Association of colorectal adenoma with components of metabolic syndrome

Interaction of Colorectal Neoplasm Risk Factors and Association with Metabolic Health Status Focusing on Normal Waist-to-Hip Ratio in Adults

BACKGROUND

We aimed to evaluate the interaction between colorectal adenoma risks among asymptomatic individuals in terms of metabolic health status and obesity, and examine the normal waist-to-hip ratio (WHR) in adults with colorectal adenoma risk.

METHODS

A cross-sectional, retrospective study was conducted at MacKay Memorial Hospital involving 16,996 participants who underwent bidirectional gastrointestinal endoscopy between 2013 and 2023. The study recorded important clinicopathological characteristics, including age, body mass index and WHR, Framingham Risk Score (FRS), blood glucose level, and Helicobacter pylori (H. pylori) infection status.

RESULTS

Multivariate logistic regression analysis demonstrated that elevated hemoglobin A1C (HbA1c), increased FRS, positive H. pylori infection, and WHR ≥ 0.9 are independent risk factors for colorectal adenoma. In examining the interaction between FRS and WHR using multivariate logistic regression to evaluate adenoma risk, the OR for the interaction term was 0.95, indicating a decline in adenoma risk when considering the interaction between these two factors. Incorporating HbA1c into the analysis, evaluating the interaction between FRS and WHR still demonstrated a statistically significant impact on adenoma risk (OR 0.96, p < 0.001). Participants with WHR < 0.9, elevated FRS, positive H. pylori infection, and increased HbA1c levels were associated with a higher risk of colorectal adenoma formation. Remarkably, the increased risk of adenoma due to rising HbA1c levels was statistically significant only for those with a WHR < 0.9.

CONCLUSIONS

An increase in FRS and HbA1c or a positive H. pylori infection still warrants vigilance for colorectal adenoma risk when WHR is 0.9. These factors interacted with each other and were found to have a minimal decline in adenoma risk when considering the interaction between WHR and FRS.

MAFLD with central obesity is associated with increased risk of colorectal adenoma and high-risk adenoma

OBJECTIVE

To analyze the risk factors associated with colorectal adenoma and to investigate the associations of metabolism-related fatty liver disease (MAFLD) with obesity, colorectal adenoma and high-risk adenoma.

METHODS

A total of 1395 subjects were enrolled and divided into a colorectal adenoma group (593 subjects) and a control group (802 subjects) according to the inclusion and exclusion criteria. The characteristics of patients in the colorectal adenoma group and the control group were compared by the chi-square test. Univariate and multivariate logistic analyses were used to analyze independent risk factors and associations with different MAFLD subtypes. Colorectal adenoma characteristics and the proportion of patients with high-risk colorectal adenoma were also compared.

RESULTS

High-density lipoprotein (HDL-C) was significantly lower in patients in the colorectal adenoma group than in those in the control group (P < 0.001). Logistic regression analysis revealed that age, obesity status, central obesity status, hypertension status, diabetes status, fatty liver status, smoking history, BMI, waist circumference, triglyceride level, HDL-C level, fasting blood glucose level and degree of hepatic steatosis were all independent risk factors for colorectal adenoma. Notably, MAFLD was associated with a significantly increased risk of colorectal adenoma in patients with central obesity (P < 0.001). In addition, obesity, central obesity, diabetes, fatty liver and degree of hepatic steatosis were all shown to be independent risk factors for high-risk colorectal adenoma. In addition, a greater proportion of MAFLD patients with central obesity than those without central obesity had high-risk colorectal adenoma.

CONCLUSION

MAFLD and central obesity are independently associated with the development of colorectal adenoma. MAFLD with central obesity is associated with an increased risk of colorectal adenoma and high-risk adenoma.

Insulin levels are associated with risk of colon adenoma and not nonadenomatous polyps: A retrospective, hospital-based study

Recently, the prevalence of colorectal cancer has been increasing in Korea. Several studies have reported that adenomatous polyps, known as precancerous lesions, are associated with increased blood insulin levels. The principal objective of the present study was to examine the correlation between insulin levels and colon polyps in subjects without a history of diabetes or colorectal cancer. From January 2, 2018 to December 31, 2019, 3277 adults who visited the University Hospital Health Examination Center and underwent colonoscopy were included in this study. Insulin, glycated hemoglobin (HbA1c), and fasting blood glucose levels were measured, and past medical history, alcohol consumption, smoking, and physical activity were assessed using self-administered questionnaires. Among the 3277 subjects, the prevalence of adenomatous and nonadenomatous lesions were 22.2% and 11.5%, respectively. The mean values of insulin, HbA1c, and fasting blood glucose were significantly increased in the adenomatous and nonadenomatous polyp groups compared to the normal group. Logistic regression analysis showed that the risk of adenoma (odds ratio [OR] 1.483; 95% confidence interval [CI], 1.170-1.878) and nonadenomatous polyps (OR 1.415; 95% CI, 1.038-1.929) were increased in the high insulin level group (≥7.36 uIU/mL), and only the risk of adenoma (OR 1.312; 95% CI, 1.003-1.718) was significantly higher after adjustment for disturbance variables. This study suggests that an increase in insulin levels is a significant risk factor for colon adenoma.

UHPLC-HRMS–based serum lipisdomics reveals novel biomarkers to assist in the discrimination between colorectal adenoma and cancer

The development of a colorectal adenoma (CA) into carcinoma (CRC) is a long and stealthy process. There remains a lack of reliable biomarkers to distinguish CA from CRC. To effectively explore underlying molecular mechanisms and identify novel lipid biomarkers promising for early diagnosis of CRC, an ultrahigh-performance liquid chromatography tandem high-resolution mass spectrometry (UHPLC-HRMS) method was employed to comprehensively measure lipid species in human serum samples of patients with CA and CRC. Results showed significant differences in serum lipid profiles between CA and CRC groups, and 85 differential lipid species (P &lt; 0.05 and fold change &gt; 1.50 or &lt; 0.67) were discovered. These significantly altered lipid species were mainly involved in fatty acid (FA), phosphatidylcholine (PC), and triacylglycerol (TAG) metabolism with the constituent ratio &gt; 63.50%. After performance evaluation by the receiver operating characteristic (ROC) curve analysis, seven lipid species were ultimately proposed as potential biomarkers with the area under the curve (AUC) &gt; 0.800. Of particular value, a lipid panel containing docosanamide, SM d36:0, PC 36:1e, and triheptanoin was selected as a composite candidate biomarker with excellent performance (AUC = 0.971), and the highest selected frequency to distinguish patients with CA from patients with CRC based on the support vector machine (SVM) classification model. To our knowledge, this study was the first to undertake a lipidomics profile using serum intended to identify screening lipid biomarkers to discriminate between CA and CRC. The lipid panel could potentially serve as a composite biomarker aiding the early diagnosis of CRC. Metabolic dysregulation of FAs, PCs, and TAGs seems likely involved in malignant transformation of CA, which hopefully will provide new clues to understand its underlying mechanism.

Serum Untargeted UHPLC-HRMS-Based Lipidomics to Discover the Potential Biomarker of Colorectal Advanced Adenoma

Background

As a key precancerous lesion, colorectal advanced adenoma (CAA) is closely related to the occurrence and development of colorectal cancer (CRC). Effective identification of CAA-related biomarkers can prevent CRC morbidity and mortality. Lipids, as an important endogenous substance, have been proved to be involved in the occurrence and development of CRC. Lipidomics is an advanced technique that studies lipid metabolism and biomarkers of diseases. However, there are no lipidomics studies based on large serum samples to explore diagnostic biomarkers for CAA.

Methods

An integrated serum lipid profile from 50 normal (NR) and 46 CAA subjects was performed using ultra-high performance liquid chromatography tandem high-resolution mass spectrometry (UHPLC-HRMS). Lipidomic data were acquired for negative and positive ionization modes, respectively. Differential lipids were selected by univariate and multivariate statistics analyses. A receiver operator characteristic curve (ROC) analysis was conducted to evaluate the diagnostic performance of differential lipids.

Results

A total of 53 differential lipids were obtained by combining univariate and multivariate statistical analyses (P < 0.05 and VIP > 1). In addition, 12 differential lipids showed good diagnostic performance (AUC > 0.90) for the discrimination of NR and CAA by receiver operating characteristic curve (ROC) analysis. Of them, the performance of PC 44:5 and PC 35:6e presented the outstanding performance (AUC = 1.00, (95% CI, 1.00–1.00)). Moreover, triglyceride (TAG) had the highest proportion (37.74%) as the major dysregulated lipids in the CAA.

Conclusion

This is the first study that profiled serum lipidomics and explored lipid biomarkers with good diagnostic ability of CAA to contribute to the early prevention of CRC. Twelve differential lipids that effectively discriminate between NR and CAA serve as the potential diagnostic markers of CAA. An obvious perturbation of TAG metabolism could be involved in the CAA formation.

Metabolic syndrome and colorectal adenoma risk: A systematic review and meta‑analysis

OBJECTIVE

Whether metabolic syndrome is a risk factor of colorectal adenoma has spurred debate. We systematically meta-analyzed all clinical studies associated with metabolic syndrome (MetS)/metabolic components and colorectal adenoma risk and quantified the dose-response association between them, aiming to provide more clues for better decision-making.

METHODS

We searched PubMed, EMBASE, and Cochrane Library through June 2020 for clinical studies of MetS and colorectal adenoma risk. RevMan 5.3 software and STATA 12.0 software were employed for meta-analysis.

RESULTS

Seventeen studies representing 44,336 participants were eligible for analysis. The overall meta-analysis showed that MetS patients had increased risk of colorectal adenoma (OR: 1.39, 95% CI 1.24-1.57; P < 0.05). Dose-response analysis presented that every increased number of Mets components was associated with a 8% increment of colorectal adenoma risk(OR: 1.08; 95% CI: 1.04-1.11). Subgroup analysis by age revealed a higher colorectal adenoma risk in MetS patients 50 years or older (OR 1.46; 95% CI 1.21-1.76; P < 0.0001), rather than MetS patients younger than 50 years old (OR 1.23; 95% CI 0.95-1.59; P = 0.11).When stratified by sex, the analysis revealed a higher risk of colorectal adenoma in male MetS patients (OR 1.32; 95% CI 1.15-1.53; P = 0.0001), rather than females (OR 1.65; 95% CI 0.90-3.02; P = 0.10). The analysis split by adenoma location showed that the right colon (OR 1.35; 95% CI 1.04-1.75; P = 0.03), instead of the left colon (OR 1.16; 95% CI 0.84-1.59; P = 0.37) or rectum(OR 1.26; 95% CI 0.89-1.78; P = 0.20), was the predilection site associated with increased colorectal adenoma risk in MetS patients.

CONCLUSIONS

Overall, our meta-analysis showed that MetS was associated with a higher risk of colorectal adenoma. MetS patients, especially old (≥50 years) male patients, should be a risk population for colorectal adenoma screening so that they can benefit from behavioural interventions that can help prevent the development of colorectal cancer.

Fecal Bacteria as Non-Invasive Biomarkers for Colorectal Adenocarcinoma

Colorectal adenocarcinoma (CRC) ranks one of the five most lethal malignant tumors both in China and worldwide. Early diagnosis and treatment of CRC could substantially increase the survival rate. Emerging evidence has revealed the importance of gut microbiome on CRC, thus fecal microbial community could be termed as a potential screen for non-invasive diagnosis. Importantly, few numbers of bacteria genus as non-invasive biomarkers with high sensitivity and specificity causing less cost would be benefitted more in clinical compared with the whole microbial community analysis. Here we analyzed the gut microbiome between CRC patients and healthy people using 16s rRNA sequencing showing the divergence of microbial composition between case and control. Furthermore, ExtraTrees classifier was performed for the classification of CRC gut microbiome and heathy control, and 13 bacteria were screened as biomarkers for CRC. In addition, 13 biomarkers including 12 bacteria genera and FOBT showed an outstanding sensitivity and specificity for discrimination of CRC patients from healthy controls. This method could be used as a non-invasive method for CRC early diagnosis.

Association of Helicobacter pylori infection with colorectal adenoma in the Chinese urban population: A cross-sectional study

OBJECTION

Helicobacter pylori (H. pylori) infection is considered to increase the risk of colorectal adenoma (CRA) and remains controversial. In this study, we aimed to evaluate the association between H. pylori infection and CAR in the Chinese urban population.

METHODS

A cross-sectional study of 301 urban adults, who underwent both screening colonoscopy and ¹³C urea breath test (¹³C UBT) from June 2018 to December 2019 at Geriatric Hospital of Nanjing Medical University, was carried out to assess the relationship between H. pylori infection and CRA. All baseline characteristics and laboratory examination of subjects were collected and analyzed by specific personnel. The strength of association between H. pylori infection and the risk of CRA was described by multivariate logistic regression analyses to calculate the odds ratios (ORs) and 95% confidence interval (CIs).

RESULTS

Among the 301 subjects, 82 (27.24%) patients with H. pylori positive and 141 (46.84%) were confirmed to have CRA. Multivariate analysis adjusted for age, gender, uric acid and fatty liver revealed that H. pylori infection increased the risk of CRA significantly (adjusted OR 2.007, 95%CI 1.153-3.492, p = 0.014). In addition, the correlation between H. pylori infection and CRA persisted after further adjusting for metabolic variables (adjusted OR 2.029, 95%CI 1.161-3.544, p = 0.013) or other potential confounding factors related to CRA including smoking status, alcohol intake, cholecystitis and gallstone (adjusted OR 1.996, 95%CI 1.141-3.492, p = 0.015). In a gender-based subgroup analysis, H. pylori infection had an increased risk of CRA in male group (adjusted OR 1.997, 95%CI 1.010-3.945, p = 0.047).

CONCLUSIONS

H. pylori infection had a significant association with the risk of CRA in Chinese urban populations, which will provide new insights into selecting high-risk subjects with CRA.

Self-reported Metabolic Risk Factor Associations with Adenomatous, Sessile Serrated, and Synchronous Adenomatous and Sessile Serrated Polyps

Studies have found a positive association between metabolic risk factors, such as obesity and diabetes, and adenomatous polyps (AP). However, fewer studies have assessed the association between sessile serrated polyps (SSP) or synchronous diagnosis of APs and SSPs (synch polyps). Study participants (N = 1,370; ages 40-85) undergoing screening colonoscopy were enrolled between August 2016 and February 2020. Self-reported metabolic risk factors, including diabetes, hypertension, hyperlipidemia, and overweight/obesity, were evaluated for associations with new diagnoses of APs, SSPs, and synch polyps at the present colonoscopy. Average participant age was 60.73 ± 8.63 (SD) years; 56.7% were female and 90.9% white. In an assessment of individual metabolic risk factors, adjusted for age, sex, race, and smoking status, increased body mass index (BMI; overweight or obese vs. normal BMI of <25 kg/m2) was associated with an increased odds for new onset of colon APs (P trend < 0.001) as was a diagnosis of diabetes [adjusted conditional OR (aCOR) = 1.59 (1.10-2.29)]. No associations were seen between the metabolic risk factors and onset of SSPs. Being obese or hypertensive each increased the odds of new onset of synch polyps with aCOR values of 2.09 (1.01-4.32) and 1.79 (1.06-3.02), respectively. Self-reported risk factors may help assess polyp type risk. Because SSPs and synch polyps are rare, larger studies are needed to improve our understanding of the contribution of these factors to polyp risk. These data lead us to hypothesize that differences in observed metabolic risk factors between polyp types reflect select metabolic impact on pathways to colorectal cancer. PREVENTION RELEVANCE: Self-reported medical history provides valuable insight into polyp risk, potentially enabling the use of larger retrospective studies of colonoscopy populations to assess knowledge gaps. More aggressive colonoscopy screening, critical to colorectal cancer prevention, may be considered in populations of individuals with metabolic risk factors and modifiable lifestyle risk factors.

Scoring system for gallbladder polyps based on the cross-sectional area and patient characteristics

BACKGROUND

Current management guidelines for gallbladder polyps (GBPs) focus on a diameter more than 1 cm as an indication for cholecystectomy. Since most GBPs are not malignant, unnecessary cholecystectomies can lead to unnecessary complications and costs. We developed a score to identify true polyps focusing on their cross-sectional area (CSA).

METHODS

We retrospectively analyzed the demographic, clinical, laboratory, and sonographic characteristics of 522 patients with GBPs who had undergone cholecystectomy at our hospital between January 2010 and July 2020 (reference group). We used univariate analysis to compare these parameters between 88 true polyps and 434 pseudopolyps and multivariate logistic regression analysis to identify parameters to include in our scoring model. Receiver operating characteristics and area under the curve were used to identify cut-off values. The model was tested on a validation group of 98 patients.

RESULTS

In the multivariate analysis, a CSA >123 mm², positive blood flow signal, age >55.5 years, alanine aminotransferase (ALT) levels > 50 U/L, and an ALT/aspartate aminotransferase ratio > 0.77 were significantly associated with true polyps (odds ratio 6.528, 2.377, 2.617, 2.445, and -0.372, respectively). A prediction model based on cut-off values was used to distinguish a low-risk and high-risk GBP group; true polyps accounted for 6.54% and 58.72%, respectively (p < 0.001). In the low-risk and high-risk validation groups, true polyps comprised 12.35% and 82.35%, respectively (p < 0.001).

CONCLUSIONS

Our scoring system shows high accuracy and specificity in identifying true polyps and helps determine the need for surgical resection.

Influence of chronic comorbidities on periodic colorectal cancer screening participation: A population-based cohort study

Guidelines recommend regular screening for colorectal cancer (CRC). We examined the effects of chronic comorbidities on periodic CRC testing. Using linked healthcare databases from Ontario, Canada, we assembled a population-based cohort of 50-74-year olds overdue for guideline-recommended CRC screening between April 1, 2004 and March 31, 2016. We implemented multivariable recurrent events models to determine the association between comorbidities and the rate of becoming up-to-date with periodic CRC tests. The cohort included 4,642,422 individuals. CRC testing rates were significantly lower in persons with renal disease on dialysis (hazard ratio, HR 0.66, 95% confidence interval, CI 0.63 to 0.68), heart failure (HR 0.75, CI 0.75 to 0.76), respiratory disease (HR 0.84, CI 0.83 to 0.84), cardiovascular disease (HR 0.85, CI 0.84 to 0.85), diabetes (HR 0.86, 95% CI 0.86 to 0.87) and mental illness (HR 0.88, CI 0.87 to 0.88). There was an inverse association between the number of medical conditions and the rate of CRC testing (5 vs. none: HR 0.30, CI 0.25 to 0.36; 4 vs. none: HR 0.48, CI 0.47 to 0.50; 3 vs. none: HR 0.59, CI 0.58 to 0.60; 2 vs. none: HR 0.72, CI 0.71 to 0.72; 1 vs. none: HR 0.85, CI 0.84 to 0.85). Having both medical and mental comorbidities was associated with lower testing rates than either type of comorbidity alone (HR 0.72, CI 0.71 to 0.72). In summary, chronic comorbidities present a barrier to periodic guideline-recommended CRC testing. Exploration of cancer prevention gaps in these populations is warranted.

PCSK9 and cancer: Rethinking the link

BACKGROUND

Cancer is emerging as a major problem globally, as it accounts for the second cause of death despite medical advances. According to epidemiological and basic studies, cholesterol is involved in cancer progression and there are abnormalities in cholesterol metabolism of cancer cells including prostate, breast, and colorectal carcinomas. However, the importance of cholesterol in carcinogenesis and thereby the role of cholesterol homeostasis as a therapeutic target is still a debated area in cancer therapy. Proprotein convertase subtilisin/kexin type-9 (PCSK9), a serine protease, modulates cholesterol metabolism by attachment to the LDL receptor (LDLR) and reducing its recycling by targeting the receptor for lysosomal destruction. Published research has shown that PCSK9 is also involved in degradation of other LDLR family members namely very-low-density-lipoprotein receptor (VLDLR), lipoprotein receptor-related protein 1 (LRP-1), and apolipoprotein E receptor 2 (ApoER2). As a result, this protein represents an interesting therapeutic target for the treatment of hypercholesterolemia. Interestingly, clinical trials on PCSK9-specific monoclonal antibodies have reported promising results with high efficacy in lowering LDL-C and in turn reducing cardiovascular complications. It is important to note that PCSK9 mediates several other pathways apart from its role in lipid homeostasis, including antiviral activity, hepatic regeneration, neuronal apoptosis, and modulation of various signaling pathways. Furthermore, recent literature has illustrated that PCSK9 is closely associated with incidence and progression of several cancers. In a number of studies, PCSK9 siRNA was shown to effectively suppress the proliferation and invasion of the several studied tumor cells. Hence, a novel application of PCSK9 inhibitors/silencers in cancer/metastasis could be considered. However, due to poor data on effectiveness and safety of PCSK9 inhibitors in cancer, the impact of PCSK9 inhibition in these pathological conditions is still unknown.

SEARCH METHODS

A vast literature search was conducted to find intended studies from 1956 up to 2020, and inclusion criteria were original peer-reviewed publications.

PURPOSE OF REVIEW

To date, PCSK9 has been scantly investigated in cancer. The question that needs to be discussed is "How does PCSK9 act in cancer pathophysiology and what are the risks or benefits associated to its inhibition?". We reviewed the available publications highlighting the contribution of this proprotein convertase in pathways related to cancer, with focus on the potential implications of its long-term pharmacological inhibition in cancer therapy.

Non-Obese MAFLD Is Associated with Colorectal Adenoma in Health Check Examinees: A Multicenter Retrospective Study

Colorectal adenoma is linked to metabolic dysfunction. Metabolic dysfunction-associated fatty liver disease (MAFLD) has a precise definition and three subtypes, including non-obese MAFLD. We aimed to investigate the impact of MAFLD on the prevalence of colorectal adenoma by comparing it to non-alcoholic fatty liver disease (NAFLD) in health check-up examinees. This is a multicenter retrospective study. We enrolled 124 consecutive health check-up examinees who underwent colonoscopy. NAFLD and MAFLD were present in 58 and 63 examinees, respectively. Colorectal adenoma was diagnosed by biopsy. The impact of the MAFLD definition on the prevalence of colorectal adenoma was investigated by logistic regression, decision-tree, and random forest analyses. In logistic regression analysis, MAFLD was identified as the only independent factor associated with the presence of colorectal adenoma (OR 3.191; 95% CI 1.494–7.070; p = 0.003). MAFLD was also identified as the most important classifier for the presence of colorectal adenoma in decision-tree and random forest analyses (29 variable importance value). Among the three subtypes of MAFLD, non-obese MAFLD was the sole independent factor associated with the presence of colorectal adenoma (OR 3.351; 95% CI 1.589–7.262; p ≤ 0.001). Non-obese MAFLD was also the most important classifier for the presence of colorectal adenoma in decision-tree and random forest analyses (31 variable importance value). MAFLD, particularly non-obese MAFLD, is the most important factor associated with the presence of colorectal adenoma rather than NAFLD. Colonoscopy examination should be considered in patients with MAFLD, especially those who are non-obese.

Association of body fat distribution and metabolic syndrome with the occurrence of colorectal adenoma: A case-control study

OBJECTIVE

Visceral fat is thought to play different roles in the carcinogenesis of the colon with peripheral fat. Our aim was to evaluate the association of body fat distribution measured by bioelectrical impedance analysis (BIA) with the incidence of colorectal adenoma (CRA).

METHODS

A total of 410 asymptomatic participants who underwent a screening colonoscopy from July 2017 to December 2019 in our center were recruited, including 230 with adenomas and 180 without detected adenomas. The participants' body fat was measured by BIA, including their body fat mass (BFM), body fat percentage (BFP), and waist-to-hip ratio. Parameters of metabolic syndrome (MetS), including waist circumference, blood pressure, fasting blood glucose (FBG), blood level of triglyceride, cholesterol, and high-density lipoprotein were measured as well.

RESULTS

According to univariate analysis, age, male sex, body mass index, waist circumference, BFM, waist-to-hip ratio, blood pressure, and FBG were higher in the adenoma group than in the adenoma-free group (P < 0.05). On multivariate logistical analysis (adjusted for age, sex, smoking, drinking, and family history of CRC), a high waist-to-hip ratio was associated with a high incidence of CRA (odds ratio [OR] 1.84, 95% confidence interval [CI] 1.09-3.09, P = 0.02). Only a large waist circumference in components of MetS was independently associated with the incidence of CRA (OR 1.90, 95% CI 1.17-3.08, P = 0.01) in the multivariate analysis.

CONCLUSION

Body fat distribution is associated with CRA, central obesity is a core risk factor for CRA in MetS. Chinese Clinical Trial Registration number: ChiCTR-RRC-17010862.

Effect of ambient air pollution on the incidence of colorectal cancer among a diabetic population: a nationwide nested case-control study in Taiwan

OBJECTIVES

An increasing number of studies had shown that air pollution exposure may aggravate blood glucose control in patients with diabetes, an independent risk factor for colorectal cancer (CRC) proposed by some researchers. This study aimed to investigate the impact of exposure to ambient particulate matter with aerodynamic diameters ≤2.5 μm (PM_2.5) on the incidence of CRC among a diabetic population.

DESIGN

A nested case-control study.

SETTING

A subset data retrieved from the Taiwan's National Health Insurance Research Database.

PARTICIPANTS

We identified patients with newly diagnosed diabetes (n=1 164 962) during 1999-2013. Participants who had subsequently developed an incident of CRC were placed into the case group, while controls were matched to the cases at a 4:1 ratio by age, gender, date of diabetes diagnosis and the index date of CRC diagnosis.

METHODS AND OUTCOME MEASURES

All variables associated with the risk of CRC entered into a multinomial logistic regression model. The dose-response relationship between various average concentrations of PM_2.5 exposure and the incidence of CRC was estimated by logistic regression.

RESULTS

The study included a total of 7719 incident CRC cases matched with 30 876 controls of random sampling. The mean annual concentration of PM_2.5 was 35.3 µg/m³. After adjusting for potential confounders, a dose-response relationship was observed between the CRC risks and each interquartile increase of PM_2.5 concentration (Q1-Q2: 1.03 (0.95-1.11), Q2-Q3: 1.06 (0.98-1.15), ≥Q3: 1.19 (1.10-1.28) in model 2. The adjusted ORs (95% CI) of CRC incidence for each 10 µg/m³ increment of PM_2.5 was 1.08 (1.04-1.11). Moreover, a faster growing adapted Diabetes Complications Severity Index (aDCSI) score was noticed in CRC group compared with the controls, which also showed a significant association in our multivariate analysis (adjusted OR=1.28, 95% CI 1.18 to 1.38).

CONCLUSIONS

Long-term exposure to high concentrations of PM_2.5 may contribute to an increased incidence of CRC among diabetic populations.

Effect of Gender and Age on the Correlation between Helicobacter pylori and Colorectal Adenomatous Polyps in a Chinese Urban Population: A Single Center Study

Objectives

To investigate whether Helicobacter pylori (H. pylori) infection increases the risk of colorectal adenomatous polyp (CAP) in the context of age and gender.

Methods

A total of 563 study subjects (male/female, 368/195) from Beijing, China, with higher nursing level who underwent colonoscopy were retrospectively collected. H. pylori and CAP were detected by carbon-13 urea breath test and colorectal colonoscopy. The correlations between the number, size, distribution, and pathological grade of CAP and H. pylori infection were analyzed. The population was further stratified by age and gender in order to examine the risk of H. pylori and CAP in the context of these variables. The influence of H. pylori on the risk of CAP was assessed by logistic regression model.

Results

315 participants were diagnosed with CAP, and 207 participants were classified as healthy controls. The prevalence of H. pylori in the CAP group was significantly higher than that in the healthy control group (119/315, 37.8% versus 44/207, 21.3%) (p < 0.001). The proportion of H. pylori positive plus CAP in participants <50 years old was significantly higher than that in participants >50 years old (87/250; 34.8% versus 32/65; 49.2%) (p < 0.001). The proportion of H. pylori positive plus CAP in participants <50 years old was significantly higher than that in participants >50 years old (87/250; 34.8% versus 32/65; 49.2%) (p < 0.001). The proportion of H. pylori positive plus CAP in participants <50 years old was significantly higher than that in participants >50 years old (87/250; 34.8% versus 32/65; 49.2%) (p < 0.001). The proportion of H. pylori positive plus CAP in participants <50 years old was significantly higher than that in participants >50 years old (87/250; 34.8% versus 32/65; 49.2%) (

Conclusions

H. pylori is a major risk factor for CAP. Further studies are needed to assess the effects of H. pylori treatment or persistent infection on the occurrence or recurrence of CAP.

Potential anti-tumor effect of a nanoliposomal antiPCSK9 vaccine in mice bearing colorectal cancer

INTRODUCTION

Inhibition of proprotein convertase subtilisin/kexin 9 (PCSK9) is an effective therapeutic tool for lowering low-density lipoprotein cholesterol (LDL-C). There is no available evidence on the efficacy and safety of PCSK9 inhibitors in non-cardiovascular diseases, particularly cancer. The present study aimed to evaluate the effect of PCSK9 inhibition on cancer endpoints in mice bearing colon carcinoma, using a nanoliposomal antiPCSK9 vaccine.

MATERIAL AND METHODS

The prepared nanoliposomal antiPCSK9 vaccine was subcutaneously inoculated in BALB/c mice four times with a biweekly interval. Two weeks after the last booster, the vaccinated and unvaccinated mice were subcutaneously inoculated with CT26 colon cancer cells into the right flank. After the tumor mass became palpable, the mice were randomly divided into three groups: (1) PBS (untreated control), (2) vaccine group, and (3) pegylated liposomal doxorubicin (PLD; positive control) group. Body weight, tumor size and survival of mice were monitored for 50 days.

RESULTS

The nanoliposomal antiPCSK9 vaccine could efficiently provoke specific antibodies against PCSK9 in BALB/c mice and thereby reduced the plasma level and function of PCSK9. Tumor volume was 77% and 87.7% lower (p < 0.0001) in the vaccinated mice when compared with Doxil (liposomal doxorubicin) and control mice, respectively. Tumor size analysis showed that time to reach the endpoint of the vaccine group (47 ±11 days) was slightly but not significantly higher than PLD (46 ±2.6 days) and the control (43 ±12 days) groups. The tumor growth rates in the vaccine and PLD groups were reduced by 9.3% and 7.3, respectively, when compared with the control group. The vaccinated mice survived slightly but not significantly longer than PLD and the control mice. The median survival of the vaccine, PLD and control groups were 51, 45, and 41 days, respectively. The vaccinated mice's life was prolonged by 24.4% as compared with the control mice, while it was increased by 9.8% in the PLD group.

CONCLUSIONS

Our results revealed that PCSK9 inhibition not only exerted no harmful effects but also could moderately inhibit tumor growth, and improve lifespan and survival in mice bearing colon cancer.

Changes in lipids composition and metabolism in colorectal cancer: a review

Altered metabolism of lipids is currently considered a hallmark characteristic of many malignancies, including colorectal cancer (CRC). Lipids are a large group of metabolites that differ in terms of their fatty acid composition. This review summarizes recent evidence, documenting many alterations in the content and composition of fatty acids, polar lipids, oxylipins and triacylglycerols in CRC patients' sera, tumor tissues and adipose tissue. Some of altered lipid molecules may be potential biomarkers of CRC risk, development and progression. Owing to a significant role of many lipids in cancer cell metabolism, some of lipid metabolism pathways may also constitute specific targets for anti-CRC therapy.

Impact of sarcopenia on the risk of advanced colorectal neoplasia

BACKGROUND AND AIM

Sarcopenia is a pathological condition characterized by the progressive loss of muscle mass and increased amount of visceral fat. Recent evidence has revealed that sarcopenia is associated with certain diseases. However, the impact of sarcopenia on colorectal neoplasia has not been documented clearly. We studied the association between sarcopenia and advanced colorectal neoplasia in a large screening population.

METHODS

This cross-sectional study included 14 024 asymptomatic adults who underwent first-time screening colonoscopy. Sarcopenia (class II) was defined as an appendicular skeletal muscle mass (ASM)/bodyweight (%) value more than two standard deviations below the mean for healthy young adults. ASM was estimated using bioelectrical impedance analysis.

RESULTS

In a multivariable model adjusted for age, sex, obesity (body mass index ≥ 25), smoking status, alcohol intake, regular exercise, and family history of colorectal cancer, the odds ratio (OR) for advanced colorectal neoplasia on comparing participants with sarcopenia (class II) to those without sarcopenia (class I + II) was 1.52 (95% confidence interval [CI], 1.23-1.86). Further adjustment for metabolic parameters attenuated this association, but the association was still significant (OR, 1.34; 95% CI, 1.07-1.68). Furthermore, the multivariable (traditional risk factors)-adjusted OR associated with a 1% decrease on the introduction of ASM/weight% as a continuous variable in regression models was 1.04 (95% CI, 1.01-1.07) for advanced colorectal neoplasia.

CONCLUSIONS

Our findings indicate that sarcopenia is significantly and progressively associated with the risk of advanced colorectal neoplasia. This association might be explained by metabolic factors that could be potential mediators of the effect of sarcopenia.

Sex differences in associations among metabolic syndrome, obesity, related biomarkers, and colorectal adenomatous polyp risk in a Japanese population

To investigate sex differences in the associations among metabolic syndrome, obesity, adipose tissue-related biomarkers, and colorectal adenomatous polyps, a cross-sectional, multicenter study was conducted on 489 consecutive individuals who underwent their first colonoscopy at 3 hospitals. Plasma concentrations of adiponectin and leptin, as well as homeostatic model assessment of insulin resistance were also evaluated. The presence and number of adenomatous polyps, including advanced adenoma, were higher in men than in women. Metabolic syndrome was a risk factor for adenomatous polyps in both sexes. Large waist circumference was an independent risk factor for adenomatous polyps in men, and high BMI and large waist circumference were risk factors for adenomatous polyps in women. Interestingly, low BMI was associated with large adenomatous polyps (≥10 mm) and advanced adenoma, and waist-hip ratio was involved in proximal adenomatous polyp development only in women. In contrast, the highest quartile of leptin concentration had a 3.67-fold increased adenomatous polyp risk compared with the lowest quartile only in men. These results indicate that regarding colorectal pathogenesis, sex differences were identified in obesity but not in metabolic syndrome. Visceral obesity and a high serum leptin level may be risk factors for colorectal adenomatous polyp development in Japanese men.

Diabetes mellitus and hyperglycemia control on the risk of colorectal adenomatous polyps: a retrospective cohort study

Background

Colorectal cancer (CRC) develops from colorectal adenomatous polyps. This study is to determine if diabetes mellitus (DM), its treatment, and hemoglobin A1c (HbA1c) level are associated with increased risk of colorectal adenomatous polyps.

Methods

This was a retrospective cohort study that included patients who had at least one colonoscopy and were continuously enrolled in a single managed care organization during a 10-year period (2002–2012). Of these patients (N = 11,933), 1800 were randomly selected for chart review to examine the details of colonoscopy and pathology findings and to confirm the diagnosis of DM. Multivariable logistic regression analyses were performed to assess the associations between DM, its treatment, HbA1c level and adenomatous polyps (our main outcome).

Results

Among the total of 11,933 patients with a mean (standard deviation) age of 56 (± 8.8) years, 2306 (19.3%) had DM and 75 (0.6%) had CRC. Among the 1800 under chart review, 445 (24.7%) had DM, 11 (0.6%) had CRC and 537 (29.8%) had adenomatous polyps. In bivariate analysis, patients with DM had 1.45 odds of developing adenomatous polyps compared to those without DM. This effect was attenuated (odds ratio = 1.25, 95% CI: 0.96–1.62, p = 0.09) after adjusting for confounders such as age, gender, race/ethnicity, and body mass index. There was no significant association between type or duration of DM treatment or HbA1c level and adenomatous polyps.

Conclusions

Our study confirmed the known increased risk of adenomatous polyps with advancing age, male gender, Hispanic race/ethnicity and higher body mass index. Although it suggested an association between DM and adenomatous polyps, a statistically significant association was not observed after controlling for other potential confounders. Further studies with a larger sample size are needed to further elucidate this relationship.

Sex differences in associations among metabolic syndrome, obesity, related biomarkers, and colorectal adenomatous polyp risk in a Japanese population

To investigate sex differences in the associations among metabolic syndrome, obesity, adipose tissue-related biomarkers, and colorectal adenomatous polyps, a cross-sectional, multicenter study was conducted on 489 consecutive individuals who underwent their first colonoscopy at 3 hospitals. Plasma concentrations of adiponectin and leptin, as well as homeostatic model assessment of insulin resistance were also evaluated. The presence and number of adenomatous polyps, including advanced adenoma, were higher in men than in women. Metabolic syndrome was a risk factor for adenomatous polyps in both sexes. Large waist circumference was an independent risk factor for adenomatous polyps in men, and high BMI and large waist circumference were risk factors for adenomatous polyps in women. Interestingly, low BMI was associated with large adenomatous polyps (≥10 mm) and advanced adenoma, and waist-hip ratio was involved in proximal adenomatous polyp development only in women. In contrast, the highest quartile of leptin concentration had a 3.67-fold increased adenomatous polyp risk compared with the lowest quartile only in men. These results indicate that regarding colorectal pathogenesis, sex differences were identified in obesity but not in metabolic syndrome. Visceral obesity and a high serum leptin level may be risk factors for colorectal adenomatous polyp development in Japanese men.

Risk factors for intraepithelial neoplasia in patients with colorectal adenoma

AIM

To identify risk factors for intraepithelial neoplasia in colorectal adenoma by analyzing the clinical, endoscopic, and histopathological features of patients with colorectal adenoma.

METHODS

The clinical, endoscopic, and histopathological features of 657 patients with colorectal adenomatous polyps diagnosed by colonoscopy from January 2014 to April 2016 at Wuhan Union Hospital were retrospectively analyzed. The patients were divided into an intraepithelial neoplasia group and a non-intraepithelial neoplasia group according to the pathological diagnosis. χ² test was applied for univariate analysis between the two groups. Multivariate Logistic regression analysis was used to identify the risk factors for intraepithelial neoplasia and its malignancy degree in adenoma.

RESULTS

Most of colorectal adenomas were located in the left colon. The total incidence of intraepithelial neoplasia in colorectal adenoma was 22.68%. Age, polyp diameter, length of pedicle, and pathologic type were identified to be risk factors for intraepithelial neoplasia in adenoma, which could be incorporated in Logistic regression equation: logit P = -4.384 + 0.796X2 (age) + 0.324X3 (polyp diameter) + 1.296X4 (pedicle condition) + 0.944X7 (pathology type). Gender, age, and polyp size were identified to be risk factors for high-grade intraepithelial neoplasia in adenoma, which could be incorporated in Logistic regression equation: logit P = -2.939 + 1.036X1 (gender) + 0.853X2 (age) + 1.023X3 (polyp diameter). Total cholesterol (TC) and triglyceride (TG) in the low-grade and high-grade intraepithelial neoplasia groups were both significantly higher than those in the non-intraepithelial neoplasia group (P < 0.05). Low-density lipoprotein cholesterol (LDL-C) and uric acid (URIC) in the high-grade intraepithelial neoplasia group were both significantly higher than those in the non-intraepithelial neoplasia group (P < 0.05). There was no significant difference in the high-density lipoprotein cholesterol (HDL-C) or CEA among the three groups.

CONCLUSION

There is a greater risk of intraepithelial neoplasia among patients older than 40, having villous adenoma with diameter > 1 cm and pedicle. Male, polyp diameter, and age are risk factors for high-grade intraepithelial neoplasia in colorectal adenoma. The occurrence of intraepithelial neoplasia in adenoma may be related to blood lipids and uric acid levels.

The Fatty Liver Index: A Simple and Accurate Predictor of Colorectal Adenoma in an Average-Risk Population

BACKGROUND

Nonalcoholic fatty liver disease, the hepatic manifestation of metabolic syndrome, is associated with increased risk of colorectal adenoma, a precursor of colorectal cancer. Because nonalcoholic fatty liver disease and colorectal adenoma share many common risk factors of metabolic syndrome, the association between these 2 pathological findings has been investigated in multiple studies, but the results have been conflicting.

OBJECTIVE

The present study aimed to assess the relationship between the fatty liver index, a predictor of nonalcoholic fatty liver disease, and the prevalence of colorectal adenomas.

DESIGN

This is a retrospective observational study.

SETTINGS

This study was conducted at a single expert center.

PATIENTS

A total of 2976 consecutive subjects over 40 years of age undergoing routine checkups including abdominal ultrasonography and colonoscopy at Chung-Ang University Hospital Health Care Center were included.

MAIN OUTCOME MEASURES

The primary outcome measured was the prevalence of colorectal adenomas according to fatty liver index.

RESULTS

Among these subjects, 932 (31.3%) had colorectal adenoma, 691 (23.2%) had metabolic syndrome, and 1512 (50.8%) had fatty liver on ultrasonography. In multivariate analysis, fatty liver index ≥30 was associated with an increased risk of colorectal adenoma (OR, 1.269; 95% CI, 1.06-1.49; p = 0.008). The fatty liver index-high group (fatty liver index ≥30) had more colorectal adenomas and more advanced colorectal adenomas than the fatty liver index-low group (fatty liver index <30) (p < 0.001 and p = 0.042). The prevalence of colorectal adenomas increased with increasing quartile of fatty liver index (p < 0.05).

LIMITATIONS

The study was limited by a relatively healthy Asian population.

CONCLUSION

The high fatty liver index may be a useful predictor of colorectal adenoma. See Video Abstract at http://links.lww.com/DCR/A478.

Measurement of biological age may help to assess the risk of colorectal adenoma in screening colonoscopy

AIM

To investigate the clinical utility of biological age (BA) measurement in screening colonoscopy for the detection of colorectal adenomas in the average-risk population.

METHODS

A consecutive series of asymptomatic subjects aged ≥ 30 years who underwent colonoscopy in routine check-ups were enrolled. Colorectal adenoma was classified according to size, number, and location. BAs were calculated using the MEDIAGE^TM Biological Age Measurement System.

RESULTS

A total of 2696 subjects were investigated (1876 men and 820 women). The mean chronological age (CA) was 46.0 years and the mean BA was 44.7 years. Metabolic syndrome (MS) was diagnosed in 218 subjects (8.1%). The prevalence of overall colorectal adenoma was 23.1% (622/2,696). When the subjects were divided into four groups based on BA (≤ 39 years; 40-49 years; 50-59 years; ≥ 60 years), the prevalence of colorectal adenoma was increased as BA increased (P < 0.001). Colorectal adenoma located in the proximal colon was more prevalent in the BA-dominant group (BA-CA ≥ 5 years) than the CA-dominant group (CA-BA ≥ 5 years) (P = 0.034). When the subjects were categorized into four groups according to MS and age gap between BA and CA, the incidence of colorectal adenoma increased with MS and BA-dominance (P < 0.05).

CONCLUSION

Measurement of BA may help to assess the risk of colorectal adenoma in screening colonoscopy.

Abdominal fat distribution measured using computed tomography is associated with an increased risk of colorectal adenoma in men

A few studies have shown inconsistent results regarding the association between the visceral fat proportion and colorectal adenomas. We aimed to investigate the association between abdominal fat distribution measured by computed tomography (CT) and colon adenoma.A total of 336 participants underwent physical examination, blood tests, colonoscopy, and abdominal computed tomography at Chung-Ang University Hospital. The associations between the obesity indicies (body mass index, visceral fat area (VFA), subcutaneous fat area (SFA), VFA-to-SFA ratio (VFA/SFA), and colorectal adenomas were evaluated.Of 309 subjects, 119 patients (38.5%) had colorectal adenoma. Mean age and fasting plasma glucose were higher in the patients with colorectal adenoma (P < .05, respectively). The mean VFA (153.3 cm vs 131.4 cm, P < .01) and VFA/SFA (1.07 vs 0.92, P < .05) were higher in the adenoma group than in the nonadenoma group. Males had higher mean VFA and VFA/SFA (P < .001). The mean VFA, SFA, and VFA/SFA were not associated with the location, size, number, and advancement of colorectal adenoma. In multivariate analysis, colorectal adenoma was significantly associated with VFA rather than VFA/SFA. In addition, colorectal adenoma was significantly associated with VFA rather than VFA/SFA in the men. The VFA, SFA, and VFA/SFA were not associated with colorectal adenoma in the women.The VFA measured by using a CT scan was positively associated with the presence of colorectal adenoma, especially in men. Furthermore, average risk men with large visceral fat volume should be examined carefully in screening colonoscopy.

White Paper AGA: POWER - Practice Guide on Obesity and Weight Management, Education, and Resources

The epidemic of obesity continues at alarming rates, with a high burden to our economy and society. The American Gastroenterological Association understands the importance of embracing obesity as a chronic, relapsing disease and supports a multidisciplinary approach to the management of obesity. Because gastrointestinal disorders resulting from obesity are more frequent and often present sooner than type 2 diabetes mellitus and cardiovascular disease, gastroenterologists have an opportunity to address obesity and provide an effective therapy early. Patients who are overweight or obese already fill gastroenterology clinics with gastroesophageal reflux disease and its associated risks of Barrett's esophagus and esophageal cancer, gallstone disease, nonalcoholic fatty liver disease/nonalcoholic steatohepatitis, and colon cancer. Obesity is a major modifiable cause of diseases of the digestive tract that frequently goes unaddressed. As internists, specialists in digestive disorders, and endoscopists, gastroenterologists are in a unique position to play an important role in the multidisciplinary treatment of obesity. This American Gastroenterological Association paper was developed with content contribution from Society of American Gastrointestinal and Endoscopic Surgeons, The Obesity Society, Academy of Nutrition and Dietetics, and North American Society for Pediatric Gastroenterology, Hepatology and Nutrition, endorsed with input by American Society for Gastrointestinal Endoscopy, American Society for Metabolic and Bariatric Surgery, American Association for the Study of Liver Diseases, and Obesity Medicine Association, and describes POWER: Practice Guide on Obesity and Weight Management, Education and Resources. Its objective is to provide physicians with a comprehensive, multidisciplinary process to guide and personalize innovative obesity care for safe and effective weight management.

Gastrointestinal Complications of Obesity

Obesity usually is associated with morbidity related to diabetes mellitus and cardiovascular diseases. However, there are many gastrointestinal and hepatic diseases for which obesity is the direct cause (eg, nonalcoholic fatty liver disease) or is a significant risk factor, such as reflux esophagitis and gallstones. When obesity is a risk factor, it may interact with other mechanisms and result in earlier presentation or complicated diseases. There are increased odds ratios or relative risks of several gastrointestinal complications of obesity: gastroesophageal reflux disease, erosive esophagitis, Barrett's esophagus, esophageal adenocarcinoma, erosive gastritis, gastric cancer, diarrhea, colonic diverticular disease, polyps, cancer, liver disease including nonalcoholic fatty liver disease, cirrhosis, hepatocellular carcinoma, gallstones, acute pancreatitis, and pancreatic cancer. Gastroenterologists are uniquely poised to participate in the multidisciplinary management of obesity as physicians caring for people with obesity-related diseases, in addition to their expertise in nutrition and endoscopic interventions.

Effect of Insulin and Metformin Combination Treatment on Colon Adenoma and Advanced Adenoma Among DM II

BACKGROUND

The risk for colorectal adenoma and advanced adenoma among diabetes mellitus II (DM II) has been debated to differ with the type of anti-diabetic therapy. Insulin increases whereas metformin decreases the risk for colon adenoma (Ad) and advanced Ad (AAd). There have been no studies to evaluate the effect of combination treatment with insulin and metformin on colon Ad and AAd.

METHODS

The retrospective study included DM II patients undergoing screening colonoscopy. Subjects with incomplete colonoscopy, poor bowel preparation, personal history of colorectal cancer (CRC)/inflammatory bowel disease/hereditary nonpolyposis colorectal cancer/familial adenomatosis polyposis/colectomy or family history of CRC were excluded. Subjects were categorized into group 1 (insulin only), group 2 (metformin only), group 3 (combination of insulin and metformin) and group 4 (miscellaneous). Group 4 was excluded from data analysis. Ad detection rate (ADR) and advanced ADR (AADR) were calculated for each group.

RESULTS

Three hundred thirty-nine subjects composed the study group, with a mean age of 60.0 years and male to female ratio of 1:1.4. Composite ADR and AADR for study population was 35.1 and 15.3 %, respectively. Groups 1, 2 and 3 were composed of 88 (26.0 %), 211 (62.2 %) and 40 (11.8 %) subjects, respectively. ADR for groups 1, 2 and 3 was 40.9, 33.2 and 32.5 %, respectively (p value = 0.413). AADR for groups 1, 2 and 3 was 18.2, 15.2 and 10.0 %, respectively (p value = 0.489).

CONCLUSION

A decremental trend was observed in ADR and AADR across group 1, group 2 and group 3 (p value >0.05).

Parameters of Glucose and Lipid Metabolism Affect the Occurrence of Colorectal Adenomas Detected by Surveillance Colonoscopies

PURPOSE

Limited data are available regarding the associations between parameters of glucose and lipid metabolism and the occurrence of metachronous adenomas. We investigated whether these parameters affect the occurrence of adenomas detected on surveillance colonoscopy.

MATERIALS AND METHODS

This longitudinal study was performed on 5289 subjects who underwent follow-up colonoscopy between 2012 and 2013 among 62171 asymptomatic subjects who underwent an initial colonoscopy for a health check-up between 2010 and 2011. The risk of adenoma occurrence was assessed using Cox proportional hazards modeling.

RESULTS

The mean interval between the initial and follow-up colonoscopy was 2.2±0.6 years. The occurrence of adenomas detected by the follow-up colonoscopy increased linearly with the increasing quartiles of fasting glucose, hemoglobin A1c (HbA1c), insulin, homeostasis model assessment of insulin resistance (HOMA-IR), and triglycerides measured at the initial colonoscopy. These associations persisted after adjusting for confounding factors. The adjusted hazard ratios for adenoma occurrence comparing the fourth with the first quartiles of fasting glucose, HbA1c, insulin, HOMA-IR, and triglycerides were 1.50 [95% confidence interval (CI), 1.26-1.77; p(trend)<0.001], 1.22 (95% CI, 1.04-1.43; p(trend)=0.024), 1.22 (95% CI, 1.02-1.46; p(trend)=0.046), 1.36 (95% CI, 1.14-1.63; p(trend)=0.004), and 1.19 (95% CI, 0.99-1.42; p(trend)=0.041), respectively. In addition, increasing quartiles of low-density lipoprotein-cholesterol and apolipoprotein B were associated with an increasing occurrence of adenomas.

CONCLUSION

The levels of parameters of glucose and lipid metabolism were significantly associated with the occurrence of adenomas detected on surveillance colonoscopy. Improving the parameters of glucose and lipid metabolism through lifestyle changes or medications may be helpful in preventing metachronous adenomas.

Prevalence and risk factors of advanced colorectal neoplasms in asymptomatic Korean people between 40 and 49 years of age

BACKGROUND AND AIM

Current guidelines recommend colon cancer screening for persons aged over 50 years. However, there are few data on colorectal cancer screening in 40- to 49-year-olds. This study assessed the prevalence and risk factors of colorectal neoplasms in 40- to 49-year-old Koreans.

METHODS

We analyzed the results of screening colonoscopies of 6680 persons 40-59 years of age (2206 aged 40-49 and 4474 aged 50-59 years).

RESULTS

The prevalence of overall and advanced neoplasms in the 40- to 49-year age group was lower than in the 50- to 59-year age group (26.7% and 2.4% vs 37.8% and 3.5%, respectively). However, the prevalence of overall and advanced neoplasms increased to 39.1% and 5.4%, respectively, in 45- to 49-year-old individuals with metabolic syndrome. In the 40- to 49-year age group, age, current smoking, and metabolic syndrome were associated with an increased risk of advanced neoplasms (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.04-1.30; OR 3.12, 95% CI 1.20-8.12; and OR 2.00, 95% CI 1.09-3.67, respectively).

CONCLUSIONS

Individuals aged 40-49 years had a lower prevalence of colorectal neoplasms than those aged 50-59 years, but some 40- to 49-year-olds showed a similar prevalence to those aged 50-59 years. Age, current smoking habits, and metabolic syndrome are associated with an increased risk of advanced neoplasms in subjects aged 40-49 years. Further studies are needed to stratify the risks of colon cancer and guide targeted screening in persons younger than 50 years old.

Helicobacter pylori infection is an independent risk factor for colonic adenomatous neoplasms

PURPOSE

Helicobacter pylori infection is considered to have a positive association with colorectal neoplasms. In this study, we evaluated the association between H. pylori infection and colorectal adenomas, based on the characteristics of these adenomas in Korea, where the prevalence of H. pylori infection is high and the incidence of colorectal cancer continues to increase.

METHODS

The study cohort consisted of 4,466 subjects who underwent colonoscopy and esophagogastroduodenoscopy during screening (1,245 colorectal adenomas vs. 3,221 polyp-free controls). We compared the rate of H. pylori infection between patients with adenoma and polyp-free control cases, using multivariable logistic regression analysis.

RESULTS

The overall rate of positive H. pylori infection was higher in adenoma cases than in polyp-free control cases (55.0 vs. 48.5%, p < 0.001). The odds ratio (OR) of positive H. pylori infection in patients with adenoma compared to polyp-free controls was 1.28 (95% CI 1.11-1.47). The positive association of H. pylori infection with colorectal adenomas was more prominent in advanced adenomas (OR 1.84, 95% CI 1.25-2.70) and multiple adenomas (OR 1.72, 95% CI 1.26-2.35). Based on the location of these adenomas, the OR was significant only in patients with colonic adenomas (OR 1.31, 95% CI 1.13-1.52) and not in those with rectal adenoma (OR 0.85, 95% CI 0.58-1.24).

CONCLUSION

Helicobacter pylori infection is an independent risk factor for colonic adenomas, especially in cases of advanced or multiple adenomas, but not for rectal adenomas.

Prevalence of colorectal adenomas in asymptomatic young adults: a window to early intervention?

OBJECTIVE

The prevalence of colorectal adenoma is increasing in the average-risk population. However, little research is available on colorectal adenoma in young adults under age 40. The aim of this study was to investigate the prevalence and risk factors of colorectal adenoma in 20- to 39-year-old adults.

METHODS

We evaluated 4286 asymptomatic young adults aged 20 to 39 years who underwent first colonoscopy screening as part of an employer-provided health wellness programme at the Health Promotion Centre of Samsung Changwon Hospital, Korea from January 2011 to December 2013. Logistic regression modelling was used to identify risk factors for colorectal adenoma in asymptomatic young adults.

RESULTS

The prevalence of colorectal adenoma and advanced adenoma was 11.6% (497/4286) and 0.9% (39/4286), respectively. By age group, the prevalence of colorectal adenoma was 5.4% (33/608) in participants aged 20 to 29 years and 12.6% (464/3678) in participants aged 30 to 39. Colorectal adenoma was found in 13.1% (403/3072) of men and 7.7% (94/1214) of women. Increased risk of colorectal adenoma was associated with age over 30 years (OR, 2.37; 95% CI, 1.64-3.42), current smoker status (OR, 1.48; 95% CI, 1.14-1.91), and alcohol consumption (OR, 1.29; 95% CI, 1.03-1.63).

CONCLUSIONS

Our findings indicate that even if the prevalence of colorectal adenoma was low in young adults aged 20 to 39, being over 30, cigarette smoking, and alcohol consumption can affect young adults who have no other CRC risks.

Correlation between serum lipid levels and colorectal polyps

AIM

To explore the characteristics of serum lipids in patients with colorectal polyps.

METHODS

The levels of serum lipids were compared between patients with colorectal polyps and controls. Then, the levels of serum lipids were analyzed according to the different clinical characteristics of colorectal polyps.

RESULTS

The levels of triacylglycerol (TG) (1.62 ± 1.12), total cholesterol (5.16 ± 1.19), and low density lipoprotein-cholesterol (LDL-C) (3.36 ± 0.95) in the colorectal polyp group were significantly higher than those of the control group (t = 2.358, 4.437, and 5.137, P = 0.019, 0.000, and 0.000, respectively). The level of TG was significantly higher (t = 2.129, P = 0.035), and the level of high density lipoprotein-cholesterol (HDL-C) was significantly lower (t = -2.711, P = 0.008) in colorectal polyp patients with fatty liver than in those without. The level of LDL-C was significantly higher in colorectal polyp patients with gastric polyps than in those without (t = 2.201, P = 0.038). There were no significant differences in the 1evels of serum lipids between the adenoma group and non-adenoma group, between the villous adenoma group and non-villous adenoma group, between the left colon and rectum polyp group and right colon polyp group, or between the male and female groups. The incidence of fatty liver in patients with colorectal polyps was related to the incidence of hyperlipidemia.

CONCLUSION

There is a significant correlation between hypertriglyceride, hypercholesteremia, high LDL-C levels, and colorectal polyps. Hypertriglyceride and low HDL-C level may be related to colorectal polyps with fatty liver. High LDL-C level may be related to colorectal polyps with gastric polyps. The incidence of fatty liver in patients with colorectal polyps is related to the incidence of hyperlipidemia.

Background Colonic 18F-Fluoro-2-Deoxy-D-Glucose Uptake on Positron Emission Tomography Is Associated with the Presence of Colorectal Adenoma

¹⁸F-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) scan is used to evaluate various kinds of tumors. While most studies on PET findings of the colon focus on the colonic uptake pattern, studies regarding background colonic uptake on PET scan are rare. The purpose of this study was to identify the association between the background colonic uptake and the presence of colorectal adenoma (CRA), which is a frequent precancerous lesion. We retrospectively reviewed the medical records of 241 patients with gynecologic malignancy who had received PET or PET/computed tomography (CT) scan and colonoscopy at the same period as a baseline evaluation. Background colonic ¹⁸F-FDG uptake was visually graded and the maximal standardized uptake values (SUV_max) of 7 different bowel segments were averaged. In univariate analysis, older age at diagnosis (≥ 50 years, p = 0.034), overweight (BMI ≥ 23 kg/m², p = 0.010), hypercholesterolemia (≥ 200 mg/dL, p = 0.027), and high grade background colonic uptake (p = 0.009) were positively associated with the prevalence of CRA. By multiple logistic regression, high grade background colonic uptake was independently predictive of CRA (odds ratio = 2.25, p = 0.021). The proportion of CRA patients significantly increased as background colonic uptake grade increased from 1 to 4 (trend p = 0.015). Out of the 138 patients who underwent PET/CT, the proportion of CRA patients in the group with high SUV_max (> 2.25) was significantly higher than in the low SUV_max group (27.5% vs. 11.6%, p = 0.031). In conclusion, high grade of background colonic ¹⁸F-FDG uptake is significantly associated with the prevalence of CRA.

Metabolic syndrome is a risk factor for adenoma occurrence at surveillance colonoscopy: A single-center experience in Korea

We investigated the risk factors for adenoma occurrence at surveillance colonoscopy, especially focusing on patient characteristics, including metabolic factors.Surveillance colonoscopy intervals depend on baseline adenoma characteristics. However, patients' characteristics may also influence the occurrence of adenomas.Of 62,171 asymptomatic subjects who underwent colonoscopy for a health check-up between 2010 and 2011, 4869 subjects who underwent follow-up colonoscopy between 2012 and 2013 were included in this longitudinal study. The risk of adenoma occurrence was assessed using Cox proportional hazards modeling.Of 4869 subjects, 2827 (58.1%), 1619 (33.3%), and 423 (8.7%) were assigned to the normal, low-risk, and high-risk groups, respectively, according to baseline adenoma characteristics. The mean interval between initial and follow-up colonoscopy was 2.2 ± 0.6 years. Certain patient factors, including older age (≥50 years; adjusted hazard ratio [aHR], 2.08; 95% CI, 1.73-2.49), male sex (aHR, 1.69; 95% CI, 1.30-2.19), metabolic syndrome (MetS) (aHR, 1.28; 95% CI, 1.09-1.51), obesity (aHR, 1.17; 95% CI, 1.02-1.34), elevated fasting blood glucose levels (aHR, 1.37; 95% CI, 1.19-1.58), and elevated triglyceride levels (aHR, 1.19; 95% CI, 1.03-1.37), as well as baseline adenoma characteristics, were associated with a higher risk of adenoma occurrence at follow-up colonoscopy. The cumulative incidence of adenoma occurrence in the high-risk group was higher than that in the low-risk group, whereas the incidence in the high-risk group without MetS was comparable with that in the low-risk group with MetS.Patient characteristics, such as MetS, obesity, older age, and male sex, in addition to adenoma characteristics, were independent risk factors for adenoma occurrence at surveillance colonoscopy. These patient characteristics may be considered in surveillance colonoscopy intervals.

Metabolic Risk Profile and Cancer in Korean Men and Women

OBJECTIVES

Metabolic syndrome is a cluster of risk factors for type 2 diabetes mellitus and cardiovascular disease. Associations between metabolic syndrome and several types of cancer have recently been documented.

METHODS

We analyzed the sample cohort data from the Korean National Health Insurance Service from 2002, with a follow-up period extending to 2013. The cohort data included 99 565 individuals who participated in the health examination program and whose data were therefore present in the cohort database. The metabolic risk profile of each participant was assessed based on obesity, high serum glucose and total cholesterol levels, and high blood pressure. The occurrence of cancer was identified using Korean National Health Insurance claims data. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models, adjusting for age group, smoking status, alcohol intake, and regular exercise.

RESULTS

A total of 5937 cases of cancer occurred during a mean follow-up period of 10.4 years. In men with a high-risk metabolic profile, the risk of colon cancer was elevated (HR, 1.40; 95% CI, 1.14 to 1.71). In women, a high-risk metabolic profile was associated with a significantly increased risk of gallbladder and biliary tract cancer (HR, 2.05; 95% CI, 1.24 to 3.42). Non-significantly increased risks were observed in men for pharynx, larynx, rectum, and kidney cancer, and in women for colon, liver, breast, and ovarian cancer.

CONCLUSIONS

The findings of this study support the previously suggested association between metabolic syndrome and the risk of several cancers. A high-risk metabolic profile may be an important risk factor for colon cancer in Korean men and gallbladder and biliary tract cancer in Korean women.

Characteristics of and risk factors for colorectal neoplasms in young adults in a screening population

AIM: To investigate prevalence and risk factors for colorectal neoplasms in adults aged < 50 years, for whom screening is not recommended.

METHODS: This cross-sectional study compared prevalence and characteristics of colorectal and advanced adenomas in patients aged < 50 years who underwent colonoscopy screening with subjects aged ≥ 50 years. To evaluate risk factors for colorectal and advanced adenoma in young adults, we used multivariable logistic regression models. Colorectal neoplasm characteristics were evaluated and compared with those in older patients.

RESULTS: Among 2819 patients included, prevalences of colorectal adenoma and advanced adenoma were 19.7% and 1.5%, respectively. As patient age increased, so did the prevalence of colorectal neoplasm. However, prevalence of advanced adenoma did not differ between age-groups 45-49 years and ≥ 50 years (OR = 0.43, 95%CI: 0.17-1.07, P = 0.070). In younger age-group (< 50 years), colorectal adenoma was significantly associated with older age, waist circumference (OR = 1.72, 95%CI: 1.15-2.55, P = 0.008), and current smoking (OR = 1.60, 95%CI: 1.07-2.41, P = 0.023). Alcohol consumption was an independent risk factor for colorectal advanced adenoma (OR = 3.69, 95%CI: 1.08-12.54, P = 0.037). Multiple neoplasms and large neoplasms (≥ 1 cm) were more prevalent in subjects ≥ 50 years.

CONCLUSION: Current screening strategies for colorectal cancer may need to be amended to account for patient age, especially in young subjects with abdominal obesity, current smoking and alcohol consumption.

Screening for Colorectal Cancer Using a Multitarget Stool DNA Test: Modeling the Effect of the Intertest Interval on Clinical Effectiveness

BACKGROUND

A multitarget stool DNA (mt-sDNA) test was recently approved for colorectal cancer (CRC) screening for men and women, aged ≥ 50 years, at average risk of CRC. The guidelines currently recommend a 3-year interval for mt-sDNA testing in the absence of empirical data. We used clinical effectiveness modeling to project decreases in CRC incidence and related mortality associated with mt-sDNA screening to help inform interval setting.

MATERIALS AND METHODS

The Archimedes model (Archimedes Inc., San Francisco, CA) was used to conduct a 5-arm, virtual, clinical screening study of a population of 200,000 virtual individuals to compare the clinical effectiveness of mt-sDNA screening at 1-, 3-, and 5-year intervals compared with colonoscopy at 10-year intervals and no screening for a 30-year period. The study endpoints were the decrease in CRC incidence and related mortality of each strategy versus no screening. Cost-effectiveness ratios (US dollars per quality-adjusted life year [QALY]) of mt-sDNA intervals were calculated versus no screening.

RESULTS

Compared with 10-year colonoscopy, annual mt-sDNA testing produced similar reductions in CRC incidence (65% vs. 63%) and related mortality (73% vs. 72%). mt-sDNA testing at 3-year intervals reduced the CRC incidence by 57% and CRC mortality by 67%, and mt-sDNA testing at 5-year intervals reduced the CRC incidence by 52% and CRC mortality by 62%. At an average price of $600 per test, the annual, 3-year, and 5-year mt-sDNA screening costs would be $20,178, $11,313, and $7388 per QALY, respectively, compared with no screening.

CONCLUSION

These data suggest that screening every 3 years using a multitarget mt-sDNA test provides reasonable performance at acceptable cost.

The association between serum lipids and colorectal neoplasm: a systemic review and meta-analysis

OBJECTIVE

There have been inconsistent results published regarding the relationship between dyslipidaemia and an increased risk of colorectal neoplasia (CRN), including colorectal adenoma (CRA) and colorectal cancer (CRC). We conducted a meta-analysis to explore the relationship between dyslipidaemia and CRN.

DESIGN

We identified studies by performing a literature search using PubMed, EMBASE and the Science Citation Index through October 2013.

SETTING

We analysed thirty-three independent studies reporting the association between CRN and at least one of the selected lipid components, including total cholesterol (TC), TAG, HDL-cholesterol (HDL-C) and LDL-cholesterol (LDL-C).

SUBJECTS

CRN cases (n 21 809) were identified.

RESULTS

Overall, people with high levels of serum TAG (risk ratio (RR)=1.08; 95% CI 1.05, 1.12, P<0.00001) and LDL-C (RR=1.07; 95% CI 1.00, 1.14, P=0.04) presented an increased prevalence of CRN. Subgroup analyses revealed that high levels of serum TC (RR=1.04; 95% CI 1.01, 1.09, P=0.02), TAG (RR=1.06; 95% CI 1.03, 1.10, P=0.0009) and LDL-C (RR=1.11; 95% CI 1.04, 1.19, P=0.003) increased the risk of CRA but not of CRC. No association between serum HDL-C and risk for CRN (including CRA and CRC) was observed.

CONCLUSIONS

Both TAG and LDL-C were significantly associated with an increasing prevalence of CRN. High levels of serum TC, TAG and LDL-C were positively associated with CRA but not with CRC. No significant association was observed between levels of serum HDL-C and CRN.

Factors Determining Colorectal Cancer: The Role of the Intestinal Microbiota

The gastrointestinal tract, in particular the colon, holds a complex community of microorganisms, which are essential for maintaining homeostasis. However, in recent years, many studies have implicated microbiota in the development of colorectal cancer (CRC), with this disease considered a major cause of death in the western world. The mechanisms underlying bacterial contribution in its development are complex and are not yet fully understood. However, there is increasing evidence showing a connection between intestinal microbiota and CRC. Intestinal microorganisms cause the onset and progression of CRC using different mechanisms, such as the induction of a chronic inflammation state, the biosynthesis of genotoxins that interfere with cell cycle regulation, the production of toxic metabolites, or heterocyclic amine activation of pro-diet carcinogenic compounds. Despite these advances, additional studies in humans and animal models will further decipher the relationship between microbiota and CRC, and aid in developing alternate therapies based on microbiota manipulation.

Associations Between Parameters of Glucose and Lipid Metabolism and Risk of Colorectal Neoplasm

BACKGROUND

Diabetes and dyslipidemia have been linked to an increased risk of colorectal neoplasm (CRN). However, previous studies evaluating these associations have shown inconsistent results, and large-scale studies are few in number.

AIM

To investigate the associations between the parameters of glucose and lipid metabolism and the presence of CRN.

METHODS

A cross-sectional study was performed on 38,490 Korean adults aged ≥30 years undergoing their first colonoscopy as part of routine preventive health care between 2010 and 2011.

RESULTS

The prevalence of overall CRN increased with increasing levels of glucose, hemoglobin A1c (HbA1c), insulin, homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides, total cholesterol, low-density lipoprotein cholesterol (LDL-C), and apolipoprotein B (ApoB) and with decreasing level of apolipoprotein A1 (ApoA1). The adjusted prevalence ratios for overall CRN comparing the fourth with the first quartiles of fasting glucose, HbA1c, insulin, HOMA-IR, triglycerides, total cholesterol, LDL-C, ApoB, and ApoA-1 were 1.83 (95% CI 1.62-2.06), 1.17 (95% CI 1.03-1.33), 1.09 (95% CI 0.97-1.23), 1.22 (95% CI 1.08-1.37), 1.31 (95% CI 1.16-1.48), 1.19 (95 % CI 1.07-1.33), 1.38 (95% CI 1.23-1.54), 1.30 (95% CI 1.14-1.47), and 0.85 (95% CI 0.76-0.95), respectively. There was also a significant association between higher levels of glucose, LDL-C, and ApoB with a higher prevalence of advanced CRN. Moreover, the risk of CRN increased further in cases in which the parameters of glucose metabolism and lipid metabolism worsened simultaneously.

CONCLUSIONS

The levels of parameters of glucose and lipid metabolism are significantly associated with the prevalence of CRN. Altered glucose and lipid metabolism may contribute to the development of CRN.

Higher serum uric acid levels and advanced age are associated with an increased prevalence of colorectal polyps

The present study retrospectively analyzed the laboratory data of patients who had undergone a colonoscopy between April 2011 and March 2014, with the aim of assessing whether these variables could be used to predict the presence of colorectal polyps (CP). A total of 1,471 patients were enrolled (731 men, 68.5±10.8 years; 740 women, 66.7±10.8 years). One-way analysis of variance was performed to analyze the association between the presence of CP and a range of laboratory variables. Logistic regression analysis was performed to establish a regression equation to predict the presence of CP. Receiver-operator characteristics analysis was applied to investigate the performance of the regression equation. Patients with CP were older than those without CP (P<0.0001). Serum uric acid (UA) levels were higher in patients with CP, compared to those without CP (P=0.0007). To investigate the possibility that older age and higher UA levels could predict the presence of CP, logistic regression analysis was performed (P=0.0008). The regression equation was as follows: ln(p/1 - p) = 2.79015 - 0.01836 × age - 0.28542 × UA (mg/dl), where p indicates the presence of CP. Receiver-operator characteristic analysis showed the area under the curve to be 0.62092 and the threshold value of P was 0.4370. Sensitivity and specificity of the threshold value were 77.6 and 44.2%, respectively. Advanced age and higher serum UA levels were associated with the presence of CP. In conclusion, logistic regression analysis obtained a regression equation that predicted the presence of CP with a higher sensitivity, but poorer specificity, compared to fecal occult blood testing.

Plasma lipid levels and colorectal adenoma risk

PURPOSE

Abnormalities in lipid levels have been associated with colorectal neoplasm risk; however, few studies have adjusted for use of cholesterol-lowering medications. The objective of this study was to determine the association of plasma lipid levels with adenoma risk while accounting for statin medication use.

METHODS

We included 254 subjects with advanced adenoma, 246 with single small adenoma, 179 with multiple small adenoma cases, and 403 control participants in the Tennessee Colorectal Polyp Study who also had plasma lipid measurements performed. Data on the use of statin medications were available for 83.4% of these participants. The association between plasma lipids and adenoma risk was evaluated using logistic regression models.

RESULTS

Participants in the highest quartile of HDL cholesterol (range 52-106 mg/dl) had an adjusted odds ratio of 0.49 (95% CI 0.23, 1.07), 0.35 (95% CI 0.13, 0.91), and 0.22 (95% CI 0.09, 0.54) for single small, multiple small, and advanced adenomas compared to the lowest quartile (range 12-34 mg/dl), respectively. Participants with the highest quartile of triglyceride levels (range 178-721 mg/dl) had an adjusted odds ratio of 2.40 (95% CI 1.26, 4.55), 1.67 (95% CI 0.66, 4.23), and 2.79 (95% CI 1.25, 6.23) for single small, multiple small, and advanced adenoma, respectively, compared to the lowest quartile (range 40-84 mg/dl). When restricted to individuals with known statin medication use, adjusting for statin use did not appreciably affect these results.

CONCLUSION

We found a direct association between triglyceride plasma levels and an inverse association between plasma HDL cholesterol levels and adenoma risk. Both effects were not appreciably changed when accounting for the regular use of statin medication.

Genes associated with metabolic syndrome predict disease-free survival in stage II colorectal cancer patients. A novel link between metabolic dysregulation and colorectal cancer

Studies have recently suggested that metabolic syndrome and its components increase the risk of colorectal cancer. Both diseases are increasing in most countries, and the genetic association between them has not been fully elucidated. The objective of this study was to assess the association between genetic risk factors of metabolic syndrome or related conditions (obesity, hyperlipidaemia, diabetes mellitus type 2) and clinical outcome in stage II colorectal cancer patients. Expression levels of several genes related to metabolic syndrome and associated alterations were analysed by real-time qPCR in two equivalent but independent sets of stage II colorectal cancer patients. Using logistic regression models and cross-validation analysis with all tumour samples, we developed a metabolic syndrome-related gene expression profile to predict clinical outcome in stage II colorectal cancer patients. The results showed that a gene expression profile constituted by genes previously related to metabolic syndrome was significantly associated with clinical outcome of stage II colorectal cancer patients. This metabolic profile was able to identify patients with a low risk and high risk of relapse. Its predictive value was validated using an independent set of stage II colorectal cancer patients. The identification of a set of genes related to metabolic syndrome that predict survival in intermediate-stage colorectal cancer patients allows delineation of a high-risk group that may benefit from adjuvant therapy and avoid the toxic and unnecessary chemotherapy in patients classified as low risk. Our results also confirm the linkage between metabolic disorder and colorectal cancer and suggest the potential for cancer prevention and/or treatment by targeting these genes.

Pathway analysis of genome-wide association study and transcriptome data highlights new biological pathways in colorectal cancer

Colorectal cancer (CRC) is a common malignancy that meets the definition of a complex disease. Genome-wide association study (GWAS) has identified several loci of weak predictive value in CRC, however, these do not fully explain the occurrence risk. Recently, gene set analysis has allowed enhanced interpretation of GWAS data in CRC, identifying a number of metabolic pathways as important for disease pathogenesis. Whether there are other important pathways involved in CRC, however, remains unclear. We present a systems analysis of KEGG pathways in CRC using (1) a human CRC GWAS dataset and (2) a human whole transcriptome CRC case-control expression dataset. Analysis of the GWAS dataset revealed significantly enriched KEGG pathways related to metabolism, immune system and diseases, cellular processes, environmental information processing, genetic information processing, and neurodegenerative diseases. Altered gene expression was confirmed in these pathways using the transcriptome dataset. Taken together, these findings not only confirm previous work in this area, but also highlight new biological pathways whose deregulation is critical for CRC. These results contribute to our understanding of disease-causing mechanisms and will prove useful for future genetic and functional studies in CRC.

Cancer screenee cohort study of the National Cancer Center in South Korea

The Cancer Screenee Cohort Study was first established in 2002 by the National Cancer Center in South Korea to investigate all possible risk factors related to cancers and to expand biological specimen banking for the development of effective methodologies for cancer detection, diagnosis, and prevention. As of July in 2014, total 41,105 participants were enrolled in this cohort. Data were collected via questionnaire, clinical examination, cancer screening, and biological specimen testing including blood, urine, and exfoliated cervical cells. The highest incidence was found to be thyroid cancer, according to a nested case-control study that was linked to the National Cancer Registry information as of December 31, 2011. Case-control, cross-sectional, and cohort studies have been published using these data since 2009. Diet and nutrition was the most published topic, followed by genetics, hepatitis B virus and liver cancer screening, methodologies, physical activity, obesity, metabolic syndrome, smoking and alcohol consumption, and blood type. Evidence from the Cancer Screenee Cohort Study is highly anticipated to reduce the burden of cancer in the Korean population and aid in the detection, diagnosis, and prevention of cancer.

Association between family history of malignant neoplasm with colorectal adenomatous polyp in 40s aged relative person

PURPOSE

We assessed the association between a family history of malignancy and risk of colorectal adenoma among individuals aged 40-49 years.

METHODS

The study population consisted of subjects, aged in their 40s, who underwent colonoscopy. Their family histories of cancer were collected with a self-administered questionnaire. A logistic regression model was used to assess the association between a family history of cancer and the risk of colorectal polyp.

RESULTS

In total, 2275 participants were included in the study. Univariate analysis showed that old age, male sex, current cigarette smoking, BMI>25 kg/m(2), and a family history of colorectal cancer (CRC) were risk factors for the development of sporadic colorectal adenomatous polyps in these patients. A multivariate analysis showed that a family history of CRC or kidney cancer was associated with adenoma development. A family history of CRC was also a risk factor for advanced and multiple adenoma.

CONCLUSIONS

This study shows that a family history of CRC is a risk factor for advanced and multiple colorectal adenoma in people in their 40s. These results support earlier screening for colorectal neoplasms in individuals with a family history of CRC.