Screening and surveillance for the early detection of colorectal cancer and adenomatous polyps, 2008: a joint guideline from the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Radiology

Glycosylation Profiling of Tumor Marker in Plasma Using Bead-Based Immunoassay

As one of the most important posttranslational modifications, glycosylation plays critical roles in protein folding, trafficking, cell differentiation, immune recognition, etc. The alteration of glycosylation is closely associated with the pathological processes during and after caner development, and thus holds great value in cancer detection. In this chapter, we describe a protocol on the glycosylation profiling of tumor marker in plasma using bead-based immunoassay with CA125 as a model, including bead coupling, coupling control, glycosylation assay, as well as the plasma screening for breast cancer patients. This protocol can be used to profile the glycosylation of protein markers in clinical plasma or serum samples for different human cancers.

Endoscopist Specialty Predicts the Likelihood of Recommending Cessation of Colorectal Cancer Screening in Older Adults

OBJECTIVES

Although the 2008 US Preventive Services Task Force guidelines recommend against routine colorectal cancer (CRC) screening for adults aged 76-85, it is unclear what endoscopists recommend in practice. Our goal was to examine current practice around cessation of CRC screening in older adults.

METHODS

We included normal screening colonoscopy exams in adults ≥ 50 years old within the New Hampshire Colonoscopy Registry between 2009 and 2014. The primary outcome was endoscopists' recommendation against further screening. The main exposure variables included patient age, family history of CRC, and endoscopist characteristics. Descriptive statistics and univariate and multivariable logistic regression models were used.

RESULTS

Of 13,364 normal screening colonoscopy exams, 2914 (21.8%) were in adults aged ≥ 65 and were performed by 74 endoscopists. Nearly 100% of adults aged 65-69 undergoing screening colonoscopy were given the recommendation to return for screening colonoscopy in the future. Only 15% of average-risk patients aged 70-74 were told to stop receiving screening, while 85% were told to return at a future interval, most frequently in 10 years when they would be 80-84. In the multivariable model, advancing patient age and the absence of family history of CRC were significantly associated with a recommendation to stop colonoscopy. Gastroenterologists were more likely to recommend stopping colonoscopy in accordance with guidelines than other non-gastroenterology endoscopists (adjusted OR (95% CI) 2.3 (1.6-3.4)).

CONCLUSIONS

In a large statewide colonoscopy registry, the majority of older adults are told to return for future screening colonoscopy. Having a family history of CRC or a non-gastroenterology endoscopist increases the likelihood of being told to return for screening at advanced ages.

Diagnostic Potential and Interactive Dynamics of the Colorectal Cancer Virome

Colorectal cancer is a leading cause of cancer-related death in the United States and worldwide. Its risk and severity have been linked to colonic bacterial community composition. Although human-specific viruses have been linked to other cancers and diseases, little is known about colorectal cancer virus communities. We addressed this knowledge gap by identifying differences in colonic virus communities in the stool of colorectal cancer patients and how they compared to bacterial community differences. The results suggested an indirect role for the virome in impacting colorectal cancer by modulating the associated bacterial community. These findings both support the idea of a biological role for viruses in colorectal cancer and provide a new understanding of basic colorectal cancer etiology.

Human viruses (those that infect human cells) have been associated with many cancers, largely due to their mutagenic and functionally manipulative abilities. Despite this, cancer microbiome studies have focused almost exclusively on bacteria instead of viruses. We began evaluating the cancer virome by focusing on colorectal cancer, a primary cause of morbidity and mortality throughout the world and a cancer linked to altered colonic bacterial community compositions but with an unknown association with the gut virome. We used 16S rRNA gene, whole shotgun metagenomic, and purified virus metagenomic sequencing of stool to evaluate the differences in human colorectal cancer virus and bacterial community composition. Through random forest modeling, we identified differences in the healthy and colorectal cancer viromes. The cancer-associated virome consisted primarily of temperate bacteriophages that were also predicted to be bacterium-virus community network hubs. These results provide foundational evidence that bacteriophage communities are associated with colorectal cancer and potentially impact cancer progression by altering the bacterial host communities.

Quantitative analysis of in vivo high-resolution microendoscopic images for the detection of neoplastic colorectal polyps

Colonoscopy is routinely performed for colorectal cancer screening but lacks the capability to accurately characterize precursor lesions and early cancers. High-resolution microendoscopy (HRME) is a low-cost imaging tool to visualize colorectal polyps with subcellular resolution. We present a computer-aided algorithm to evaluate HRME images of colorectal polyps and classify neoplastic from benign lesions. Using histopathology as the gold standard, clinically relevant features based on luminal morphology and texture are quantified to build the classification algorithm. We demonstrate that adenomatous polyps can be identified with a sensitivity and specificity of 100% and 80% using a two-feature linear discriminant model in a pilot test set. The classification algorithm presented here offers an objective framework to detect adenomatous lesions in the colon with high accuracy and can potentially improve real-time assessment of colorectal polyps.

Prolonged Cecal Insertion Time Is Not Associated with Decreased Adenoma Detection When a Longer Withdrawal Time Is Achieved

BACKGROUND

The association between withdrawal time and adenoma detection has been established; however, the effect of cecal insertion time on adenoma detection remains unclear.

AIM

To determine the association between cecal insertion time and adenoma detection.

METHODS

This study completed a retrospective analysis of data collected in 4 prospective randomized-controlled trials related to screening and surveillance colonoscopy at a single tertiary care from 2010 to 2016. The primary outcome was cecal insertion time and its association with mean number of adenomas per patient and adenoma detection rate (ADR).

RESULTS

1303 patients met inclusion criteria (average age 59.7 ± 8.7 years; 759 females (58.3%), and 763 Caucasians (58.6%). Mean cecal insertion time was significantly longer in patients who were female (p < 0.001), received moderate sedation (p = 0.001), had fellow involvement (p < 0.001), older (p = 0.002), and lower Boston bowel preparation scale (p < 0.001). Withdrawal time was found to increase as mean cecal insertion time increased (p < 0.001). The mean cecal insertion time was not different in patients with or without adenomas (p = 0.94). Cecal insertion time did not correlate with the mean number of adenomas or advanced adenomas per patient (p > 0.05), which was also true on Poisson regression analysis. Adenomas and advanced adenomas per patient were found to decrease when cecal insertion to withdrawal time ratios were greater than 1 (p < 0.001).

CONCLUSIONS

Prolonged cecal insertion time was not associated with a decrease in ADR, mean number of adenomas or advanced adenomas per patient. When withdrawal times were longer than cecal insertion times, the number of adenomas and advanced adenomas detected per patient was significantly improved.

The Effect of Educational Intervention Based on Health Belief Model and Social Support on the Rate of Participation of Individuals in Performing Fecal Occult Blood Test for Colorectal Cancer Screening

Background and Aim: Among the screening tests for colorectal cancer, fecal occult blood test (FOBT) is important in comparison other methods due to its ease of use and low cost.The aim of this study is to survey the effect of educational intervention based on health belief model and social support on the rate of participation of individuals in performing fecal occult blood test for colorectal cancer screening among men who referred to the health centers in FasaCity, Fars province, Iran. Materials and Methods: In this quasi-experimental study, 200 men (100 in experimental group and 100 in control group) in FasaCity, Fars province, Iranwere selected in 2017. A questionnaire consisting of demographic information, knowledge, HBM constructs (perceived susceptibility, severity, benefits, barriers, self- efficacy and cues to action) and social support was used to measure the rate of participation of individuals in performing Fecal Occult Blood Test for colorectal cancer screening before and three months after the intervention. Data were analyzed using SPSS22 viadescriptive and inferential statistics, paired t-test, Mann-Whitney, Chi-square, and independent t-test at a significance level of 0.5. Results: The mean age of the men was 63.18 ± 8.25 years in the experimental group and 65.11 ± 7.66 years in the control group. Three months after the intervention, the experimental group showed a significant increase in the knowledge, perceived susceptibility, perceived severity, perceived benefits, Self-efficacy, cues to action, social support and the level of referrals (participation) of subjects for FOBTcompared to the control group. Conclusion: This study showed the effectiveness of HBM constructs and social support in adoption of the level of participation of subjects for FOBTin men. Hence, these models can act as a framework for designing and implementing educational interventions for undergoing FOBT.

Does Hyoscine improve polyp detection rate during colonoscopy? Systematic Review & meta-analysis of randomized clinical trials

BACKGROUND/OBJECTIVE

Published studies have shown conflicting results regarding the benefit of Hyoscine Butylbrmoide use during colonoscopy in polyp and adenoma detection rates. This meta-analysis was conducted with the aim to summarize all available evidence.

METHODS

A literature search was carried out using PubMed, Ovid MEDLINE and the Cochrane Library database from inception to December 2017. Studies that compared the use of Hyoscine Butylbrmoide compared to placebo during colonoscopy were included. Pooled odds ratio and 95% confidence interval were calculated using Mantel-Haenszel fixed-effects model when there was no heterogeneity identified.

RESULTS

Of the 423 retrieved studies, eight met the eligibility criteria and were included in the analysis. There was no significant difference between the groups in terms of polyp and adenoma detection rates.There was no significant difference between the Hyoscine and placebo groups in polyp detection rate (49.3% vs 48%, OR = 1.06, 95% CI: 0.90-1.23, P = 0.50). Adenoma detection rate was also not significantly different between the 2 groups 33.7% vs, 31%; OR = 1.13; 95%CI: 0.95-1.35; P = 0.16). No heterogeneity was observed (P = 0.65, I² = 0%).

CONCLUSION

This meta-analysis found no significant impact of Hyoscine on polyp and adenoma detection when used during colonoscopy.

Usefulness of both PET/CT with F18-FDG and whole-body diffusion-weighted imaging in cancer screening: a preliminary report

OBJECTIVE

Positron emission tomography/computed tomography (PET/CT) with fluorodeoxyglucose (F18-FDG) is useful for the detection of malignant lesions, including metastatic lesions, and this technique is widely used in cancer screening. However, this approach may occasionally yield false-positive and false-negative findings. At our PET center, to increase the accuracy of PET/CT, we use PET/CT and whole-body diffusion-weighted imaging (WB-DWI) together. This study aimed to assess the usefulness of this combination.

METHODS

We examined 29 subjects with confirmed diagnosis. All of them had undergone PET/CT and WB-DWI on the same day. Twenty-seven of them also underwent ultrasonography, blood testing, and upper gastrointestinal series on the same day and two fecal occult blood tests on another day. WB-DWI was performed on a 1.5-T MRI unit with a b value of 0 and 800 or 1000 s/mm². For all 29 cases, PET/CT and WB-DWI were classified to be positive or negative, and the diagnostic ability was calculated for each modality.

RESULTS

Among the 29 subjects, 17 had malignant tumors and 12 had benign tumors or no abnormalities. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET/CT were 65%, 25%, 55%, 33%, and 48%, respectively; while the corresponding values for WB-DWI were 59%, 100%, 100%, 63%, and 76%, respectively. By considering the result to be negative when PET/CT findings were positive but WB-DWI findings were negative, specificity increased from 25 to 100%, and accuracy increased from 48 to 76%. On the other hand, by considering the result to be positive when the findings of either PET/CT or WB-DWI were positive, sensitivity increased from 65 to 76%, and accuracy increased from 48 to 55%.

CONCLUSIONS

Our results suggest that using both PET/CT and WB-DWI together can increase accuracy in cancer screening. However, this approach was not able to detect malignant lesions in some cases, indicating that there were limitations with imaging certain organs. Therefore, it is important to further understand the features of PET/CT and WB-DWI and use them appropriately for each organ. Additionally, given that the study sample was relatively small, further research is needed to validate these findings.

Efficacy and safety of chemopreventive agents on colorectal cancer incidence and mortality: systematic review and network meta-analysis

Background

Various interventions have been tested as primary prevention of colorectal cancers (CRC), but comprehensive evidence comparing them is absent. We examined the effects of various chemopreventive agents (CPAs) on CRC incidence and mortality.

Methods

We did a network meta-analysis based on a systematic review of randomized controlled trials (RCTs) that compared at least one CPA (aspirin, antioxidants, folic acid, vitamin B6, vitamin B12, calcium, vitamin D, alone or in combination) to placebo or other CPA in persons without history of CRC. Several databases were searched from inception up to March 2017. Primary outcomes were early and long-term CRC incidence and mortality.

Results

Twenty-one RCTs comprising 281,063 participants, 9 RCTS comprising 160,101 participants, and 7 RCTs comprising 24,001 participants were included in the network meta-analysis for early risk of CRC incidence, long-term risk of CRC incidence and mortality, respectively. For early CRC incidence, no CPAs were found to be effective. For long-term CRC incidence and mortality, aspirin was the only intervention that showed protective effects with potential dose-dependent effects (risk ratio [RR], 0.74 [95% CI, 0.57–0.97] for high-dose [≥325 mg/day] and RR, 0.81 [95% CI, 0.67–0.98] for very-low-dose [≤100 mg/day]). Similar trend was found for mortality (RR, 0.43 [95% CI, 0.23–0.81] for low-dose [>100–325 mg/day] and RR, 0.65 [95% CI, 0.45–0.94] for very-low-dose). However, in net clinical benefit analysis, when combining risk estimates on mortality from CRC, cardiovascular disease, and pooled risk estimates of major gastrointestinal bleeding, low-dose aspirin provided the highest net survival gain (%) of 1.736 [95% CI, 1.010–2.434].

Conclusion

Aspirin at the dose range of 75–325 mg/day is a safe and effective primary prevention for long-term CRC among people at average risk. None of the other CPAs were found to be effective. There may potentially be differential effects among various doses of aspirin that needs further investigation.

Rare loss of function variants in candidate genes and risk of colorectal cancer

Although ~ 25% of colorectal cancer or polyp (CRC/P) cases show familial aggregation, current germline genetic testing identifies a causal genotype in the 16 major genes associated with high penetrance CRC/P in only 20% of these cases. As there are likely other genes underlying heritable CRC/P, we evaluated the association of variation at novel loci with CRC/P. We evaluated 158 a priori selected candidate genes by comparing the number of rare potentially disruptive variants (PDVs) found in 84 CRC/P cases without an identified CRC/P risk-associated variant and 2440 controls. We repeated this analysis using an additional 73 CRC/P cases. We also compared the frequency of PDVs in select genes among CRC/P cases with two publicly available data sets. We found a significant enrichment of PDVs in cases vs. controls: 20% of cases vs. 11.5% of controls with ≥ 1 PDV (OR = 1.9, p = 0.01) in the original set of cases. Among the second cohort of CRC/P cases, 18% had a PDV, significantly different from 11.5% (p = 0.02). Logistic regression, adjusting for ancestry and multiple testing, indicated association between CRC/P and PDVs in NTHL1 (p = 0.0001), BRCA2 (p = 0.01) and BRIP1 (p = 0.04). However, there was no significant difference in the frequency of PDVs at each of these genes between all 157 CRC/P cases and two publicly available data sets. These results suggest an increased presence of PDVs in CRC/P cases and support further investigation of the association of NTHL1, BRCA2 and BRIP1 variation with CRC/P.

Detection of serrated lesions in proximal colon by simulated sigmoidoscopy vs faecal immunochemical testing in a multicentre, pragmatic, randomised controlled trial

Background

The diagnostic yield of the faecal immunochemical test and sigmoidoscopy in detecting proximal serrated polyps in a colorectal cancer screening programme has not been fully assessed.

Aim

We determined the detection rate of proximal serrated polyps by simulated sigmoidoscopy and faecal immunochemical test compared with total colonoscopy in a population-based, multicentre, nationwide, randomised controlled trial (ColonPrev study).

Methods

Sigmoidoscopy yield was simulated based on the UK-Flexible Sigmoidoscopy Trial for total colonoscopy referral. Definitions were: proximal serrated polyp (proximal serrated polyp): sessile serrated polyp or hyperplastic polyp of any size and proximal at-risk serrated polyp (at-risk proximal serrated polyp): sessile serrated polyp of any size or hyperplastic polyp ≥ 10 mm, both located proximally to the splenic flexure.

Results

A total of 10,611 individuals underwent faecal immunochemical test and 5059 underwent total colonoscopy and were evaluated by simulated sigmoidoscopy. Sigmoidoscopy and faecal immunochemical test were less accurate in detecting proximal serrated polyps (odds ratio: 0.13; 95% confidence interval: 0.10-0.18 and 0.13; 0.09-0.18, p < 0.0001, respectively). Both tests were inferior to colonoscopy in detecting at-risk proximal serrated polyps, and sigmoidoscopy was inferior to faecal immunochemical test in detecting these lesions (odds ratio: 0.17; 95% confidence interval: 0.10-0.30 and 0.25; 0.17-0.37, p < 0.0001, respectively).

Conclusion

Sigmoidoscopy and faecal immunochemical test are less accurate in detecting proximal serrated polyps than colonoscopy, particularly in women.

Rotating night shift work and colorectal cancer risk in the nurses' health studies

Animal and human data have suggested that shift work involving circadian disruption may be carcinogenic for humans, but epidemiological evidence for colorectal cancer remains limited. We investigated the association of rotating night shift work and colorectal cancer risk in two prospective female cohorts, the Nurses' Health Study (NHS) and NHS2, with 24 years of follow‐up. In total, 190,810 women (NHS = 77,439; NHS2 = 113,371) were included in this analysis, and 1,965 incident colorectal cancer cases (NHS = 1,527; NHS2 = 438) were reported during followup (NHS: 1988–2012, NHS2: 1989–2013). We used Cox proportional hazards models adjusted for a wide range of potential confounders. We did not observe an association between rotating night work duration and colorectal cancer risk in these cohorts (NHS: 1–14 years: Hazard Ratio (HR) 1.04, 95% CI: 0.94, 1.16; 15+ years: HR 1.15, 95% CI: 0.95, 1.39; P_trend = 0.14 and NHS2: 1–14 years: HR 0.81, 95% CI: 0.66, 0.99; 15+ years: HR 0.96, 95% CI: 0.56, 1.64 and P_trend = 0.88). In subsite analysis in NHS, rectal cancer risk increased after long‐term (15+ years) rotating night shift work (proximal colon cancer: HR 1.00, 95% CI: 0.75, 1.34, P_trend = 0.90; distal colon cancer: HR 1.27, 95% CI: 0.87, 1.85, P_trend = 0.32; rectal cancer: HR 1.60, 95% CI: 1.09, 2.34, P_trend = 0.02). We found no overall evidence of an association between rotating night shift work and colorectal cancer risk in these two large cohorts of nurses. Risk for rectal cancer significantly increased with shift work duration, suggesting that long‐term circadian disruption may play a role in rectal cancer development.

What's new?

Night shift work is associated with circadian rhythm disruption, sleep deprivation, and lifestyle changes. Circadian disruption in particular can lead to the deregulation of basic cellular functions, including DNA damage repair, and thus is potentially carcinogenic in humans. In the present study, involving two large prospective cohorts of nurses, no overall evidence of an association was detected between rotating night shift work and colorectal cancer risk. Risk for rectal cancer increased significantly, however, with long‐term rotating night shift work, lasting 15 or more years, suggesting that long‐term circadian disruption may play a role in rectal cancer development.

Incidence patterns of colorectal cancers in four countries of the Middle East Cancer Consortium (Cyprus, Jordan, Israel, and İzmir, Turkey) compared with those in the United States Surveillance, Epidemiology, and End Results Program

BACKGROUND/AIMS

There are wide variations in colorectal cancer (CRC) incidence across the world. Historically, the highest incidence rates have been reported historically in more developed countries; however, increasing trends have been seen in developing countries. Here, we present the CRC incidence pattern in Cyprus, Israel, Jordan, and İzmir, Turkey, which are countries of the Middle East Cancer Consortium (MECC).

MATERIALS AND METHODS

We analyzed 2005-2010 CRC data from population-based registries and calculated crude and age standardized rates for CRC, colon and rectum subsites, and annual percent changes (APCs) for trends.

RESULTS

The age-adjusted incidence rates (AAIRs) for CRC were the highest in Israeli Jews (IJ) (46.7 for males and 35.5 for females), which exceeded those of the USA Surveillance, Epidemiology, and End Result (SEER) program registries. In both sexes, AAIRs in Cyprus and Israeli Arabs (IA) were close to those in SEER registries. For both sexes, AAIRs in İzmir and Jordan were substantially lower than those in other registries. Statistically significant decreasing trends over time were observed in AAIRs for both sexes in the SEER program (APCs: males, -3.24% and females, -2.54%), whereas the trends varied within the MECC registries. There were decreasing AAIR trends for males in IJ and IA and for females in Cyprus and IJ; APC for females in IJ (-4.29%) was significant. Conversely, increasing trends with the significant APCs were observed in males in İzmir (2.43%) and Jordan (7.57%).

CONCLUSION

MECC countries comprise both high- and low-risk populations for CRCs. However, increasing trends in low-risk populations have been alarming. Thus, the need for implementing tailored primary and secondary prevention programs in the region is essential.

Uptake of the English Bowel (Colorectal) Cancer Screening Programme: an update 5 years after the full roll-out

Background

The initial roll-out of the English Bowel (Colorectal) Cancer Screening programme, during 2006 and 2009, found uptake to be low (54%) and socially graded. The current analysis used data from 2010 to 2015 to test whether uptake is increasing and becoming less socially graded over time.

Methods

Postcode-derived area-level uptake of 4.4 million first-time invitees, stratified by gender and the year of the first invitation (2010–2015), was generated using the National Bowel Cancer Screening System. Data were limited to people aged 60–64 years. Binomial regression tested for variations in uptake by the year of invitation, gender, region, area-based socio-economic deprivation and area-based ethnic diversity.

Results

Overall, the first-time colorectal cancer (CRC) screening uptake across 6 years was 52% (n = 2,285,996/4,423,734) with a decline between 2010 and 2015 (53%, 54%, 52%, 50%, 49%, 49% respectively). Uptake continued to be socially graded between the most and the least deprived area-level socio-economic deprivation quintiles (43% vs 57%), the most and the least area-based ethnic diversity quintiles (41% vs 56%) and men and women (47% vs 56%). Multivariate analysis demonstrated the effects of year, deprivation, ethnicity and gender on uptake. The effect of deprivation was more pronounced in the most deprived area quintile between men and women (40% vs 47%) than the least deprived area quintile (52% vs 62% respectively).

Conclusion

We did not find evidence of change in uptake patterns in CRC screening since its initial launch 10 years ago. The programme is unlikely to realise its full public health benefits and is en route to widening inequalities in CRC outcomes.

•

Colorectal cancer screening uptake among first-time invitees remains low at 52%.

•

There is a worrying reduction in colorectal cancer screening uptake between 2010 and 2015.

•

There is no evidence that the social inequalities in uptake have reduced over time.

•

There is no evidence of diffusion of innovation in colorectal cancer screening uptake in England.

A Randomized Trial to Compare a Tailored Web-Based Intervention and Tailored Phone Counseling to Usual Care for Increasing Colorectal Cancer Screening

BACKGROUND

Colorectal cancer mortality could be decreased with risk-appropriate cancer screening. We examined the efficacy of three tailored interventions compared with usual care for increasing screening adherence.

METHODS

Women (n = 1,196) ages 51 to 74, from primary care networks and nonadherent to colorectal cancer guidelines, were randomized to (1) usual care, (2) tailored Web intervention, (3) tailored phone intervention, or (4) tailored Web + phone intervention. Average-risk women could select either stool test or colonoscopy, whereas women considered at higher than average risk received an intervention that supported colonoscopy. Outcome data were collected at 6 months by self-report, followed by medical record confirmation (attrition of 23%). Stage of change for colorectal cancer screening (precontemplation or contemplation) was assessed at baseline and 6 months.

RESULTS

The phone (41.7%, P < 0.0001) and combined Web + phone (35.8%, P < 0.001) interventions significantly increased colorectal cancer screening by stool test compared with usual care (11.1%), with ORs ranging from 5.4 to 6.8 in models adjusted for covariates. Colonoscopy completion did not differ between groups except that phone significantly increased colonoscopy completion compared with usual care for participants in the highest tertile of self-reported fear of cancer.

CONCLUSIONS

A tailored phone with or without a Web component significantly increased colorectal cancer screening compared with usual care, primarily through stool testing, and phone significantly increased colonoscopy compared with usual care but only among those with the highest levels of baseline fear.

IMPACT

This study supports tailored phone counseling with or without a Web program for increasing colorectal cancer screening in average-risk women.

An integrated study on TFs and miRNAs in colorectal cancer metastasis and evaluation of three co-regulated candidate genes as prognostic markers

Molecular alterations that occur in cancer have the potential to be considered as either cancer biomarkers or targeted therapies or even both. In the presented study, we aimed to elucidate the gene regulatory network of metastatic colorectal cancer using data acquired from microarrays to reach the most common DEGs in colorectal cancer metastasis and find their possible regulatory mechanism by DETFs and DEmiRs. In this regards, seven microarray datasets were employed to assess the most important DEGs, DETFs and DEmiRs in colorectal cancer metastasis. Afterward, GRN based on DETFs and DEmiRs were constructed. Also ARACNE algorithm was used to construct an accurate GRN. GRN was analyzed structurally and then, two DETFs (LEF1 and ETV4) and a less-well known DEG (FABP6) by real time qRT-PCR in 50 patients with colorectal cancer were quantified. The constructed GRN highlighted the importance of some DETFs and DEmiRs in colorectal cancer metastasis. Interestingly the gene expression analysis by qRT-PCR on three candidate genes (LEF1, ETV4 and FABP6) indicated that the three genes were co-expressed in tumor samples, and were significantly associated with metastasis in colorectal cancer. Therefore, our experimental results proved a part of our comprehensive data analysis and system biology results. In summary, according to our empirical study we found the importance of three candidate genes as the potent prognostic factors in colorectal cancer metastasis. Also our study in a holistic insight on gene regulatory mechanism revealed the importance of some gene regulatory factors (DETFs and DEmiRs) and their potential as prognostic factors and/or targets in molecular targeted therapies in colorectal cancer.

Targeted UPLC-MS Metabolic Analysis of Human Faeces Reveals Novel Low-Invasive Candidate Markers for Colorectal Cancer

Low invasive tests with high sensitivity for colorectal cancer and advanced precancerous lesions will increase adherence rates, and improve clinical outcomes. We have performed an ultra-performance liquid chromatography/time-of-flight mass spectrometry (UPLC-(TOF) MS)-based metabolomics study to identify faecal biomarkers for the detection of patients with advanced neoplasia. A cohort of 80 patients with advanced neoplasia (40 advanced adenomas and 40 colorectal cancers) and 49 healthy subjects were analysed in the study. We evaluated the faecal levels of 105 metabolites including glycerolipids, glycerophospholipids, sterol lipids and sphingolipids. We found 18 metabolites that were significantly altered in patients with advanced neoplasia compared to controls. The combinations of seven metabolites including ChoE(18:1), ChoE(18:2), ChoE(20:4), PE(16:0/18:1), SM(d18:1/23:0), SM(42:3) and TG(54:1), discriminated advanced neoplasia patients from healthy controls. These seven metabolites were employed to construct a predictive model that provides an area under the curve (AUC) median value of 0.821. The inclusion of faecal haemoglobin concentration in the metabolomics signature improved the predictive model to an AUC of 0.885. In silico gene expression analysis of tumour tissue supports our results and puts the differentially expressed metabolites into biological context, showing that glycerolipids and sphingolipids metabolism and GPI-anchor biosynthesis pathways may play a role in tumour progression.

Measuring Beliefs Related to Colorectal Cancer Screening Behavior among Iranian Middle-Aged and Elderly: a Psychometric Study

The annual fecal occult blood test is a very important method for colorectal cancer early detection through screening. Our aim was to assess psychometrics of instrument measuring beliefs related to fecal occult blood test uptake among Iranian middle-aged and elderly, based on the theory of planned behavior. This cross-sectional study was performed on 150 middle-aged and elderly who were randomly selected to participate voluntarily in Kermanshah, in the west of Iran. The studied constructs included attitude, subjective norms, perceived behavior control, and behavior intention. Data were analyzed with SPSS software (ver. 21.0). The mean age of the respondents was 59.1 years [SD: 6.73], in the range from 50 to 73. All of the loads of the exploratory factorial analysis were larger than 0.4. KMO was calculated as 0.756. Overall, four factors under investigation accounted for 82% of the variance in the hypothesized model. Cronbach’s alpha for the measured constructs of attitude, subjective norms, perceived behavior control, and behavior intention were 0.92, 0.88, 0.70 and 0.88, respectively. Our findings indicated the final scale to be adequately reliable and valid for measurement of these constructs for prediction of fecal occult blood test uptake among Iranian middle-aged and elderly.

Colorectal Cancer Screening Preferences among Black and Latino Primary Care Patients

Colorectal cancer (CRC) screening rates in the U.S. have historically been lower among blacks and Latinos than whites. The advent of a new stool-based test, Cologuard, calls for research to determine which CRC screening test minority individuals might prefer. Ninety black and Latino patients who had undergone screening colonoscopy were personally educated about four CRC screening tests and subsequently asked about their test preference, attributes that influenced preference, and strength of preference. Cologuard (31.1 %) and colonoscopy (64.4 %) were preferred over computerized tomographic colonography and fecal immunochemical tests. Preference was influenced by distinct test attributes. Individuals who selected Cologuard over colonoscopy were more likely to be >60 and have greater strength of test preference. There was an overriding preference for Cologuard and colonoscopy among black and Latino individuals who had undergone screening colonoscopy. To further improve CRC screening in these populations, patient preferences should guide recommendations.

Patient Factors Associated With Delays in Obtaining Cancer Care in Botswana

Purpose Delays in diagnosis and treatment of cancers can lead to poor survival. These delays represent a multifaceted problem attributable to patient, provider, and systemic factors. We aim to quantify intervals from symptom onset to treatment start among patients with cancer in Botswana and to understand potential risk factors for delay. Patients and Methods From December 2015 to January 2017, we surveyed patients seen in an oncology clinic in Botswana. We calculated proportions of patients who experienced delays in appraisal (between detecting symptoms and perceiving a reason to discuss them with provider, defined as > 1 month), help seeking (between discussing symptoms and first consultation with provider, defined as > 1 month), diagnosis (between first consultation and receiving a diagnosis, defined as > 3 months), and treatment (between diagnosis and starting treatment, defined as > 3 months). Results Among 214 patients with cancer who completed the survey, median age at diagnosis was 46 years, and the most common cancer was cancer of the cervix (42.2%). Eighty-one percent of patients were women, 60.7% were HIV infected, and 56.6% presented with advanced cancer (stage III or IV). Twenty-six percent of patients experienced delays in appraisal, 35.5% experienced delays help seeking, 63.1% experienced delays in diagnosis, and 50.4% experienced delays in treatment. Patient income, education, and age were not associated with delays. In univariable analysis, patients living with larger families were less likely to experience a help-seeking delay (odds ratio [OR], 0.31; P = .03), women and patients with perceived very serious symptoms were less likely to experience an appraisal delay (OR, 0.45; P = .032 and OR, 0.14; P = .02, respectively). Conclusion Nearly all patients surveyed experienced a delay in obtaining cancer care. In a setting where care is provided without charge, cancer type and male sex were more important predictors of delays than socioeconomic factors.

Efficacy of 18-fluoro deoxy glucose-positron emission tomography computed tomography for the detection of colonic neoplasia proximal to obstructing colorectal cancer

Identification of secondary colonic neoplasia proximal to obstructing colorectal cancer is essential for determining the range of colorectal resection.We examined the accuracy of 18-fluoro deoxy glucose-positron emission tomography (FDG-PET) for detection of colonic neoplasia.We recruited patients with obstructing colorectal cancer from our registry. Preoperative FDG-PET was performed, and the detection rate for colonic neoplasia was estimated. Preoperative colonoscopy or postoperative colonoscopy within a year after operation was employed as the indexed standard.Ninety-three patients were included in this study. Colonic neoplasia proximal to obstruction was confirmed in 83 cases. The sensitivity and positive predictive value of FDG-PET were 25.3% and 77.8%, respectively. The sensitivity was higher in larger lesions (3.2% for <5 mm, 29.4% for 6-10 mm, 45.5% for 11-20 mm, and 71.4% for >21 mm) and in higher pathological grade lesions (14.6% for low-grade adenoma, 38.5% for high-grade adenoma, 66.7% for carcinoma in situ, and 100% for invasive carcinoma). The round shape in PET images was a predictor for neoplasia, with an area under the curve of 0.75293 at an aspect ratio of 1.70.FDG-PET should be used as a screening modality for invasive colorectal cancer (CRC) proximal to obstructing colorectal cancer.

The Association Between Provider Price and Complication Rates for Outpatient Surgical Services

BACKGROUND

Wide variations exist in price and quality for health-care services, but the link between price and quality remains uncertain.

OBJECTIVE

This paper used claims data from a large commercially insured population to assess the association between both procedure- and provider-level prices and complication rates for three common outpatient surgical services.

DESIGN

This is a retrospective cohort study.

SETTING

The study used medical claims data from commercial health plans between 2009 and 2013 for three outpatient surgical services-joint arthroscopy, cataract surgery, and colonoscopy.

MAIN MEASURES

For each procedure, price was assessed as the sum of patient, employer, and insurer spending. Complications were identified using existing algorithms specific to each service. Multivariate regressions were used to risk-adjust prices and complication rates. Provider-level price and complication rates were compared by calculating standardized differences that compared provider risk-adjusted price and complication rates with other providers within the same geographic market. The association between provider-level risk-adjusted price and complication rates was estimated using a linear regression.

KEY RESULTS

Across the three services, there was an inverse association between both procedure- and provider-level prices and complication rates. For joint arthroscopy, cataract surgery, and colonoscopy, a one standard deviation increase in procedure-level price was associated with 1.06 (95% CI 1.05-1.08), 1.14 (95% CI 1.11-1.16), and 1.07 (95% CI 1.06-1.07) odds increases in the rate of procedural complications, respectively. A one standard deviation increase in risk-adjusted provider price was associated with 0.09 (95% CI 0.07 to 0.11), 0.02 (95% CI 0.003 to 0.05), and 0.32 (95% CI 0.29 to 0.34) standard deviation increases in the rate of provider risk-adjusted complication rates, respectively.

LIMITATIONS

Results may be due to unobserved factors. Only three surgical services were examined, and the results may not generalize to other services and procedures. Quality measurements did not include patient satisfaction or experience measures.

CONCLUSIONS

For three common outpatient surgical services, procedure- and provider-level prices are associated with modest increased rates of complication rates.

Adherence to colorectal cancer screening measured as the proportion of time covered

BACKGROUND AND AIMS

Colorectal cancer (CRC) screening can reduce CRC incidence and mortality, but measuring screening adherence over time is challenging. We examined adherence using a novel measure characterizing the proportion of time covered (PTC) by screening tests.

METHODS

Eligible patients were age 50 to 60 years and followed at a large, safety-net health care system between January 2010 and September 2014. We estimated PTC as the number of days up to date with screening divided by the number of days from cohort entry until study end, CRC diagnosis, or death. We estimated mean and median PTC and used least-significant difference tests to assess differences in adherence by patient characteristics.

RESULTS

Of 18,257 patients, most were non-Hispanic black (40.5%) or Hispanic (34.9%) and/or female (62.4%). Approximately 40% (n = 7559) were never screened during the study period; the remaining 10,698 patients completed 19,105 screening examinations (14,481 fecal immunochemical tests [FITs], 4393 colonoscopies, 94 sigmoidoscopies, and 137 barium enemas). Overall, the mean PTC was 29.1% (95% confidence interval [CI], 28.6%-29.5%). Among those who completed at least one screening test (n = 10,698), the mean PTC was 49.0% (95% CI, 48.5%-49.5%). The most common reasons for non-adherence were lack of repeat FIT and no diagnostic colonoscopy after abnormal results for the FIT. The mean PTC increased with the number of primary care visits (0 visits, 21%; 1 visit, 29%; 2-3 visits, 35%; ≥4 visits, 37%; all P < .05).

CONCLUSIONS

PTC provides a reliable estimate of screening adherence, capturing breakdowns in the CRC screening process amenable to intervention. Repeat FIT and diagnostic colonoscopy are important intervention targets that may increase adherence in underserved populations.

Comparison of Microbiota in Patients Treated by Surgery or Chemotherapy by 16S rRNA Sequencing Reveals Potential Biomarkers for Colorectal Cancer Therapy

Colorectal cancer (CRC) is the third most diagnosed cancer worldwide due to its high difficulty in early diagnosis, high mortality rate and short life span. Recent publications have demonstrated the involvement of the commensal gut microbiota in the initiation, progression and chemoresistance of CRC. However, this microbial community has not been explored within CRC patients after anti-cancer treatments. To this end, we performed next generation sequencing-based metagenomic analysis to determine the composition of the microbiota in CRC patients after anti-cancer treatments. The microbial 16S rRNA genes were analyzed from a total of 69 fecal samples from four clinical groups, including healthy individuals, CRC patients, and CRC patients treated with surgery or chemotherapy. The findings suggested that surgery greatly reduced the bacterial diversity of the microbiota in CRC patients. Moreover, Fusobacterium nucleatum were shown to confer chemoresistance during CRC therapy, and certain bacterial strains or genera, such as the genus Sutterella and species Veillonella dispar, were specifically associated with CRC patients who were treated with chemotherapeutic cocktails, suggesting their potential relationships with chemoresistance. These candidate bacterial genera or strains may have the ability to enhance the dosage response to conventional chemotherapeutic cocktails or reduce the side effects of these cocktails. A combination of common CRC risk factors, such as age, gender and BMI, identified in this study improved our understanding of the microbial community and its compositional variation during anti-cancer treatments. However, the underlying mechanisms of these microbial candidates remain to be investigated in animal models. Taken together, the findings of this study indicate that fecal microbiome-based approaches may provide additional methods for monitoring and optimizing anti-cancer treatments.

Optimizing colorectal cancer screening by race and sex: Microsimulation analysis II to inform the American Cancer Society colorectal cancer screening guideline

BACKGROUND

Colorectal cancer (CRC) risk varies by race and sex. This study, 1 of 2 microsimulation analyses to inform the 2018 American Cancer Society CRC screening guideline, explored the influence of race and sex on optimal CRC screening strategies.

METHODS

Two Cancer Intervention and Surveillance Modeling Network microsimulation models, informed by US incidence data, were used to evaluate a variety of screening methods, ages to start and stop, and intervals for 4 demographic subgroups (black and white males and females) under 2 scenarios for the projected lifetime CRC risk for 40-year-olds: 1) assuming that risk had remained stable since the early screening era and 2) assuming that risk had increased proportionally to observed incidence trends under the age of 40 years. Model-based screening recommendations were based on the predicted level of benefit (life-years gained) and burden (required number of colonoscopies), the incremental burden-to-benefit ratio, and the relative efficiency in comparison with strategies with similar burdens.

RESULTS

When lifetime CRC risk was assumed to be stable over time, the models differed in the recommended age to start screening for whites (45 vs 50 years) but consistently recommended screening from the age of 45 years for blacks. When CRC risk was assumed to be increased, the models recommended starting at the age of 45 years, regardless of race and sex. Strategies recommended under both scenarios included colonoscopy every 10 or 15 years, annual fecal immunochemical testing, and computed tomographic colonography every 5 years through the age of 75 years.

CONCLUSIONS

Microsimulation modeling suggests that CRC screening should be considered from the age of 45 years for blacks and for whites if the lifetime risk has increased proportionally to the incidence for younger adults. Cancer 2018;124:2974-85. © 2018 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

Colon cancer screening with CT colonography: logistics, cost-effectiveness, efficiency and progress

Colorectal cancer (CRC) incidence and mortality can be significantly reduced by population screening. Several different screening methods are currently in use, and this review focuses specifically on the imaging technique computed tomographic colonography (CTC). The challenges and logistics of CTC screening, as well as the importance of test accuracy, uptake, quality assurance and cost-effectiveness will be discussed. With comparable advanced adenoma detection rates to colonoscopy (the most commonly used whole-colon investigation), CTC is a less-invasive alternative, requiring less laxative, and with the potential benefit that it permits assessment of extra colonic structures. Three large-scale European trials have contributed valuable evidence supporting the use of CTC in population screening, and highlight the importance of selecting appropriate clinical management pathways based on initial CTC findings. Future research into CTC-screening will likely focus on radiologist training and CTC quality assurance, with identification of evidence-based key performance indicators that are associated with clinically-relevant outcomes such as the incidence of post-test interval cancers (CRC occurring after a presumed negative CTC). In comparison to other CRC screening techniques, CTC offers a safe and accurate option that is particularly useful when colonoscopy is contraindicated. Forthcoming cost-effectiveness analyses which evaluate referral thresholds, the impact of extra-colonic findings and real-world uptake will provide useful information regarding the feasibility of future CTC population screening.

Colorectal Cancer: How Familiar Are Our Future Doctors with the Cancer of Tomorrow?

Background

Colorectal cancer (CRC) is one of the common cancers affecting both genders. Although the incidence of CRC is low in India there has been an increase in the past few decades.

Objective

To assess the awareness regarding colorectal cancer and its screening among medical students and interns.

Methods

This cross-sectional study was conducted among 290 participants (final year medical students and interns) from Kasturba Medical College, Mangalore. A pretested semistructured questionnaire was used to collect information. Data was analyzed using SPSS 17.0.

Results

Majority of participants had satisfactory knowledge regarding CRC. 38% of them scored excellently, 64.8% had good knowledge, and 5.2% scored poorly. Knowledge regarding CRC symptoms was good (95%). 92% of the participants were aware of risk factors of CRC. Only 49% of the participants identified FOBT as a screening tool and 30.7% participants knew that 50 years is the recommended age to begin CRC screening. Interns and international students had better knowledge than final year medical students and Indian students and this was found to be statistically significant.

Conclusion

There is a need to improve participant's knowledge regarding CRC screening although majority of them are aware of CRC symptoms and risk factors.

Colorectal cancer screening for average-risk adults: 2018 guideline update from the American Cancer Society

In the United States, colorectal cancer (CRC) is the fourth most common cancer diagnosed among adults and the second leading cause of death from cancer. For this guideline update, the American Cancer Society (ACS) used an existing systematic evidence review of the CRC screening literature and microsimulation modeling analyses, including a new evaluation of the age to begin screening by race and sex and additional modeling that incorporates changes in US CRC incidence. Screening with any one of multiple options is associated with a significant reduction in CRC incidence through the detection and removal of adenomatous polyps and other precancerous lesions and with a reduction in mortality through incidence reduction and early detection of CRC. Results from modeling analyses identified efficient and model-recommendable strategies that started screening at age 45 years. The ACS Guideline Development Group applied the Grades of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria in developing and rating the recommendations. The ACS recommends that adults aged 45 years and older with an average risk of CRC undergo regular screening with either a high-sensitivity stool-based test or a structural (visual) examination, depending on patient preference and test availability. As a part of the screening process, all positive results on noncolonoscopy screening tests should be followed up with timely colonoscopy. The recommendation to begin screening at age 45 years is a qualified recommendation. The recommendation for regular screening in adults aged 50 years and older is a strong recommendation. The ACS recommends (qualified recommendations) that: 1) average-risk adults in good health with a life expectancy of more than 10 years continue CRC screening through the age of 75 years; 2) clinicians individualize CRC screening decisions for individuals aged 76 through 85 years based on patient preferences, life expectancy, health status, and prior screening history; and 3) clinicians discourage individuals older than 85 years from continuing CRC screening. The options for CRC screening are: fecal immunochemical test annually; high-sensitivity, guaiac-based fecal occult blood test annually; multitarget stool DNA test every 3 years; colonoscopy every 10 years; computed tomography colonography every 5 years; and flexible sigmoidoscopy every 5 years. CA Cancer J Clin 2018;68:250-281. © 2018 American Cancer Society.

Cancer screening in the United States, 2018: A review of current American Cancer Society guidelines and current issues in cancer screening

Each year, the American Cancer Society publishes a summary of its guidelines for early cancer detection, data and trends in cancer screening rates from the National Health Interview Survey, and select issues related to cancer screening. In this 2018 update, we also summarize the new American Cancer Society colorectal cancer screening guideline and include a clarification in the language of the 2013 lung cancer screening guideline. CA Cancer J Clin 2018;68:297-316. © 2018 American Cancer Society.

Mediterranean dietary components are inversely associated with advanced colorectal polyps: A case-control study

AIM

To evaluate the association between the Mediterranean diet (MD) pattern and its components, and advanced colorectal polyps (adenoma and serrated adenoma).

METHODS

A case-control study among patients undergoing screening, diagnostic or surveillance colonoscopies during 2010-2015 at the Tel-Aviv Medical Center, Gastroenterology Department. Cases with advanced polyps were defined as: Advanced adenoma [> 10 mm, with features of high grade dysplasia (HGD) or villous histology], advanced serrated adenoma (> 10 mm or with dysplasia) or multiple (≥ 3) non-advanced adenomas or serrated adenomas. Cases of non-advanced adenomas were defined as adenomas < 10 mm, without features of HGD or villous histology. Controls were defined as those without polyps at the current colonoscopy and without a history of colorectal polyps. Data collection included: anthropometrics measured according to a standardized protocol, fasting blood tests performed at the same lab, medical history recorded by a structured interview and dietary intake evaluated by a 116-item food frequency questionnaire. Adherence to the MD components was evaluated according to intake above/below the sample median, for potentially beneficial/detrimental components respectively, as accepted.

RESULTS

We recruited 206 cases with advanced polyps, 192 cases with non-advanced adenoma and 385 controls. The number of adhered MD components was inversely associated with a diagnosis of advanced polyps in a dose-response manner (OR = 0.34, 95%CI: 0.17-0.65; OR = 0.22, 95%CI: 0.11-0.43; and OR = 0.18, 95%CI: 0.07-0.47 for 3-4, 5-7 and 8-10 components, respectively), but not with non-advanced adenomas (OR = 0.54, 95%CI: 0.25-1.13; OR = 0.48, 95%CI: 0.23-0.99; and OR = 0.43, 95%CI: 0.16-1.12 for 3-4, 5-7 and 8-10 components, respectively). Low intake of sugar-sweetened beverages and red meat, as well as high intake of fish, were inversely associated with advanced polyps (OR = 0.56, 95%CI: 0.36-0.87; OR = 0.63, 95%CI: 0.42-0.95; and OR = 0.66, 95%CI: 0.44-0.99, respectively), while only low intake of red meat was inversely associated with non-advanced adenomas (OR = 0.71, 95%CI: 0.49-0.97).

CONCLUSION

A better adherence to the MD, specifically low intake of sugar-sweetened beverages and red meat as well as high intake of fish, is related to lower odds for advanced polyps.

Disparities in survival for right-sided vs. left-sided colon cancers in young patients: a study based on the Surveillance, Epidemiology, and End Results database (1990-2014)

Purpose

To investigate whether young patients exhibit different characteristics and survival according to tumor location and stage using data from the Surveillance, Epidemiology, and End Results (SEER) database.

Patients and methods

Young patients (20–49 years old) with stage I–III colon cancers were identified from the SEER program from 1990 to 2014. Kaplan–Meier survival analysis and Cox proportional hazards regression were used to analyze the data. Subset analyses were also done among different age and stage subgroups.

Results

Of 8197 patients, 3709 (45.2%) had right-sided colon cancers (RCCs). Patients with RCCs were more likely to be male, to be younger, and to have more poorly differentiated and more advanced tumors. The Kaplan–Meier survival curves and univariate survival models revealed that left-sided colon cancers (LCCs) had lower mortality for all stages combined and stage III, but higher mortality for stage II, compared with right-sided tumors. However, multivariate Cox regression models showed no significant survival differences by location for all patients (adjusted hazard ratio [HR], 0.95; 95% confidence interval [CI], 0.86–1.05; P=0.34) or for stage I (adjusted HR, 1.47; 95% CI, 0.82–2.63; P=0.20). Stage II left-sided cancers had higher mortality (adjusted HR, 1.24; 95% CI, 1.00–1.54; P=0.048), whereas stage III left-sided cancers had lower mortality (adjusted HR, 0.86; 95% CI, 0.77–0.97; P=0.01). For 20- to 39-year-old patients, a significant difference was only found in stage II disease, with a higher mortality for left-sided tumors (adjusted HR, 1.82; 95% CI, 1.12–2.97; P=0.02). However, for 40- to 49-year-old patients, a significant difference was only found in stage III disease, with a lower mortality for left-sided tumors (adjusted HR, 0.83; 95% CI, 0.72–0.95; P=0.008).

Conclusion

In patients younger than 50 years, there were no significant differences in mortality between RCCs and LCCs for all stages combined after adjusting for multiple clinicopathological features. However, RCCs had lower mortality in stage II (especially in 20- to 39-year-old patients) and higher mortality in stage III (especially in 40- to 49-year-old patients).

P2Y2 Receptor Functions in Cancer: A Perspective in the Context of Colorectal Cancer

Purinergic signaling has recently emerged as a network of signaling molecules, enzymes and receptors that coordinates the action and behavior of cancerous cells. Extracellular adenosine 5' triphosphate activates a plethora of P2 nucleotide receptors that can putatively modulate cancer cell proliferation, survival and dissemination. In this context, the G protein-coupled P2Y₂ receptor was identified as one of the entities coordinating the cellular and molecular events that characterize cancerous cells. In this chapter, we will look at the contribution of the P2Y₂ receptor in cancer outcomes and use this information to demonstrate that the P2Y₂ receptor represents a drug target of interest in the setting of colorectal cancer, for which the role and function of this receptor is poorly defined. More particularly, we will review how the P2Y₂ receptor modulates cancer cell proliferation and survival, while promoting cell dissemination and formation of metastases. Finally, we will investigate how the P2Y₂ receptor can contribute to the detrimental development of drug resistance that is often observed in cancerous cells.

Understanding Cancer Worry Among Patients in a Community Clinic-Based Colorectal Cancer Screening Intervention Study

BACKGROUND

To reduce colorectal cancer (CRC) screening disparities, it is important to understand correlates of different types of cancer worry among ethnically diverse individuals.

OBJECTIVES

The current study examined the prevalence of three types of cancer worry (i.e., general cancer worry, CRC-specific worry, and worry about CRC test results) as well as sociodemographic and health-related predictors for each type of cancer worry.

METHODS

Participants were aged 50-75, at average CRC risk, nonadherent to CRC screening guidelines, and enrolled in a randomized controlled trial to increase CRC screening. Participants completed a baseline questionnaire assessing sociodemographics, health beliefs, healthcare experiences, and three cancer worry measures. Associations between study variables were examined with separate univariate and multivariable logistic regression models.

RESULTS

Responses from a total of 416 participants were used. Of these, 47% reported experiencing moderate-to-high levels of general cancer worry. Predictors of general cancer worry were salience and coherence (aOR = 1.1, 95% CI [1.0, 1.3]), perceived susceptibility (aOR = 1.2, 95% CI [1.1, 1.3), and social influence (aOR = 1.1, 95% CI [1.0, 0.1]). Fewer (23%) reported moderate-to-high levels of CRC-specific worry or CRC test worry (35%). Predictors of CRC worry were perceived susceptibility (aOR = 1.4, 95% CI [1.3, 1.6]) and social influence (aOR = 1.1, 95% CI [1.0, 1.2]); predictors of CRC test result worry were perceived susceptibility (aOR = 1.2, 95% CI [1.1, 1.3) and marital status (aOR = 2.0, 95% CI [1.1, 3.7] for married/partnered vs. single and aOR = 2.3, 95% CI [1.3, 4.1] for divorced/widowed vs. single).

DISCUSSION

Perceived susceptibility consistently predicted the three types of cancer worry, whereas other predictors varied between cancer worry types and in magnitude of association. The three types of cancer worry were generally predicted by health beliefs, suggesting potential malleability. Future research should include multiple measures of cancer worry and clear definitions of how cancer worry is measured.

The expression of telomere-related proteins and DNA damage response and their association with telomere length in colorectal cancer in Saudi patients

Background

Colorectal cancer is the leading cause of cancer-related deaths in Saudi Arabia. Cancer has a multifactorial nature and can be described as a disease of altered gene expression. The profiling of gene expression has been used to identify cancer subtypes and to predict patients’ responsiveness. Telomere-associated proteins that regulate telomere biology are essential molecules in cancer development. Thus, the present study examined their contributions to colorectal cancer progression in Saudi patients.

Methods

The expression of hTERT, TRF1, TRF2, POT1, ATR, ATM, Chk1 and Chk2 were measured via real-time PCR in matched cancerous and adjacent tissues of CRC patients. The protein level of hTERT, TRF1, TRF2, ATR, ATM, Chk1 and Chk2 were measured using immunohistochemistry. A region of hTERT core promoter was sequenced via Sanger sequencing. Methylation of CTCF binding site was examined via methylation-specific PCR. Finally, the length of telomere was estimated using q-PCR.

Results

Our results showed that POT1, ATR, Chk1 and Chk2 show increased expression in CRC relative to the adjacent mucosa. The expression levels of each gene were associated with clinicopathological characteristics of patients with CRC. There was a positive correlation between the age of the patients and hTERT expression. Regarding tumor site, telomere length, ATR, ATM and Chk1 were shown to be altered. No somatic mutation was detected in hTERT core promoter, and no differences in methylation patterns at CTCF binding site in the promoter between normal and cancer tissues.

Conclusion

Analysis of targeted genes expression in colorectal cancer based on the clinical variables revealed that tumor location and age could have a role in gene expression and telomere length variations and this could be taken under consideration during CRC diagnosis and therapy. Other epigenetic mechanisms could influence hTERT expression in cancers. Our findings warrant further validation through experiments involving a larger number of patients.

Family history of colorectal cancer in first-degree relatives and metachronous colorectal adenoma

OBJECTIVES

Little is known about the relationship between having a first-degree relative (FDR) with colorectal cancer (CRC) and risk for metachronous colorectal adenoma (CRA) following polypectomy.

METHODS

We pooled data from seven prospective studies of 7697 patients with previously resected CRAs to quantify the relationship between having a FDR with CRC and risk for metachronous adenoma.

RESULTS

Compared with having no family history of CRC, a positive family history in any FDR was significantly associated with increased odds of developing any metachronous CRA (OR = 1.14; 95% CI = 1.01-1.29). Higher odds of CRA were observed among individuals with an affected mother (OR = 1.27; 95% CI = 1.05-1.53) or sibling (OR = 1.34; 95% CI = 1.11-1.62) as compared with those without, whereas no association was shown for individuals with an affected father. Odds of having a metachronous CRA increased with number of affected FDRs, with ORs (95% CIs) of 1.07 (0.93-1.23) for one relative and 1.39 (1.02-1.91) for two or more. Younger age of diagnosis of a sibling was associated with higher odds of metachronous CRA, with ORs (95% CIs) of 1.66 (1.08-2.56) for diagnosis at <54 years; 1.34 (0.89-2.03) for 55-64 years; and 1.10 (0.70-1.72) for >65 years (p-trend = 0.008). Although limited by sample size, results for advanced metachronous CRA were similar to those for any metachronous CRA.

CONCLUSIONS

A family history of CRC is related to a modestly increased odds of metachronous CRA. Future research should explore whether having a FDR with CRC, particularly at a young age, should have a role in risk stratification for surveillance colonoscopy.

A Cross-Sectional Assessment of Literacy and Awareness, Attitudes, and Beliefs About Colorectal Cancer and Its Screening in Riyadh Region

This study aims to explore the association between functional health literacy and awareness for, beliefs, and attitudes of patients with colorectal cancer (CRC) and CRC screening test in Riyadh, Saudi Arabia. A total of 256 participants from two different tertiary level hospitals in Riyadh, Saudi Arabia were recruited in this study. The participants were interviewed by a trained researcher between October and December 2015. All respondents answered a three-part questionnaire which included demographic data, questions related to CRC awareness, attitude, behaviour, and short Test of Functional Health Literacy in Adults (STOFHLA). More than half of the participants had an inadequate awareness of functional health literacy skills (FHLS), 16.4 % had marginal of FHLS awareness and 17.6 % had adequate awareness about FHLS as assessed by the STOFHLA. Overall, the majority of the participants in both marginal and adequate aware groups showed a limited awareness about colorectal cancer screening and testing. A significant association was found on awareness of the patients about frequencies that they should have been tested for colorectal cancer and functional health literacy. No significant association was found between functional health literacy as assessed by STOFHLA and concerns of Faecal Occult Blood Test (FOBT) (p = 0.384) and sigmoidoscopy or colonoscopy might cause embarrassment (p = 0.089), harm (p = 0.917), and pain (p = 0.849). The present study revealed a low level of health literacy among Saudi adults in Riyadh region. Although the level of literacy was low, the bigger concern is that of the poor awareness and beliefs of Saudi adults about CRC and CRC screening.

Dietary patterns and risk of advanced colorectal neoplasms: A large population based screening study in Germany

Specific components of the diet such as red and processed meat have been associated with the risk of developing colorectal cancer. However, evidence on the association of dietary patterns with colorectal neoplasms is sparse. The aim of this study was to analyze the association of dietary patterns with prevalence of advanced colorectal neoplasms among older adults in Germany. A cross-sectional study was conducted among participants of screening colonoscopy in Saarland, Germany, who were enrolled in the KolosSal study (Effektivität der Früherkennungs-Koloskopie: eine Saarland-weite Studie) from 2005 to 2013. Information on diet and lifestyle factors was obtained through questionnaires and colonoscopy results were extracted from physicians' reports. Associations of a priori defined dietary patterns (vegetarian or adapted versions of the Healthy Eating Index [HEI] and the Dietary Approaches to Stop Hypertension [DASH] index) with the risk of advanced colorectal neoplasms were assessed by multiple logistic regression analyses with comprehensive adjustment for potential confounders. A total of 14,309 participants were included (1561 with advanced colorectal neoplasms). Healthier eating behavior was associated with lower prevalence of advanced colorectal neoplasms in a dose-response manner. Adjusted odds ratios (95% confidence intervals) comparing the highest with the lowest categories of adapted HEI and DASH were 0.61 (0.50, 0.76) and 0.70 (0.55, 0.89), respectively. No significant associations were observed for a vegetarian eating pattern (adjusted OR 0.80 (0.55, 1.17)). Healthy dietary patterns, as described by a high HEI or DASH score, but not a vegetarian diet alone, are associated with reduced risk of advanced colorectal neoplasms.

The impact of the rising colorectal cancer incidence in young adults on the optimal age to start screening: Microsimulation analysis I to inform the American Cancer Society colorectal cancer screening guideline

BACKGROUND

In 2016, the Microsimulation Screening Analysis‐Colon (MISCAN‐Colon) model was used to inform the US Preventive Services Task Force colorectal cancer (CRC) screening guidelines. In this study, 1 of 2 microsimulation analyses to inform the update of the American Cancer Society CRC screening guideline, the authors re‐evaluated the optimal screening strategies in light of the increase in CRC diagnosed in young adults.

METHODS

The authors adjusted the MISCAN‐Colon model to reflect the higher CRC incidence in young adults, who were assumed to carry forward escalated disease risk as they age. Life‐years gained (LYG; benefit), the number of colonoscopies (COL; burden) and the ratios of incremental burden to benefit (efficiency ratio [ER] = ΔCOL/ΔLYG) were projected for different screening strategies. Strategies differed with respect to test modality, ages to start (40 years, 45 years, and 50 years) and ages to stop (75 years, 80 years, and 85 years) screening, and screening intervals (depending on screening modality). The authors then determined the model‐recommended strategies in a similar way as was done for the US Preventive Services Task Force, using ER thresholds in accordance with the previously accepted ER of 39.

RESULTS

Because of the higher CRC incidence, model‐predicted LYG from screening increased compared with the previous analyses. Consequently, the balance of burden to benefit of screening improved and now 10‐yearly colonoscopy screening starting at age 45 years resulted in an ER of 32. Other recommended strategies included fecal immunochemical testing annually, flexible sigmoidoscopy screening every 5 years, and computed tomographic colonography every 5 years.

CONCLUSIONS

This decision‐analysis suggests that in light of the increase in CRC incidence among young adults, screening may be offered earlier than has previously been recommended. Cancer 2018;124:2964‐73. © 2018 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

Colorectal cancer incidence has been increasing since the mid‐1990s in adults aged <50 years. A well‐established decision‐analytic modeling approach suggests that in light of this increasing incidence, the optimal age to start colorectal cancer screening is 45 years.

See also pages 2974‐85.

CT colonography: size reduction of submerged colorectal polyps due to electronic cleansing and CT-window settings

OBJECTIVES

To assess whether electronic cleansing (EC) of tagged residue and different computed tomography (CT) windows influence the size of colorectal polyps in CT colonography (CTC).

METHODS

A database of 894 colonoscopy-validated CTC datasets of a low-prevalence cohort was retrospectively reviewed to identify patients with polyps ≥6 mm that were entirely submerged in tagged residue. Ten radiologists independently measured the largest diameter of each polyp, two-dimensionally, before and after EC in colon, bone, and soft-tissue-windows, in randomised order. Differences in size and polyp count before and after EC were calculated for size categories ≥6 mm and ≥10 mm. Statistical testing involved 95% confidence interval, intraclass correlation and mixed-model ANOVA.

RESULTS

Thirty-seven patients with 48 polyps were included. Mean polyp size before EC was 9.8 mm in colon, 9.9 mm in bone and 8.2 mm in soft-tissue windows. After EC, the mean polyp size decreased significantly to 9.4 mm in colon, 9.1 mm in bone and 7.1 mm in soft-tissue windows. Compared to unsubtracted colon windows, EC, performed in colon, bone and soft-tissue windows, led to a shift of 6 (12,5%), 10 (20.8%) and 25 (52.1%) polyps ≥6 mm into the next smaller size category, thus affecting patient risk stratification.

CONCLUSIONS

EC and narrow CT windows significantly reduce the size of polyps submerged in tagged residue. Polyp measurements should be performed in unsubtracted colon windows.

KEY POINTS

• EC significantly reduces the size of polyps submerged in tagged residue. • Abdominal CT-window settings significantly underestimate 2D sizes of submerged polyps. • Size reduction in EC is significantly greater in narrow than wide windows. • Underestimation of polyp size due to EC may lead to inadequate treatment. • Polyp measurements should be performed in unsubtracted images using a colon window.

Flexible sigmoidoscopy in colorectal cancer screening: implications of different colonoscopy referral strategies

Flexible sigmoidoscopy (FS) screening reduces colorectal cancer incidence and mortality. Its potential to detect proximal neoplasms depends on colonoscopy referral. We estimated diagnostic performance of sigmoidoscopy using 12 different referral criteria in detecting colorectal cancer and advanced adenomas. Colonoscopy results from 14,947 participants of screening colonoscopy in Germany were used to derive sensitivity of sigmoidoscopy for colorectal cancer, advanced adenomas (AAs), and any advanced neoplasms in the proximal colon. It was assumed that FS detects the same neoplasms as colonoscopy within its reach and that distal neoplasms would be followed by colonoscopy. In addition, numbers of colonoscopies needed (NCN) to detect one proximal advanced neoplasm were calculated. The most advanced findings during colonoscopy were colorectal cancer in 213 subjects (1.4%), AA in 1539 subjects (10.2%) and non-advanced adenomas in 2988 subjects (19.8%). Without colonoscopy referral, overall sensitivities for any colorectal cancer, advanced adenoma and any advanced neoplasm (proximal or distal) would be 79, 65 and 66%, respectively. These sensitivities could be increased to up to 86, 83 and 84% by the referral strategies investigated. Compared to referral due to advanced adenomas, referral due to non-advanced adenomas would substantially increase the NCN at a modest gain in sensitivity. Sensitivities were higher and NCNs were lower in men than in women for every strategy. In conclusion, colonoscopy referral can substantially increase sensitivity of sigmoidoscopy-based screening, but the gain by referral due to non-advanced adenomas substantially increases NCN compared to referral due to advanced neoplasms only. Major sex differences may call for sex-specific referral strategies.

Emotional predictors of bowel screening: the avoidance-promoting role of fear, embarrassment, and disgust

Background

Despite considerable efforts to address practical barriers, colorectal cancer screening numbers are often low. People do not always act rationally, and investigating emotions may offer insight into the avoidance of screening. The current work assessed whether fear, embarrassment, and disgust predicted colorectal cancer screening avoidance.

Methods

A community sample (N = 306) aged 45+ completed a questionnaire assessing colorectal cancer screening history and the extent that perceptions of cancer risk, colorectal cancer knowledge, doctor discussions, and a specifically developed scale, the Emotional Barriers to Bowel Screening (EBBS), were associated with previous screening behaviours and anticipated bowel health decision-making.

Results

Step-wise logistic regression models revealed that a decision to delay seeking healthcare in the hypothetical presence of bowel symptoms was less likely in people who had discussed risk with their doctor, whereas greater colorectal cancer knowledge and greater fear of a negative outcome predicted greater likelihood of delay. Having previously provided a faecal sample was predicted by discussions about risk with a doctor, older age, and greater embarrassment, whereas perceptions of lower risk predicted a lower likelihood. Likewise, greater insertion disgust predicted a lower likelihood of having had an invasive bowel screening test in the previous 5 years.

Conclusions

Alongside medical and demographic factors, fear, embarrassment and disgust are worthy of consideration in colorectal cancer screening. Understanding how specific emotions impact screening decisions and behaviour is an important direction for future work and has potential to inform screening development and communications in bowel health.