CRC Risk Factors Research Articles

Developing a Novel Non-invasive Serum-based Diagnostic Test for Early Detection of Colorectal Cancer

Abstract Introduction/Objective Colorectal cancer (CRC) is the third-most common cancer worldwide, and early detection is vital for successful treatment and improved outcomes. Current screening methods such as colonoscopy, fecal occult blood tests, and stool DNA tests have limitations such as patient discomfort, cost, and low sensitivity and specificity most commonly diagnosed cancer worldwide with a high mortality rate. Early detection remains a crucial factor in reducing the burden of CRC. Currently, the gold standard for CRC diagnosis is colonoscopy, but it may not be feasible for widespread screening due to its invasiveness, cost, and patient compliance issues. Therefore, there is a great need to identify reliable biomarkers that can detect CRC at an early stage. This study aimed to evaluate the effectiveness of updated novel biomarkers for early detection of CRC. Methods/Case Report This study was conducted on 158 patients with suspected or confirmed CRC. The study population included patients of both genders, aged above 18 years, and with a history of CRC or other relevant risk factors. Blood samples were collected from all included patients, and the biomarkers (CTCS, miRNAs, ctDNA, and Methylated DNA markers ) were measured using enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) tests. Novel biomarkers compared their diagnostic performance with existing biomarkers such as fecal occult blood tests (FOBTs), fecal immunochemical tests (FITs), and CEA. Results (if a Case Study enter NA) The studied biomarkers (CTCs, microRNAs, ctDNA, and Methylated DNA markers) have high sensitivity from 78.8 % to 96.72% and accuracy from 83.76% to 94.83% as well as their cut-off which approved the objective of this study. Overall, these novel biomarkers show promise for early detection of colorectal cancer and may improve screening and early detection efforts. Conclusion The evaluation of the studied biomarkers (Circulating Tumor Cells, microRNAs, Circulating tumor DNA, and Methylated DNA markers) for early detection of CRC has substantial clinical and public health implications. The identification of reliable biomarkers for CRC screening can avoid unnecessary colonoscopies, reduce the burden on healthcare costs, and improve the detection of early-stage CRC.

Recent Advancement of Colorectal Cancer and Their Herbal Essential Oil Treatment

Colorectal cancer is the second most deadly type of cancer (CRC). In the upcoming decades, death and incidence rates would surely increase globally. Despite being disproportionately high in high-income countries, CRC-related mortality is also on the rise in low- and middle-income countries. Early diagnosis of CRC allows for both surgical and medicinal treatment options. Due to the high likelihood of recurrence and the rising rate of treatment failure brought on by cancer medicine resistance, it is regrettable that there is a significant treatment failure rate. Due to early discovery and treatment of CRC, there is a chance of survival in wealthy nations. Contrarily, these resources are noticeably scarce in less developed countries. It is crucial to inform the public about CRC's current situation, its cause, progression, risk factors, and therapy. As a result, we have included in this review all of the most recent data on the global epidemiology, drug resistance, challenges, risk factors, and preventative and therapeutic approaches for CRC. Guidelines for CRC prevention and therapy are briefly reviewed, as well as pathways of CRC developments.

Clinical features of young onset colorectal cancer patients from a large cohort at a single cancer center.

The aim of this study is to describe the demographics and clinical features of patients with young onset (YO) CRC. A retrospective review of patients with CRC diagnosed between ages 20 and 49years was evaluated at the Memorial Sloan Kettering Cancer Center from 1/2004 to 6/2019. We excluded those with a hereditary CRC syndrome, inflammatory bowel disease, or prior CRC diagnosis. Patient demographics; presenting symptoms; medical, surgical, and smoking history; family history of cancer; tumor characteristics; and pathology were obtained from the electronic medical record. We identified 3856 YO CRC patients (median age CRC diagnosis 43; 52.5% male). A total of 59.1% were overweight or obese (32.2% and 26.9%, respectively). Most (90.1%) had no family history of CRC in a first-degree relative; 56.3% of patients reported being never smokers; 5.2% had diabetes. The most common presenting symptoms were rectal bleeding (47.7%), abdominal pain/bloating (33.1%), and change in bowel habits (24.7%). The majority presented with left-sided cancers (77.3%), at late-stage disease (68.4% at stages 3 or 4). Most YO CRC patients presented with rectal bleeding or abdominal pain, left-sided cancers, and later-stage disease and had no family history of CRC in a first-degree relative. Over half were overweight and obese and were more likely to have never smoked. More data are needed to better understand YO CRC risk factors and to help identify high-risk populations who may benefit from earlier screening.

Association of Physical Activity and Sedentary Behavior with Colorectal Cancer Risk in Moroccan Adults: A Large-Scale, Population-Based Case-Control Study.

Background:Physical activity has been associated with a lower risk of colorectal cancer in studies mainly conducted in high-income countries, while sedentary behavior has been suggested to increase CRC risk. In this study, we aimed to investigate the role of physical activity and sedentary behavior on CRC risk in the Moroccan population. Methods:A case-control study was conducted involving 1516 case-control pairs, matched on age, sex and center in five university hospital centers. A structured questionnaire was used to collect information on socio-demographics, lifestyle habits, family history of CRC, and non-steroidal anti-inflammatory drug (NSAID) use. Information on physical activity and sedentary behavior were collected by the Global Physical Activity Questionnaire (GPAQ). For each activity (work, household, and recreational activities), a metabolic equivalent (MET) was calculated using GPAQ recommendations. Conditional logistic regression models were used to assess the association between physical activity, sedentary behavior and the risk of overall CRC, colon cancer, and rectal cancer taking into account other CRC risk factors. Results:High level of physical activity was associated with lower risk of rectal cancer, colon cancer, and overall CRC, the adjusted odds ratios (ORa) for the highest versus the lowest level of activity were 0.67 (95% CI: 0.54-0.82), 0.77 (95% CI: 0.62-0.96), and 0.72 (95% CI: 0.62-0.83), respectively. In contrast, sedentary behavior was positively associated with rectal cancer risk (ORa=1.19, 95% CI: 1.01-1.40), but was unrelated to colon cancer risk (ORa=1.02, 95% CI: 0.87-1.20). Conclusion:We found an inverse association between physical activity and CRC risk in the Moroccan population, and a positive association between sedentary behavior and rectal cancer risk. Considering that one-third of the total population studied had a sedentary lifestyle, these results may be used to improve strategies of public health suitable for Moroccan population.

SIGNIFICANT FACTORS ASSOCIATED WITH INSULIN-LIKE GROWTH FACTOR 1 AND ITS BINDING PROTEIN 3 IN COLORECTAL CANCER – MULTIPLE REGRESSION ANALYSIS

Aim: the aim of our study was to investigate the association of insulin-like growth factor-1 and its binding protein 3 levels with CRC risk factors and symptoms by multiple regression analyzes. Methods: The IGF-1 laboratory test was performed using the ECLIA method. Serum insulin and glucose levels were assessed by oral glucose tolerance test (OGTT) in fasting state and after 120 minutes of glucose loading (40 g / 1 m2 of body surface). Multiple regression analysis performed to study the mutual impact of different parameters on outcome (IGF-1 and IGF BP3). Results: Finally, significant variables (factors) were left in the model having mutual effect on the outcome (IGF BP3 value). The linear multiple regression function took the following form: Hence these factors (each factor in parentheses indicates the nature of the correlation - direct or inverse): X1 - Sex (direct); X4 – Code of Surgery (inverse); X7 – other general pains/symptoms (inverse); X13 - Flatulence Gases (inverse); X14 - Diarrhea (direct); X20 – A course of chemotherapy or radiation therapy before surgery (inverse); X27 – HOMA-S (direct); X28 - HOMA-IR (inverse); X31 – creatinine (direct). Conclusion: Based on the results of current study we concluded that CRC is multifactorial and many significant factors are responsible for its development. One of possible mechanisms for its development is the changes insulin/IGF-1 signaling pathway with other significant biological and non-biological factors.

Screening Colonoscopy Findings Are Associated With Noncolorectal Cancer Mortality.

INTRODUCTION:Controversy exists regarding the impact of various risk factors on noncolorectal cancer (CRC) mortality in healthy screening populations. We examined the impact of known CRC risk factors, including baseline colonoscopy findings, on non-CRC mortality in a screening population.METHODS:Cooperative Studies Program (CSP) #380 is comprised of 3,121 veterans aged 50–75 years who underwent screening colonoscopy from 1994 to 97 and were then followed for at least 10 years or until death. Hazard ratios (HRs) for risk factors on non-CRC mortality were estimated by multivariate Cox proportional hazards.RESULTS:Current smoking (HR 2.12, 95% confidence interval [CI] 1.78–2.52, compared with nonsmokers) and physical activity (HR 0.89, 95% CI 0.84–0.93) were the modifiable factors most associated with non-CRC mortality in CSP#380. In addition, compared with no neoplasia at baseline colonoscopy, non-CRC mortality was higher in participants with ≥3 small adenomas (HR 1.43, 95% CI 1.06–1.94), advanced adenomas (HR 1.32, 95% CI 0.99–1.75), and CRC (HR 2.95, 95% CI 0.98–8.85). Those with 1–2 small adenomas were not at increased risk for non-CRC mortality (HR 1.15, 95% CI 0.94–1.4).DISCUSSION:In a CRC screening population, known modifiable risk factors were significantly associated with 10-year non-CRC mortality. Furthermore, those who died from non-CRC causes within 10 years were more likely to have had high-risk findings at baseline colonoscopy. These results suggest that advanced colonoscopy findings may be a risk marker of poor health outcomes. Integrated efforts are needed to motivate healthy lifestyle changes during CRC screening, particularly in those with high-risk colonoscopy findings and unaddressed risk factors.

Knowledge and awareness of colorectal cancer risk factors, screening, and associated factors in advanced colorectal cancer patients: a multicenter cross-sectional study in China.

BackgroundColorectal cancer (CRC) is the 3rd most common malignancy globally, and its disease burden is increasing rapidly in China. But CRC patients’ knowledge and awareness of CRC have not yet been examined, which could facilitate the identification of targeted population from public for intervention.MethodsA nationwide multicenter cross-sectional survey was conducted in 19 tertiary hospitals (10 cancer hospitals and 9 general hospitals) from March 2020 to March 2021 in China. During study period, all Stage III and IV CRC patients were invited to complete a semi-structured survey that had been designed to collect information about their socio-demographic characteristics, and knowledge and awareness of CRC risk factors and screening. A multivariate logistic regression model was used to identify factors associated with their knowledge and awareness.ResultsIn total, 4,589 advanced CRC patients were enrolled in this study, of whom, 46.2% were from tertiary cancer hospitals, and 59.5% were male. Patients had a mean age of 60.1±11.6 years. Before diagnosis, 65.1% of the patients had no related knowledge of the CRC risk factors, and 84.9% were unaware of the CRC screening-related information. Only 30.4% of patients had actively sought to acquire CRC-related knowledge before diagnosis. The 3 most common knowledge sources were relatives or friends who had been diagnosed with CRC (13.2%), popular science television/broadcast shows (12.9%), and community publicity and education (9.6%). Generally, knowledge and awareness were positively associated with better education level [odds ratios (ORs) ranged from 1.49 to 2.54, P<0.001], annual household income ranged from 50,000 Chinese Yuan (CNY) to 100,000 CNY (OR =1.32, P<0.001), being manual laborer (OR =1.25, P<0.001) and being white-collar worker (OR =1.47, P<0.001).ConclusionsAdvanced CRC patients’ knowledge and awareness of CRC were severely limited before diagnosis. Thus, those who had limited knowledge and awareness should has a priority for intervention.

Geographic determinants of colorectal cancer in Louisiana

PurposeCurrently, rural residents in the United States (US) experience a greater cancer burden for tobacco-related cancers and cancers that can be prevented by screening. We aim to characterize geographic determinants of colorectal cancer (CRC) incidence in Louisiana due to rural residence and other known geographic risk factors, area socioeconomic status (SES), and cultural region (Acadian or French-speaking).MethodsPrimary colorectal cancer diagnosed among adults 30 years and older in 2008–2017 were obtained from the Louisiana Tumor Registry. Population and social and economic data were obtained from US Census American Community Survey. Rural areas were defined using US Department of Agriculture 2010 rural–urban commuting area codes. Estimates of relative risk (RR) were obtained from multilevel binomial regression models of incidence.ResultsThe study population was 16.1% rural, 18.4% low SES, and 17.9% Acadian. Risk of CRC was greater among rural white residents (RR Women: 1.09(1.02–1.16), RR Men: 1.11(1.04–1.18)). Low SES was associated with increased CRC for all demographic groups, with excess risk ranging from 8% in Black men (RR: 1.08(1.01–1.16)) to 16% in white men (RR: 1.16(1.08–1.24)). Increased risk in the Acadian region was greatest for Black men (RR: 1.21(1.10–1.33)) and women (RR: 1.21(1.09–1.33)). Rural–urban disparities in CRC were no longer significant after controlling for SES and Acadian region.ConclusionSES remains a significant determinant of CRC disparities in Louisiana and may contribute to observed rural–urban disparities in the state. While the intersectionality of CRC risk factors is complex, we have confirmed a robust regional disparity for the Acadian region of Louisiana.

Colorectal cancer in the Linxian China Nutrition Intervention Trial: Risk factors and intervention results.

BackgroundColorectal cancer (CRC) is among the most common cancers in economically developed countries and developing world. While dietary factors are associated with risk of CRC in the West and urban China, little is known about risk or protective factors in rural China.MethodsThe Linxian General Population Nutrition Intervention Trial (NIT) cohort was established over 30 years ago to test whether daily multivitamin/mineral supplements could reduce the incidence and mortality of esophageal/gastric cardia cancer. The cohort included a total of 29,553 healthy participants 40–69 years old who were randomly assigned to supplements or placebos via a 24 fractional factorial study design. We examined risk factors for the development of CRC as well as the effects of four different nutritional factors (Factor A: retinol, zinc; B: riboflavin, niacin; C: ascorbic acid, molybdenum; D: selenium, alpha-tocopherol, beta-carotene,) on CRC incidence following 5.25 years of supplementation in this randomized, placebo-controlled intervention trial.ResultsCRC risk increased with age and height as well as piped water usage, family history of CRC, and consumption of foods cooked in oil, eggs, and fresh fruits. No effect on CRC was seen for any of these four intervention factors tested in both genders, but CRC was reduced 37% in females who received Factor D (selenium/alpha-tocopherol/beta-carotene) (RR = 0.63, 95% CI = 0.43–0.92, P = 0.016) compared to females who did not receive Factor D.ConclusionsIn this undernourished rural Chinese population, CRC risk factors in this Chinese cohort showed both similarities and differences compared to Western and urban Asian Chinese populations. Intervention results suggested a potential benefit for women supplemented with selenium/alpha-tocopherol/beta-carotene.

Decreased colorectal cancer incidence and mortality in a diverse urban population with increased colonoscopy screening

BackgroundAlthough colorectal cancer screening has contributed to decreased incidence and mortality, disparities are present by race/ethnicity. The Citywide Colon Cancer Control Coalition (C5) and NYC Department of Health and Mental Hygiene (DOHMH) promoted screening colonoscopy from 2003 on, and hypothesized future reductions in CRC incidence, mortality and racial/ethnic disparities.MethodsWe assessed annual percent change (APC) in NYC CRC incidence, stage and mortality rates through 2016 in a longitudinal cross-sectional study of NY State Cancer Registry, NYC Vital Statistics, and NYC Community Health Survey (CHS) data. Linear regression tested associations between CRC mortality rates and risk factors.ResultsOverall CRC incidence rates from 2000 decreased 2.8% yearly from 54.1 to 37.3/100,000 population in 2016, and mortality rates from 2003 decreased 2.9% yearly from 21.0 to 13.9 in 2016 at similar rates for all racial/ethnic groups. Local stage disease decreased overall with a transient increase from 2002 to 2007. In 2016, CRC incidence was higher among Blacks (42.5 per 100,000) than Whites (38.0), Latinos (31.7) and Asians (30.0). In 2016, Blacks had higher mortality rates (17.9), than Whites (15.2), Latinos (10.4) and Asians (8.8). In 2016, colonoscopy rates among Blacks were 72.2%, Latinos 71.1%, Whites 67.2%, and Asians, 60.9%. CRC mortality rates varied by neighborhood and were independently associated with Black race, CRC risk factors and access to care.ConclusionsIn a diverse urban population, a citywide campaign to increase screening colonoscopy was associated with decreased incidence and mortality among all ethnic/racial groups. Higher CRC burden among the Black population demonstrate more interventions are needed to improve equity.

Development and validation of a risk prediction model for high-risk adenomas at the time of first screening colonoscopy among screening aged Canadians

The aim of this study was to develop a risk prediction model for high risk adenomas (HRAs) detected at screening colonoscopy based on readily available participant information. The cohort consisted of 3035 participants aged 50 to 74 years with no history of cancer who underwent a primary screening colonoscopy at a centralized colon cancer screening centre between 2008 and 2016. A multivariable logistic regression model was created using CRC risk factors identified from prior research. Model covariates were collected from a baseline questionnaire and included participant demographics (age and sex), lifestyle parameters (body mass index, alcohol, smoking, and vitamin D supplement use) and medical history (family history of CRC and diabetes). Mean participant age was 58.8 years, and 54.7% were male. 249 participants with HRAs were identified (8.2%). An adjusted c-statistic of 0.67 was calculated, and a specificity and negative predictive value of 97.2% (95% CI: 96.5–97.8) and 92.5% (95% CI: 92.2–92.8) for the detection of HRAs, respectively, were achieved using 20% predicted probability as a high-risk threshold. However, only a sensitivity of 12.1% (95% CI: 8.3–16.8) was achieved. Our model has moderate predictive ability, with strengths in being able to rule out those with an absence of HRAs on screening colonoscopy. Maximizing screening efficiency through improved risk prediction can enhance resource allocation. Ultimately, this model has the potential to improve patient care by reducing unnecessary colonoscopies, limiting this invasive procedure to those most likely to have significant findings.

Abstract LB-152: Associations between circulating sex hormone levels and risk of colon cancer among men from six European countries

Abstract Colorectal cancer (CRC) is the third most common cancer worldwide and its incidence is rising. Identifying etiologic pathways and early detection for CRC are key to prevention and reducing mortality as the prognosis for advanced CRC, despite recent improvements in therapy, remains poor. One area of potentially measurable CRC risk factors, that is still relatively unexplored, are circulating levels of endogenous sex hormones. The incidence of CRC is greater in men than in women and a proposed hypothesis for this sex disparity is that higher levels of endogenous estrogens found in women may be protective against CRC. In addition, androgens, including testosterone, have been hypothesized to confer protective effects for CRC in men. However, few studies have evaluated the association between testosterone and CRC in men, and the limited available data suggest that any observed protective association is likely confined to colon rather than rectal cancer. The aim of this study was therefore to evaluate the relation of colon cancer risk with circulating levels of sex hormones and sex hormone binding globulin (SHBG) in a male population. Preliminary analyses included data from 461 cases of incident colon cancer and 461 matched controls from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Sex hormones (estradiol, estrone, testosterone, androstenedione, dehydroepiandrosterone, and progesterone) were measured in prediagnostic plasma samples using liquid chromatography-tandem /mass spectrometry (LC/-MS/MS), and SHBG was measured using a solid phase “sandwich” immunoradiometric assay. To test potential associations between circulating levels of sex hormones and SHBG with the risk of developing colon cancer, conditional logistic regression models were applied to estimate odds ratios (OR) and 95% confidence intervals (95% CI). Multivariable models were adjusted for colon cancer risk factors, including anthropometric parameters, alcohol consumption, physical activity and smoking status. In addition, models including estrone, estradiol and testosterone were adjusted for SHBG and vice versa. Preliminary results indicated an inverse association for testosterone (multivariable OR per SD: 0.80 95% CI: 0.69 - 0.93) and SHBG (multivariable OR per SD: 0.84 95% CI: 0.72 - 0.99) with CRC risk. However, after additional adjustments to SHBG and sex hormone models respectively these associations were attenuated towards the null. No associations were identified for estradiol, estrone, androstenedione, dehydroepiandrosterone, and progesterone. These preliminary results do not support an association between endogenous estrogen and colon cancer in men, while a potential association between testosterone and SHBG and colon cancer will need to be further evaluated. Citation Format: Justin Harbs, Sabina Rinaldi, Audrey Gicquiau, Xijia Liu, Marc Gunter, Bethany Van Guelpen, Neil Murphy, Sophia Harlid, Epic Network. Associations between circulating sex hormone levels and risk of colon cancer among men from six European countries [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-152.

A prospective study of erythrocyte polyunsaturated fatty acids and risk of colorectal serrated polyps and conventional adenomas.

The influence of polyunsaturated fatty acids (PUFAs) on risk of colorectal cancer precursors remains largely unknown. We examined the associations of erythrocyte PUFAs, including n-3 and n-6 PUFAs, with risk of colorectal conventional adenomas and serrated polyps in 4517 participants from three US prospective cohorts who had provided a blood sample and undergone at least one endoscopic examination. We calculated the multivariable odds ratios (ORs) per 1 SD increment in individual PUFAs and the ratio of n-6/n-3 PUFAs. We considered P < .005 statistically significant to account for multiple testing. During a median of 20 years of follow-up, we documented 493 conventional adenomas and 316 serrated polyps. After adjusting for various CRC risk factors, no associations for PUFAs achieved the stringent statistical significance for either conventional adenomas or serrated polyps (ORs per 1 SD ranged from 0.90 to 1.14). Some associations achieved nominal significance (P < .05), including the association of dihomogammalinolenic acid (DGLA) (20:3, n-6) with lower risk of conventional adenomas (OR = 0.91; 95% confidence interval [CI] = 0.83-1.00), total n-6 PUFAs with higher risk of proximal serrated polyps (OR = 1.32; 95% CI = 1.01-1.74) and eicosadienoic acid (20:2, n-6) and DGLA with lower risk of advanced adenomas (OR = 0.83; 95% CI = 0.71-0.97 and OR = 0.84; 95% CI = 0.72-0.98, respectively). Our findings indicate that erythrocyte PUFAs in a typical American diet are unlikely to have a substantial influence on risk of colorectal cancer precursors. The subgroup associations require further confirmation.

Low Rate of Cancer Detection by Colonoscopy in Asymptomatic, Average-Risk Subjects with Negative Results From Fecal Immunochemical Tests

Screening colonoscopies are of uncertain benefit for persons with negative results from a fecal immunochemical test (FIT). We investigated detection of CRC by colonoscopy in asymptomatic, average-risk, FIT-negative subjects. We conducted a retrospective, population-based cohort study of 96,804 subjects with an initial negative result from a FIT at ages 50-75 years, from 2008 through 2014, who then underwent colonoscopy, using the Kaiser Permanente California databases. We identified participants diagnosed with CRC from January 1, 2008 through December 31, 2015 from a cancer registry. Subjects were followed until initial colonoscopy, health plan disenrollment, death, or December 31, 2015. We reviewed records from 400 randomly selected persons without CRC (controls) for risk features to estimate the proportion who underwent screening colonoscopy. We performed logistic regression to identify variables associated with CRC detection. Of 257 subjects with a diagnosis of CRC, 102 did not have a record of CRC risk factors; 86 of these patients (84.3%) had non-advanced-stage CRC (no regional node spread/distant metastases). Of the 400 controls, 299 (74.75%; 95% CI, 70.49%-79.01%) lacked CRC risk features, enabling estimation that 72,263 (mean age, 57.5 ± 7.0 y; 54.5% female) had undergone screening colonoscopy. CRC was detected in 1.4 per 1000 persons after 1 FIT, without association with increasing FITs (P = .97). CRC was detected in 1.3 per 1000 persons in 2 y or less after the last FIT and in 4.4 per 1000 persons more than 2 y after the last FIT (P < .001). When the last FIT was 2 y earlier or less, CRC increased from 0.7 per 1000 persons age 50-59 y to 3.1 per 1000 persons older than 70 y. Age and time from the last FIT were associated with CRC, with adjusted odds ratios of 1.08 (95% CI, 1.05-1.11) and 2.76 (95% CI, 1.28-5.95), respectively. In asymptomatic, average-risk persons with a negative result from a FIT, CRC is infrequent within 2 y after the last FIT (especially for persons younger than 60 y), usually non-advanced, and unrelated to the number of FITs performed.

Knowledge, attitude, and perceived barriers regarding colorectal cancer screening practices and risk factors among medical students in Saudi Arabia

BackgroundColorectal cancer (CRC) is a major health problem. It is the third most diagnosed common tumour and the fourth leading cause of cancer-related deaths worldwide. Early screening has been shown to decrease the incidence of CRC cancer and decrease mortality. In Saudi Arabia (SA), there is no national policy for CRC screening despite the growing incidence of the disease. This study investigated the knowledge of risk factors for CRC, recommendations for screening, and attitudes and barriers towards screening among medical students.MethodsData was collected using a self-administered valid and reliable questionnaire consisting of demographic characteristics, knowledge, attitude, and barriers measurements completed by 581 medical students from two Saudi schools. Frequencies and mean scores of knowledge and attitude were determined. The likelihood of students having adequate knowledge of CRC risk factors and screening modalities was estimated using multivariate logistic regression analysis.ResultsKnowledge of the risk factors for CRC and screening modalities, and attitude towards screening were poor in 52.47 and 57.83% of the surveyed medical students; respectively. Higher level of medical education (OR = 3.23; 95% CI: 2.01–5.18) and a positive attitude towards CRC screening (OR = 2.74; 95% CI: 1.86–4.03) were independent predictors of higher knowledge levels. Lack of awareness about CRC and screening modalities among patients, and shortage of specialized healthcare providers were barriers independently associated with low knowledge levels.ConclusionsSaudi medical students have limited knowledge of CRC risk factors of and a poor attitude towards CRC screening. These results contribute to our understanding of missed teaching opportunities in Saudi medical schools and suggest intervening at the medical school, clinical practice, and population levels to increase CRC screening practices.

A Rural-Urban Comparison of Knowledge, Risk- Factors and Preventive Practices for Colorectal Cancer among Adults in Lagos State

Objective:To assess and compare the knowledge, risk-factors and preventive practices for colorectal cancer among adults in Lagos State. Material and methods:This was a cross-sectional comparative study conducted among 607 respondents selected from one rural (Ikorodu) and one urban (Surulere) LGA using a multistage sampling technique. Data were collected using a pre-tested questionnaire administered by trained research assistants between April and September 2017.Data was analyzed using Epi-info statistical software version 3.5.1. Univariate and bivariate analysis was carried out and -p values of ≤0.05 were considered statistically significant. Results:Respondents’ knowledge of colorectal cancer was generally low, (rural-78.2%, urban- 62.2%, p<0.001). Urban respondents were significantly more knowledgeable than their rural counterparts (rural- 21.8%, urban- 37.8%, p<0.001). The presence of CRC risk-factors were higher among urban respondents (urban-49.3%, rural-42.6%, p= 0.09), however this difference was not statistically significant. Preventive practices were generally poor in both groups, although more (18.1%) urban respondents significantly took preventive actions against CRC compared with rural (6.9%) respondents, (p<0.001).Increasing levels of education were significantly associated with higher knowledge level in both groups (p≤0.05). Conclusion:The level of knowledge of colorectal cancer was generally poor in both groups but significantly poorer among rural respondents. The presence of known risk- factor was higher among urban respondents while preventive practices were poor in both groups.

Prevalence of polyps ≥6 mm on follow-up CT colonography in a cohort with no significant colon polyps at baseline

AimAssess the prevalence of neoplasia ≥6 mm at repeat CT colonoscopy (CTC) in individuals with no significant lesions at baseline. MethodsIndividuals aged ≥18 years, with/without CRC risk factors, with no polyps ≥6 mm on baseline CTC (negative baseline) who underwent repeat CTC in a large HMO from 2001 to 2011 were retrospectively identified. Studies were reviewed by board-certified radiologists with experience interpreting CTC. Demographic details, CRC risk factors, and the number, size, and location of incident lesions were noted. Findings were classified using the C-RADS scale. Lesion prevalence at CTC-2 was determined, and study interval and risk characteristics of patients with- and without findings were compared. ResultsOur study included 636 individuals (369 men [58.0%]; mean age 59.9 years) with negative baseline CTC who underwent repeat CTC after a mean 4.6 year interval (SD 1.6 years). At baseline, 469/636 (73.7%) were at average risk for CRC; 418 remained at average risk for CTC-2 with 51 (8.0%) developing new risk factors in the interval between studies. At CTC-2, 47 participants (7.4%) presented 52 significant neoplasia: 35 polyps 6–9 mm, 14 polyps ≥10 mm, and 3 masses in 3/636 participants (0.47%). 2/3 masses, 6/14 polyps ≥10 mm (42.9%), and 12/25 polyps 6–9 mm (48.0%) were in individuals with risk factors for CRC. Histopathology was available for 12/52 lesions (23.1%): 8 tubular adenomas, 2 villous adenomas, 1 hamartomatous polyp, 1 case of normal tissue. ConclusionA mean 4.6 years after negative-baseline CTC, neoplasia ≥6 mm were seen in 7.4% of participants, including masses in 0.47%, supporting recommendations for a 5-year study interval.

A patient-oriented clinical decision support system for CRC risk assessment and preventative care

BackgroundColorectal Cancer (CRC) is the third leading cause of cancer death among men and women in the United States. Research has shown that the risk of CRC associates with genetic and lifestyle factors. It is possible to prevent or minimize certain CRC risks by adopting a healthy lifestyle. Existing Clinical Decision Support Systems (CDSS) mainly targeted physicians as the CDSS users. As a result, the availability of patient-oriented CDSS is limited. Our project is to develop patient-oriented CDSS for active CRC management.MethodsWe implemented an online patient-oriented CRC CDSS for the public to learn about CRC, assess CRC risk levels, understand personalized CRC risk factors, and seek professional advices for people with CRC concerns. The system is implemented based on the Django Model-View-Controller (MVC) framework with an extensible background MySQL database. A CRC absolute risk prediction model is applied to calculate the personalized CRC risk score with a user-friendly web survey. An interactive dashboard using advanced data visualization technics will display and interpret the risk scores and factors. Based on the risk assessment, a structured decision tree algorithm will provide the recommendations on customized CRC screening methods. The CDSS also provides a search function for preferred providers and hospitals based on geographical information and patient preferences.ResultsA prototype of the patient-oriented CRC CDSS has been developed. It provides an open assessment of potential CRC risks via an online survey. The CRC risk predictive model has been implemented. The prediction outcomes of risk levels and factors are presented to the users through a personalized interactive visualization interface, to guide the public on how to reduce the CRC risks by changing their living styles (such as smoking and drinking) and diet characteristics (such as consumptions of red meat and milk). The CDSS will also provide customized recommendations on screening methods based on the corresponding risk factors. For users seeking professional clinicians, the CDSS also provides a convenient tool for searching nearby hospitals and available doctors based on the location preferences and providers characteristics (such as gender, language, and specialty).ConclusionsThis CRC CDSS prototype provides a patient-friendly interface for CRC risk assessment and gives a personalized interpretation on important CRC risk factors. It is a useful tool to educate the public on CRC, to provide guidance on minimizing CRC risks, and to promote early CRC screening that reduces the CRC occurrences.

A Web-based survey among adults aged 40–54 years was time effective and yielded stable response patterns

ObjectiveWe want to present information about response patterns obtained by Web-based survey in a large-scale epidemiological study. Study Design and SettingWithin the RAPS (Risk Adapted Prevention Strategies for colorectal cancer [CRC]) study, we invited 160,000 randomly selected persons aged 40–54 years in three large German cities from 2015 to 2016 to complete a Web-based questionnaire on CRC risk factors and screening (97 items, average time for completion 15 minutes). Invitation letters and up to two reminder letters were sent to each individual. ResultsA total of 21.4% of women and 18.0% of men completed the questionnaire. Overall cumulative response rates were 7.5%, 14.3%, and 19.6% after the initial invitation letter, and the first and second reminder, respectively, with prevalence of and associations of key epidemiological parameters (such as family history of cancer, previous colonoscopy, etc.) being remarkably stable across waves of responses. For example, the sex and age distribution of the sample did not change with additional answers gained from additional letters. ConclusionWeb-based questionnaires are feasible, cost-effective, and time effective in the setting of large-scale epidemiological studies. Although response patterns were remarkably stable over several rounds of reminders with substantially increasing cumulative response rates, future research should address possibilities to further enhance response rates.

Trends in colorectal cancer incidence among younger adults-Disparities by age, sex, race, ethnicity, and subsite.

Millennials (ages 18‐35) are now the largest living generation in the US, making it important to understand and characterize the rising trend of colorectal cancer incidence in this population, as well as other younger generations of Americans. Data from the New Jersey State Cancer Registry (n = 181 909) and Surveillance, Epidemiology, and End Results program (n = 448 714) were used to analyze invasive CRC incidence trends from 1979 to 2014. Age, sex, race, ethnicity, subsite, and stage differences between younger adults (20‐49) and screening age adults (≥50) in New Jersey (NJ) were examined using chi‐square; and, we compared secular trends in NJ to the United States (US). Whites, men, and the youngest adults (ages 20‐39) are experiencing greater APCs in rectal cancer incidence. Rates among younger black adults, overall, were consistently higher in both NJ and the US over time. When compared to older adults, younger adults with CRC in NJ were more likely to be: diagnosed at the late stage, diagnosed with rectal cancer, male, non‐white, and Hispanic. Invasive CRC incidence trends among younger adults were found to vary by age, sex, race, ethnicity, and subsite. Large, case‐level, studies are needed to understand the role of genetics, human papillomavirus (HPV), and cultural and behavioral factors in the rise of CRC among younger adults. Provider and public education about CRC risk factors will also be important for preventing and reversing the increasing CRC trend in younger adults.