Association Between Body Size and Colorectal Adenoma Recurrence

XSome authors have assessed the link between obesity and colon adenoma risk. Moreover, it has been reported that obesity could increase the risk of proximal adenoma development. Accordingly, obese patients may have a distinctive pattern of adenoma recurrence. AIM: To determine whether metachronous adenoma features differ between obese and non-obese subjects submitted to colonoscopy surveillance. We prospectively evaluated all patients over 18 years old that underwent surveillance colonoscopy at our institution between June 2013 and June 2014. Date of prior colonoscopy was registered. A body mass index ≥ 30 was used to define obesity. Analysis looking for variables significantly associated with metachronous adenoma was performed. Metachronous adenoma rate was compared between obese and non-obese subjects, as well as size, location, morphological and histopathological characteristics. Overall, 825 subjects were enrolled. Median time of surveillance colonoscopy was 38.9 months. Obesity was statistically more frequent in those subjects with metachronous adenomas (40% vs 25.71%, p < 0.001). On multivariate analysis, obesity [OR 1.7 (1.01-2.9)] and age [OR 1.02 (1-1.05)] were independently associated with metachronous adenoma presence. Obesity was also significantly associated with a higher risk of right colon adenomas [OR 2.4 (1.76-3.26)] and advanced adenoma [OR 1.99 (1.29-3.06)]. The risk is significantly higher in men and in those with a family history of colorectal cancer/adenoma. Obesity was associated with a higher risk of metachronous adenomas on surveillance colonoscopy. A higher risk of right-sided lesions and advanced adenomas was also found in this population.

1. Edmonds M, McGuire H, Price J. Exercise therapy for chronic fatigue syndrome. Cochrane Database Syst Rev. 2004;(3):CD003200. 2. Wearden AJ, Morriss RK, Mullis R, et al. Randomised, double-blind, placebocontrolled treatment trial of fluoxetine and graded exercise for chronic fatigue syndrome. Br J Psychiatry. 1998;172:485-490. 3. Powell P, Bentall RP, Nye FJ, Edwards RH. Randomised controlled trial of patient education to encourage graded exercise in chronic fatigue syndrome. BMJ. 2001;322(7283):387-390.

Gastrointestinal (GI) malignancies are a diverse group of tumors along the GI tract with distinct histopathologic features and clinical behavior. Globally, colorectal, gastric, esophageal, liver, and pancreatic cancers represent 5 of the top 10 causes of cancer mortality, and account for approximately 1.9 million cancer deaths per year. Directing resources solely on researching and treating advanced cancers would be unsustainable. Consequently, the importance of conducting cancer prevention research cannot be overemphasized, as effective cancer prevention strategies may reduce both cancer incidence and mortality. This chapter focuses on preventive interventions, which encompass primary, secondary, and tertiary prevention. We will present the latest evidence on prevention strategies involving diet, physical activity, weight loss, and chemoprevention of common GI malignancies. Developing an effective cancer prevention strategy requires an understanding of the carcinogenesis sequence of each individual cancer. For instance, intraepithelial neoplasia is a premalignant condition that can be detected and treated in order to halt the carcinogenesis sequence. In addition to efficacy, an effective cancer prevention intervention must have a low threshold for toxicity – since the at-risk population is typically free of malignancy at the time of intervention. The bulk of this chapter discusses colorectal cancer prevention strategies due to the vast amount of research conducted. However, we will also discuss preventive strategies of the major GI cancers: anal, esophageal, gastric, pancreatic, and hepatobiliary. Our focus throughout this chapter is high-quality evidence from clinical trials (level 1 evidence) or consistent reports from observational studies (level 2 evidence), as supported by experimental results.

Background and study aims Gastroenterologists are encountering a rising number of obese patients requiring colonoscopy. Existing literature regarding colonoscopy outcomes in this population is scant and conflicting. We analyzed a nationwide cohort of patients to identify the effects of body mass index (BMI) on colonoscopy success, efficacy, and tolerability.Patients and methods The Clinical Outcomes Research Initiative (CORI) endoscopic database was queried for all colonoscopies in adults between 2008–2014. Patients were stratified into four cohorts based on BMI classification for comparison. Multivariable analysis was performed to identify the effect of BMI on procedure outcome, efficacy and tolerability.Results Of 41,401 procedures, 27,696 met study inclusion criteria. Of these, 49.4 % were performed for colorectal cancer screening, most commonly under anesthesia directed sedation. Patient discomfort was the reason for an incomplete colonoscopy in 18.7 % of all cases, and more frequent among the overweight and obese cohorts. An inadequate bowel preparation was most common in the class III obesity cohort. Compared to the normal BMI group, a BMI ≥ 30 and < 40 kg/m2was associated with an increased odds of an incomplete colonoscopy (P = 0.001for overweight,P = 0.0004 for class I/II obesity), longer procedure (P < 0.05 for all) and poorer tolerance (P < 0.0001 for class I/II obesity,P = 0.016 for class III obesity). Anesthesia-administered sedation was more commonly used than endoscopist directed sedation amongst the obese cohort compared with the normal BMI cohort (P < 0.0001).Conclusions Endoscopists should consider the increased odds of incomplete colonoscopy, longer procedures, and poorer tolerance when performing colonoscopy in obese patients to improve clinical management and procedural outcome.

Objective To evaluate the impact of a diet and physical activity intervention (BeWEL) on weight change in people with a body mass index >25 weight (kg)/height (m)2 at increased risk of colorectal cancer and other obesity related comorbidities.Design Multicentre, parallel group, randomised controlled trial.Setting Four Scottish National Health Service health boards.Participants 329 overweight or obese adults (aged 50 to 74 years) who had undergone colonoscopy after a positive faecal occult blood test result, as part of the national bowel screening programme, and had a diagnosis of adenoma confirmed by histopathology. 163 were randomised to intervention and 166 to control.Intervention Participants were randomised to a control group (weight loss booklet only) or 12 month intervention group (three face to face visits with a lifestyle counsellor plus monthly 15 minute telephone calls). A goal of 7% reduction in body weight was set and participants received a personalised energy prescription (2508 kJ (600 kcal) below that required for weight maintenance) and bodyweight scales. Motivational interviewing techniques explored self assessed confidence, ambivalence, and personal values concerning weight. Behavioural strategies included goal setting, identifying intentions of implementation, self monitoring of body weight, and counsellor feedback about reported diet, physical activity, and weight change.Main outcome measures The primary outcome was weight change over 12 months. Secondary outcomes included changes in waist circumference, blood pressure, fasting cardiovascular biomarkers, and glucose metabolism variables, physical activity, diet, and alcohol consumption.Results At 12 months, data on the primary outcome were available for 148 (91%) participants in the intervention group and 157 (95%) in the control group. Mean weight loss was 3.50 kg (SD 4.91) (95% confidence interval 2.70 to 4.30) in the intervention group compared with 0.78 kg (SD 3.77) (0.19 to 1.38) in the control group. The group difference was 2.69 kg (95% confidence interval 1.70 to 3.67). Differences between groups were significant for waist circumference, body mass index, blood pressure, blood glucose level, diet, and physical activity. No reported adverse events were considered to be related to trial participation.Conclusions Significant weight loss can be achieved by a diet and physical activity intervention initiated within a national colorectal cancer screening programme, offering considerable potential for risk reduction of disease in older adults.Trial registration Current Controlled Trials ISRCTN53033856.

Targeting risk groups for screening

With more than 145,000 new cases and almost 50,000 deaths each year in men and women combined, colorectal cancer (CRC) is the most common visceral cancer and the second most common of all fatal cancers in the United States.[1] Colorectal adenomas (CRAs) are benign neoplasms and the precursors to most CRCs,[2] with the serrated adenoma (SA) now recognized as another premalignant lesion, particularly in the proximal (right) colon.[3] CRC prevention has focused on the detection and removal of polypoid neoplasms. However, non-polypoid, flat or depressed colorectal neoplasms are relatively common lesions and have a greater association with carcinoma compared with polypoid neoplasms.[4,5]

Obesity has been linked to suboptimal bowel preparation but this association has not been conclusively investigated in prospective studies. Our objective was to determine whether any relationship exists between obesity as measured by body mass index (BMI) and quality of bowel preparation. Adult patients who presented for outpatient colonoscopy at a single urban ambulatory surgery center within a 6-month period and fulfilled inclusion criteria were prospectively enrolled for the study. Patients were divided by BMI into subcategories based on the World Health Organization international classification of obesity. The Modified Aronchick scale was used to assess bowel preparation for colonoscopy. A univariate and multivariate analysis was used to determine a possible association between BMI and poor preparation. A total of 1429 patients were evaluated. On the basis of inclusion criteria, 1314 subjects were analyzed, out of which 73% were overweight or obese. Inadequate bowel preparation was noted in 21.1% of patients. There was no correlation between obesity and the quality of the bowel preparation. Male gender (P=0.002), diabetes mellitus (P<0.0001), liver cirrhosis (P=0.001), coronary artery disease (P=0.003), refractory constipation (P<0.0001), and current smoking (P=0.01) were found to be independently predictive of poor bowel preparation. Increased BMI is not predictive of suboptimal bowel preparation for colonoscopy. The results of our study are pivotal given the increased risk of colorectal cancer in obese patients and their known lower rate of colorectal cancer screening in certain populations. It is important to avoid subjecting these patients to an intensive bowel preparation that may further discourage screening in a patient population that requires it.

Obesity is a risk factor for colorectal neoplasia. Lifestyle modifications, including weight loss, have been advocated to reduce the risk. However, no prospective study has evaluated whether weight loss actually affects adenoma recurrence. The aim of this study was to examine whether weight change (loss or gain) over 4 years is associated with adenoma recurrence. A total of 1826 patients with colorectal adenoma in the Polyp Prevention Trial had their height and weight measured at baseline. Adenoma recurrence was determined by end of trial colonoscopy 4 years after study entry when patients' weights were re-measured. Poisson regression models were used to evaluate body mass index (BMI), weight change over 4 years, and the risk of any adenoma and advanced adenoma recurrence. Adenoma recurrence was observed in 723 patients (39.6%), 118 (6.5%) of whom had advanced adenoma recurrence. Among those with baseline BMI < 25 kg/m² (n = 466), BMI 25-29 kg/m² (n = 868), and BMI ≥ 30 kg/m² (n = 492), the recurrence rate was 34.5%, 41.0%, and 41.9%, respectively. Obesity was associated with an increased risk of adenoma recurrence (RR = 1.19; 95%CI 1.01-1.39) and advanced adenoma recurrence (RR = 1.62; 95%CI 1.01-2.57). However, when compared with those with relatively stable weight (weight change < 5 lb) over the 4-year trial, weight gain or loss was not associated with adenoma recurrence. This was consistent, regardless of the baseline BMI. Weight loss or gain over 4 years does not affect adenoma recurrence. This study does not support weight loss alone as an effective intervention for reducing adenoma recurrence.

The recurrence of colorectal polyps is caused by various factors and leads to the carcinogenesis of colorectal cancer, which ranks third in incidence and fourth in mortality among cancers worldwide. The potential risk factors for colorectal polyp recurrence have been demonstrated in multiple trials. However, an article that pools and summarizes the various results is needed. This review enumerates and analyzes some risk factors in terms of patient characteristics, procedural operations, polyp characteristics, and dietary aspects to propose some effective prophylactic measures. This review aimed to provide a reference for clinical application and guide patients to prevent colorectal polyp recurrence in a more effective manner.