BMI and the risk of colorectal adenoma in African-Americans

Correlation Between Skeletal Muscle Mass and Different Pathological Types of Colorectal Polyp in Chinese Asymptomatic Population

Background

Low relative muscle mass was identified to be related to ascending risk of pre-cancerous polyps (adenoma) in recent cohort study. Our study aimed to dig out the correlation between muscle mass and different pathological types of colorectal polyps in Chinese asymptomatic population.

Methods

In all, 5923 adults were included. The effects of low skeletal muscle mass index (SMI) on colorectal polyp occurrence, including different pathological types, and the effects modification of age and BMI were analyzed using univariate and multivariate logistic regression.

Results

Lower SMI was connected with the lower occurrence of colorectal polyp (OR: 0.810, 95% CI: 0.683~0.960, p=0.015). Considering different pathological types of colorectal polyps, lower SMI was associated with lower occurrence of inflammatory polyp (OR: 0.633, 95% CI: 0.434~0.898, p=0.013), rather than conventional adenoma and serrated polyp (all p>0.05). Besides, SMI was positively related to the occurrence of 2 pathological types of colorectal polyp in males: inflammatory polyp (OR: 1.237, 95% CI: 1.058~1.444, p=0.007) and serrated polyp (OR: 1.288, 95% CI: 1.143~1.456, p<0.001). The interaction effect of BMI and SMI on occurrence of inflammatory polyp after adjusting age and smoking status was significant (p=0.015). For individuals with low SMI (compared with the normal SMI group), the incidence of inflammatory polyp was reduced from 8.95% to 3.50% in the low BMI quartile (Q1) in the adjusted model (OR of 0.332, 95% CI: 0.005-0.061, p<0.001). It was noticeable for males rather than females that individuals with colorectal polyps had higher levels of SMI (p=0.003). In addition, individuals with inflammatory polyps as well as serrated polyps possessed higher levels of SMI in males (all p<0.05).

Conclusion

Generally, especially in Chinese asymptomatic males, low SMI kept independent effect on the presence of inflammatory polyp and serrated polyp, rather than conventional adenoma.

Trends and Symptoms Among Increasing Proportion of African Americans with Early-Onset Colorectal Cancer over a 60-Year Period

BACKGROUND

The proportion of early onset colorectal cancer (EOCRC) is alarming in adults, including in African Americans (AA).

AIM

To investigate differences between EOCRC compared to late-onset colorectal cancer (LOCRC) among AA patients.

METHODS

This retrospective study reviewed demographic, clinical presentations, colonoscopy, and pathology reports of patients at Howard University Hospital from 1959 to 2023. The study included 176 EOCRC cases (< 45 years) and 2034 LOCRC cases (> 45 years).

RESULTS

Both EOCRC and LOCRC groups were predominantly AA (> 80%) with slightly more females (53%) than males. The mean age was 38 years for EOCRC and 66 years for LOCRC cases. EOCRC cases increased as a proportion of total detected CRC cases since 2010 (over 13%) after several decades of just above 6%. Family history of CRC in first degree relatives was higher among EOCRC (15.5% vs.3.4% in LOCRC patients, p < 0.01). Symptoms at presentation were prevalent in both EOCRC (93.8%) and LOCRC (92.6%). EOCRC patients exhibited higher incidence of abdominal pain (23.3% vs. 17.2%, p = 0.05) and changes in bowel habits (24.4% vs. 14%, p < 0.01) compared to LOCRC patients. Other symptoms such as melena, hematochezia, and weight loss were less prevalent in EOCRC patients. Comorbidities like hypertension (HTN), diabetes mellitus (DM), and inflammatory bowel disease (IBD) were less frequent among EOCRC patients. EOCRC was primarily observed in the sigmoid and rectosigmoid regions (p = 0.02). Metastasis at index colonoscopy was more prevalent with EOCRC compared to LOCRC (p = 0.04), with a higher proportion of patients at stage 3 cancer (p < 0.05). Significant differences were noted in the timeline for undergoing surgery after the diagnosis of colorectal cancer, with EOCRC patients taking longer than LOCRC patients (p = 0.03).

CONCLUSION

Presentation of EOCRC over LOCRC increased proportionally in our cohort since 2010 and is associated with family history, and symptoms such as abdominal pain and change in bowel habits. Likely because of age at presentation, there are less comorbidities among EOCRC patients who predominantly present in the outpatient setting, and more likely diagnosed with advanced stage lesions that are predominantly sigmoid or rectosigmoid. These findings are similar to observations seen in the general population with EOCRC, albeit African American patients have commonly had earlier age presentation of CRC than White American patients.

The Innate Immune System Surveillance Biomarker p87 in African Americans and Caucasians with Small High-Grade Dysplastic Adenoma [SHiGDA] and Right-Sided JAK3 Colon Mutations May Explain the Presence of Multiple Cancers Revealing an Important Minority of Patients with JAK3 Mutations and Colorectal Neoplasia

Colorectal cancer (CRC) outcomes in terms of incidence and mortality are significantly worse in African Americans than other Americans. While differences in primary preventions for neoplasia (diet, obesity remediation, aspirin prophylaxis) are being elucidated, genetic mutations affecting premalignant lesions and immune response mechanisms may possibly also explain the increased incidence and mortality, particularly from right-sided disease.

OBJECTIVE

Our team therefore examined colonic segments seeking to test the hypothesis that the immune response and somatic genetic profiles of the colonic anatomic segments may vary and thus account for variations in neoplasia risk among the various colonic segments revealing an antigenic relationship with precancerous lesions. The p87 antigenic field effect is recognized via Adnab-9 antibody immunohistochemistry to be significantly less in the right colon in African Americans, particularly in the cecum.

METHOD

Since small high-grade dysplastic adenomas (SHiGDA) likely missed by CRC screening may progress to cancer, we used Ion Torrent™ sequencing of DNA extracted from four normal colonic segments (two left-sided and two right) of patients with SHiGDAs. We also contrasted unique mutational fields in one patient with a large HiGDA (APC with unique mutations) and one patient who prospectively developed a SHiGDA (JAK3).

RESULT

The SHiGDA (small high-grade dysplastic polyp) patient was p87 negative for any extracted stool, saliva, or colonic effluent via ELISA (enzyme linked immunoadsorbant assay). Furthermore, mean values of expression in segments from the right colon were reduced with respect to the means obtained from the left segments in 233 patients evaluated for a p87 field effect. This has recently been shown to be the case in a large cohort of AA and Caucasian 2294 patients, possibly explaining the right-sided CRC disparity in African Americans and the subsequent increase in mortality. This field effect disparity is also true for two cancers contracted by the SHiGDa patient (lung and prostate).

CONCLUSION

Thus, this pilot study suggests that the reduction in p87 in the right colon is possibly correlated with JAK3 mutations. If confirmed, JAK3 mutations, known to be associated with immune aberrations, may provide a mechanistic explanation for the lack of a p87 (protein 87 kilodaltons) field in some patients with HGD polyps who might benefit from possible intervention such as more intensive screening. Limited microbiome studies were also performed on two patients with familial cancer syndromes and these compared favorably with controls available from the literature.

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.

Metabolic risk factors link unhealthy lifestyles to the risk of colorectal polyps in China

Colorectal cancer is the second leading cause of global cancer-related deaths, and its precursor lesions are colorectal polyps (CAP). The study aimed to explore the effect of combinations of unhealthy lifestyles on CAP and investigate the mediation role of metabolic disorder in this process. A total of 1299 adults were recruited from a hospital in Jiangsu, China, including 811 cases and 488 adults without diseases. The information on demographic characteristics and lifestyles was collected through questionnaires and the medical record system. Serum biochemical parameters were determined using the automatic biochemical analyzer. Adjusted regression analysis showed that unhealthy lifestyles, including smoking, overnight meals, daily water intake, staying up late, and exercise associated with the risk of CAP. Furthermore, metabolic biomarkers, including BMI, triglycerides, and uric acid, were associated with the risk of CAP. Also, unhealthy lifestyle scores were positively associated with BMI, triglycerides, and CAP. The mediation effect of metabolic biomarkers, such as BMI and triglycerides on the association of unhealthy lifestyle scores with CAP was significant. Available data demonstrate the adverse effect of combinations of unhealthy lifestyle factors on CAP, and metabolic disorders to potentially mediate the association of unhealthy lifestyles with the risk of CAP.

Characteristics and risk factors for colorectal polyps among children in an urban area of Wenzhou, China: a retrospective case control study

BACKGROUND

Scarce evidence exists on pediatric colorectal polyp risk factors. This study explored the clinical manifestations, morphological and pathological characteristics of, and risk factors for pediatric colorectal polyps.

METHODS

This retrospective case-control study included children who received colonoscopy, divided into a colorectal polyp group and a normal control group based on colonoscopy results. The risk factors for colorectal polyps in children were analyzed through logistic regression analysis.

RESULTS

The mean age of children with polyps was 6.77 ± 3.44 years. Polyps were detected predominantly in males (72.9%); hematochezia was the primary clinical manifestation (80.25%). Most polyps were juvenile (88.9%) and solitary (87.7%); 50.6% were located in the rectosigmoid area. Univariate analysis showed that gender (P = 0.037), age (P < 0.001), family aggregation (P < 0.001), specific immunoglobulin E (sIgE) (P < 0.001), platelet count (P = 0.001), aspartate aminotransferase (AST) (P = 0.016), meat intake (P = 0.010), and vegetable intake (P < 0.001) were significantly associated with colorectal polyps. Age ≤ 6 years (3-6 years: OR: 26.601, 95% CI: 3.761-160.910; < 3 years: OR: 22.678, 95% CI: 1.873-274.535), positive family aggregation (OR: 3.540, 95% CI: 1.177-10.643), positive sIgE (OR:2.263, 95% CI: 1.076-4.761), and higher meat intake (OR:1.046, 95% CI: 1.029-1.063) were risk factors for pediatric colorectal polyps in logistic regression analysis. Higher vegetable intake (OR: 0.993, 95% CI: 0.986-1.000) was a protective factor against pediatric colorectal polyps. The area under the curve (AUC) of meat intake in the receiver operating characteristic (ROC) curve analysis for predicting colorectal polyps was 0.607; the best cut-off value was 92.14 g/d (P = 0.010, 95% CI: 0.527-0.687). The meat and vegetable intake combination AUC in predicting pediatric colorectal polyps was 0.781 (P < 0.001, 95% CI: 0.718-0.845).

CONCLUSIONS

Juvenile, solitary, and located in the rectosigmoid region polyps are most common in children. Hematochezia is the main clinical manifestation. Most polyps were, but multiple and proximally located polyps were also detected. Age ≤ 6 years, especially 3-6 years, positive family aggregation, positive sIgE, and higher meat intake are risk factors for pediatric colorectal polyps. A higher vegetable intake is a protective factor.

Independent and joint associations of general and abdominal obesity with the risk of conventional adenomas and serrated polyps: A large population-based study in East Asia

Evidence regarding associations of general and abdominal obesity with the risk of conventional adenomas (ADs) and serrated polyps (SPs) from Asian population is scarce. Our study aimed to investigate the independent and joint associations of general obesity assessed by body mass index (BMI) and abdominal obesity assessed by waist circumference (WC) or waist-to-hip ratio (WHR) with the risk of ADs and SPs among 25 222 participants recruited by a population-based screening program. Compared to participants with normal BMI, those with a BMI ≥28 kg/m2 had increased risk of ADs (odds ratio [OR] 1.52, 95% confidence interval [CI]: 1.36-1.70) and SPs (OR 1.69, 95% CI: 1.38-2.07). For participants with a WC ≥102 cm (≥88 cm for females), the risk of ADs (OR 1.37, 95% CI: 1.25-1.51) and SPs (OR 1.81, 95% CI: 1.52-2.16) was higher than that of the reference group. For participants with a WHR ≥0.95 (≥0.90 for females), the risk of ADs (OR 1.26, 95% CI: 1.16-1.36) and SPs (OR 1.46, 95% CI: 1.26-1.69) was higher than that of the reference group. Moreover, participants with both BMI ≥28 kg/m2 and WC ≥102 cm (≥88 cm for females) had 61% and 119% higher risk of ADs (OR 1.61, 95% CI: 1.39-1.85) and SPs (OR 2.19, 95% CI: 1.70-2.82) compared to those with both normal BMI and WC. These findings indicate that both general and abdominal obesity are associated with SPs and ADs, presenting stronger association with SPs than ADs. Moreover, the association is more evident when both obesities exist.

Validity of pathological diagnosis for early colorectal cancer in genetic background

BACKGROUND

This study aimed to investigate the validity of pathological diagnosis of early CRC (E-CRC) from the genetic background by comparing data of E-CRC to colorectal adenoma (CRA) and The Cancer Genome Atlas (TCGA) on advanced CRC (AD-CRC).

METHODS

TCGA data on AD-CRC were studied in silico, whereas by next-generation sequencer, DNA target sequences were performed for endoscopically obtained CRA and E-CRC samples. Immunohistochemical staining of mismatch repair genes and methylation of MLH1 was also performed. The presence of oncogenic mutation according to OncoKB for the genes of the Wnt, MAPK, and cell-cycle-signaling pathways was compared among CRA, E-CRC, and AD-CRC.

RESULTS

The study included 22 CRA and 30 E-CRC lesions from the Chiba University Hospital and 212 AD-CRC lesions from TCGA data. Regarding the number of lesions with driver mutations in the Wnt and cell-cycle-signaling pathways, E-CRC was comparable to AD-CRC, but was significantly greater than CRA. CRA had significantly more lesions with a driver mutation for the Wnt signaling pathway only, versus E-CRC.

CONCLUSIONS

In conclusion, the definition of E-CRC according to the Japanese criteria had a different genetic profile from CRA and was more similar to AD-CRC. Based on the main pathway, it seemed reasonable to classify E-CRC as adenocarcinoma. The pathological diagnosis of E-CRC according to Japanese definition seemed to be valid from a genetic point of view.

Genetic Signatures of Glucose Homeostasis: Synergistic Interplay With Long-Term Exposure to Cigarette Smoking in Development of Primary Colorectal Cancer Among African American Women

INTRODUCTION

Insulin resistance (IR)/glucose intolerance is a critical biologic mechanism for the development of colorectal cancer (CRC) in postmenopausal women. Whereas IR and excessive adiposity are more prevalent in African American (AA) women than in White women, AA women are underrepresented in genome-wide studies for systemic regulation of IR and the association with CRC risk.

METHODS

With 780 genome-wide IR single-nucleotide polymorphisms (SNPs) among 4,692 AA women, we tested for a causal inference between genetically elevated IR and CRC risk. Furthermore, by incorporating CRC-associated lifestyle factors, we established a prediction model on the basis of gene-environment interactions to generate risk profiles for CRC with the most influential genetic and lifestyle factors.

RESUTLS

In the pooled Mendelian randomization analysis, the genetically elevated IR was associated with 9 times increased risk of CRC, but with lack of analytic power. By addressing the variation of individual SNPs in CRC in the prediction model, we detected 4 fasting glucose-specific SNPs in GCK, PCSK1, and MTNR1B and 4 lifestyles, including smoking, aging, prolonged lifetime exposure to endogenous estrogen, and high fat intake, as the most predictive markers of CRC risk. Our joint test for those risk genotypes and lifestyles with smoking revealed the synergistically increased CRC risk, more substantially in women with longer-term exposure to cigarette smoking.

DISCUSSION

Our findings may improve CRC prediction ability among medically underrepresented AA women and highlight genetically informed preventive interventions (e.g., smoking cessation; CRC screening to longer-term smokers) for those women at high risk with risk genotypes and behavioral patterns.

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.

Prognostic Value of Preoperative Fibrinogen for Predicting Clinical Outcome in Patients with Nonmetastatic Colorectal Cancer

Background

The prognostic role of preoperative fibrinogen in colorectal cancer (CRC) patients remains controversial. Therefore, we assessed the predictive value of preoperative fibrinogen and developed a tool for predicting the survival of CRC patients.

Methods

This retrospective study evaluated 1869 patients who underwent curative resection for CRC. Univariate and multivariate survival analyses were conducted to identify the factors correlated with overall survival (OS) and cancer-specific survival (CSS). Nomograms were developed as a graphical representation of the Cox proportional hazards regression models. The performance of the nomograms was assessed by Harrell’s concordance index (c-index) and calibration plots.

Results

The preoperative fibrinogen levels were correlated with age, tumor differentiation, tumor location, pT category, and TNM stage. In the multivariate analysis, elevated fibrinogen level was independently correlated with worse OS and CSS (OS: hazard ratio [HR] = 0.777, 95% confidence interval [95% CI] = 0.630–0.958, P = 0.018; CSS: HR = 0.757, 95% CI = 0.605–0.947, P = 0.015). The nomograms could predict outcomes with a c-index for OS and CSS of 0.79 and 0.81, respectively. The nomograms also had a good calibration.

Conclusion

Preoperative fibrinogen level was an independent marker of poor prognosis in patients with nonmetastatic CRC, and there was a threshold level for the use of fibrinogen as a prognostic factor. Furthermore, nomograms may help predict the individual risk of OS and CSS in patients treated for CRC.

Efficacy, safety, and tolerability of a ready-to-drink bowel preparation in overweight and obese adults: subanalysis by body mass index from a phase III, assessor-blinded study

BACKGROUND

We performed a post hoc secondary analysis for the effect of body mass index (BMI) on the efficacy, tolerability, and safety of ready-to-drink sodium picosulfate, magnesium oxide, and citric acid (SPMC oral solution) bowel preparation.

METHODS

A phase III, randomized, assessor-blinded, multicenter, noninferiority study was conducted comparing split-dose, low-volume SPMC oral solution with a powder formulation for oral solution. A post hoc secondary analysis assessed efficacy, safety, and tolerability of SPMC oral solution stratified by BMI. BMI was classified by Centers for Disease Control and Prevention definitions (underweight and normal weight: BMI < 25 kg/m²; overweight: BMI 25-29.9 kg/m²; class I obesity: BMI 30-34.9 kg/m²; class II obesity: BMI 35-39.9 kg/m²; class III/severe obesity: BMI ⩾40 kg/m²). Prespecified primary efficacy endpoint ('responders') was the proportion of participants with 'excellent' or 'good' ratings on a modified Aronchick Scale (AS). Secondary efficacy outcomes were the quality of cleansing of the right colon as assessed by the Boston Bowel Preparation Scale (BBPS); as well as selected findings from the Mayo Clinic Bowel Prep Tolerability Questionnaire. Safety assessments included adverse events (AEs) and laboratory evaluations.

RESULTS

Between 82.8% and 92.5% of participants in any BMI group were responders by AS, and between 91.3% and 100% were responders by BBPS in the right colon. Efficacy was consistent across BMI groups, with no clear trends. Greater than 83% of participants in any BMI group found the preparation 'easy' or 'acceptable' to ingest, and the majority (>58%) rated SPMC oral solution as 'better' than a prior bowel preparation. In all BMI groups, safety data were similar to the overall cohort. Commonly reported, drug-related, treatment-emergent AEs were, by ascending BMI group, nausea (1.1%, 5.3%, 1.0%, 5.7%, and 0%) and headache (1.1%, 4.1%, 1.0%, 5.7%, and 0%).

CONCLUSIONS

Ready-to-drink SPMC oral solution had consistent, good quality colon cleansing, and favorable tolerability among participants of all BMI groups.

CLINICALTRIALSGOV REGISTRATION

NCT03017235.

The impact of body weight on dysplasia of colonic adenomas: a case-control study

OBJECTIVE

Colorectal cancer (CRC) is common across countries in males and females. Most cases originate from adenomas harboring high grade dysplasia. Among risk factors, weight excess has been suggested to positively influence dysplasia progression. In this study, the relationship between dysplasia grade of adenomas and body mass index (BMI) categories was analyzed.

METHODS

This was a retrospective case-control study. A total of 4745 charts (59.8% females) from patients undergoing colonoscopy were collected. Data regarding age, sex, smoking habits, occupation, residence, personal history of CRC, personal history of polyps and BMI were retrieved. Adenomas with high-grade dysplasia were labeled as advanced.

RESULTS

They were 970 (20.4%) subjects with adenomas (cases: mean age 64.67 ± 11.35 years) and 3775 without (controls: mean age 56.43 ± 16.56 years). As expected, adenomas were significantly associated with overweight or obesity. After adjusting for all covariates the presence of advanced adenoma was significantly associated with age, male sex, smoking habits, personal history of CRC, overweight (OR = 1.298, IC 95% 1.092-1.697) and obesity (OR = 1.780, IC 95% 1.260-2.515).

CONCLUSIONS

Our findings support the protective effect a normal weight against advanced adenomas. Reduction of BMI value should be pursued in healthy programs.

Obesity, diabetes and the risk of colorectal adenoma and cancer

BACKGROUND

Colorectal cancer (CRC) is the fourth most commonly diagnosed gastrointestinal (GI) malignancy and the third leading cause of cancer-related death worldwide. In the current case-control study, an association between diagnosis of CRC, obesity and diabetes was investigated.

METHODS

Demographic characteristics, colonoscopy reports, history of drug, smoking, and medical history were collected from patients referred to a colonoscopy unit. The location, size and number of the polyps were recorded during the colonoscopy. Statistically, t-test was conducted for mean comparison for the groups. Pearson's chi-squared test (χ2) was applied to categorize variables. Five classification methods based on the important clinicopathological characteristics such as age, BMI, diabetes, family history of colon cancer was performed to predict the results of colonoscopy.

RESULTS

Overall, 693 patients participated in this study. In the present study, 115 and 515 patients were evaluated for adenoma/adenocarcinoma and normal colonoscopy, respectively. The mean age of patients positive for adenoma or adenocarcinoma were significantly higher than the negative groups (p value < 0.001). Incidence of overweight and/or obesity (BMI > 25 kg/m2) were significantly higher in adenoma positive patients as compared to controls (49.9 and 0.9% respectively, p value = 0.04). The results also demonstrated a significant association between suffering from diabetes and having colon adenoma (OR = 1.831, 95%CI = 1.058-3.169, p value = 0.023). The experimental results of 5 classification methods on higher risk factors between colon adenoma and normal colonoscopy data were more than 82% and less than 0.42 for the percentage of classification accuracy and root mean squared error, respectively.

CONCLUSIONS

In the current study, the occurrence of obesity measured based on BMI and diabetes in the adenoma positive patient group was significantly higher than the control group although there was no notable association between obesity, diabetes and adenocarcinoma.

Increased Frequency of KRAS Mutations in African Americans Compared with Caucasians in Sporadic Colorectal Cancer

Objectives:

The basis for over-representation of colorectal cancer (CRC) in African-American (AA) populations compared with Caucasians are multifactorial and complex. Understanding the mechanisms for this racial disparity is critical for delivery of better care. Several studies have investigated sporadic CRC for differences in somatic mutations between AAs and Caucasians, but owing to small study sizes and conflicting results to date, no definitive conclusions have been reached.

Methods:

Here, we present the first systematic literature review and meta-analysis investigating the mutational differences in sporadic CRC between AAs and Caucasians focused on frequent driver mutations (APC,TP53, KRAS,PI3CA, FBXW7,SMAD4, and BRAF). Publication inclusion criteria comprised sporadic CRC, human subjects, English language, information on ethnicity (AA, Caucasian, or both), total subject number >20, and information on mutation frequencies.

Results:

We identified 6,234 publications. Meta-analysis for APC, TP54, FBXW7, or SMAD4 was not possible owing to paucity of data. KRAS mutations were statistically less frequent in non-Hispanic Whites when compared with AAs (odds ratio, 0.640; 95% confidence interval (CI): 0.5342–0.7666; P=0.0001), while the mutational differences observed in BRAF and PI3CA did not reach statistical significance.

Conclusions:

Here, we report the mutational patterns for KRAS, BRAF, and PI3CA in sporadic CRC of AAs and Caucasians in a systematic meta-analysis of previously published data. We identified an increase in KRAS mutations in sporadic CRC in AAs, which may contribute to worse prognosis and increased mortality of CRC in AAs. Future studies investigating health-care disparities in CRC in AAs should control for KRAS mutational frequency.

DNA base excision repair genetic risk scores, oxidative balance, and incident, sporadic colorectal adenoma

Associations of individual base excision repair (BER) genotypes with colorectal adenoma risk are unclear, but likely modest. However, genetic risk scores (GRS) that aggregate information from multiple genetic variants might be useful for assessing genetic predisposition to colorectal adenoma. We analyzed data pooled from three colonoscopy-based case-control studies of incident, sporadic colorectal adenoma (n = 488 cases, 604 controls) that collected blood for genotyping and extensive dietary and other data. We randomly split our population sample into training samples (half of the participants) and validation samples (the remaining participants) 10 times. Associations of 65 individual single nucleotide polymorphisms (SNPs) in 15 BER genes were assessed in the training samples and used to combine information from multiple risk variants into a BER GRS among the validation samples using unweighted and weighted methods. We also combined 15 extrinsic exposures with known pro- or antioxidant properties into an oxidative balance score (OBS). Associations of the BER GRS with colorectal adenoma, overall and jointly with the OBS, were assessed using multivariable logistic regression. The odds ratio for those in the highest relative to the lowest tertile of the weighted BER GRS was 2.07 (95% confidence interval, 1.26-3.40; p_trend  = 0.01). Relative to those with both a low GRS and a high (more antioxidant) OBS, the estimated direct association for those with both a high BER GRS and a low OBS was stronger than for those in other GRS/OBS categories. Our findings suggest that BER genotypes collectively may be associated with incident sporadic colorectal adenomas.

How significant is the association between metabolic syndrome and prevalence of colorectal neoplasia?

The incidence and prevalence of metabolic syndrome (MS) and colorectal cancer (CRC) has been rising in developed countries. The association between these two diseases has been widely studied and reported. Less evidence is available about the relationship between MS and CRC precancerous lesions (adenomatous polyps, adenomas). The aim of this paper is to present an overview of our scientific understanding of that topic and its implication in clinical practice. One of the principal goals of current CRC secondary prevention efforts is to detect and remove the precancerous lesions in individuals with an average CRC risk to prevent the development of invasive cancer. MS is not currently considered a high-risk CRC factor and is therefore not included in the guidelines of organized screening programs. However, in light of growing scientific evidence, the approach to patients with MS should be changed. Metabolic risk factors for the development of adenomas and cancers are the same - obesity, impaired glucose tolerance, dyslipidemia, hypertension, cardiovascular diseases and diabetes mellitus type 2. Therefore, the key issue in the near future is the development of a simple scoring system, easy to use in clinical practice, which would identify individuals with high metabolic risk of colorectal neoplasia and would be used for individual CRC secondary prevention strategies. Currently, such scoring systems have been published based on Asian (Asia-Pacific Colorectal Screening Score; APCS) and Polish populations.

Increased Risk of Advanced Colorectal Neoplasia Among Korean Men With Metabolic Abnormality and Obesity

BACKGROUND & AIMS

Obesity and metabolic abnormality are risk factors for colorectal cancer and adenoma. We evaluated the risk of advanced colorectal neoplasm (AN) according to metabolic status and obesity in Koreans.

METHODS

We performed a retrospective cross-sectional study of 70,428 individuals in Korea who underwent colonoscopy and whose metabolic state and body mass index were examined, from 2003 through 2012, at Kangbuk Samsung Hospital in Korea. We calculated odds ratios (ORs) for AN in people who were metabolically healthy but obese, people with metabolic abnormality who were not obese, and people with metabolic abnormality who were obese. The reference group was metabolically healthy nonobese peoples. AN was defined as adenoma ≥10 mm in diameter, adenoma with any component of villous histology, high-grade dysplasia, or invasive cancer.

RESULTS

No increased risk of AN was observed in the metabolically healthy but obese (OR, 0.99; 95% confidence interval [CI], 0.67-1.46; P = .825) and metabolic abnormality who were not obese groups (OR, 1.01; 95% CI, 0.85-1.21; P = .765). In contrast, risk of AN was increased in the metabolic abnormality who were obese group (OR, 1.33; 95% CI, 1.12-1.58; P = .006). In men, risk of AN showed a greater increase in the metabolic abnormality who were obese group (OR, 1.48; 95% CI, 1.20-1.83; P = .001). This association was not observed in women (OR, 1.21; 95% CI, 0.84-1.75; P = .476).

CONCLUSIONS

Men with 1 or more metabolic abnormality and obesity are at increased risk for AN.

Increased MACC1 levels in tissues and blood identify colon adenoma patients at high risk

Background

Colorectal cancer is a preventable disease if caught at early stages. This disease is highly aggressive and has a higher incidence in African Americans. Several biomarkers and mutations of aggressive tumor behavior have been defined such as metastasis-associated in colon cancer 1 (MACC1) that was associated with metastasis in colorectal cancer patients. Here, we aim to assess colon tissue MACC1 protein and circulating MACC1 transcripts in colon preneoplastic and neoplastic African American patients.

Methods

Patients’ tissue samples (n = 143) have been arranged on three tissue microarrays for normal (n = 26), adenoma (n = 68) and cancer (n = 49) samples. Immunohistochemistry was used to detect MACC1 expression. Blood samples (n = 93) from normal (n = 45), hyperplastic (n = 15) and tubular adenoma (n = 33) patients were used to assess MACC1 transcripts using qRT-PCR. Distribution of continuous variables was tested between different diagnoses with Kruskal–Wallis test. Categorical variables were tested by Chi square test. We assessed the prognostic ability of IHC staining by calculating area under receiver operating characteristics curve (ROC) for adenoma and cancer separately. Differences between groups in terms of MACC1 transcript levels in plasma were calculated by using non-parametric (exact) Wilcoxon-Mann–Whitney tests. We performed all calculations with SPSS, version 21.

Results

In patient tissues, there was a statistically significant difference in MACC1 expression in normal vs. adenoma samples (p = 0.004) and normal vs. cancer samples (p < 0.001). There was however no major difference in MACC1 expression between adenoma vs. cancer cases or tubular adenomas vs tubulovillous adenomas. The area under the curve for both normal vs. adenoma and normal vs. cancer cases were 70 and 67 %, respectively. MACC1 expression was not correlated to age, gender or anatomical sample location. In patient plasma, MACC1 transcripts in adenoma patients were significantly higher than in plasma from normal patients (p = 0.014). However, the difference between normal and hyperplastic plasma MACC1 transcripts was not statistically significant.

Conclusion

Metastasis-associated in colon cancer 1 is expressed at early stages of colorectal oncogenesis within the affected colonic tissue in this patient cohort. The plasma transcripts can be used to stratify African American patients at risk for potential malignant colonic lesions.

Obesity and colorectal cancer: molecular features of adipose tissue

The huge part of population in developed countries is overweight or obese. Obesity is often determined by body mass index (BMI) but new accurate methods and ratios have recently appeared to measure body fat or fat located in the intestines. Early diagnosis of obesity is crucial since it is considered an increasing colorectal cancer risk factor. On the one hand, colorectal cancer has been strongly associated with lifestyle factors. A diet rich in red and processed meats may increase colorectal cancer risk; however, high-fiber diets (grains, cereals and fruits) have been associated with a decreased risk of colorectal cancer. Other life-style factors associated with obesity that also increase colorectal cancer risk are physical inactivity, smoking and high alcohol intake. Cutting-edge studies reported that high-risk transformation ability of adipose tissue is due to production of different pro-inflammatory cytokines like IL-8, IL-6 or IL-2 and other enzymes like lactate dehydrogenase (LDH) and tumour necrosis factor alpha (TNFα). Furthermore, oxidative stress produces fatty-acid peroxidation whose metabolites possess very high toxicities and mutagenic properties. 4-hydroxy-2-nonenal (4-HNE) is an active compounds that upregulates prostaglandin E2 which is directly associated with high proliferative colorectal cancer. Moreover, 4-HNE deregulates cell proliferation, cell survival, differentiation, autophagy, senescence, apoptosis and necrosis via mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PIK3CA)—AKT and protein kinase C pathways. Other product of lipid peroxidation is malondialdehyde (MDA) being able to regulate insulin through WNT-pathway as well as having demonstrated its mutagenic capability. Accumulation of point mutation enables genomic evolution of colorectal cancer described in the model of Fearon and Vogelstein. In this review, we will summarize different determination methods and techniques to assess a truthfully diagnosis and we will explain some of the capabilities that performs adipocytes as the largest endocrine organ.

Genetic Basis for Colorectal Cancer Disparities

African Americans suffer the highest burden from colorectal cancer (CRC) in the USA. Studies have suggested that healthcare access and poorer utilization of preventive services may be playing more of a role in this disparity. However, African Americans also tend to develop CRC at younger ages and are more likely to have proximal cancers. This raises the possibility of higher genetic predisposition to CRC among African Americans and this has not been well studied. In this article, we reviewed possible genetic basis underpinning biological differences in CRC burden in the USA.

Increased risk of colorectal polyps in patients with non-alcoholic fatty liver disease undergoing liver transplant evaluation

BACKGROUND

Screening colonoscopy is a standard part of the liver transplant (LT) evaluation process. We aimed to evaluate the yield of screening colonoscopy and determine whether non-alcoholic fatty liver disease (NAFLD) was associated with an increased risk of colorectal neoplasia.

METHODS

We retrospectively assessed all patients who completed LT evaluation at our center between 1/2008-12/2012. Patients <50 years old and those without records of screening colonoscopy, or with greater than average colon cancer risk were excluded.

RESULTS

A total of 1,102 patients were evaluated, 591 met inclusion criteria and were analyzed. The mean age was 60 years, 67% were male, 12% had NAFLD and 88% had other forms of chronic liver disease. Overall, 42% of patients had a polyp found on colonoscopy: 23% with adenomas, 14% with hyperplastic polyps and with 1% inflammatory polyps. In the final multivariable model controlling for age, NAFLD [odds ratio (OR) 2.41, P=0.001] and a history of significant alcohol use (OR 1.69, P=0.004) were predictive of finding a polyp on colonoscopy. In addition, NAFLD (OR 1.95, P=0.02), significant alcohol use (OR 1.70, P=0.01) and CTP class C (OR 0.57, P=0.02) were associated with adenoma, controlling for age.

CONCLUSIONS

Screening colonoscopy in patients awaiting LT yields a high rate of polyp (43%) and adenoma (22%) detection, perhaps preventing the accelerated progression to carcinoma that can occur in immunosuppressed post-LT patients. Patients with NAFLD may be at a ~2 fold higher risk of adenomas and should be carefully evaluated prior to LT.

Mechanisms by Which Pleiotropic Amphiphilic n-3 PUFA Reduce Colon Cancer Risk

Colorectal cancer is one of the major causes of cancer-related mortality in both men and women worldwide. Genetic susceptibility and diet are primary determinants of cancer risk and tumor behavior. Experimental, epidemiological, and clinical data substantiate the beneficial role of n-3 polyunsaturated fatty acids (PUFA) in preventing chronic inflammation and colon cancer. From a mechanistic perspective, n-3 PUFA are pleiotropic and multifaceted with respect to their molecular mechanisms of action. For example, this class of dietary lipid uniquely alters membrane structure/ cytoskeletal function, impacting membrane receptor function and downstream signaling cascades, including gene expression profiles and cell phenotype. In addition, n-3 PUFA can synergize with other potential anti-tumor agents, such as fermentable fiber and curcumin. With the rising prevalence of diet-induced obesity, there is also an urgent need to elucidate the link between chronic inflammation in adipose tissue and colon cancer risk in obesity. In this review, we will summarize recent developments linking n-3 PUFA intake, membrane alterations, epigenetic modulation, and effects on obesity-associated colon cancer risk.