Prospective investigation of body mass index, colorectal adenoma, and colorectal cancer in the prostate, lung, colorectal, and ovarian cancer screening trial

Barriers to the use of tests for early detection of colorectal cancer in Chile

This study aimed to assess the use of colorectal cancer (CRC) tests for prevention and early detection, alongside exploring the associated barriers to these tests. A stratified national survey was conducted in Chile, involving 1893 respondents (with a 2.3% error margin and 95% confidence interval). Logistic and multinomial regression analyses were employed to examine variations in test utilization likelihood and barrier. We found that the key determinants for undergoing CRC tests included age, health status, possession of private health insurance, and attainment of postgraduate education. Notably, 18% and 29% of respondents covered by public and private insurance, respectively, cited personal prevention as the primary motivation for test uptake. The principal obstacle identified was lack of knowledge, mentioned by 65% of respondents, while 29% and 19% of the publicly and privately insured respectively highlighted lack of access as a barrier. The results of this study provide valuable insights into factors influencing CRC screening, aiming to inform public health policies for expanding national coverage beyond diagnosis and treatment to encompass preventive measures.

Adenoma Detection Rate and Clinical Characteristics Influence Advanced Neoplasia Risk After Colorectal Polypectomy

BACKGROUND AND AIMS

Postpolypectomy risk stratification for subsequent metachronous advanced neoplasia (MAN) is imprecise and does not account for colonoscopist adenoma detection rate (ADR). Our aim was to assess association of ADR with MAN and create a prediction model for postpolypectomy risk stratification incorporating ADR and other factors.

METHODS

We conducted a retrospective cohort study of individuals with baseline polypectomy and subsequent surveillance colonoscopy from 2004 to 2016 within the U.S. Department of Veterans Affairs (VA). Clinical factors, polyp findings, and baseline colonoscopist ADR were considered for the model. Model performance (sensitivity, specificity, and area under the curve) for identifying individuals with MAN was compared with 2020 U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) surveillance recommendations.

RESULTS

A total of 30,897 individuals were randomly assigned 2:1 into independent model training and validation sets. Increasing age, male sex, diabetes, current smoking, adenoma number, polyp location, adenoma ≥10 mm or with tubulovillous/villous features, and decreasing colonoscopist ADR were independently associated with MAN. A range of 1.48- to 1.66-fold increased risk for MAN was observed for ADR in the lowest 3 quintiles (ADR <19.7%-39.3%) vs the highest quintile (ADR >47.0%). When the final model selected based on the training set was applied to the validation set, improved sensitivity and specificity over 2020 USMSTF risk stratification were achieved (P = .001), with an area under the curve of 0.62 (95% confidence interval, 0.60-0.64).

CONCLUSIONS

Colonoscopist ADR is associated with MAN. Combining clinical factors and ADR for risk stratification has potential to improve postpolypectomy risk stratification. Improving ADR is likely to improve postpolypectomy outcomes.

Adipocyte-Derived Exosomal MTTP Suppresses Ferroptosis and Promotes Chemoresistance in Colorectal Cancer

Obesity is closely related to a poor prognosis in patients with advanced colorectal cancer (CRC), but the mechanisms remain unclear. Ferroptosis is a form of nonapoptotic cell death characterized by lipid reactive oxygen species (ROS) accumulation and iron dependency and is associated with the chemoresistance of tumors. Here, it is shown that adipose-derived exosomes reduce ferroptosis susceptibility in CRC, thus promoting chemoresistance to oxaliplatin. It is found that microsomal triglyceride transfer protein (MTTP) expression is increased in the plasma exosomes of CRC patients with a high body fat ratio, serving as an inhibitor of ferroptosis and reducing sensitivity to chemotherapy. Mechanistically, the MTTP/proline-rich acidic protein 1 (PRAP1) complex inhibited zinc finger E-box binding homeobox 1 expression and upregulated glutathione peroxidase 4 and xCT, leading to a decreased polyunsaturated fatty acids ratio and lipid ROS levels. Moreover, experiments are carried out in organoids, and a tumor implantation model is established in obese mice, demonstrating that the inhibition of MTTP increases the sensitivity to chemotherapy. The results reveal a novel intracellular signaling pathway mediated by adipose-derived exosomes and suggest that treatments targeting secreted MTTP might reverse oxaliplatin resistance in CRC.

Role of EphB2/ephrin‑B1 signalling in the development and progression of obesity‑associated colorectal cancer

Obesity is a major problem worldwide and has been associated with colorectal cancer development, among other diseases. Ephrin receptors and ligands play an important role in the turnover of the intestinal mucosa and intestinal crypt compartmentalization. It has been hypothesised that obesity-induced inflammation affects ephrin signals, leading to carcinogenesis. Therefore, the aim of the present study was to assess the relationship between Eph-ephrin B signalling, obesity and obesity-associated colorectal cancer. An azoxymethane-induced obesity-associated cancer KKAy mouse model developed in our prior study was used. A total of 46 patients with consecutive colorectal cancer and 48 tumours were analysed. Immunohistological analyses were performed in mouse and human samples, and immunoreactive scores (IRS) were determined. KKAy mice were significantly more prone to cancer development compared with control C57/BL mice (2/15 in C57/BL vs. 10/10 in KKAy; P<0.001). TUNEL assay revealed a lower number of apoptotic cells in normal mucosa of KKAy mice (8.8% in C57/BL vs. 3.2% in KKAy; P<0.001) and obese patients (9.2% with BMI <25 vs. 3.6% with BMI ≥25; P=0.021). Immunohistological analysis revealed that ephrin-B1 was downregulated in normal mucosa from KKAy mice and obese patients (IRS, 2.86 with BMI <25 vs. 6.00 with BMI ≥25; P=0.002). Moreover, EphB2 was downregulated in tumours from KKAy mice and obese patients (IRS, 6.58 with BMI <25 vs. 3.83 with BMI ≥25; P<0.001). The distribution of infiltrated macrophages corresponded to the MCP-1 expression pattern in KKAy mice, and the number of macrophages was also significantly higher in those mice (36.3 in C57/BL vs. 120.0 in KKAy; P=0.029). The findings suggested that obesity results in disruption of EphB2/ephrin-B1 signalling, promoting colorectal cancer development and progression.

Inflammatory potential of diet and colorectal carcinogenesis: a prospective longitudinal cohort

BACKGROUND

Acknowledging the role of inflammation in colorectal carcinogenesis, this study aimed to evaluate the associations between diet-associated inflammation, as measured by the energy-adjusted dietary inflammatory index (E-DIITM), and distinct stages of colorectal carcinogenesis.

METHODS

The Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial enrolled participants without a colorectal cancer history, who were asked to complete baseline questionnaires and food frequency questionnaires. To estimate the associations between the E-DII and risks of newly incident colorectal adenoma, recurrent adenoma, and colorectal cancer, multivariable-adjusted Cox proportional hazards regression models were employed.

RESULTS

Among 101,680 participants, with an average age of 65 years, a total of 1177 incident colorectal adenoma cases, 895 recurrent adenoma cases and 1100 colorectal cancer cases were identified. Higher E-DII scores from food and supplement (HRQ5 vs Q1: 0.86 [0.69-1.06], Ptrend: 0.27) or from food only (HRQ5 vs Q1: 0.82 [0.64-1.05], Ptrend: 0.06) were not associated with higher risks of incident adenoma. However, the elevated risk of recurrent adenoma was found in the highest category of E-DII from food plus supplement (HRQ5 vs Q1: 1.63 [1.28-2.03], Ptrend: < 0.001) when compared with the lowest category. A significant association between colorectal cancer risk and E-DII from food plus supplement (HRQ5 vs Q1: 1.34 [1.09-1.65], Ptrend: 0.009) was found, where this association was only pronounced in distal colorectal cancer.

CONCLUSION

Higher E-DII scores from diet plus supplement but not from diet only were associated with a higher risk of recurrent adenoma and distal colorectal cancer. The role of nutrient supplements on cancer risk, especially when combined with diet, needs to be elucidated in future studies.

OUP accepted manuscript

Background

Although obesity is a known risk factor, the impact of weight change on colorectal adenoma risk is less clear and could have important implications in disease prevention. We prospectively evaluated weight change in adulthood and incident colorectal adenoma.

Methods

We assessed weight change during early-late (age 20 years to baseline, ie, ages 55-74 years), early-middle (20-50 years), and middle-late (50 years-baseline) adulthood using self-reported weight data in relation to incident distal adenoma in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (cases = 1053; controls = 16 576). For each period, we defined stable weight as greater than −0.5 kg to less than or equal to 1 kg/5 years, weight loss as less than or equal to −0.5 kg/5 years, and weight gain as greater than 1-2, greater than 2-3, or greater than 3 kg/5 years. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) using logistic regression; all tests were 2-sided.

Results

Compared with stable weight, weight loss during early-late adulthood was associated with reduced adenoma risk (OR = 0.54, 95% CI = 0.34 to 0.86), particularly among those who were overweight or obese at age 20 years (OR = 0.39, 95% CI = 0.18 to 0.84). Results were similar for early-middle adulthood but less pronounced for middle-late adulthood. Weight gain greater than 3 kg/5 years during early-late adulthood was associated with increased risk (OR = 1.30, 95% CI = 1.07 to 1.58, P_trend < .001). Findings appeared stronger among men (OR for >3 kg/5 years = 1.41, 95% CI = 1.11 to 1.80) than women (OR = 1.09, 95% CI = 0.79 to 1.50, P_interaction = .21).

Conclusions

Weight loss in adulthood was associated with reduced adenoma risk, particularly for those who were overweight or obese, whereas weight gain greater than 3 kg/5 years increased risk. Findings underscore the importance of healthy weight maintenance throughout adulthood in preventing colorectal adenoma.

Derivation and Clinical Validation of a Redox-Driven Prognostic Signature for Colorectal Cancer

Colorectal cancer (CRC), a seriously threat that endangers public health, has a striking tendency to relapse and metastasize. Redox-related signaling pathways have recently been extensively studied in cancers. However, the study and potential role of redox in CRC remain unelucidated. We developed and validated a risk model for prognosis and recurrence prediction in CRC patients via identifying gene signatures driven by redox-related signaling pathways. The redox-driven prognostic signature (RDPS) was demonstrated to be an independent risk factor for patient survival (including OS and RFS) in four public cohorts and one clinical in-house cohort. Additionally, there was an intimate association between the risk score and tumor immune infiltration, with higher risk score accompanied with less immune cell infiltration. In this study, we used redox-related factors as an entry point, which may provide a broader perspective for prognosis prediction in CRC and have the potential to provide more promising evidence for immunotherapy.

Genome-wide association study of colorectal polyps identified highly overlapping polygenic architecture with colorectal cancer

No genome-wide association studies (GWAS) were reported for colorectal polyps and the overlap in polygenic backgrounds conferring risk of colorectal cancer and polyps remains unclear. We performed GWAS on subjects with colorectal polyps using the BioBank Japan data with 4447 cases and 157,226 controls. We evaluated genetic correlations between colorectal polyps and cancer, and effects on colorectal polyps of single nucleotide polymorphisms (SNPs) known to be associated with colorectal cancer. We identified CUX2, a known genetic locus to colorectal cancer, as a susceptibility locus to colorectal polyps (p value = 1.1 × 10^-15). Subsequent fine-mapping analysis indicated that rs11065828 in CUX2 is the causal variant for colorectal polyps. We found that known colorectal cancer-susceptible SNPs were also associated with colorectal polyps. The genetic correlation between colorectal cancer and polyps is very high (r = 0.98 and p value = 0.0006). We additionally identified 14 significant loci of colorectal polyps and three significant loci of colorectal cancer by applying the multi-trait analysis of GWAS of colorectal cancer and colorectal polyps. We showed very similar germline polygenic features, which gives us the additional insight into potential cancers at polygenic levels for patients with polyps who are followed up at outpatients' clinic; thus, close observation and polypectomy is critical to prevent colorectal cancers.

Aspirin, ibuprofen, and reduced risk of advanced colorectal adenoma incidence and recurrence and colorectal cancer in the PLCO Cancer Screening Trial

BACKGROUND

Studying the differential impact of aspirin and other nonsteroidal anti-inflammatory drugs across the stages of colorectal neoplasia from early adenoma to cancer is critical for understanding the benefits of these widely used drugs.

METHODS

With 13 years of follow-up, the authors prospectively evaluated the association between aspirin and ibuprofen use and incident distal adenoma (1221 cases), recurrent adenoma (862 cases), and incident colorectal cancer (CRC; 2826 cases) among men and women in the population-based Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. With multivariable-adjusted models, odds ratio (ORs) and 95% confidence intervals (CIs) for adenoma incidence and recurrence and hazard ratios (HRs) and 95% CIs for incident CRC were determined.

RESULTS

The authors observed a significantly reduced risk of incident adenoma with ibuprofen use (≥30 vs <4 pills per month: OR, 0.76 [95% CI, 0.60-0.95]; Ptrend = .04), particularly advanced adenoma (OR, 0.48 [95% CI, 0.28-0.83]; Ptrend = .005). Among those with a previous adenoma detected through screening, aspirin use was associated with a decreased risk of advanced recurrent adenoma (≥30 vs <4 pills per month: OR, 0.56 [95% CI, 0.36-0.87]; Ptrend = 0.006). Both aspirin (HR, 0.88 [95% CI, 0.81-0.96]; Ptrend <.0001) and ibuprofen use (HR, 0.81 [95% CI, 0.70-0.93); Ptrend = 0.003) ≥30 versus <4 pills per month were significantly associated with reduced CRC risk.

CONCLUSIONS

In this large prospective study with long-term follow-up, a beneficial role for not only aspirin, but also ibuprofen, in preventing advanced adenoma and curbing progression to recurrence and cancer among older adults was observed.

Penicillin disrupts mitochondrial function and induces autophagy in colorectal cancer cell lines

Colorectal cancer is a common malignant tumor of the gastrointestinal tract. Currently, the main treatment is surgical resection, which can be combined with other treatments. However, treatment efficacy is poor, and colorectal cancer is prone to relapse and metastasis; thus, identifying an effective anti-cancer drug is an urgent requirement. The present study examined the antagonistic effect of penicillin on cultured colorectal cancer cells and the related mechanism. A MTT assay was used to assess the growth of the colorectal cancer cells treated with penicillin and to determine the optimal drug concentration. The wound healing and Transwell invasion assays were performed to investigate the effect of penicillin on the migration and invasion of the colorectal cancer cells. Live cell mitochondrial energy metabolism analysis was performed to detect changes in mitochondrial energy metabolism of the colorectal cancer cells, while western blot analysis was used to measure the expression of cytochrome c and autophagy-related protein, LC3. RFP-GFP-LC3 lentivirus was used to detect autophagic flux, and autophagosomes were observed using a transmission electron microscope, while flow cytometry was used to analyze the effect of penicillin on cell cycle progression and apoptosis of the colorectal cancer cells. After penicillin treatment, the growth, migration and invasion ability of the colorectal cancer cells were inhibited. The mitochondrial energy metabolism of the cell was impaired, and the basic respiratory capacity, maximum respiratory capacity, respiratory potential, and ATP production were all reduced. The protein expression levels of the autophagy-related proteins, LC3-II/LC3-I increased in a dose- and time-dependent manner. In addition, autophagy flux and the number of autophagosomes increased, and mitochondrial structural damage was observed. The cell cycle was arrested at the G₁ phase, the number of early apoptotic cells increased and the protein expression level of cleaved caspase-3 increased, while penicillin-induced apoptosis was blocked by the autophagy inhibitor 3-MA. In conclusion, penicillin disrupted mitochondrial function and energy metabolism in the colorectal cancer cells, which resulted in the induction of autophagic apoptosis and ultimately the inhibition of cancer cell growth and metastasis.

Association between body mass index and colorectal adenomas: Findings from a case-control study in Vietnam

Colorectal cancer is a leading cancer worldwide and in Vietnam. Adenomas (adenomatous polyps) is an important precursor of colorectal cancer. There is currently no study to determine the modifiable risk factors for colorectal adenomas, including body mass index (BMI) in Vietnam. We conducted an individually matched case-control study of 1149 colorectal adenomas and 1145 controls in a large-scale colorectal screening program involving 103 542 individuals aged 40-75 years old in Hanoi, Vietnam. Conditional logistic regression was used to evaluate the association between BMI and colorectal adenomas prevalence, after controlling for potential confounders. Overall, comparing to normal weight (ie, 18.5-22.9 kg/m² ), underweight (ie, BMI < 18.5) was associated with a non-statistically significant increased prevalence of colorectal adenomas (odd ratio [OR] = 1.29 and 95% confident interval [CI]: 0.88-1.87). This association became significant among male (OR = 1.98, 95% CI: 1.20-3.27), male who were ever smokers (OR = 2.59, 95% CI: 1.33-5.03), nonregular exercise (OR = 2.44, 95% CI: 1.26-4.73) and individuals with cardiometabolic disorders (OR = 3.46, 95% CI: 1.19-10.00). The association between underweight and colorectal adenomas did not vary by smoking status, drinking status, family history of cancer, adenomas types or cardiometabolic disorders. No association was observed among obese individuals (BMI ≥ 25). In the population with low prevalence of obesity, we found that the association between BMI and colorectal adenomas followed a reversed J-shape that underweight was associated with increased prevalence. Further studies are, therefore, warranted to replicate our results and to investigate the biologic mechanism the effect of underweight on colorectal adenomas prevalence.

Association between lifestyle and site-specific advanced colorectal lesions in screening with faecal immunochemical test and sigmoidoscopy

BACKGROUND

Lifestyle factors may help to identify individuals at high-risk for colorectal cancer (CRC).

AIMS

To examine the association between lifestyle, referral for follow-up colonoscopy and proximal neoplasia detection in CRC screening.

METHODS

In this observational study, 14,832 individuals aged 50-74 years were invited to faecal immunochemical test (FIT) or sigmoidoscopy screening. Advanced lesions (AL), including advanced adenomas, advanced serrated lesions and CRC were divided according to location: distal-only, or proximal with or without distal AL. We collected information on smoking habit, body mass index and alcohol intake through a questionnaire.

RESULTS

Out of 3,318 FIT and 2,988 sigmoidoscopy participants, 516 (16%) and 338 (11%), respectively, were referred for follow-up colonoscopy after a positive screening test. Two-hundred-and-fifty-six (4%) had distal-only and 119 (2%) proximal AL. In FIT participants, obesity and high alcohol intake were associated with proximal AL; odds ratio (95% confidence interval) 2.68 (1.36-5.26) and 2.16 (1.08-4.30), respectively. In sigmoidoscopy participants, current smoking was associated with proximal AL; 4.58 (2.24-9.38), and current smoking and obesity were associated with referral for colonoscopy; 2.80 (2.02-3.89) and 1.42 (1.01-2.00), respectively.

CONCLUSION

Current smoking, obesity and high alcohol intake were associated with screen-detected proximal colorectal AL. Current smoking and obesity were associated with referral for follow-up colonoscopy in sigmoidoscopy screening.

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.

Prevalence and risk factors for colorectal polyps in a Chinese population: a retrospective study

The incidence of colorectal polyps is rising. Certain types of polyps are considered to be the precursor lesions for colorectal cancers. To investigate the prevalence and related factors of colorectal polyps in Chinese subjects, we first performed a cross-sectional study. A total of 3066 subjects were documented, and the prevalence of colorectal polyps was 18.1%. Then we evaluated the incidence and risk factors of polyps via a retrospective cohort study in the same population. 561 subjects who received at least twice surveillance colonoscopies with available reports during the study period and had no polyp at the first endoscopy were included in the retrospective cohort study, of whom 19.1% developed colorectal polyps. Regular smoking was independently associated with the presence and development of colorectal polyps. Further analyses indicated that polyps were associated with smoking status, daily cigarette consumption, and drinking habit. Moreover, smoking tends to be more relavent to rectal, small and single polyp. In conclusion, colorectal polyp is a common disease in China. Exploring the epidemiology and risk factors may improve the prevention of colorectal polyps, even colorectal cancer.

Hospital-Based Preliminary Observations of Dietary Intake and Physical Activity in Saudi Patients with Colorectal Polyps: A Call for Nutrition Care Integration after Polypectomy Procedure

Aim: In Saudi Arabia, the incidence of colorectal cancer (CRC) is increasing. Lifestyle modification, including diet and physical activity, is as important as the standard procedure of colonoscopy screening in reducing CRC development. I explored the dietary intake, physical activity, and selected nutritional biomarkers in Saudi patients with colorectal polyps, a precursor of CRC. Methods: Thirty polypectomy patients (aged 35–84 years) were recruited from an endoscopy unit at King Abdulaziz University Hospital. Demographic, anthropometric, physical activity, and food frequency data were collected. Plasma C-reactive protein, serum 25-hydroxy vitamin D, and folate levels were measured. Results: The median body mass index (BMI) of the patients was within the overweight cut-off range. The median consumption of carbohydrate and protein was within the recommended dietary allowance (RDA). Median fat consumption was above the RDA, while median fiber intake was below the RDA. Patients met the recommended servings/day of fruits, vegetables, dairy products, and protein but exceeded the recommended intake of fats and sweets. Most patients were non-active, with an inadequate level of serum vitamin D. Conclusion: We observed several risk factors previously associated with CRC, including low levels of physical activity, serum vitamin D, and fiber intake, and high BMI and fat intake among polypectomy patients.

Obesity is an initiator of colon adenomas but not a promoter of colorectal cancer in the Black Women's Health Study

PURPOSE

Evidence for the association of anthropometrics with colorectal neoplasms is limited for African Americans.

METHODS

We examined anthropometric measures with both colorectal adenoma and colorectal cancer (CRC) risk in the ongoing Black Women's Health Study. In a nested case-control analysis, 954 cases of colorectal adenoma were compared with 3,816 polyp-free controls, matched on age and follow-up time. For the CRC analyses, 413 incident CRC cases were identified over a 16-year follow-up (802,783 person-years). Adenoma cases and CRC were verified by medical record review. We used multivariable conditional logistic regression analyses (for adenoma) and Cox proportional hazards analyses (for CRC) that included anthropometric exposures and selected confounders.

RESULTS

Overall body mass index (BMI) and other anthropometric factors were not associated with colorectal adenoma or cancer risk in Black women. However, increased risk of adenoma (but not CRC) was observed among especially related to adenomas in the proximal colon. Among women ≥ 50 years of age, risk of proximal adenoma increased 14% (95% CI 1.00, 1.31), 35% (95% CI 1.12, 1.63), and 25% (0.93, 1.68) with each standard deviation increase in BMI, waist circumference, and waist-to-hip ratio, respectively. None of the anthropometric factors were associated with young onset CRC or adenoma risk.

CONCLUSION

Our results suggest that obesity might be an initiator for colon adenomas but not a promoter for colorectal cancer among Black women.

The Role of Self-Determination in Changing Physical Activity Behavior in People Diagnosed With Bowel Polyps: A Pilot Randomized Controlled Trial

This nonblinded randomized controlled trial investigated the efficacy of a physical activity (PA) intervention underpinned by self-determination theory. Participants (N = 31, mean age 69 years [SD = 4.9]) diagnosed with bowel polyps were randomized to an active lifestyle program (ALP; n = 17) or standard care (n = 14). ALP received supervised exercise and counseling for 6 months. Both groups were followed up at 12 months. Outcomes were change in PA and behavioral regulation. Data were analyzed with intention to treat. At 6 months, differences were observed for behavioral regulation in favor of ALP (p < .05). PA differences were significant for leisure, walking, and vigorous in favor of ALP (p < .05). The self-determination theory can be an effective strategy for promoting PA behavior change in this population, but a larger trial is needed to further explore the utility of the self-determination theory in this context.

A framework for examining how diet impacts tumour metabolism

The way cancer cells utilize nutrients to support their growth and proliferation is determined by cancer cell-intrinsic and cancer cell-extrinsic factors, including interactions with the environment. These interactions can define therapeutic vulnerabilities and impact the effectiveness of cancer therapy. Diet-mediated changes in whole-body metabolism and systemic nutrient availability can affect the environment that cancer cells are exposed to within tumours, and a better understanding of how diet modulates nutrient availability and utilization by cancer cells is needed. How diet impacts cancer outcomes is also of great interest to patients, yet clear evidence for how diet interacts with therapy and impacts tumour growth is lacking. Here we propose an experimental framework to probe the connections between diet and cancer metabolism. We examine how dietary factors may affect tumour growth by altering the access to and utilization of nutrients by cancer cells. Our growing understanding of how certain cancer types respond to various diets, how diet impacts cancer cell metabolism to mediate these responses and whether dietary interventions may constitute new therapeutic opportunities will begin to provide guidance on how best to use diet and nutrition to manage cancer in patients.

Calcium: magnesium intake ratio and colorectal carcinogenesis, results from the prostate, lung, colorectal, and ovarian cancer screening trial

Background

We aimed to evaluate the associations between calcium and various stages of colorectal carcinogenesis and whether these associations are modified by the calcium to magnesium (Ca:Mg) ratio.

Methods

We tested our hypotheses in the prostate lung, colorectal and ovarian cancer screening trial.

Results

Calcium intake did not show a dose–response association with incident adenoma of any size/stage (P-_trend = 0.17), but followed an inverse trend when restricted to synchronous/advanced adenoma cases (P-_trend = 0.05). This inverse trend was mainly in participants with Ca:Mg ratios between 1.7 and 2.5 (P-_trend = 0.05). No significant associations were observed for metachronous adenoma. Calcium intake was inversely associated with CRC (P-_trend = 0.03); the association was primarily present for distal CRC (P-_trend = 0.01). The inverse association between calcium and distal CRC was further modified by the Ca:Mg ratio (P-_interaction < 0.01); significant dose–response associations were found only in participants with a Ca:Mg ratio between 1.7 and 2.5 (P-_trend = 0.04). No associations for calcium were found in the Ca:Mg ratio above 2.5 or below 1.7.

Conclusion

Higher calcium intake may be related to reduced risks of incident advanced and/or synchronous adenoma and incident distal CRC among subjects with Ca:Mg intake ratios between 1.7 and 2.5.

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.

Circulating Levels of Omentin, Leptin, VEGF, and HGF and Their Clinical Relevance with PSA Marker in Prostate Cancer

Background

Prostate cancer (PCa) is the first in terms of occurrence in Europe and second in Poland. The PCa risk factors include: genetic load, obesity, diet rich in fat, hypertriglyceridemia, and exposure to androgens. The prostate-specific antigen (PSA) level may be elevated in prostate cancer or other prostate disorders. Fat tissue secretes adipocytokines, which increase the risk of cancer development and metastasis.

Objectives

The aims of the study were to investigate the relationship between circulating levels of PSA, adipocytokines: omentin, leptin, hepatocyte growth factor (HGF), and vascular endothelial growth factor (VEGF) in serum obtained from patients with benign prostate hyperplasia (BPH) and prostate cancer (PCa).

Methods

Forty patients diagnosed with BPH and forty diagnosed with PCa were assessed for the purpose of the study. The concentrations of omentin, leptin, HGF, and VEGF were determined using enzyme-linked immunosorbent assays (EIA).

Results

PSA level was significantly higher in the PCa group than in BPH (18.2 versus 9 ng/mL, p < 0.01), while volume of prostate gland was significantly higher in the BPH group than in PCa (39.1 versus 31.1 cm³, p = 0.02). HGF, VEGF, omentin, and leptin concentrations were significantly higher in PCa group than in BPH (359.5 versus 294.9 pg/mL, p = 0.04; 179.3 versus 127.3 pg/mL, p < 0.01; 478.8 versus 408.3 ng/mL, p = 0.01; 15.7 versus 11.2 ng/mL, p = 0.02, resp.). The multiple logistic regression analysis demonstrated that only omentin and PSA levels were independent predictors of PCa in studied subjects.

Conclusions

PSA level as well as the level of omentin may be valuable markers of PCa with clinical significance, when compared to PSA.

Association Between Risk Factors for Colorectal Cancer and Risk of Serrated Polyps and Conventional Adenomas

BACKGROUND & AIMS

Serrated polyps (SPs) and conventional adenomas are precursor lesions for colorectal cancer (CRC), but they are believed to arise via distinct pathways. We characterized risk factor profiles for SPs and conventional adenomas in a post hoc analysis of data from 3 large prospective studies.

METHODS

We collected data from the Nurses' Health Study, the Nurses' Health Study 2, and the Health Professionals Follow-up Study on subjects who developed SPs or conventional adenomas. Our analysis comprised 141,143 participants who had undergone lower gastrointestinal endoscopy, provided updated diet and lifestyle data every 2-4 years, and were followed until diagnosis of a first polyp. We assessed 13 risk factors for CRC in patients with SPs or conventional adenomas and examined the associations according to histopathology features.

RESULTS

We documented 7945 SPs, 9212 conventional adenomas, and 2382 synchronous SPs and conventional adenomas during 18-20 years of follow-up. Smoking, body mass index, alcohol intake, family history of CRC, and height were associated with higher risk of SPs and conventional adenomas, whereas higher intake of vitamin D and marine omega-3 fatty acid were associated with lower risk. The associations tended to be stronger for synchronous SPs and conventional adenomas. Smoking, body mass index, and alcohol intake were more strongly associated with SPs than conventional adenomas (P for heterogeneity <.05), whereas physical activity and intake of total folate and calcium were inversely associated with conventional adenomas but not SPs. For SPs and conventional adenomas, the associations tended to be stronger for polyps in the distal colon and rectum, of 10 mm or larger or with advanced histology.

CONCLUSIONS

In an analysis of data from 3 large prospective studies, we found that although SPs and conventional adenomas share many risk factors, some factors are more strongly associated with one type of lesion than the other. These findings provide support for the etiologic heterogeneity of colorectal neoplasia.

Height and body fatness and colorectal cancer risk: an update of the WCRF-AICR systematic review of published prospective studies

PURPOSE

There is no published dose-response meta-analysis on the association between height and colorectal cancer risk (CRC) by sex and anatomical sub-site. We conducted a meta-analysis of prospective studies on the association between height and CRC risk with subgroup analysis and updated evidence on the association between body fatness and CRC risk.

METHODS

PubMed and several other databases were searched up to November 2016. A random effects model was used to calculate dose-response summary relative risks (RR's).

RESULTS

47 studies were included in the meta-analyses including 50,936 cases among 7,393,510 participants. The findings support the existing evidence regarding a positive association of height, general and abdominal body fatness and CRC risk. The summary RR were 1.04 [95% (CI)1.02-1.05, I² = 91%] per 5 cm increase in height, 1.02 [95% (CI)1.01-1.02, I² = 0%] per 5 kg increase in weight, 1.06 [95% (CI)1.04-1.07, I² = 83%] per 5 kg/m2 increase in BMI, 1.02 [95% (CI)1.02-1.03, I² = 4%] per 10 cm increase in waist circumference, 1.03 [95% (CI)1.01-1.05, I² = 16%] per 0.1 unit increase in waist to hip ratio. The significant association for height and CRC risk was similar in men and women. The significant association for BMI and CRC risk was stronger in men than in women.

CONCLUSION

The positive association between height and risk of CRC suggests that life factors during childhood and early adulthood might play a role in CRC aetiology. Higher general and abdominal body fatness during adulthood are risk factors of CRC and these associations are stronger in men than in women.

Obesity, physical activity, and dietary behaviors in an ethnically-diverse sample of cancer survivors with early onset disease

PURPOSE

To assess weight status, physical activity, and dietary behaviors in an ethnically-diverse sample of breast and colorectal cancer survivors with early onset disease (≤ 50 years).

METHODS

Breast and colorectal cancer survivors, diagnosed between 1999 and 2009 with early-stage cancer diagnosed by 50 years of age, were identified through a population-based cancer registry and surveyed. Descriptive and regression analyses were conducted to characterize the sample and identify correlates of lifestyle behaviors.

FINDINGS

The majority of participants (n = 156) were female (83%), insured (84%), and racial/ethnic minorities (29% Asian, 24% Latino, 15% African American). Participants' mean age at response was 50 years and mean time since diagnosis was 9 years. Over half of survivors were overweight or obese. Few participants reported engaging in regular physical activity (31%) and adhering to minimum guidelines for fruit and vegetable consumption (32%). A substantial proportion of survivors consumed fast food in the past week (75%) and nearly half (48%) reported daily consumption of sugar-sweetened beverages. Lower income was associated with inadequate fruit and vegetable intake. Fast food and sugar-sweetened beverage consumption was significantly higher among racial/ethnic minority survivors compared to non-Latino whites.

CONCLUSIONS

High prevalence of overweight and suboptimal adherence to recommended nutrition and physical activity behaviors were observed among cancer survivors with early onset disease. Cancer survivors diagnosed at a young age may benefit from targeted interventions to address overweight and suboptimal nutrition and physical activity.

A mini-review of quality of life as an outcome in prostate cancer trials: patient-centered approaches are needed to propose appropriate treatments on behalf of patients

Background

Patients with prostate cancer (PC) may be ready to make trade-offs between their quantity and their quality of life. For instance, elderly patients may prefer the absence of treatment if it is associated with a low-risk of disease progression, compared to treatments aiming at preventing disease progression but with a substantial deterioration of their Health-Related Quality of Life (HRQoL). Therefore, it seems relevant to compare the treatments by considering both survival and HRQoL. In this mini-review, the aim was to question whether the potential trade-offs between survival and HRQoL are considered in high impact factor journals.

Methods

The study was conducted from the PubMed database for recent papers published between May 01, 2013, and May 01, 2015. We also restricted our search to nine medical journals with 2013 impact factor > 15.

Results

Among the 30 selected studies, only six collected individual HRQoL as a secondary endpoint by using the Functional Assessment of Cancer Therapy-Prostate (FACT-P) questionnaire. In four studies, the time to HRQoL change was analyzed, but its definitions varied. In two studies, the mean changes in HRQoL between the baseline and the 12- or 16-week follow-up were analyzed. None of the six studies reported in a single endpoint both the quantity and the quality of life.

Conclusions

Our mini-review, which only focused on recent publications in journals with high-impact, suggests moving PC clinical research towards patient-centered outcomes-based studies. This may help physicians to propose the most appropriate treatment on behalf of patients. We recommend the use of indicators such as Quality-Adjusted Life-Years (QALYs) as principal endpoint in future clinical trials.

Electronic supplementary material

The online version of this article (10.1186/s12955-018-0870-6) contains supplementary material, which is available to authorized users.

Obesity Is Associated with Early Onset of Gastrointestinal Cancers in California

BACKGROUND

Although it is well known that obesity is a risk factor for gastrointestinal (GI) cancer, it is not well established if obesity can cause earlier GI cancer onset.

METHODS

A cross-sectional study examining the linked 2004-2008 California Cancer Registry Patient Discharge Database was performed to evaluate the association between obesity and onset age among four gastrointestinal cancers, including esophageal, gastric, pancreatic, and colorectal cancers. Regression models were constructed to adjust for other carcinogenic factors.

RESULTS

The diagnosis of obesity (BMI > 30) was associated with a reduction in diagnosis age across all four cancer types: 3.25 ± 0.53 years for gastric cancer, 4.56 ± 0.18 years for colorectal cancer, 4.73 ± 0.73 years for esophageal cancer, and 5.35 ± 0.72 for pancreatic cancer. The diagnosis of morbid obesity (BMI > 40) was associated with a more pronounced reduction in the age of diagnosis: 5.48 ± 0.96 years for gastric cancer, 7.75 ± 0.30 years for colorectal cancer, 7.67 ± 1.26 years for esophageal cancer, and 8.19 ± 1.25 years for pancreatic cancer. Both morbid obesity and obesity remained strongly associated with earlier cancer diagnosis for all four cancer types even after adjusting for other available cancer risk factors.

CONCLUSIONS

The diagnosis of obesity, especially morbid obesity, was associated with a significantly earlier gastrointestinal cancer onset in California. Further research with prospective cohort data may be required to establish the causal relationship between obesity and cancer onset age.

Clinicopathologic distribution of KRAS and BRAF mutations in a Chinese population with colorectal cancer precursor lesions

Investigating the clinical features and corresponding histomorphologic and molecular profiles of precursor lesions of colorectal cancer in a natural population provides new insights into the nature of colorectal cancer, uncovers new screening markers and establishes new prevention strategies for colorectal cancer. In this study, 4302 patients with at least one colorectal polyp from a large colorectal cancer screening program were evaluated and genetic mutations in either KRAS or BRAF were detected in 495 patients. The population-based mutation rates of KRAS and BRAF genes in colorectal polyps within this Chinese patient population were 21.8% and 12.1% respectively. Interestingly, considerable variability in the KRAS and BRAF mutations rates were found among different types of polyps. In a multivariate analysis, presence of villous histology and high-grade dysplasia was associated with KRAS mutations (OR, 3.0; 95% CI, 1.7-5.4 and OR, 3.5; 95% CI 1.9-6.5, respectively), while serrated adenomas and hyperplastic polyps were associated with BRAF V600E mutations (OR, 20.6; 95% CI, 8.2–51.8 and OR, 11.9; 95% CI 4.9–29.0, respectively). KRAS mutations may, in part, drive the histologic progression of adenomas toward a villous histology and higher grades of dysplasia. Mutant BRAF may, in part, drive the histologic progression of adenomas toward serrated histology. Dysplasia may arise from hyperplastic polyps, resulting in the formation of serrated adenomas and potentially the development of colorectal carcinoma.

Obesity-related parameters and colorectal adenoma development

BACKGROUND

Obesity increases the risk of colorectal adenoma and colorectal cancer. However, the obesity-related parameters that are best for assessing the risk of colorectal adenoma development remain unclear. We analyzed the parameters that may best describe the association between obesity and colorectal adenoma development.

METHODS

In this retrospective cohort study, 3405 individuals underwent screening colonoscopy during routine health examinations. We measured body mass index; waist circumference; and metabolic parameters such as high-density lipoprotein-cholesterol, glucose, triglyceride, and systolic blood pressure. We analyzed the risk of developing colorectal adenoma, relative to obesity-related parameters, over a mean interval of 5.8 years from baseline colonoscopy.

RESULTS

In a multivariate analysis, waist circumference was the only obesity-related marker associated with an increased risk of metachronous colorectal adenoma. Men with waist circumferences ≥85 cm and women with waist circumference ≥82 cm had a 31% increased risk of metachronous colorectal adenoma compared to those with smaller waist circumferences [odds ratio (OR) 1.31; 95% confidence interval (CI, 1.09-1.57)]. Other factors associated with metachronous colorectal adenoma were age (OR, 1.03; 95% CI 1.02-1.04), male sex (OR 1.49; 95% CI 1.17-1.88), alcohol consumption ≥3/week (OR 1.33; 95% CI 1.10-1.62), the number of adenoma at baseline (OR 1.21; 95% CI 1.10-1.33), and the presence of advanced adenoma at baseline (OR 1.60; 95% CI 1.24-2.06).

CONCLUSIONS

Our findings suggest that central obesity, represented by waist circumference, is a significant predictor of metachronous colorectal adenoma, independent of body mass index and other metabolic variables.

Higher body mass index is associated with an increased risk of multiplicity in surveillance colonoscopy within 5 years

We aimed to evaluate whether obesity was associated with a certain clinicopathologic characteristics of metachronous CRA. This retrospective longitudinal cohort study included 2,904 subjects who had at least one resected CRA at index colonoscopy and who subsequently underwent one or more surveillance colonoscopies within 5 years. Of the 2,904 subjects, 60.9% (n = 1,769) were normal, 35.8% (n = 1,040) were overweight, and 3.3% (n = 95) were obese. Patients with any metachronous CRA were 53.7% (n = 1,559). In multivariate analyses, higher BMI at index colonoscopy was significantly associated with any metachronous CRA (overweight, OR = 1.07; obese, OR = 1.82; p for trend = 0.049). Regarding the multiplicity, the ORs of ≥ 3, ≥ 4 and ≥ 5 metachronous CRAs significantly increased as index BMI increased (p for trend < 0.001, = 0.007 and = 0.004, respectively). In negative binomial regression regarding the incidence for total number of metachronous CRA, the higher BMI the subject has at the time of index colonoscopy, the more metachronous CRAs the subject will have at the surveillance colonoscopy (p for trend = 0.016). Higher index BMI was significantly associated with the risk of multiple metachronous CRAs on surveillance colonoscopy within 5 years.

Peroxisome Proliferator-Activated Receptor Gamma in Obesity and Colorectal Cancer: the Role of Epigenetics

Peroxisome proliferator-activated receptor gamma (PPARγ) is a nuclear receptor that is deregulated in obesity. PPARγ exerts diverse antineoplastic effects. Attempting to determine the clinical relevance of the epigenetic mechanisms controlling the expression PPARγ and susceptibility to colorectal cancer (CRC) in obese subjects, this study investigated the role of some microRNAs and DNA methylation on the deregulation of PPARγ. Seventy CRC patients (34 obese and 36 lean), 22 obese and 24 lean healthy controls were included. MicroRNA levels were measured in serum. PPARγ promoter methylation was evaluated in peripheral blood mononuclear cells (PBMC). PPARγ level was evaluated by measuring mRNA level in PBMC and protein level in serum. The tested microRNAs (miR-27b, 130b and 138) were significantly upregulated in obese and CRC patients. Obese and CRC patients had significantly low levels of PPARγ. A significant negative correlation was found between PPARγ levels and the studied microRNAs. There was a significant PPARγ promoter hypermethylation in CRC patients that correlated to low PPARγ levels. Our results suggest that upregulation of microRNAs 27b, 130b and 138 is associated with susceptibility to CRC in obese subjects through PPARγ downregulation. Hypermethylation of PPARγ gene promoter is associated with CRC through suppression of PPARγ regardless of BMI.

Metabolic unhealthiness is an important predictor for the development of advanced colorectal neoplasia

Obesity is a well-known risk factor for colorectal neoplasia. Yet, the associations of both metabolic and obesity status with metachronous colorectal neoplasia remain unclear. We conducted a cohort study of 9,331 adults who underwent screening colonoscopy and surveillance colonoscopy. Participants were classified as metabolically healthy if they had no metabolic syndrome component. Participants were categorized into four groups according to body mass index and metabolic status: metabolically healthy non-obese (MHNO; n = 2,745), metabolically abnormal non-obese (MANO; n = 3,267), metabolically healthy obese (MHO; n = 707), and metabolically abnormal obese (MAO; n = 2,612). MAO individuals [n = 159 advanced colorectal neoplasia (AN) cases, 6.1%] and MANO individuals (n = 167 AN cases, 5.1%) had a higher incidence of AN compared with MHNO individuals (n = 79 AN cases, 2.9%). In a multivariable model, the risk of metachronous AN was higher in MANO (hazard ratio [HR] 1.43, 95% confidence interval [CI] 1.12–1.84) and MAO (HR 1.52, 95% CI 1.18–1.96) than in MHNO. In contrast, the risk of metachronous AN was not significantly elevated in MHO. In subgroup analyses, with or without adenoma at baseline, MAO was a risk group for metachronous AN, and MHO was not. Our findings suggest that metabolic unhealthiness is a significant predictor for metachronous AN.

Epidemiology and risk factors of colorectal polyps

The lifetime risk of colorectal cancer (CRC) in the Western world is around 5%. CRC commonly develops from precursor lesions termed polyps, classified as adenomatous or serrated polyps according to growth pattern. Despite the well-known connection between polyps and cancer, most polyps will never develop into CRC. For those that do, the time until CRC development is generally thought of as >10 years. This gives opportunity for interventional strategies to prevent transformation into cancer. This article aims to provide an overview of the epidemiology of and risk factors for colorectal polyps in the average risk population, and will encompass the effect of age, gender, ethnicity, smoking, obesity, alcohol, physical activity, NSAIDs and dietary factors on colorectal polyps.

Epidemiology and biology of physical activity and cancer recurrence

Physical activity is emerging from epidemiologic research as a lifestyle factor that may improve survival from colorectal, breast, and prostate cancers. However, there is considerably less evidence relating physical activity to cancer recurrence and the biologic mechanisms underlying this association remain unclear. Cancer patients are surviving longer than ever before, and fear of cancer recurrence is an important concern. Herein, we provide an overview of the current epidemiologic evidence relating physical activity to cancer recurrence. We review the biologic mechanisms most commonly researched in the context of physical activity and cancer outcomes, and, using the example of colorectal cancer, we explore hypothesized mechanisms through which physical activity might intervene in the colorectal recurrence pathway. Our review highlights the importance of considering pre-diagnosis and post-diagnosis activity, as well as cancer stage and timing of recurrence, in epidemiologic studies. In addition, more epidemiologic research is needed with cancer recurrence as a consistently defined outcome studied separately from survival. Future mechanistic research using randomized controlled trials, specifically those demonstrating the exercise responsiveness of hypothesized mechanisms in early stages of carcinogenesis, are needed to inform recommendations about when to exercise and to anticipate additive or synergistic effects with other preventive behaviors or treatments.

Measurement of DNA damage in peripheral blood by the γ-H2AX assay as predictor of colorectal cancer risk

The detection of γ-H2AX focus is one of the most sensitive ways to monitor DNA double-strand breaks (DSBs). Although changes in γ-H2AX activity have been studied in tumor cells in colorectal cancer (CRC), changes in peripheral blood lymphocytes (PBLs) have not been examined previously. We hypothesize that higher levels of irradiation-induced γ-H2AX in PBLs may be associated with an elevated risk of colorectal cancer (CRC). In a case-control study, the baseline and ionizing radiation (IR)-induced γ-H2AX levels in PBLs from frequency-matched 320 untreated CRC patients and 320 controls were detected by a laser scanning cytometer-based immunocytochemical method. We used unconditional multivariable logistic regression to evaluate CRC risk by using the ratio of IR-induced γ-H2AX to the baseline levels with adjustment of age, sex and smoking status. We found CRC cases had significantly higher γ-H2AX ratio (1.5 vs. 1.41, P<0.0001) compared with controls. When using the median γ-H2AX ratio of controls as a cutoff point, we found higher γ-H2AX ratio was significantly associated with an increased risk of CRC (OR=6.72, 95% CI=4.54-9.94). Quartile analyses also showed significant dose-response relationship between higher γ-H2AX ratio and increased risk of CRC (P for trend<0.0001). Age, sex, BMI and smoking status also influenced the association of γ-H2AX ratio with CRC risk; however, no interactions with γ-H2AX ratio were observed. These results support the premise that DSBs in peripheral blood as measured by γ-H2AX level might represent an intermediate phenotype to assess the risk of CRC. Future prospective studies are necessary to confirm our findings in independent populations.

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.

Polyp Detection Rates among Body Mass Index Categories at First Screening Colonoscopy

In the United States, obesity is an epidemic and colorectal cancer is the second deadliest cancer for men and women. A link between obesity and colorectal adenomas and carcinoma has been suggested but not proven. We sought out to determine if obesity was associated with increased rates of polyp formation. All patients undergoing a first screening colonoscopy by one of the participating endoscopists at Thomas Jefferson University Hospital from January 2012 to March 2015 were considered for the study. Their demographics, body mass index (BMI), and colonoscopy findings were recorded at the time of the procedure and prospectively maintained in our database. The final pathologic diagnosis was recorded for each participant as it became available. A total of 758 subjects were included. Of these, 22 per cent had a BMI <25 kg/m2, 29 per cent had a BMI between 25 and 29.9 kg/m2, and 49 per cent had a BMI of at least 30 kg/m2. Overall, 21.9 per cent of the participants were found to have at least one adenomatous polyp. The polyp detection rates were 24.4 per cent in the group with a BMI less than 25, 20.5 per cent in the overweight group, and 21.6 per cent in the obese group. Our study included 56 super obese individuals with a BMI ≥45 kg/m2. About 17.9 per cent of subjects in the super obese group had an adenomatous polyp. There were no differences in the incidence of adenomatous polyps between BMI categories in our study.

Weight Change and Obesity Are Associated with a Risk of Adenoma Recurrence

BACKGROUND

Obesity is reportedly a risk factor for colorectal adenoma. However, the influence of weight change and obesity on colorectal adenoma recurrence is unclear.

AIM

To investigate whether weight change and obesity are associated with recurrence and development of colorectal adenoma.

PATIENTS AND METHODS

Of 62,171 asymptomatic subjects who underwent a colonoscopy for a heath checkup between 2010 and 2011, this longitudinal study was performed with the 5297 subjects who underwent another colonoscopy between 2012 and 2013. The risk of recurrence or development of adenoma according to quartiles of weight change (<-1.6, -1.6 to 0.1, 0.2-1.8, and ≥1.9 kg) and baseline BMI categories (<25, 25-29, and ≥30 kg/m(2)) was assessed using Cox proportional hazards modeling.

RESULTS

The average period between visits 1 and 2 was 2.2 ± 0.6 years. Among the 2176 subjects with adenomas, the risk of recurrence of any adenoma increased with increasing weight change quartiles (p for trend = 0.030), whereas the risk of recurrence of advanced adenoma was not associated with weight change (p for trend = 0.852). The risk of recurrence of advanced adenoma increased with increasing baseline BMI categories (p for trend = 0.029). Among 3121 subjects with no adenoma, the risk of developing any adenoma increased with increasing baseline BMI categories (p for trend <0.001). However, the risk of developing any or advanced adenoma was not associated with weight change.

CONCLUSIONS

Weight change over 2.2 years affected adenoma recurrence and obesity was related to advanced adenoma recurrence and adenoma development.

A Nested Case-Control Study of Metabolically Defined Body Size Phenotypes and Risk of Colorectal Cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC)

BACKGROUND

Obesity is positively associated with colorectal cancer. Recently, body size subtypes categorised by the prevalence of hyperinsulinaemia have been defined, and metabolically healthy overweight/obese individuals (without hyperinsulinaemia) have been suggested to be at lower risk of cardiovascular disease than their metabolically unhealthy (hyperinsulinaemic) overweight/obese counterparts. Whether similarly variable relationships exist for metabolically defined body size phenotypes and colorectal cancer risk is unknown.

METHODS AND FINDINGS

The association of metabolically defined body size phenotypes with colorectal cancer was investigated in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Metabolic health/body size phenotypes were defined according to hyperinsulinaemia status using serum concentrations of C-peptide, a marker of insulin secretion. A total of 737 incident colorectal cancer cases and 737 matched controls were divided into tertiles based on the distribution of C-peptide concentration amongst the control population, and participants were classified as metabolically healthy if below the first tertile of C-peptide and metabolically unhealthy if above the first tertile. These metabolic health definitions were then combined with body mass index (BMI) measurements to create four metabolic health/body size phenotype categories: (1) metabolically healthy/normal weight (BMI < 25 kg/m2), (2) metabolically healthy/overweight (BMI ≥ 25 kg/m2), (3) metabolically unhealthy/normal weight (BMI < 25 kg/m2), and (4) metabolically unhealthy/overweight (BMI ≥ 25 kg/m2). Additionally, in separate models, waist circumference measurements (using the International Diabetes Federation cut-points [≥80 cm for women and ≥94 cm for men]) were used (instead of BMI) to create the four metabolic health/body size phenotype categories. Statistical tests used in the analysis were all two-sided, and a p-value of <0.05 was considered statistically significant. In multivariable-adjusted conditional logistic regression models with BMI used to define adiposity, compared with metabolically healthy/normal weight individuals, we observed a higher colorectal cancer risk among metabolically unhealthy/normal weight (odds ratio [OR] = 1.59, 95% CI 1.10-2.28) and metabolically unhealthy/overweight (OR = 1.40, 95% CI 1.01-1.94) participants, but not among metabolically healthy/overweight individuals (OR = 0.96, 95% CI 0.65-1.42). Among the overweight individuals, lower colorectal cancer risk was observed for metabolically healthy/overweight individuals compared with metabolically unhealthy/overweight individuals (OR = 0.69, 95% CI 0.49-0.96). These associations were generally consistent when waist circumference was used as the measure of adiposity. To our knowledge, there is no universally accepted clinical definition for using C-peptide level as an indication of hyperinsulinaemia. Therefore, a possible limitation of our analysis was that the classification of individuals as being hyperinsulinaemic-based on their C-peptide level-was arbitrary. However, when we used quartiles or the median of C-peptide, instead of tertiles, as the cut-point of hyperinsulinaemia, a similar pattern of associations was observed.

CONCLUSIONS

These results support the idea that individuals with the metabolically healthy/overweight phenotype (with normal insulin levels) are at lower colorectal cancer risk than those with hyperinsulinaemia. The combination of anthropometric measures with metabolic parameters, such as C-peptide, may be useful for defining strata of the population at greater risk of colorectal cancer.

Validation of the Asia Pacific Colorectal Screening (APCS) score in a Western population: An alternative screening tool

BACKGROUND AND AIM

Colorectal cancer (CRC) screening is based on colonoscopy or fecal occult blood tests, but is imperfect and costly. The Asia Pacific Colorectal Screening Score (APCS) is derived from age, sex, family history of CRC, and smoking history and has been validated in Asian populations. Validation in a Western population is, however, yet to be tested.

METHODS

In a teaching hospital, patients underwent colonoscopy for standard indications and screening over 18 months. Data was collected on age, sex, family history of CRC, smoking, weight, ethnicity, and symptoms. Evaluation of the APCS to predict colonoscopy findings (polyps, adenoma, high risk adenoma, and CRC) was performed.

RESULTS

A total of 645 patients were prospectively recruited (46.7% male, median age 57 years); 17.8% were average risk (AR), 50.9% were moderate risk (MR), and 31.3% high risk (HR) on APCS. High risk adenomas (AA) were seen in 14.9% of the HR, 5.2% MR, and 0.9% LR patients, P < 0.0001. Comparing HR and MR to AR patients demonstrated significantly elevated relative risk (RR) for AA: 17.1 (95% confidence interval [CI] 2.4-123; P = 0.0001), and adenoma 6.0 (0.80-44.3; P = 0.044). Comparing HR to MR groups for AA, the RR was 2.87 (1.62-5.06; P = 0.0001). Symptoms did not predict findings (odds ratio [OR]: 1.06 [0.75-1.48]; P = 0.75). Body mass index (BMI) <20 kg/m(2) was protective against colonic polyps (OR: 0.28, 95%CI: 0.11-0.74; P = 0.010), adenoma (0.08, 0.01-0.62; P = 0.015), and AA (perfect prediction, OR 2.35 × 10(-8)).

CONCLUSIONS

APCS predicts colonic findings in a Western population, to a greater extent than in Asians, independent to symptoms. Low body weight carries a strong protective effect against colonic neoplasia.

Improving the utility of colonoscopy: Recent advances in practice

Colonoscopy is a frequently performed diagnostic and therapeutic test and the primary screening tool in several nationalized bowel cancer screening programs. There has been a considerable focus on maximizing the utility of colonoscopy. This has occurred in four key areas: Optimizing patient selection to reduce unnecessary or low yield colonoscopy has offered cost-benefit improvements in population screening. Improving quality assurance, through the development of widely accepted quality metrics for use in individual practice and the research setting, has offered measurable improvements in colonoscopic yield. Significant improvements have been demonstrated in colonoscopic technique, from the administration of preparation to the techniques employed during withdrawal of the colonoscope. Improved techniques to avoid post-procedural complications have also been developed-further maximizing the utility of colonoscopy. The aim of this review is to summarize the recent evidence-based advances in colonoscopic practice that contribute to the optimal practice of colonoscopy.

Paraoxonase-1 and arylesterase activities in patients with colorectal cancer

BACKGROUND

The aim of this study was to evaluate paraoxonase-1 (PON1) and arylesterase (ARE) activities and oxidative stress status in patients with colorectal carcinomas (CRC).

MATERIALS AND METHODS

Thirty-three patients (20 male, 13 female) with CRC and 30 healthy controls were enrolled in the study. Blood samples were obtained from the CRC patients before adjuvant therapy. Serum samples from CRC patients and healthy controls were analyzed for PON1 and ARE activities.

RESULTS

The PON1 and ARE activities of the patients with CRC were significantly higher compared to those of the control group (PON1 activity is 125.35±20.07 U/L for CRC patients and 1.22±0.48 U/L for control group, P<0.001; ARE activity is 160.76±10.79 U/L for CRC patients). ARE levels showed a positive correlation with smoking status (P=0.04). PON1 activity was higher in colon carcinoma patients (135.95±19.3 U/L) rather than rectal carcinoma patients (97.08±5.24 U/L) but it was not statistically significant (P=0.72).

CONCLUSION

Serum PON1 activity is increased in patients with CRC, and serum ARE levels showed a positive correlation with smoking status. PON1 activity was higher in colon carcinoma patients. There is no other study in literature investigating these activities for CRC patients. It should be reevaluated by larger clinical trials.

Obesity, Aspirin, and Risk of Colorectal Cancer in Carriers of Hereditary Colorectal Cancer: A Prospective Investigation in the CAPP2 Study

PURPOSE

In the general population, increased adiposity is a significant risk factor for colorectal cancer (CRC), but whether obesity has similar effects in those with hereditary CRC is uncertain. This prospective study investigated the association between body mass index and cancer risk in patients with Lynch syndrome (LS).

PATIENTS AND METHODS

Participants with LS were recruited to the CAPP2 study, in which they were randomly assigned to receive aspirin 600 mg per day or aspirin placebo, plus resistant starch 30 g per day or starch placebo (2 × 2 factorial design). Mean intervention period was 25.0 months, and mean follow-up was 55.7 months.

RESULTS

During follow-up, 55 of 937 participants developed CRC. For obese participants, CRC risk was 2.41× (95% CI, 1.22 to 4.85) greater than for underweight and normal-weight participants (reference group), and CRC risk increased by 7% for each 1-kg/m(2) increase in body mass index. The risk of all LS-related cancers in obese people was 1.77× (95% CI, 1.06 to 2.96; P = .03) greater than for the reference group. In subgroup analysis, obesity was associated with 3.72× (95% CI, 1.41 to 9.81) greater CRC risk in patients with LS with MLH1 mutation, but no excess risk was observed in those with MSH2 or MSH6 mutation (P = .5). The obesity-related excess CRC risk was confined to those randomly assigned to the aspirin placebo group (adjusted hazard ratio, 2.75; 95% CI, 1.12 to 6.79; P = .03).

CONCLUSION

Obesity is associated with substantially increased CRC risk in patients with LS, but this risk is abrogated in those taking aspirin. Such patients are likely to benefit from obesity prevention and/or regular aspirin.

Chronic inflammation and risk of colorectal and other obesity-related cancers: The health, aging and body composition study

Evidence of the association between chronic inflammation and the risk of colorectal cancer (CRC) and other obesity-related cancers (OBRC) remains inconsistent, possibly due to a paucity of studies examining repeated measures of inflammation. In the Health ABC prospective study of 2,490 adults aged 70-79 years at baseline, we assessed whether circulating levels of three markers of systemic inflammation, IL-6, CRP and TNF-α, were associated with the risk of CRC and OBRC, a cluster including cancers of pancreas, prostate, breast and endometrium. Inflammatory markers were measured in stored fasting blood samples. While only baseline measures of TNF-α were available, IL-6 and CRP were additionally measured at Years 2, 4, 6 and 8. Multivariable Cox models were fit to determine whether tertiles and log-transformed baseline, updated and averaged measures of CRP and IL-6 and baseline measures of TNF-α were associated with the risk of incident cancer(s). During a median follow-up of 11.9 years, we observed 55 and 172 cases of CRC and OBRC, respectively. The hazard of CRC in the highest tertile of updated CRP was more than double that in the lowest tertile (HR = 2.29; 95% CI: 1.08-4.86). No significant associations were seen between colorectal cancer and IL-6 or TNF-α. Additionally, no significant associations were found between obesity-related cancers and the three inflammatory markers overall, but we observed a suggestion of effect modification by BMI and NSAID use. In summary, in this population, higher CRP levels were associated with increased risk of CRC, but not of OBRC. The findings provide new evidence that chronically elevated levels of CRP, as reflected by repeated measures of this marker, may play a role in colorectal carcinogenesis in older adults.

Appropriate surgical treatment of colorectal cancer patients with acute intestinal obstruction

AIM: To assess the clinical effects of surgical treatment of colorectal cancer patients with acute intestinal obstruction.

METHODS: From January 2008 to January 2011, 108 patients with acute obstructing colorectal cancer underwent surgical treatment at Chengde Medical College Hospital. Postoperative complications and perioperative death were recorded.

RESULTS: The postoperative complication rate was 12.93%. The complication rate was 7.39% for one-stage resection, 3.70% for one-stage colostomy surgery, and 0.92% for simple colostomy surgery and bypass surgery, which differed significantly between the groups (P < 0.05). A total of five patients died, with a mortality rate of 4.61%. The mortality rate was 1.85% for one-stage resection, 0.92% for one-stage colostomy surgery, and 0.92% for simple colostomy surgery and bypass surgery, which did not differ significantly between the groups (P > 0.05).

CONCLUSION: Surgical treatment of patients with acute obstructing colorectal cancer has good clinical efficacy. Clinicians should select the appropriate surgical approach and strengthen the perioperative care in order to reduce the incidence of postoperative complications and mortality.

Fetal growth and subsequent maternal risk of colorectal cancer

BACKGROUND

High birth weight has been associated with subsequent increased risk of breast cancer in the infant's mother, possibly related to maternal estrogen and growth factor pathways. However, its association with maternal risk of colorectal cancer, the third most common cancer among women, is unknown.

METHODS

We conducted a national cohort study of 1,838,509 mothers who delivered 3,590,523 babies in Sweden in 1973-2008, followed up for colorectal cancer incidence through 2009.

RESULTS

There were 7,318 mothers diagnosed with colorectal cancer in 36.8 million person-years of follow-up. After adjusting for maternal age, body mass index, diabetes, and other potential confounders, high fetal growth was associated with a subsequent increased risk of colorectal cancer in the mother [incidence rate ratio (IRR) per additional 1 SD relative to mean birth weight for gestational age and sex, 1.05; 95% confidence intervals (CI), 1.03-1.07; P < 0.0001]. Each 1,000 g increase in the infant's birth weight was associated with a 12% increase in the mother's subsequent risk of colorectal cancer (IRR, 1.12; 95% CI, 1.07-1.17; P < 0.0001). Multiple gestation was also independently associated with increased maternal risk of colorectal cancer (IRR for twin or higher order vs. singleton, 1.22; 95% CI, 1.04-1.44; P = 0.02).

CONCLUSION

In this large cohort study, high fetal growth and multiple gestation were independently associated with subsequent higher maternal risk of colorectal cancer. These findings warrant further investigation of maternal growth factor and estrogen pathways in the etiology of colorectal cancer.

IMPACT

If confirmed, our findings may help identify subgroups of women at high risk of colorectal cancer.

BMI and lifetime changes in BMI and cancer mortality risk

Body Mass Index (BMI) is known to be associated with cancer mortality, but little is known about the link between lifetime changes in BMI and cancer mortality in both males and females. We studied the association of BMI measurements (at baseline, highest and lowest BMI during the study-period) and lifetime changes in BMI (calculated over different time periods (i.e. short time period: annual change in BMI between successive surveys, long time period: annual change in BMI over the entire study period) with mortality from any cancer, and lung, colorectal, prostate and breast cancer in a large cohort study (n=8,645. Vlagtwedde-Vlaardingen, 1965-1990) with a follow-up on mortality status on December 31^st 2008. We used multivariate Cox regression models with adjustments for age, smoking, sex, and place of residence. Being overweight at baseline was associated with a higher risk of prostate cancer mortality (hazard ratio (HR) =2.22; 95% CI 1.19-4.17). Obesity at baseline was associated with a higher risk of any cancer mortality [all subjects (1.23 (1.01-1.50)), and females (1.40 (1.07-1.84))]. Chronically obese females (females who were obese during the entire study-period) had a higher risk of mortality from any cancer (2.16 (1.47-3.18), lung (3.22 (1.06-9.76)), colorectal (4.32 (1.53-12.20)), and breast cancer (2.52 (1.15-5.54)). We found no significant association between long-term annual change in BMI and cancer mortality risk. Both short-term annual increase and decrease in BMI were associated with a lower mortality risk from any cancer [all subjects: (0.67 (0.47-0.94)) and (0.73 (0.55-0.97)), respectively]. In conclusion, a higher BMI is associated with a higher cancer mortality risk. This study is the first to show that short-term annual changes in BMI were associated with lower mortality from any type of cancer.

Colorectal cancer screening and prevention in women

Colorectal cancer (CRC) is one of the leading cancers and cause of cancer deaths in American women and men. Females and males share a similar lifetime cumulative risk of CRC however, substantial differences in risk factors, tumor biology, and effectiveness of cancer prevention services have been observed between them. This review distills the evidence documenting the unique variation observed between the genders relating to CRC risk factors, screening and prevention. Consistent evidence throughout the world demonstrates that women reach equivalent levels of adenomas and CRC as men but it occurs nearly a decade later in life than in their male counterparts. Women have a higher proportion of tumors which are hypermethylated, have microsatellite instability and located in the proximal colon suggesting the serrated pathway may be of greater consequence in them than in men. Other CRC risk factors such as smoking, diet and obesity have been shown to have disparate effects on women which may related to interactions between estrogen exposure, body fat distribution, and the biologic underpinnings of their tumors. There is data showing the uptake, choice, and efficacy of different CRC screening methods in women is dissimilar to that in men. The mortality benefit from FOBT, sigmoidoscopy, and protection from interval CRC by colonoscopy appears to be lower in women than men. A greater understanding of these gender idiosyncrasies will facilitate an personalized approach to CRC prevention and should ultimately lead to a reduced burden of disease.