hospital in China. The association between HbA1c level and CRAs was assessed by multiple logistic regression models stratified by age group (<40, ≥40 and <50, and ≥50 years old). The age group-specified thresholds for HbA1c on elevated risk of CRAs were estimated using the piecewise logistic regression.

RESULTS

Among the 2,764 subjects, 445 (16.1%) had CRA. The prevalence of CRA varied across the three age groups. A higher HbA1c level was found to be significantly associated with increased CRA risk in the 40-50 years group (odds ratio [OR]=1.70, 95% confidence interval [CI] 1.04-2.78, p=0.035) after adjusting for other related factors, while this association was borderline significant among the 50 years and older group (OR=1.57, 95% CI 0.97-2.54, p=0.067). Based on the piecewise logistic regression analysis results, the thresholds for HbA1c on elevated risk of CRA were 5.44% for the 40-50 years group and 4.81% for the 50 years and older group, respectively.

CONCLUSIONS

Higher levels of HbA1c, even within the normal range, were associated with elevated CRA risk among non-diabetic adults. The threshold effects of HbA1c on the risk of CRA varied across different age groups, and early screening colonoscopy might be needed for individuals in their 40s and with HbA1c levels ≥5.44%.

The Clinical Significance of Colon Polyp Pathology in Nonalcoholic Fatty Liver Disease (NAFLD) and Its Impact on Screening Colonoscopy in Daily Practice

AIM

Nonalcoholic fatty liver disease (NAFLD) has been known as a risk for the presence of colon polyp and CRC development. This study was aimed to find out the clinical significance of colon polyps' pathology among NAFLD patients.

METHOD

A retrospective database study was done in patients who underwent elective colonoscopy within one-year period in a referral private hospital, Jakarta. Subjects were adult patients who also had documented abdominal ultrasound (US). The association between NAFLD and colonic polyp was analyzed using Chi-square test with odds ratio (OR) and its corresponding 95% confidence interval (CI).

RESULTS

A total of 138 adult patients were enrolled; 68 (51.1%) were men. Patients' mean age was 56.8 ± 15.3 years old. Colon polyps were found in 49 (35.5%) cases; the most common histopathology was adenoma (42.9%). NAFLD was found in 68 (49.3%) of patients. Colon polyps were found to be more among patients with NAFLD than in those without NAFLD (44.1% vs. 27.1%; OR: 2.119; 95% CI: 1.040-4.318). Colon polyps were found in 30 (44.1%) NAFLD patients, where 18 (26.5%) patients had adenomatous polyp, and from this subset of patients with adenomatous polyp, 6 (8.8%) patients had mild dysplasia, 8 (11.8%) had moderate dysplasia, 1 (1.5%) had severe dysplasia, and 3 (4.4%) had adenocarcinoma.

CONCLUSIONS

NAFLD is associated with increased risk of any colon polyp, regardless of the histopathological type, compared with patients without NAFLD. This finding implies the necessity to perform screening colonoscopy in patients with NAFLD in the future.

Development and validation of prognostic nomograms for early-onset locally advanced colon cancer

BACKGROUND

The incidence of colorectal cancer in patients younger than 50 years has been increasing in recent years.

OBJECTIVE

Develop and validate prognostic nomograms predicting overall survival (OS) and cancer-specific survival (CSS) for early-onset locally advanced colon cancer (EOLACC) based on the Surveillance, Epidemiology, and End Results (SEER) database.

RESULTS

The entire cohort comprised 13,755 patients with EOLACC. The nomogram predicting OS for EOLACC displayed that T stage contributed the most to prognosis, followed by N stage, regional nodes examined (RNE) and surgery. The nomogram predicting CSS for EOLACC demonstrated similar results. Various methods identified the discriminating superiority of the nomograms. X-tile software was used to classify patients into high-risk, medium-risk, and low-risk according to the risk score of the nomograms. The risk stratification effectively avoided the survival paradox.

CONCLUSIONS

We established and validated nomograms for predicting OS and CSS based on a national cohort of almost 13,000 EOLACC patients. The nomograms could effectively solve the issue of survival paradox of the AJCC staging system and be an excellent tool to integrate the clinical characteristics to guide the therapeutic choice for EOLACC patients.

METHODS

Nomograms were constructed based on the SEER database and the Cox regression model.

Mobile messenger-initiated reminders improve longitudinal adherence in a community-based, opportunistic colorectal cancer screening program: A single-blind, crossover randomized controlled study

BACKGROUND

The fecal immunochemical test (FIT) is a cost-effective colorectal cancer (CRC) screening tool. However, longitudinal adherence, a factor that is critical to the success to any FIT-based screening program, often is poor. The authors hypothesized that reminders sent via mobile messengers, such as WhatsApp, improve such adherence.

METHODS

In the current single-blind, randomized study, subjects from an opportunistic FIT screening program who had a negative FIT result the year prior were randomly allocated (1:1) to receive either a 1-off reminder via the WhatsApp messenger (WR) 1 month prior to the due appointments or no reminder (NR). All subjects were blinded to study participation and group allocation. At 24 months after randomization, a crossover of intervention was performed among those individuals who remained in the FIT program. The primary outcome was FIT adherence, defined as the pick-up and on-time return of the FIT. The secondary outcome was FIT adherence after the crossover.

RESULTS

A total of 500 subjects were randomized to receive WR (250 subjects) or NR (250 subjects). Three individuals were excluded from analysis (1 died and 2 underwent colonoscopy). Both the FIT pick-up rate (80.3% vs 59.3%; P < .001) and return rate (79.9% vs 57.3%; P < .001) were significantly higher in the WR group compared with the NR group. After crossover of intervention (452 subjects), the WR group again was found to have a higher FIT pick-up rate (79.1% vs 52.9%; P < .001) and return rate (78.2% vs 52.4%; P < .001).

CONCLUSIONS

Text reminders sent via mobile messenger appear to improve the longitudinal adherence to FIT-based opportunistic CRC screening programs. The routine use of this technology in CRC screening should be considered.

Factors associated with participation in colorectal cancer screening: A population-based study of 7200 individuals

OBJECTIVE

This study aimed to evaluate how the knowledge and perception towards colorectal cancer (CRC) screening had been changed in a large population, and identified factors associated with its participation based on factors pertinent to the Health Belief Model (HBM).

METHODS

Data from 3600 screening participants and 3600 non-participants were collected through a telephone survey via simple random sampling of telephone numbers in a territory-wide directory from December 2016 to November 2018. Sociodemographic factors; the enabling factors of screening as well as the barriers of screening were collected. The changes in these factors were evaluated by Pearson's chi-square trend test. A logistic regression model was constructed to identify the association between the above factors and CRC screening participation.

RESULTS

The knowledge level (67.9% to 85.4%, p < 0.001), perceived severity of having CRC (37.7%-42.8%, p < 0.01), perceived benefits of screening (54.9%-72.1%, p < 0.001), and reductions in barriers (14.1%-5.1%, p < 0.001) of CRC screening significantly improved among the non-users. Subjects with older age (adjusted odds ratio (AOR): 2.01, p < 0.001), higher knowledge level of screening methods (AOR: 6.68, p < 0.001), greater perceived severity (AOR: 2.04, p < 0.001) and coverage of insurance (AOR: 1.22, p < 0.01) were more likely to participate. In contrast, more affluent subjects (AOR: 0.69, p < 0.001), female individuals (AOR: 0.63, p < 0.001), higher level of perceived psychological (AOR: 0.54, p < 0.001) and access barriers (AOR: 0.55, p < 0.001) were associated with poorer participation.

CONCLUSION

These findings demonstrated a substantial increase in the enabling factors of CRC screening, including knowledge, perceived severity and perceived benefits. The study also identified the target groups such as younger individuals, females and more affluent people among whom more intensive educational initiatives are needed to enhance their participation.

Association between high fatty liver index and development of colorectal cancer: a nationwide cohort study with 21,592,374 Korean

BACKGROUND/AIMS

In Korea, the incidence of colorectal cancer (CRC) and nonalcoholic fatty liver disease (NAFLD) has increased due to a westernized lifestyle. This study investigated whether a high fatty liver index that reflects NAFLD correlates with CRC.

METHODS

Data from the National Health Insurance Corporation 2009 to 2012 were analyzed. NAFLD disease was defined as a fatty liver index > 60 in the absence of alcohol consumption of ≥ 30 g/day.

RESULTS

NAFLD was identified in 2,543,649 (11.8%) of 21,592,374 participants. CRC was identified in 19,785 (0.8%) of participants with NAFLD (fatty liver index ≥ 60) and in 80,871 (0.6%) participants without NAFLD (fatty liver index < 30). Multivariate logistic regression analysis demonstrated an independent association between NAFLD and CRC after adjusting for other confounders (hazard ratio, 1.13; odds ratio, 1.12 to 1.15). In subgroup analyses, fatty liver index ≥ 60 was associated with CRC regardless of body mass index, but the association was more prominent in persons with a normal index. NAFLD, in the absence of diabetes, hypertension, or dyslipidemia, was more highly associated with CRC than when one or more of these conditions are present.

CONCLUSION

CRC should be considered as a possibility in patients with fatty liver index ≥ 60, even in the absence of obesity or other metabolic syndromes.

The effect of miRNA and autophagy on colorectal cancer

Colorectal cancer (CRC) has become a concern because of its high recurrence rate and metastasis rate, low early diagnosis rate and poor therapeutic effect. At present, various studies have shown that autophagy is closely connected with the occurrence and progression of CRC. Autophagy is a highly cytosolic catabolic process involved in lysosomes in biological evolution. Cells degrade proteins and damaged organelles by autophagy to achieve material circulation and maintain cell homeostasis. Moreover, microRNAs are key regulators of autophagy, and their mediated regulation of transcriptional and post-transcriptional levels plays an important role in autophagy in CRC cells. This review focuses on the recent research advances of how autophagy and related microRNAs are involved in affecting occurrence and progression of CRC and provides a new perspective for the study of CRC treatment strategies.

The Impact of a Comprehensive Risk Prediction Model for Colorectal Cancer on a Population Screening Program

BACKGROUND

In many countries, population colorectal cancer (CRC) screening is based on age and family history, though more precise risk prediction could better target screening. We examined the impact of a CRC risk prediction model (incorporating age, sex, lifestyle, genomic, and family history factors) to target screening under several feasible screening scenarios.

METHODS

We estimated the model's predicted CRC risk distribution in the Australian population. Predicted CRC risks were categorized into screening recommendations under 3 proposed scenarios to compare with current recommendations: 1) highly tailored, 2) 3 risk categories, and 3) 4 sex-specific risk categories. Under each scenario, for 35- to 74-year-olds, we calculated the number of CRC screens by immunochemical fecal occult blood testing (iFOBT) and colonoscopy and the proportion of predicted CRCs over 10 years in each screening group.

RESULTS

Currently, 1.1% of 35- to 74-year-olds are recommended screening colonoscopy and 56.2% iFOBT, and 5.7% and 83.2% of CRCs over 10 years were predicted to occur in these groups, respectively. For the scenarios, 1) colonoscopy was recommended to 8.1% and iFOBT to 37.5%, with 36.1% and 50.1% of CRCs in each group; 2) colonoscopy was recommended to 2.4% and iFOBT to 56.0%, with 13.2% and 76.9% of cancers in each group; and 3) colonoscopy was recommended to 5.0% and iFOBT to 54.2%, with 24.5% and 66.5% of cancers in each group.

CONCLUSIONS

A highly tailored CRC screening scenario results in many fewer screens but more cancers in those unscreened. Category-based scenarios may provide a good balance between number of screens and cancers detected and are simpler to implement.

Human oral microbiome dysbiosis as a novel non-invasive biomarker in detection of colorectal cancer

Background: The oral microbiome may play an important role in colorectal carcinogenesis. However, few studies have investigated the association between oral microbiome and the development of colorectal cancer (CRC). We aimed to investigate whether oral health-colorectal tumor association has an underlying microbial basis, in the quest for novel non-invasive biomarkers for CRC.

Methods: We collected oral swab samples from 161 patients with CRC, 34 patients with colorectal adenoma (CRA), and 58 healthy volunteers. The oral microbiota was assessed using 16S rRNA sequencing. We characterized oral microbiome, identified microbial markers, constructed and validated colorectal tumor (CRA and CRC) classifier.

Results: Oral microbial composition and diversity were significantly different among the three groups, and the CRA group had the highest diversity. Analysis of the functional potential of oral microbiota demonstrated that the pathway involving cell motility was overrepresented in the CRA and CRC groups relative to that in the healthy controls. Moreover, a random forest model was constructed based on oral microbial markers, which could distinguish the colorectal tumor groups from the healthy controls and achieve a powerful classification potential in the discovery and validation cohorts.

Conclusion: This study suggests a potential association between oral microbiome dysbiosis and colorectal cancer. Oral microbiota-based biomarkers may be helpful in predicting the risks for the development of CRA and CRC.

Strategies to Improve Persistent Adherence in Colorectal Cancer Screening

Colorectal cancer is a major cause of morbidity and mortality, and screening has been shown to reduce morbidity and mortality. This review highlights pertinent aspects of adherence to screening including the various options available and key concepts to consider in any systematic program. Persistent adherence, which is key to an efficacious screening program, is the compliance with repeated screening tests over a period of time. A "chain of survival" mindset emphasizes the stepwise, sequential and persistent approach to screening and is a helpful concept to drive the message of persistent adherence. A framework for the patient and physician interactions that support screening intervention is examined, and various factors that impact both patient and physician adoption and screening modality recommendations are reviewed. While systems-based approaches to screening have great utility in automation and monitoring in a surveillance program, some emerging data suggests that the human touch is still an essential driver for active participation in these programs. Finally, the proportion of time concept is discussed as a useful index for monitoring persistent adherence in both individuals and populations.

Cost-effectiveness analysis of colorectal cancer screening using colonoscopy, fecal immunochemical test, and risk score

BACKGROUND AND AIM

A risk-stratification score may be useful for colorectal cancer (CRC) screening, alongside screening colonoscopy (CS) and fecal immunochemical test (FIT). This study aimed to evaluate the effectiveness and cost-effectiveness of population-based CRC screening strategies using CS, FIT, and the Japanese CRC screening score.

METHODS

The effectiveness in quality-adjusted life years (QALYs), cost-effectiveness, and required number of CS procedures were evaluated for screening strategies with primary screening CS (strategy 1), FIT (strategy 2), and the risk score (strategy 3), using a simulation model analysis with two scenarios. In scenario 1, uptake rates for all tests were 60%. In scenario 2, uptake rates for FIT and a risk score were 40%, and those for screening CS and CS following a positive FIT or high risk score were 20% and 70%, respectively.

RESULTS

In scenario 1, strategy 1 gained the highest QALYs and required the highest cost. The incremental cost-effectiveness ratios per QALY gained for strategy 1 against the others were lower than 5 000 000 JPY. Strategy 1 required more than twice as many CS procedures as the other strategies. In scenario 2, strategy 3 had the highest QALYs and lowest cost, and strategy 1 had the lowest QALYs and highest cost.

CONCLUSIONS

Screening CS has the potential to be the most effective and cost-effective form of CRC screening, although it requires a large number of CS procedures. However, if non-invasive tests are preferred by recipients, other screening strategies, particularly those using the risk score, can be more effective and cost-effective.

PP9, a steroidal saponin, induces G2/M arrest and apoptosis in human colorectal cancer cells by inhibiting the PI3K/Akt/GSK3β pathway

Colorectal cancer (CRC) represents one of the commonest malignancies around the world. PP9, a natural steroidal saponin, was firstly isolated from the rhizomes of Paris polyphylla var. latifolia. However, the therapeutic effects of PP9 on CRC and the underlying molecular mechanism remain undefined. Here, we demonstrated that treatment with PP9 time- and dose-dependently inhibited HT-29 and HCT116 cells without significantly inhibiting normal NCM460 cells. Furthermore, our results indicated that PP9 effectively induced G2/M phase arrest by upregulating p21 and suppressing cdc25C, Cyclin B1 and cdc2. Meanwhile, PP9 upregulated cleaved Caspase 3, cleaved Caspase 9 and cleaved PARP and Bax, while downregulating Bcl-2 to stimulate cell apoptosis. Mechanistically, PP9-suppressed PI3K/Akt/GSK3β signaling, while the PI3K inhibitor LY294002 augmented PP9-mediated apoptosis, G2/M arrest and effects on PI3K/Akt/GSK3β related proteins. Finally, we showed that PP9 (10 mg/kg) significantly reduced tumor growth in nude mouse CRC xenografts, more potently than 5-Fu (20 mg/kg). Jointly, these data firstly demonstrated that PP9 promotes G2/M arrest and apoptotic death in CRC cells through PI3K/Akt/GSK3β signaling suppression, suggesting that PP9 could be considered a new and promising candidate for CRC therapy.

Risk factors including night shift work of colorectal polyp

Background

The destruction of circadian rhythms by night shift work affects major circadian genes, which are known to play a role in advancing or killing the cell cycle through tumor suppressor genes. To find out whether night shift work affects the incidence of colorectal cancer, which was found to be associated with long-term night shift work in previous studies, we surveyed effect of night shift work on colorectal polyps that have a higher incidence than colorectal cancer and can progress to colorectal cancer.

Methods

To examine the correlation between rotating night shifts and colorectal polyps, a survey was conducted with 299 men aged 40–60 years from two university hospitals. We examined lifestyle, work history, work patterns, and colonoscopy results. The differences in prevalence among the groups was compared, and prevalence ratio (PR) was calculated via generalized linear modeling.

Results

The prevalence of colorectal polyps in night shift and non-shift workers were 53.0% and 33.5%, respectively. After adjusting for age, smoking status, dietary habits, family history of colorectal cancer, obesity, job type, night shift work (PR: 1.13, 95% CI: 1.02–1.25) was a risk factor of colorectal polyps.

Conclusions

The risk of colorectal polyps was greater in night shift workers than non-shift workers. Also risk of colorectal polyp was higher in older group. Our study investigated colorectal polyp instead of colorectal cancer and lacks information about types and gene mutations of colorectal polyps. Further study is needed to clarify effect of night shift work on development of colorectal cancer.

Liquid Biopsy of Extracellular Vesicle-Derived miR-193a-5p in Colorectal Cancer and Discovery of Its Tumor-Suppressor Functions

Previously, abnormal extracellular vesicle (EV) sorting of miR-193a was identified in colorectal cancer (CRC) progression. Although a reduced level of miR-193a-5p in plasma/serum has been reported in many different types of cancer, the EV-derived miR-193a-5p level in CRC and its potential application as a minimally invasive biomarker are still unknown. Here, we evaluated the circulating EV-derived miR-193a-5p expression levels in a cohort of 101 participants by real-time quantitative polymerase chain reaction (RT-qPCR). We found that plasma EV-miR-193a-5p decreased significantly in CRC patients as compared with precancerous colorectal adenoma (CA) and non-cancerous control (NC) individuals. The circulating EV-miR-193a-5p showed an area under the receiver operating characteristic curve (AUC) of 0.740 in distinguishing CRC from CA and an AUC of 0.759 in distinguishing CRC from NC. Furthermore, the suppression on CRC cells of miR-193a-5p was verified by transwell, MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium), EdU, RT-qPCR, and western blotting. Bioinformatic analysis predicted 32 genes, which were the most likely miR-193a-5p targeted and mainly focused on tumor progression. Among them, we revealed that miR-193a-5p could inhibit CRC migration and invasion via targeting tumor-associated genes like CUT-like homeobox 1 (CUX1) and intersectin 1 (ITSN1). In conclusion, miR-193a-5p could suppress CRC development, and decreased plasma EV-miR-193a-5p could be a promising biomarker for human CRC detection.

Colonoscopic screening is associated with reduced Colorectal Cancer incidence and mortality: a systematic review and meta-analysis

It is the great priority to detect colorectal cancer (CRC) as early as possible, finally to reduce the incidence and mortality of CRC. However, although colonoscopy is recommended in many consensuses, yet no one systematic review is conducted to figure out how colonoscopy could change the incidence and mortality. In our study, we conducted a comprehensive meta-analysis to evaluate the association between colonoscopy screening and the incidence or mortality of CRC. PubMed, EMBASE, and PMC database were systematically searched from their inception to June 2020. A total of 13 cohort and 16 case-control studies comprising 4,713,778 individuals were obtained in this review. Our results showed that colonoscopy was associated with a 52% RR reduction in incidence of CRC (RR: 0.48, 95% CI: 0.46-0.49) and 62% RR reduction in mortality of CRC (RR: 0.38, 95% CI: 0.36-0.40). Subgroup analysis of different interventions, study design, country, sample size, age or sex showed that the incidence and mortality reduction remained consistent, and colonoscopy screening had the same effect on people below and above 50. Our study indicated that colonoscopy could significantly reduce the incidence and mortality of CRC.

A young woman who developed ascending colon cancer 2 years after the onset of ulcerative colitis

Guidelines recommend surveillance colonoscopy for patients with an ulcerative colitis (UC) duration of 8-10 years. We experienced a patient who had not undergone UC surveillance. A 35-year-old Japanese woman developed diarrhea and abdominal pain in January 2018 and was diagnosed with UC. She underwent medical therapy, and 18 months after onset of UC colonoscopy indicated that her UC activity was remission and showed no cancer lesions. Twenty-four months after onset, colonoscopy revealed a tumor in the ascending colon, and the biopsy revealed tubular adenocarcinoma. She had no family history of colorectal cancer. There were no findings of distant metastases or primary sclerosing cholangitis. Laparoscopy-assisted anus-preserving total proctocolectomy, the creation of a J-type ileal pouch, ileal pouch anal anastomosis, and the creation of an ileostomy were performed. The pathological report was type 3, 30 × 27-mm, adenocarcinoma (por2 > tub2), pT4a, Ly1a, V1a, budding grade 3, pN0, M0, Stage IIb. Some colitic cancers such as our patient's may not conform to the existing guidelines. When a colonoscopy is being performed for a UC patient, even if its timing is less < 8 years since the UC onset, suspicious lesions should be biopsied considering the possibility of cancer.

Does theory of planned behaviour play a role in predicting uptake of colorectal cancer screening? A cross-sectional study in Hong Kong

OBJECTIVE

Colorectal cancer (CRC) ranked second in terms of cancer mortality worldwide. It is associated with a substantial global disease burden. We aimed to examine whether the theory of planned behaviour (TPB) could predict the uptake of faecal immunochemical test to inform novel strategies for enhancing CRC screening participation in population-based programmes.

DESIGN

Cross-sectional study.

SETTINGS

A Hong Kong-based and territory-wide telephone survey was conducted during the study period from October 2017 to November 2018.

PARTICIPANTS

4800 asymptomatic individuals aged 61-70 years who can communicate in Cantonese were recruited during the survey period. Those who had a history of CRC, chronic bowel inflammation, two or more first-degree relatives with CRC, and received colonoscopy in the past 10 years or faecal occult blood test in the past 5 years were excluded.

OUTCOME MEASURES

The association between CRC screening uptake and the factors pertinent to TPB was analysed by univariable and multivariable regression models and the mediating effect of intention. We adjusted for age, gender, educational level, marital and working status, as well as household income.

RESULTS

Multivariable regression analysis showed that high perceived behavioural control (adjusted OR (AOR)=12.35, 95% CI 8.21 to 18.60, p<0.001), high intention for CRC screening (AOR=7.86, 95% CI 6.60 to 9.36, p<0.001) and positive attitude towards CRC screening (accuracy and effectiveness: AOR=1.19, 95% CI 1.03 to 1.38, p<0.05; embarrassment and apprehension: AOR=4.27, 95% CI 3.13 to 5.82, p<0.001) were significantly associated with CRC screening uptake. Mediation analysis found that the effect of social norms on screening behaviour was primarily mediated by intention (83.2%), and this indirect, mediated effect accounted for 21.7% to 24.1% of total effects of other constructs in TPB on screening behaviour.

CONCLUSIONS

The variables pertinent to TPB could successfully predict CRC screening uptake. Promotion of CRC screening based on interventions that increase perceived behavioural control and behavioural intention could potentially enhance screening uptake. Further studies are needed to establish the cause and effect relationship among these variables and screening uptake, as well as to evaluate the cost-effectiveness of such interventions.

Factors Associated with Participation in Stool Based Colorectal Screening in Brunei Darussalam

INTRODUCTION

Colorectal cancers (CRC) continues to increase worldwide and is associated with significant morbidity and mortality. CRC can be prevented through early detection using several modalities. However, like any screening program participation remains suboptimal. This study assessed the factors associated with participation in a stool based CRC screening that was carried out as part of an Integrated Health Screening Survey for civil servants.

MATERIALS AND METHODS

Civil servants who participated in a health survey (N=10,756, mean age 48.08 ± 5.26 years old) were studied. Demographic factors (gender, age groups, marital status, employment status, body mass index [BMI] categories, smoking status, personal and family history of cancers) were analyzed to assess for features associated with willingness to participate in this fecal immunohistochemistry test (FIT) screening for CRC. Comorbid conditions studied were cardiac disease, diabetes mellitus, dyslipidemia, hypertension and stroke. Multivariate analysis was performed to evaluate variables associated with participation in CRC screening programme.

RESULTS

Of the invited 10,756 participants, 7,360 returned a stool specimen giving a participation rate of 68.4%. Those who participated were significantly older (60 years [77.8%], p0.05). Multivariate analyses showed that older age (45-49, 50-54, 55-59 and >60) and employment status (professional) remained significant factors associated with participation in a stool based CRC screening.

CONCLUSIONS

Our study showed that older age and professional employment status were significantly associated with willingness to participate in a stool based CRC screening.

A Genomic Test for Colorectal Cancer Risk: Is This Acceptable and Feasible in Primary Care?

INTRODUCTION

Genomic tests can predict risk and tailor screening recommendations for colorectal cancer (CRC). Primary care could be suitable for their widespread implementation.

OBJECTIVE

We aimed to assess the feasibility and acceptability of administering a CRC genomic test in primary care.

METHODS

Participants aged 45-74 years recruited from 4 Australian general practices were offered a genomic CRC risk test. Participants received brief verbal information about the test comprising 45 CRC-associated single-nucleotide polymorphisms, before choosing whether to undertake the test. Personalized risks were given to testers. Uptake and knowledge of the genomic test, cancer-specific anxiety (Cancer Worry Scale), psychosocial impact (Multidimensional Impact of Cancer Risk Assessment [MICRA] score), and impact on CRC screening behaviour within 6 months were measured.

RESULTS

In 150 participants, test uptake was high (126, 84%), with 125 (83%) having good knowledge of the genomic test. Moderate risk participants were impacted more by the test (MICRA mean: 15.9) than average risk participants (mean: 9.5, difference in means: 6.4, 95% confidence interval (CI): 1.5, 11.2, p = 0.01), but all scores were low. Average risk participants' cancer-specific anxiety decreased (mean differences from baseline: 1 month -0.5, 95% CI: -1.0, -0.1, p = 0.03; 6 months -0.6, 95% CI: -1.0, -0.2, p = 0.01). We found limited evidence for genomic testers being more likely to complete the risk-appropriate CRC screening than non-testers (41 vs. 17%, odds ratio = 3.4, 95% CI: 0.6, 34.8, p = 0.19), but some mediators of screening behaviour were altered in genomic testers.

CONCLUSIONS

Genomic testing for CRC risk in primary care is acceptable and likely feasible. Further development of the risk assessment intervention could strengthen the impact on screening behaviour.

Second-generation colon capsule endoscopy for detection of colorectal polyps: A meta-analysis

Background: Colorectal cancer counts as the third prevalent type of cancer and the fourth cause of death worldwide. The second-generation colon capsule endoscopy (CCE-2) is a new technology for the diagnosis of colon cancer. The aim of this review was to provide information on the diagnostic accuracy (diagnostic effectiveness) of the second-generation colon capsule endoscopy compared to colonoscopy for the diagnosis of colon cancer and disorders.

Methods: A systematic review of literature in PubMed, Scopus, Science Direct, and Cochrane Library and Iranian databases, such as MagIran, SID, Irandoc, the grey literature (via Google Scholar) was conducted on February 30, 2018. QUADAS-2 was used to assess the quality of the studies. MetaDiSc 2.0 software was used for the meta-analysis.

Results: In this review, 480 records were identified. Eight prospective cohort articles were included among which 7 included in the meta-analysis. For the diagnosis of colorectal polyps with a diameter of 6-10 mm, the pooled sensitivity and specificity were 84% (95% CI, 80% -88%) and 88% (95%CI, 85% -90%). For the diagnosis of 10 mm or bigger colorectal polyps, the pooled sensitivity and specificity were 84% (95% CI, 76%-89%) and 96% (95% CI, 94 %-97%). The sensitivity and specificity of the capsule in the detection of any size polyps were 93% (95% CI, 97%-84%) and 66% (95% CI, 48%-81%), respectively.

Conclusion: There is little evidence to show the accuracy of CCE-2. Nevertheless, this review showed that the second-generation colon capsule endoscopy has good accuracy in the detection of polyps and colorectal cancer among high- and middle-risk patients.

Positive Fecal Immunochemical Test Results Are Associated with Increased Risks of Esophageal, Stomach, and Small Intestine Cancers

Background: The current guideline does not recommend upper gastrointestinal evaluation for patients with a positive fecal immunochemical test (FIT) and negative colonoscopy results. However, this indication was based on low-quality evidence as data on this issue are very limited. We assessed the risk of proximal cancers (oral or throat, esophageal, stomach, and small intestine cancers) after negative or positive FIT results in the Korean National Cancer Screening Program (NCSP). Methods: Using the NCSP databases, we collected data on participants who underwent FIT between 2009 and 2011. Participants were classified based on FIT results and colorectal cancer (CRC) diagnosed within 1 year after FIT as FIT− (n = 5,551,755), FIT+/CRC− (n = 368,553), and FIT+/CRC+ (n = 12,236). Results: The incidence rates of overall proximal cancers in FIT−, FIT+/CRC−, and FIT+/CRC+ patients within 1, 2, and 3 years after FIT were 0.38%, 0.68%, and 2.26%; 0.57%, 0.93%, and 2.74%; and 0.79%, 1.21%, and 3.15%, respectively. After adjusting confounding variables, the risks of esophageal, stomach, and small intestine cancers as well as overall proximal cancers within 1, 2, and 3 years after FIT were higher in FIT+/CRC− patients than those in FIT− patients. However, the risk of oral or throat cancer did not differ between FIT− and FIT+/CRC− patients. The risks for oral or throat cancer and small intestine cancer were higher in FIT+/CRC+ patients than those in FIT+/CRC− patients. Conclusions: In this population-based study, FIT+/CRC− patients were at higher risk for esophageal, stomach, and small intestine cancers than were FIT− patients, suggesting that positive FIT results were associated with these cancers.

Calculating the Starting Age for Screening in Relatives of Patients With Colorectal Cancer Based on Data From Large Nationwide Data Sets

BACKGROUND & AIMS

Although colorectal cancer (CRC) screening guidelines acknowledge the need for earlier screening for high-risk individuals, such as those with family history of CRC, there is limited information on how many years earlier these high-risk individuals should be screened; current practice is based on weak evidence. We aimed to provide risk-adapted recommendations on the starting age of CRC screening for individuals with different family histories.

METHODS

We collected data from nationwide family-cancer data sets in Sweden and calculated risk-adapted starting ages of screening for individuals with different family histories of CRC. Family history was defined as a dynamic (time-dependent) variable, allowing for changes during the follow-up period of 1958 through 2015.

RESULTS

During a follow-up of 12,829,251 individuals with genealogy information, 173,796 developed CRC. The 10-year cumulative risk for the average-risk population at age 50 years (the guideline-recommended age for screening) was 0.44%. Individuals with different family histories of CRC attained this equivalent 0.44% risk 3-29 years earlier than their peers in the general population without such a family history. For example, individuals with 1 affected first-degree relative diagnosed before age 45 years reached the corresponding risk level 16 years earlier.

CONCLUSIONS

We determined risk-adapted starting ages of CRC screening for close or distant relatives of patients with CRC, using high quality nationwide data sets. These findings might be used in counselling individuals about the appropriate age to start CRC screening, to optimize screening practice, and to supplement guidelines for CRC screening.

Family history of colorectal cancer and prevalence of advanced colorectal neoplasia in asymptomatic screened populations in different age groups

BACKGROUND AND AIMS

The clinical significance of a family history (FH) of colorectal cancer (CRC) in first-degree relatives (FDRs) in CRC screening stratified by different age groups of screened individuals is not fully understood. We investigated the relationship between FH and the presence of advanced colorectal neoplasia (ACN) in screened individuals in different age groups.

METHODS

Data from screened individuals aged 40 to 54 years (n = 2263) and 55 to 69 years (n = 2621) who underwent their first-ever screening colonoscopy were analyzed. The relationship between FH and ACN was examined, and a multivariate logistic regression analysis incorporating other baseline characteristics was performed.

RESULTS

Among individuals aged 40 to 54 years, the prevalence of ACN was significantly higher in 249 individuals with affected FDRs than in those without (5.6% vs 1.6%; P < .01), with an adjusted odds ratio of 3.7 (95% confidence interval, 1.9-7.0; P < .01); the prevalence was particularly high in those having FDRs with CRC mortality (7.3%). Among individuals aged 55 to 69 years, the prevalence of ACN was not significantly different between 291 individuals with affected FDRs and those without (5.8% vs 5.8%; P = .95); however, individuals with 2 FDRs with CRC and mortality showed a high prevalence of ACN (17.4% and 42.9%, respectively).

CONCLUSIONS

An FH of CRC in FDRs was associated with a higher prevalence of ACN in younger individuals, with a particularly high impact of FH of CRC mortality. In contrast, the impact of FH was weaker in older individuals except those having 2 FDRs with CRC or mortality.

Perceived Deterrence Towards Colonoscopy for Colorectal Cancer Screening among Northern Malaysia Population: A Qualitative Study

BACKGROUND

Patients with positive immunochemical faecal occult blood test results were found to have poor compliance for a subsequent colonoscopy procedure. This study was conducted to explore patients' perceived deterrence for colonoscopy following a positive stool test.

METHODS

Using qualitative study method, a phone interview was conducted with 16 patients to elicit their views on the reasons for failure to attend the colonoscopy procedure following a positive stool test. The interviews were audio recorded, transcribed verbatim and translated before proceeded with the data analysis. Content analysis was made on the translated interview, followed by systematic classification of data by major themes.

RESULTS

Reasons for nonattendance were categorized under five main themes; unnecessary test, fear of the procedure, logistic obstacles (subthemes; time constraint, transportation problem), social influences, and having other health priority. Lacking in information about the procedure during the referral process was identified to cause misperception and unnecessary worry towards colonoscopy. Fear of the procedure was commonly cited by female respondents while logistic issues pertaining to time constraint were raised by working respondents.

CONCLUSIONS

More effective communication between patients and health care providers are warranted to avoid misconception regarding colonoscopy procedure. Support from primary care doctors, customer-friendly appointment system, use of educational aids and better involvement from family members were among the strategies to increase colonoscopy compliance.

Diagnostic Value of Combining miRNAs, CEA Measurement and the FOBT in Colorectal Cancer Screening

Introduction

Colorectal cancer (CRC) is one of the most common illnesses that seriously threatens human health; many papers have reported that microRNAs (miRNAs) are promising biomarkers for cancer detection. However, miRNAs have not been used in clinical practice even though they are superior to the currently used screening tools, such as the fecal occult blood test (FOBT) and carcinoembryonic antigen (CEA) measurement.

Methods

In this study, we focused on the usefulness of a panel of miRNAs and the combination of miRNAs with the FOBT and CEA measurement, the currently used general diagnosis methods, to improve the accuracy of CRC diagnosis.

Results

The results showed that the miRNA panel has great potential value as a diagnostic biomarker with high specificity and sensitivity, and further analysis demonstrated that the miRNA panel had higher sensitivity and specificity than the FOBT and CEA measurement, even when these methods were combined. More importantly, although the miRNA panel is superior to the FOBT and CEA measurement, it cannot replace them.

Conclusions

In this research, we investigated whether complementarity exists between the miRNA panel and the FOBT and CEA measurement for CRC diagnosis. Interestingly, the results indicated that the FOBT and CEA measurement could improve the positivity rate of the miRNA panel as a biomarker and vice versa.

Serum level of long noncoding RNA B3GALT5-AS1 as a diagnostic biomarker of colorectal cancer

Aim: Long noncoding RNA (lncRNA) B3GALT5-AS1 has been reported as a biomarker for cancer monitoring. This research aims to identify serum long noncoding RNA B3GALT5-AS1 as a new biomarker for the diagnosis of colorectal cancer (CRC) and evaluate its clinical value. Materials & methods: Serum B3GALT5-AS1 expression levels were measured by quantitative real-time PCR. Results: The level of B3GALT5-AS1 in CRC patients was significantly lower than that of healthy patients (p < 0.0001). Further exploration validated that high serum B3GALT5-AS1 level was related to tumor node metastasis (TNM) stage (p = 0.008) and histological differentiation (p = 0.027). Compared with the healthy control group, AUC^ROC of serum B3GALT5-AS1 in the CRC group was 0.762 with 95% CI: 0.698-0.826 (p < 0.0001). Conclusion: B3GALT5-AS1 may be served as a diagnostic marker for distinguishing CRC patients from healthy people.

Global Prevalence of Colorectal Neoplasia: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Most colorectal cancers (CRC) arise from colorectal adenomas, yet there is not enough information on global prevalence to inform health care policy. We examined the prevalence of any type of adenomas, advanced adenomas (AADs), and CRC according to age, sex, ethnicity, geographic regions, and anatomic location (proximal vs distal).

METHODS

MEDLINE and Embase were searched from their inception through May 1, 2018, to identify population-based, observational studies that reported the prevalence of colorectal neoplasia. Studies on participants 15 years or older, with a sample size of 500 persons or more, were included. Metaprop (College Station, TX) was used to model within-study variability by binomial distribution and Freeman-Tukey Double Arcsine Transformation to stabilize the variances. The prevalence figures were presented by proportions and their 95% CIs using random-effects models.

RESULTS

Our meta-analysis included 70 studies involving 637,414 individuals. The overall prevalence rates of adenoma (23.9%; 95% CI, 22.2%-25.8%), AAD (4.6%; 95% CI, 3.8%-5.5%), and CRC (0.4%, 95% CI, 0.3%-0.5%) were calculated. Subgroup analysis indicated that prevalence values (adenomas, AADs, and CRCs) were higher among men (29.7%, 6.5%, and 0.8%, respectively) than women (19.3%, 3.8% and 0.4%, respectively), among older adults (25.9%, 5.2%, and 0.6%, respectively) than younger adults (14.6%, 1.6%, and 0.1%, respectively), among Caucasians (23.7%, 6.6%, and 0.5%, respectively) than other ethnicities, in European countries (25.9%, 8.4%, and 0.8%, respectively) than other countries, and among patients with proximal (25.9%, 5.3%, and 0.1%, respectively) vs distal neoplasia.

CONCLUSIONS

In a systematic review and meta-analysis, we found a high prevalence of colorectal neoplasia among some populations. This indicates a need to expand CRC screening programs for these groups. The pooled prevalence estimates can be used as quality indicators for established CRC screening programs.

Young-Onset Early Colorectal Cancer Had Similar Relative Survival to but Better Overall Survival Than Conventional Early Colorectal Cancer: A Large Population-Based Study

Background: There existed limited evidence about prognosis of young-onset early colorectal cancer (ECRC). In the present study, we aimed to compare prognosis between patients with young-onset ECRCs and patients with conventional ECRCs.

Method: Patients with surgically resected, histologically diagnosed ECRCs were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. Young-onset ECRC was defined as ECRC occurring in patients aged <50 years. Five-years relative survival was calculated at the time of diagnosed year and linear regression was performed to analyze the association between 5-years relative survival and age. The multivariate Cox regression, multivariate competing risk model, and propensity score matching (PSM) and univariate analysis weighted by the inverse probability of treatment weight (IPTW) were used to compare overall survival (OS) between young-onset ECRCs and conventional ECRCs.

Results: A total of 51,197 ECRCs were retrieved from SEER database, including 4,634 young-onset ECRCs and 46,563 conventional ECRCs. Five-years relative survival was found to be moderately associated with different age groups (R = −0.725, P = 0.0034). Patients with young-onset ECRCs (96.7%) had similar 5-years relative survival compared with conventional ECRCs (96.3%). However, multivariate Cox regression [HR (hazard ratio), 0.18; 95% CI: 0.16–0.20; P < 0.001] showed better OS in young-onset ECRCs. After PSM, we still found favored prognosis for young-onset ECRCs under univariate Cox regression (HR, 0.18; 95% CI: 0.16–0.21; P < 0.001). Similar results could also be found in the univariate Cox regression weighted by IPTW (HR, 0.17; 95% CI: 0.17–0.18; P < 0.001).

Conclusions: Patients with young-onset ECRCs had similar relative survival but better OS compared with conventional ECRCs.

Caffeine and its main targets of colorectal cancer

Caffeine is a purine alkaloid and is widely consumed in coffee, soda, tea, chocolate and energy drinks. To date, a growing number of studies have indicated that caffeine is associated with many diseases including colorectal cancer. Caffeine exerts its biological activity through binding to adenosine receptors, inhibiting phosphodiesterases, sensitizing calcium channels, antagonizing gamma-aminobutyric acid receptors and stimulating adrenal hormones. Some studies have indicated that caffeine can interact with signaling pathways such as transforming growth factor β, phosphoinositide-3-kinase/AKT/mammalian target of rapamycin and mitogen-activated protein kinase pathways through which caffeine can play an important role in colorectal cancer pathogenesis, metastasis and prognosis. Moreover, caffeine can act as a general antioxidant that protects cells from oxidative stress and also as a regulatory factor of the cell cycle that modulates the DNA repair system. Additionally, as for intestinal homeostasis, through the interaction with receptors and cytokines, caffeine can modulate the immune system mediating its effects on T lymphocytes, B lymphocytes, natural killer cells and macrophages. Furthermore, caffeine can not only directly inhibit species in the gut microbiome, such as Escherichia coli and Candida albicans but also can indirectly exert inhibition by increasing the effects of other antimicrobial drugs. This review summarizes the association between colorectal cancer and caffeine that is being currently studied.

KDM4B facilitates colorectal cancer growth and glucose metabolism by stimulating TRAF6-mediated AKT activation

Background

Histone lysine demethylase 4B (KDM4B) has been implicated in various pathological processes and human diseases. Glucose metabolism is the main pattern of energy supply in cells and its dysfunction is closely related to tumorigenesis. Recent study shows that KDM4B protects against obesity and metabolic dysfunction. We realized the significant role of KDM4B in metabolism. However, the role of KDM4B in glucose metabolism remains unclear. Here, we sought to delineate the role and mechanism of KDM4B in glucose metabolism in colorectal cancer (CRC).

Methods

We first analyzed the role of KDM4B in glucose uptake and CRC growth. We then investigated the consequences of KDM4B inhibition on the expression of GLUT1 and AKT signaling, also explored the underlying mechanism. Finally, we detected the mechanism in vivo and assessed the potential correlation between the expression of KDM4B and CRC prognosis.

Results

We found that KDM4B promoted glucose uptake and ATP production by regulating the expression of GLUT1 via the AKT signaling pathway. KDM4B could interact with TRAF6 and promote TRAF6-mediated ubiquitination of AKT for AKT activation. Furthermore, we demonstrated that KDM4B was overexpressed in CRC specimens and high level of KDM4B was associated with a poor survival rate in CRC patients.

Conclusions

These findings reveal that KDM4B plays an important role in promoting CRC progression by enhancing glucose metabolism.

Colorectal screening using the immunochemical faecal occult blood test kit among the Malaysian cohort participants

BACKGROUND

There has been a rapid increase in colorectal cancer (CRC) cases in Asian countries, including Malaysia. CRC is usually diagnosed at a late stage, and early detection of CRC is vital in improving survival. This study was conducted to determine the uptake rate of the immunochemical faecal occult blood test (iFOBT), the response rate to colonoscopy, and the CRC detection rate. We also wanted to identify the association between colorectal neoplasia and the Asia Pacific Colorectal Cancer Screening (APCS) scoring system.

METHODS

We recruited 2264 individuals from The Malaysian Cohort participants aged 35-65 years who consented to colorectal screening using the iFOBT kit from July 2017 until January 2019.

RESULTS

The response rate and positive iFOBT test rate of this study were 79.6% and 13.1% respectively. Among those with positive results, 125 individuals (52.7%) underwent colonoscopy; CRC was detected in six of them while 45 others (36.0%) had polyps. The overall CRC detection rate was 0.3% while the colorectal neoplasia detection rate (both colorectal cancer and colorectal polyps) was 2.3%. The APCS scoring indicated a significant association with colorectal neoplasia risk, with increasing trend by severity from moderate to high risk (3.46-11.14) compared to low risk. Most of the participants who were positive for iFOBT were those at high risk.

CONCLUSIONS

The awareness of CRC risk and iFOBT screening are important strategies for early detection of CRC. We showed a CRC detection rate of 0.3 % among those who volunteered to have the iFOBT screening.

Qualitative faecal immunochemical tests (FITs) for diagnosing colorectal cancer in patients with histories of rectal bleeding in primary care: a cohort study

BACKGROUND

Rectal bleeding is considered an alarm symptom for colorectal cancer (CRC) but it is common and mostly caused by benign conditions. Qualitative faecal immunochemical tests (FITs) for occult blood have been used as diagnostic aids for many years in Sweden when CRC is suspected. The study aimed to evaluate the usefulness of FITs requested by primary care physicians for patients with and without histories of rectal bleeding, in the diagnosis of CRC.

METHODS

Results of all FITs requested in primary care for symptomatic patients in the Örebro region during 2015 were retrieved. Data on each patient's history of rectal bleeding was gathered from electronic health records. Patients diagnosed with CRC within 2 years were identified from the Swedish Cancer Register. The analysis focused on three-sample FITs, the customary FIT in Sweden.

RESULTS

A total of 4232 patients provided three-sample FITs. Information about the presence/absence of rectal bleeding was available for 2027 patients, of which 59 were diagnosed with CRC. For 606 patients with the presence of rectal bleeding, the FIT showed sensitivity 96.2%, specificity 60.2%, positive predictive value 9.8% (95% CI 6.1-13.4) and negative predictive value 99.7% (95% CI 99.2-100) for CRC. For 1421 patients without rectal bleeding, the corresponding figures were 100%, 73.6%, 8.3% (95% CI 5.6-10.9) and 100% (95% CI 99.6-100).

CONCLUSION

The diagnostic performance of a qualitative three-sample FIT provided by symptomatic patients in primary care was similar for those with and without a history of rectal bleeding. FITs seem useful for prioritising patients also with rectal bleeding for further investigation.

Genomics and metagenomics of colorectal cancer

Colorectal cancer (CRC) is a common cancer globally. It is a complex disease influenced by genetic and environmental factors. Early studies on familial cases have identified major genes involved in CRC, such as proto-oncogenes KRAS, PIK3CA and BRAF, and tumour-suppressor genes APC and TP53. These genes have provided valuable insight into the molecular pathogenesis of CRC, and some have made ways to clinical utility to help diagnose cancer syndromes, prognosticate oncological outcomes and predict treatment responses. While these genetic factors are important, recent studies have suggested contribution of microorganisms to colorectal carcinogenesis. Observational studies, animal experiments and translational works have identified several microorganisms as potential carcinogenic bacteria, such as Fusobacterium nucleatum and Peptostreptococcus anaerobius. With the advent of sequencing technology and bioinformatics, more genomic and metagenomic factors are being uncovered as important players in CRC carcinogenesis. This article aims to review recent genomic and metagenomic discoveries relating to CRC.

Development of a risk score for colorectal cancer in Chinese males: A prospective cohort study

To build a simple predictive model as a guide to stratify average‐risk population for colonoscopy examinations. We collected data from 92 923 males without a prior history of cancer enrolled in the Kailuan Cohort Study of China. Risk factors included in the evaluation of colorectal cancer (CRC) were collected by questionnaire‐based interviews at the baseline. Logistic regression coefficients for incident CRC predictors were converted into risk scores by the absolute value of the smallest coefficient in the model and rounding up to the nearest integer. Receiver operating characteristic (ROC) analysis with the leave‐one‐out cross‐validation method was applied to evaluate model performance. In the 10‐year follow‐up, 353 CRC patients were in the cohort. Age, alcohol consumption, waist circumference, occupational sitting time, and history of diabetes were selected for the scoring system, and the adjusted area under the ROC was 0.66. Population in the highest risk group (16‐19 points) had a 33.12‐fold (95% CI: 13.44‐81.59) higher risk of CRC than those in the lowest risk group. When we defined 13 points as the cut‐off, the sensitivity and specificity of the scoring system for CRC were 67.99% and 62.42%, respectively. A simple scoring system for CRC has been developed to identify men at an increased relative risk of CRC within 10 years using several well‐established risk factors, which allows selection of asymptomatic candidates for priority of CRC screening and saving the health resource in cancer prevention and control.

Enhancing bowel screening: Preventing colorectal cancer by flexible sigmoidoscopy in New Zealand

OBJECTIVES

The prevention of colorectal cancer (CRC) attainable from introducing once-in-a-lifetime flexible sigmoidoscopy (FSIG) screening was assessed.

STUDY DESIGN

This is a review of relevant available information for the assessment of the impact and resource demands of FSIG in New Zealand.

METHODS

The reduction in bowel cancer incidence achievable by one-off FSIG screening from 50 to 59 years of age, an age group for which bowel screening is not currently offered, was reviewed. The prevention of CRC attainable from an offer of screening at 55 years of age in New Zealand was also estimated. The number and cost of the FSIG screening procedures required and referrals for colonoscopies and the savings in treatment were calculated.

RESULTS

Annually, about 27,500 FSIG screening procedures would be required if 50% of those turning 55 years of age accepted an offer of once-in-a-lifetime FSIG screening. This would result in three-four-fold fewer people being referred for colonoscopy than in the national 2-yearly faecal immunochemical test (FIT) screening programme and subsequently reduce demand for colonoscopy from a false-positive FIT. The number of CRC cases prevented would increase over 17 years to more than 300 per year by 2033. After 10-15 years of screening, the annual savings in health service costs, primarily from CRC prevented, were sufficient to completely fund the FSIG screening.

CONCLUSIONS

Inclusion of FSIG screening in the national bowel screening programme would significantly reduce both the incidence and mortality of CRC in New Zealand, reduce the colonoscopy demand of current bowel screening and reduce long-term health service costs.

POTEE drives colorectal cancer development via regulating SPHK1/p65 signaling

Aberrant gene expression plays critical roles in the development of colorectal cancer (CRC). Here we show that POTEE, which was identified as a member E of POTE ankyrin domain family, was significantly upregulated in colorectal tumors and predicted poor overall survival of CRC patients. In CRC cells, POTEE could act as an oncogene and could promote cell growth, cell-cycle progression, inhibit apoptosis, and elevates xenograft tumor growth. Mechanically, we used microarray analysis and identified a POTEE/SPHK1/p65 signaling axis, which affected the biological functions of CRC cells. Further evaluation showed that overexpression of POTEE could increase the protein expression of SPHK1, followed by promoting the phosphorylation and activation of p65 protein. Altogether, our findings suggested a POTEE/SPHK1/p65 signaling axis could promote colorectal tumorigenesis and POTEE might potentially serve as a novel biomarker for the diagnosis and an intervention of colorectal cancer.

Socio-cognitive determinants of colorectal cancer screening uptake: An application of intervention mapping approach

Background: Fecal occult blood test (FOBT) is one of the common screening tests for colorectal cancer. This study was designed to determine the socio-cognitive determinants related to FOBT uptake for colorectal cancer screening based on intervention mapping (IM).

Methods: A total of 500 individuals aged over 50 years were randomly selected to participate in this study in Kermanshah, Iran, in 2016. Data were collected by interviews based on a questionnaire and analyzed by SPSS16 using bivariate correlation, linear, and logistic regression models.

Results: Of the 500 respondents, 468 (93.6%) signed the consent form and voluntarily participated in the study. Almost 11.1% of the participants had a history of FOBT uptake. Socio-cognitive variables accounted for 38% of the variation in the outcome measure of the intention to uptake FOBT. Perceived self-efficacy (OR = 3.345 & 95% CI: 1.342, 8.339), perceived susceptibility (OR = 2.204& 95% CI: 1.320, 3.680), attitude (OR = 1.674& 95% CI: 1.270, 2.137), and perceived severity (OR = 1.457& 95% CI: 0.954, 2.224) were the strongest predictors of fecal occult blood test uptake.

Conclusion: IM-based analysis of behavior may provide insights to design interventions for modifying individuals’ beliefs about the usefulness of FOBT uptake to prevent colorectal cancer.

Response gene to complement 32 expression in macrophages augments paracrine stimulation-mediated colon cancer progression

M2-polarized tumor associated macrophages (TAMs) play an important role in tumor progression. It has been reported that response gene to complement 32 (RGC-32) promotes M2 macrophage polarization. However, whether RGC-32 expression in macrophages could play a potential role in tumor progression remain unclear. Here we identified that increasing RGC-32 expression in colon cancer and tumor associated macrophages was positively correlated with cancer progression. In vitro studies confirmed that colon cancer cells upregulated RGC-32 expression of macrophages via secreting TGF-β1. RGC-32 expression promoted macrophage migration. In addition, stimulation of HCT-116 cells with the condition mediums of RGC-32-silienced or over-expressed macrophages affected tumor cell colony formation and migration via altered COX-2 expression. In an animal model, macrophages with RGC-32 knockdown significantly decreased the expression of COX-2 and Ki67 in the xenografts, and partly inhibited tumor growth. Together, our results provide the evidences for a critical role of TGF-β1/RGC-32 pathway in TAMs and colon cancer cells during tumor progression.