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

Colorectal Cancer and Central Obesity

Importance

The proportion of colorectal cancer (CRC) cases attributable to excess weight, known as population attributable fraction (PAF), has been commonly based on measures of body mass index (BMI). Central obesity metrics, such as waist circumference (WC) and waist to hip ratio (WHR), are potentially better indicators of adiposity and have demonstrated stronger associations with CRC incidence.

Objectives

To examine PAFs of CRC cases that are attributable to high WC and WHR and compare them to those attributable to high BMI.

Design, Setting, and Participants

This population-based UK Biobank cohort study included 458 543 individuals aged 40 to 69 years at recruitment (March 2006 to July 2010) living within a reasonable distance of the 22 assessment centers across the UK. The analyses were conducted between May and July 2024.

Exposures

Exposures were BMI, as a measure of general obesity, and WC and WHR, as indicators of central obesity.

Main Outcomes and Measures

Hazard ratios (HRs) and corresponding 95% CIs were calculated for the associations of BMI, WC, and WHR with CRC incidence. The PAFs and 95% CIs of CRC cases attributable to high BMI, WC, and WHR were also calculated.

Results

A total of 458 543 participants (median [IQR] age, 57 [50-63] years; 244 351 [53.3%] female) were included in the study. During a median follow-up of 11.8 (IQR, 10.9-12.5) years, 5944 participants were diagnosed with CRC. The HRs for the association with CRC incidence were notably smaller for BMI (HR for the highest vs lowest BMI quartile, 1.23; 95% CI, 1.14-1.33) than for WC (HR for the highest vs lowest WC quartile, 1.37; 95% CI, 1.27-1.49) and WHR (HR for the highest vs lowest WHR quartile, 1.40; 95% CI, 1.29-1.51); these associations became comparable only after accounting for possible reverse causality by excluding the initial years of follow-up. Similarly, the PAF of CRC for high BMI was 9.9% (95% CI, 5.5%-14.4%), substantially lower than the PAFs for high WC and WHR, which were 17.3% (95% CI, 12.3%-22.1%) and 17.6% (95% CI, 12.9%-22.2%), respectively. After excluding the initial 7 years of follow-up, PAF estimates became analogous across all measures of obesity and were 15.7% (95% CI, 8.9%-22.4%) for BMI, 16.9% (95% CI, 9.8%-23.8%) for WC, and 18.0% (95% CI, 11.5%-24.6%) for WHR.

Conclusions and Relevance

In this cohort study of approximately half a million participants, the PAF of CRC attributable to excess weight, defined as high BMI, was considerably underestimated. The PAFs attributable to WC and WHR were consistent and much higher, underlining the importance of efforts to limit and overcome the obesity epidemic in CRC prevention.

Adiposity and risks of gastrointestinal cancers: A 10-year prospective study of 0.5 million Chinese adults

Associations of adiposity with risks of oesophageal squamous cell carcinoma (ESCC) and non-cardia stomach cancer, both prevalent in China, are still inconclusive. While adiposity is an established risk factor for colorectal cancer, the relevance of fat-free mass and early-adulthood adiposity remains to be explored. The prospective China Kadoorie Biobank study included 0.5 million adults (aged 30-79 years) from 10 areas in China. Participants' body size and composition were measured at baseline and at resurveys (amongst a subset). After >10 years of follow-up, 2350, 3345 and 3059 incident cases of oesophageal (EC), stomach (SC) and colorectal (CRC) cancers were recorded, respectively. Cox regression was used to estimate hazard ratios (HRs) for these cancers in relation to different adiposity traits. General and central adiposity were inversely associated with EC (primarily ESCC) risk, with HRs of 0.81 (95% CI 0.77-0.85), 0.76 (0.72-0.81) and 0.87 (0.83-0.92) per SD increase in usual levels of BMI, body fat percentage (BF%) and waist circumference (WC), respectively. Adiposity was also inversely associated with SC risk [HR = 0.79 (0.75-0.83) and 0.88 (0.84-0.92) per SD increase in usual BF% and WC], with heterogeneity by cardia and non-cardia subsites, and positively associated with CRC [HR = 1.09 (1.03-1.15) and 1.17 (1.12-1.22) per SD higher usual BF% and WC]. Fat-free mass was inversely associated with EC [HR = 0.93 (0.89-0.98) per SD increase] but positively associated with CRC [1.09 (1.04-1.14)], while BMI at age 25 was positively associated with all three cancers. After mutual adjustment, general adiposity remained inversely associated with EC and SC, while central adiposity remained positively associated with CRC.

Impact of overweight on patients undergoing laparoscopic pancreaticoduodenectomy: analysis of surgical outcomes in a high-volume center

BACKGROUND

The feasibility and safety of laparoscopic pancreaticoduodenectomy (LPD) in overweight patients is still controversial. This study was designed to analyze the impact of overweight on surgical outcomes in patients undergoing LPD.

METHODS

Data from patients who underwent LPD between January 2018 and July 2022 were analyzed retrospectively. A 1:1 propensity score-matching (PSM) analysis was performed to minimize bias between groups.

RESULTS

A total of 432 patients were enrolled, with a normal weight group (n = 241) and an overweight group (n = 191). After matching, 144 patients were enrolled in each group. The results showed that the incidence of clinically relevant postoperative pancreatic fistula (CR-POPF) and delayed gastric emptying (DGE) was significantly higher in the overweight group compared to the normal weight group (P = 0.036). However, there were no significant differences in perioperative mortality (1.4% vs. 2.1%, P = 0.652) and long-term survival outcomes between malignancy patients with different body mass index (BMI) before and after PSM (all P > 0.05).

CONCLUSIONS

It is safe and feasible for overweight patients to undergo LPD with mortality and long-term survival outcomes comparable to the normal weight group. High-quality prospective randomized controlled trials are still needed.

The global burden of colorectal cancer attributable to high body-mass index in 204 countries and territories: findings from 1990 to 2021 and predictions to 2035

Background

The association between high body-mass index (BMI) and colorectal cancer (CRC) has been confirmed and gained attention. However, a detailed understanding of the disease burden of high BMI and CRC remains lacking.

Objective

This study aimed to assess the temporal and geographical trends of CRC deaths and disability-adjusted life years (DALYs) caused by high BMI globally from 1990 to 2021, providing effective guidance for developing prevention and treatment strategies.

Methods

We used data from the 2021 Global Burden of Disease study to assess the global, regional, and national Deaths, DALYs, age-standardized mortality rate (ASMR), and age-standardized DALY rates (ASDR) caused by CRC related to high BMI, and further calculated the estimated annual percentage change (EAPC). We also considered factors such as gender, age, and sociodemographic index (SDI). We explore the relationship between EAPC and ASMR/ASDR (1990) and between EAPC and SDI (2021). Further, the autoregressive integrated moving average (ARIMA) model was applied to predict the disease burden from 2022 to 2035. The risk factors were calculated by Population Attributable Fraction (PAF).

Results

In 2021, CRC caused by high BMI resulted in 99,268 deaths (95% Uncertainty Interval (UI): 42,956-157,949) and 2,364,664 DALYs (95% UI: 1,021,594-3,752,340) globally, with ASMR and ASDR being 1.17 per 100,000 population (95% UI: 0.51-1.87) and 27.33 per 100,000 population (95% UI: 11.8-43.37), respectively. The disease burden was higher in males and the elderly, with significant differences between regions and sociodemographic groups. From 1990 to 2021, the ASMR for CRC associated with high BMI revealed little change globally, while the ASDR revealed an upward trend. The burden of CRC caused by high BMI has shifted from high SDI regions to low and low-middle SDI regions. Additionally, from 2022 to 2035, ASMR and ASDR are expected to increase in males, while ASMR and ASDR in females are expected to remain relatively stable.

Conclusion

From 1990 to 2021, the number of deaths and DALYs related to high BMI-associated CRC globally, as well as ASMR and ASDR, continue to rise. We predict that ASMR and ASDR may further increase by 2035, making it crucial to take timely and targeted interventions.

Central obesity may account for most of the colorectal cancer risk linked to obesity: evidence from the UK Biobank prospective cohort

BACKGROUND

General obesity commonly represented by body mass index (BMI) is an established risk factor for colorectal cancer (CRC). However, it is unclear to what extent this association is accounted for by central obesity. We aimed to evaluate the associations between BMI, waist-to-hip ratio (WHR), and waist circumference (WC) with CRC risk and to investigate if and to what extent these associations are independent from each other.

METHODS

Data from more than 500,000 male and female participants aged 40-69, recruited in the UK Biobank study between 2006 and 2010, were analyzed. Multivariable Cox proportional hazards models were fitted and hazard ratios (HR) and their 95% confidence intervals (CI) were calculated.

RESULTS

During a median follow-up of 12.5 years, of 460,784 participants, 5,977 developed CRC. Multivariable adjusted HRs (95% CIs) per standard deviation increase of BMI, WHR, and WC were 1.10 (1.07-1.13), 1.18 (1.14-1.22), and 1.14 (1.11-1.18), respectively. After mutual adjustment, the association with CRC was substantially attenuated for BMI (1.04 (1.01-1.07)), and remained substantially stronger for WHR (1.15 (1.11-1.20)). Furthermore, WHR showed strong, statistically significant associations with CRC risk within all BMI categories, whereas associations of BMI with CRC risk were weak and not statistically significant within WHR categories. BMI was also not associated with CRC risk in women and with rectal cancer after mutual adjustment. Conversely, WHR was strongly associated with CRC risk in both sexes and with both colon and rectal cancer risk before and after adjustment for BMI. BMI and WC could not be mutually adjusted for due to their high correlation.

CONCLUSION

Central obesity is a much stronger predictor of CRC and may account for most of the CRC risk linked to obesity. Our findings also emphasize the need for incorporating measures such as WHR alongside BMI in clinical practice to improve obesity prevention and management.

Waist circumference-years and cancer risk: a prospective study of the association and comparison of predictive performance with waist circumference and body mass index

BACKGROUND

Associations of waist circumferences (WC) and body mass index (BMI) measured once or over time, with cancer incidence were studied. WC is associated with some cancers independent of BMI. Analyses of cumulative central adiposity and cancer are lacking. We investigated associations between waist circumference-years, incorporating exposure time to WC ≥ 102 cm in men or ≥88 cm in women, and cancer, and compared this with single WC or BMI.

METHODS

Serial WC measurements taken over 9 years in the prospective Atherosclerosis Risk in Communities Study (ARIC) predicted yearly WC. Cox proportional hazards regression estimated hazard ratios (HRs) of cancer incidence for waist circumference-years, WC or BMI, measured in Visit 4. Harrell's C-statistic quantified metric predictive performances.

RESULTS

10,172 participants were followed up from Visit 4 for cancer over a median 13.7 for men and 15.8 years for women. For obesity-related cancers, HRs per standard deviation waist circumference-years were 1.14 (95%CI:1.04,1.25) and 1.19 (95%CI:1.12,1.27), respectively. Differences in metric predictive performances were marginal.

DISCUSSION

This is the first study to identify positive associations between waist circumference-years and cancer. Waist circumference-years did not provide additional information on cancer risk beyond that of WC and BMI. BMI is routinely measured in clinic so it may be preferred over WC.

Diversity in gut microbiota among colorectal cancer patients: findings from a case-control study conducted at a Tunisian University Hospital

PURPOSE

Globally, colorectal cancer (CRC) is among the most prevalent cancers. One distinctive feature of colorectal cancer is its close relationship to the gut microbiota, which is a crucial component of the tumor microenvironment. Over the last ten years, research has demonstrated that colorectal cancer is accompanied with dysbiosis of gut bacteria, fungi, viruses, and Archaea, and that these alterations may be causal.

OBJECTIVES

This study aimed to evaluate the disruption of the microorganism composition in the intestine, especially bacteria and to determine their relationship with colorectal cancer.

METHODS

An evaluation system for determining colorectal cancer (CRC) risk and prognosis can be established more easily with the help of accurate gut microbiota profiling. Stool samples from 14 CRC patients and 13 controls were collected and the flora relative abundance was measured using targeted quantitative PCR (qPCR) assays to evaluate diagnostic potential of selected biomarkers: Streptococcus gallolyticus and Enterococcus faecalis. Culture and MALDI-TOF mass spectrometry were coupled to identify the gut microbiota in both colorectal cancer and control groups.

RESULTS

Compared with controls, the gut microbiota of CRC patients showed an increase in the abundance of Enterococcus, Fusobacterium and Streptococcus. At the species level, the CRC enriched bacterium including Escherichia coli, Enterococcus faecalis, Fusobacterium nucleatum, Streptococcus gallolyticus, Flavoni fractorplautii and Eggerthella lenta acted as promising biomarkers for early detection of CRC.

CONCLUSION

This study highlights the potential of gut microbiota biomarkers as a promising non-invasive tool for the accurate detection and distinction of individuals with CRC.

A Systematic Review of the Impact of Dietary and Lifestyle Factors on Colorectal Cancer Prevention in Gulf Cooperation Council Countries

Colorectal cancer (CRC) remains a significant health burden in the Gulf Cooperation Council (GCC) countries, necessitating a deeper understanding of modifiable risk factors. Thus, the aim of the study was to evaluate the impact of dietary and lifestyle factors on the prevention of CRC in GCC countries. Studies were identified through electronic searches and reviewed based on relevant keywords. Databases searched included Ovid's MEDLINE, EMBASE, Google Scholar, and Web of Science, covering titles and abstracts published between January 1, 2000 and July 25, 2024. The search strategy encompassed four thematic areas: "colorectal cancer," "adults above 18," "risk factors," and "GCC countries." The primary focus was on dietary and lifestyle factors. Two reviewers screened titles and abstracts to determine whether the inclusion criteria were met. A total of 1,883 records were identified across these databases. After removing 513 duplicate records, 1,370 records were screened based on titles and abstracts. Of these, 1,284 records were excluded, leaving 86 full-text articles for assessment. Eight studies were ultimately included in the final systematic review, consisting of seven case-control studies and one cross-sectional study. In GCC countries, a diet rich in fruits, vegetables, and fiber has shown protective effects against CRC, while high red meat and refined carbohydrate intake may increase risk. Regular physical activity reduces CRC risk, though the impact of smoking remains inconclusive. Evidence regarding dairy products is contradictory. There is a shortage of high-quality longitudinal studies, highlighting gaps in current research and underscoring the need for larger studies with consistent methodologies.

Body Mass Index, Height and Head and Neck Cancer Risk: the Japan Public Health Center-based Prospective Study

BACKGROUND

Although both a lower and a higher body mass index (BMI) are reportedly associated with head and neck cancer (HNC), reports from Asia are scarce. Moreover, evidence regarding the association between height and HNC is limited.

METHODS

We investigated associations between BMI, height, and the incidence of HNC among 102,668 participants (49,029 men and 53,639 women) aged 40-69 years in the Japan Public Health Center-based Prospective Study. We followed participants from 1990 to 2013. We conducted a Cox proportional hazards regression analysis, which included adjustment for potential confounders such as smoking status. Baseline weight and height information were self-reported.

RESULTS

Over an average follow-up of 18.7 years, 311 HNC cases were newly diagnosed. Lower BMI was significantly associated with HNC, with hazard ratios [HR] of 2.75 (95% confidence interval [CI]: 1.63-4.64) for <18.5 kg/m2 and 1.63 (95% CI=1.15-2.30) for 18.5-20.9 kg/m2 compared to 23-24.9 kg/m2. Increased risk was suggested for higher BMI, with an HR of 1.30 (95%CI=0.84-2.00) for ≥27.5 kg/m2. This trend was also observed in quadratic models. Results were similar among never smokers. Meanwhile, only lower BMI showed a strong association with HNC risk among former and current smokers (HR: 3.09, 95%CI: 1.54-6.20 for <18.5 kg/m2 compared to 23 to 24.9 kg/m2). Height showed no association with HNC.

CONCLUSIONS

Lower BMI was significantly associated with HNC risk, while increased HNC risk was suggested in higher BMI among never smokers. Among former and current smokers, only lower BMI was associated with HNC risk.

Fasting hyperglycaemia and fatty liver drive colorectal cancer: a retrospective analysis in 1145 patients

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) represents the hepatic manifestation of increased adiposopathy, whose pathogenetic features have been proposed as tumourigenic triggers for colorectal cancer (CRC). We aim to identify specific metabolic signatures involved in CRC development that may be used as non-invasive biomarkers, paving the way for specific and personalized strategies of CRC prevention and early detection.

METHODS

We retrospectively assessed CRC onset during a time frame of 8 years in a cohort of 1145 out-patients individuals who had previously been evaluated for Metabolic Syndrome.

RESULTS

28 patients developed CRC. No association between CRC development and visceral and general obesity was detected, while baseline fasting plasma glucose (FPG) and non-invasive liver fibrosis scores were significantly higher in patients with CRC, compared to those who did not develop cancer. Liver steatosis and MASLD were more frequently diagnosed in patients who developed CRC compared to no cancer developers. Canonical correlations among metabolic biomarkers were not present in CRC developers, differently from no cancer group. In ROC analysis, FPG and non-invasive scores also showed good sensitivity and specificity in predicting colon cancer. We then calculated ORs for metabolic biomarkers, finding that higher FPG and non-invasive scores were associated with an increased risk of developing CRC.

CONCLUSION

MASLD and increased FPG may play a role in the clinical background of CRC, bringing to light the fascinating possibility of a reversed gut-liver axis communication in the pathogenesis of CRC. Thus, the use of non-invasive scores of fatty liver may be helpful to predict the risk of CRC and serve as novel prognostic factors for prevention and therapeutic strategies.

Effect of body mass index on survival in patients with metastatic colorectal cancer receiving chemotherapy plus bevacizumab: a systematic review and meta-analysis

Aim

This systematic review and meta-analysis was to evaluate the relationship between body mass index (BMI) and the clinical outcomes in patients with metastatic colorectal cancer (mCRC) undergoing treatment with bevacizumab plus chemotherapy.

Methods

The search for relevant literature was conducted across PubMed, Embase, Cochrane Library, and Web of Science, with the final search date being October 4, 2023. We utilized the weighted mean differences (WMDs), risk ratios (RRs), or Hazard ratios (HRs) as the metric for effect sizes, which were accompanied by 95% confidence intervals (CIs).

Results

A total of 9 studies were included for analysis. The results indicated that non-obese patients with mCRC undergoing treatment with bevacizumab experienced a reduced overall survival (OS) at the six-month compared to their obese counterparts (RR: 0.97, 95% CI: 0.94 to 1.00, p = 0.047). Furthermore, no significant differences in one-year, two-year, and five-year OS, as well as PFS and median OS, were observed between obese and non-obese mCRC patients undergoing treatment with bevacizumab plus chemotherapy.

Conclusion

These findings suggest that obesity may play a role in the short-term OS of patients with mCRC undergoing bevacizumab treatment. The clinical implications of these findings underscore the importance of considering patients' BMI in the context of mCRC care. This study may also help guide personalized treatment strategies and further research into the interplay between obesity, treatment efficacy, and patient survival in mCRC. However, further investigation is warranted to substantiate the findings of this study.

Allometric versus traditional body-shape indices and risk of colorectal cancer: a Mendelian randomization analysis

BACKGROUND

Traditional body-shape indices such as Waist Circumference (WC), Hip Circumference (HC), and Waist-to-Hip Ratio (WHR) are associated with colorectal cancer (CRC) risk, but are correlated with Body Mass Index (BMI), and adjustment for BMI introduces a strong correlation with height. Thus, new allometric indices have been developed, namely A Body Shape Index (ABSI), Hip Index (HI), and Waist-to-Hip Index (WHI), which are uncorrelated with weight and height; these have also been associated with CRC risk in observational studies, but information from Mendelian randomization (MR) studies is missing.

METHODS

We used two-sample MR to examine potential causal cancer site- and sex-specific associations of the genetically-predicted allometric body-shape indices with CRC risk, and compared them with BMI-adjusted traditional body-shape indices, and BMI. Data were obtained from UK Biobank and the GIANT consortium, and from GECCO, CORECT and CCFR consortia.

RESULTS

WHI was positively associated with CRC in men (OR per SD: 1.20, 95% CI: 1.03-1.39) and in women (1.15, 1.06-1.24), and similarly for colon and rectal cancer. ABSI was positively associated with colon and rectal cancer in men (1.27, 1.03-1.57; and 1.40, 1.10-1.77, respectively), and with colon cancer in women (1.20, 1.07-1.35). There was little evidence for association between HI and colon or rectal cancer. The BMI-adjusted WHR and HC showed similar associations to WHI and HI, whereas WC showed similar associations to ABSI only in women.

CONCLUSIONS

This large MR study provides strong evidence for a potential causal positive association of the allometric indices ABSI and WHI with CRC in both sexes, thus establishing the association between abdominal fat and CRC without the limitations of the traditional waist size indices and independently of BMI. Among the BMI-adjusted traditional indices, WHR and HC provided equivalent associations with WHI and HI, while differences were observed between WC and ABSI.

Dietary, addictive and habitual factors, and risk of colorectal cancer

BACKGROUND

In Pakistan, the incidence of colorectal cancer (CRC) has sharply increased in recent years. Although several studies have reported global risk factors for CRC, no study has been conducted in Khyber Pakhtunkhwa (KPK), Pakistan, to investigate the risk factors associated with the increased CRC burden in this population.

OBJECTIVES

Therefore, we conducted a clinical survey using a case-control study design to explore the risk factors associatd with CRC.

METHODS

In the present study, one control was enrolled for each case. Both cases and controls were asked to complete a questionnaire to gather data. We analyzed all data using SPSS.

RESULTS

Our study found that certain dietary factors, such as consuming fast food (OR: 3.0; P = 0.0001) and reusing ghee (OR: 2.45; P = 0.0001) and oil (OR: 4.30; P = 0.0001), increase the risk of CRC. Additionally, use of tobacco products like smoking cigarettes (OR: 1.91; P = 0.0001) and using snuff (OR: 3.72; P = 0.0001) significantly increases the risk of CRC. Certain habitual factors, including binge eating (OR: 2.42; P = 0.0001) and spending excessive time watching TV (OR: 1.98; P = 0.0001), also increase the odds of developing CRC. However, our study also identified some protective factors against CRC, such as consuming vegetables (OR: .41; P = 0.0001), developing healthy eating habits (OR: .61; P = 0.0001), and maintaining regular sleeping patterns (OR: .45; P = 0.0001).

CONCLUSION

Given these findings, targeted health education is necessary to prevent the increase in CRC in this area. We also recommend developing and enforcing appropriate control guidelines for cancer risk factors to curb the incidence of CRC.

New Horizons: Epidemiology of Obesity, Diabetes Mellitus, and Cancer Prognosis

The global prevalence of obesity and diabetes mellitus has increased in parallel with increasing cancer incidence, due to environmental and lifestyle factors and population aging. Metabolic diseases are associated with increased cancer risk, so a growing number of patients with cancer have coexistent obesity and/or diabetes mellitus. In this narrative review, we highlight recent evidence on the clinical impact of obesity and diabetes mellitus on the prognosis of prostate, breast, and colorectal cancer, and provide an overview of the underlying mechanisms. There is evidence that obesity is associated with increased risk of recurrence, and all-cause and cancer-specific mortality among adults with prostate, breast, and colorectal cancer. Diabetes mellitus is associated with increased all-cause and cancer-specific mortality for these 3 cancers, beyond any impact of obesity. Evidence also suggests increased risk of colorectal cancer recurrence in patients with diabetes mellitus. The underlying mechanisms are multifactorial and likely include hormonal imbalances and chronic inflammation that promote cancer cell growth. Obesity and diabetes mellitus are associated with increased risk of complications and side effects of cancer treatment. Associated comorbidities such as impaired kidney function, cardiovascular disease, and neuropathies may preclude the use of guideline cancer treatment and are competing causes of death. Cancer patients with metabolic diseases require a designated clinical program and a multidisciplinary approach involving oncologists, endocrinologists, surgeons, nutritionists, and physiotherapists, to ensure coordinated and optimized patient care.

Adult Height and Risk of Colorectal Cancer: A Pooled Analysis of 10 Population-based Cohort Studies in Japan

BACKGROUND

While tall stature has been linked to an increase in the risk of colorectal cancer (CRC), its association with cancer in the colorectum and its subsites remains unclear among Asians.

METHODS

We conducted a pooled analysis of 10 population-based cohort studies among adults in Japan. Each study estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for CRC incidence associated with adult height were estimated using Cox proportional hazards regression with adjustment of the same set of covariates were then pooled to estimate summary HRs incidence using random-effect models.

RESULTS

We identified 9,470 CRC incidences among 390,063 participants during 5,672,930 person-years of follow-up. Men and women with tall stature had a higher risk of CRC and colon cancer. HRs for CRC, colon cancer, and distal colon cancer for the highest versus lowest height categories were 1.23 (95% CI, 1.07-1.40), 1.22 (95% CI, 1.09-1.36), and 1.27 (95% CI, 1.08-1.49), respectively, in men and 1.21 (95% CI, 1.09-1.35), 1.23 (95% CI, 1.08-1.40), and 1.35 (95% CI, 1.003-1.81), respectively, in women. The association with proximal colon cancer and rectal cancer was less evident in both sexes.

CONCLUSION

This pooled analysis confirms the link between tall stature and a higher risk of CRC and colon cancer (especially distal colon) among the Japanese and adds evidence to support the use of adult height to identify those at a higher risk of CRC.

The underestimated impact of excess body weight on colorectal cancer risk: Evidence from the UK Biobank cohort

BACKGROUND

The association between excess weight and colorectal cancer (CRC) risk may have been underestimated due to potential weight loss during pre-clinical sojourn time of CRC. We aimed to investigate this association and the corresponding population attributable fraction (PAF), accounting for prediagnostic weight loss.

METHODS

Data from the UK Biobank prospective cohort were used. Multivariable adjusted hazard ratios (HR) and their 95% confidence intervals (CI) for various periods of follow-up and the corresponding PAF of excess weight were calculated.

RESULTS

During a median of 10.0 years of follow-up, of 453,049 participants, 4794 developed CRC. The excess weight-CRC association became substantially stronger with including increasing lengths of follow-up in the analyses and further excluding the initial years of follow-up. HRs (95% CIs) for overweight and obesity were 1.06 (0.97-1.16) and 1.14 (1.03-1.26) after 7 years of follow-up, 1.13 (1.05-1.21) and 1.23 (1.14-1.33) when including complete follow-up length, and 1.26 (1.12-1.43) and 1.42 (1.24-1.63) when excluding the initial 7 years of follow-up. The corresponding PAFs of excess weight were estimated as 6.8%, 11.3%, and 19.0%, respectively.

CONCLUSIONS

Comprehensive consideration of the potential effect of prediagnostic weight loss discloses a much stronger impact of excess body weight on CRC risk than previously assumed.

[Obesity and Colorectal Cancer]

The prevalence of obesity has increased significantly worldwide, and this trend is likely to continue in the coming years. There is substantial evidence that obesity plays a crucial role in the development of colorectal cancer. Epidemiological data have consistently demonstrated a correlation between obesity and colorectal cancer. Insulin resistance, hyperinsulinemia, chronic inflammation, altered levels of growth factors, adipocytokines, and various hormones are plausible biological mechanisms. In addition, obesity has been shown to have an impact on recurrence, treatment success, and overall survival. There are some reports, although the evidence is not conclusive, that weight loss and lifestyle changes such as dietary modification and physical activity can reduce the risk of colorectal cancer. The understanding that obesity is a potentially modifiable risk factor that can affect the incidence and prognosis of colorectal cancer is crucial knowledge that can have an impact on the prevention and treatment of the condition.

The effect of FTO gene rs9939609 polymorphism on the association between colorectal cancer and different types of dietary fat intake: a case-control study

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers in the world. Some dietary factors such as fat intake have been identified as the risk factors for CRC. This study aimed to investigate the effect of fat mass and obesity-associated (FTO) gene rs9939609 polymorphism on the association between CRC and different types of dietary fats.

METHODS

This case-control study was performed on 135 CRC cases and 294 healthy controls in Tehran, Iran. Data on demographic factors, anthropometric measurements, physical activity, the intake of different types of dietary fats, and FTO gene rs9939609 polymorphism was collected from all participants. The association between cancer and dietary fat intake in individuals with different FTO genotypes was assessed using different models of logistic regression.

RESULTS

Oleic acid intake was higher in the case group compared to the control group in both people with TT (7.2±3.46 vs. 5.83±3.06 g/d, P=0.02) and AA/AT genotypes (8.7±6.23 vs. 5.57 ±3.2 g/d, P<0.001). Among carriers of AA/AT genotypes of FTO rs9939609 polymorphism, a positive association was found between CRC and higher intakes of oleic acid (OR=1.12, CI95% 1.03-1.21, P=0.01) and cholesterol (OR=1.01, CI95% 1.00-1.02; P=0.01) after adjusting for age, sex, physical activity, alcohol use, smoking, calorie intake, and body mass index.

CONCLUSION

Higher intakes of cholesterol and oleic acid were associated with a higher risk of CRC in FTO-risk allele carriers. The association of CRC and dietary fat may be influenced by the FTO genotype. Further longitudinal studies are warranted to confirm these findings.

Vitamin D Supplementation and Adherence to World Cancer Research Fund (WCRF) Diet Recommendations for Colorectal Cancer Prevention: A Nested Prospective Cohort Study of a Phase II Randomized Trial

Vitamin D and a healthy diet, based on World Cancer Research Fund (WCRF) recommendations, are considered key elements for colorectal cancer (CRC) prevention. In a CRC case-control study, we observed that CRC cases were often significantly Vitamin D deficient while subjects following WCRF recommendations significantly decreased their risk of developing CRC. We conducted a randomized phase-II trial (EudraCT number-2015-000467-14) where 74 CRC patients showed differences in response to Vitamin D supplementation, 2000 IU in average per day, according to gender and microbiota. The aim of this nested study is to correlate Vitamin D (supplementation, serum level and receptor polymorphisms), circulating biomarkers, and events (polyp/adenoma, CRC relapse and other cancers) in concomitant to WCRF recommendation adherence. Vitamin D supplementation did not modulate circulating biomarkers or follow-up events. FokI and TaqI VDR were associated with 25-hydroxyvitamin D (25OHD) levels. Patients following the WCRF recommendations had significantly lower leptin, significantly lower IL-6 (only in females), and significantly lower risk of events (HR = 0.41, 95%CI: 0.18-0.92; p = 0.03; median follow-up 2.6 years). Interestingly, no WCRF adherents had significantly more events if they were in the placebo (p < 0.0001), whereas no influence of WCRF was observed in the Vitamin D arm. While one-year Vitamin D supplementation might be too short to show significant preventive activity, a healthy diet and lifestyle should be the first step for preventive programs.

The association between the body roundness index and the risk of colorectal cancer: a cross-sectional study

BACKGROUND

Colorectal cancer (CRC), has a link between obesity, especially visceral fat. The body roundness index (BRI) can more accurately assess body fat and visceral fat levels. It is, however, unknown whether BRI is associated with CRC risk.

METHODS

53,766 participants were enrolled from the National Health and Nutrition Examination Survey (NHANES). Analysing the corelation between BRI and CRC risk was performed using logistic regression. Stratified analyses revealed the association based on the population type. Receiver operating characteristic curve (ROC) was performed for predicting CRC risk using different anthropometric indices.

RESULTS

The risk of CRC mounting apparently with elevated BRI for participants with CRC compared to normal participants (P-trend < 0.001). The association persisted even after adjusting for all covariates (P-trend = 0.017). In stratified analyses, CRC risk increased with increasing BRI, especially among those who were inactive (OR (95% CI): Q3 3.761 (2.139, 6.610), P < 0.05, Q4 5.972 (3.347, 8.470), P < 0.01), overweight (OR (95% CI): Q3 2.573 (1.012, 7.431), P < 0.05, Q4 3.318 (1.221, 9.020), P < 0.05) or obese (OR (95% CI): Q3 3.889 (1.829, 8.266), P < 0.001, Q4 4.920 (2.349, 10.308), P < 0.001). ROC curve showed that BRI had a better ability in forecasting the risk of CRC than other anthropometric indices such as body weight etc. (all P < 0.05).

CONCLUSIONS

CRC risk and BRI have a positive and significant relationship, particularly in inactive participants with BMI ≥ 25 kg/m². It is hoped that these results will raise awareness of the importance of reducing visceral fat deposition.

Association of Overweight, Obesity, and Recent Weight Loss With Colorectal Cancer Risk

Importance

Overweight and obesity, conditions with rising prevalence in many countries, are associated with increased colorectal cancer (CRC) risk. However, many patients with CRC lose weight before diagnosis, which may lead the association to be underestimated.

Objective

To evaluate the association of body mass index (BMI) and weight change with CRC risk when considering BMI at different time frames, with the intention to account for prediagnostic weight loss.

Design, Setting, and Participants

This population-based case-control study was conducted in southwestern Germany between 2003 and 2021. Cases with a first diagnosis of CRC and controls (frequency matched by age, sex, and county) with comprehensive risk factor information and self-reported weight at different time points were included. Data were analyzed between October 2022 and March 2023.

Exposure

BMI and weight change at different time frames before the time of diagnosis (cases) or recruitment (controls).

Main Outcomes and Measures

Association of BMI and weight change at various points in time before and up to diagnosis with CRC, assessed by multivariable logistic regression with comprehensive confounder adjustment.

Results

A total of 11 887 participants (6434 CRC cases, 5453 controls; median [IQR] age, 69 [61-77] years; 7173 male [60.3%]) were included. At the time of diagnosis, 3998 cases (62.1%) and 3601 controls (66.0%) were overweight or obese, suggesting an inverse association between excess weight and CRC risk. Conversely, we found significant positive associations of overweight (adjusted odds ratio [aOR], 1.27; 95% CI, 1.03-1.56), obesity (aOR, 2.09; 95% CI, 1.61-2.70), and a 5-unit increase in BMI (aOR, 1.35; 95% CI, 1.21-1.50) with CRC risk when using BMI measured 8 to 10 years before diagnosis. High BMI as a risk factor for CRC was increased as earlier periods before diagnosis were examined, with the association being particularly pronounced using BMI at least 8 years before diagnosis. An opposite trend was found for the association of weight loss (at or exceeding 2 kg) with CRC, with the greatest effect sizes occurring for weight loss within 2 years before diagnosis (aOR, 7.52; 95% CI, 5.61-10.09), and gradually decreased for earlier intervals.

Conclusions and Relevance

In this population-based case-control study, accounting for substantial prediagnostic weight loss further highlighted the association of overweight and obesity with CRC risk.

Excess body weight: Novel insights into its roles in obesity comorbidities

Excess body weight is a global health problem due to sedentary lifestyle and unhealthy diet, affecting 2 billion population worldwide. Obesity is a major risk factor for metabolic diseases. Notably, the metabolic risk of obesity largely depends on body weight distribution, of which visceral adipose tissues but not subcutaneous fats are closely associated with obesity comorbidities, including type 2 diabetes, non-alcoholic fatty liver disease, cardiovascular disease and certain types of cancer. Latest multi-omics and mechanistical studies reported the crucial involvement of genetic and epigenetic alterations, adipokines dysregulation, immunity changes, imbalance of white and brown adipose tissues, and gut microbial dysbiosis in mediating the pathogenic association between visceral adipose tissues and comorbidities. In this review, we explore the epidemiology of excess body weight and the up-to-date mechanism of how excess body weight and obesity lead to chronic complications. We also examine the utilization of visceral fat measurement as an accurate clinical parameter for risk assessment in healthy individuals and clinical outcome prediction in obese subjects. In addition, current approaches for the prevention and treatment of excess body weight and its related metabolic comorbidities are further discussed. DATA AVAILABILITY: No data was used for the research described in the article.

Circulating amino acid levels and colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition and UK Biobank cohorts

BACKGROUND

Amino acid metabolism is dysregulated in colorectal cancer patients; however, it is not clear whether pre-diagnostic levels of amino acids are associated with subsequent risk of colorectal cancer. We investigated circulating levels of amino acids in relation to colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) and UK Biobank cohorts.

METHODS

Concentrations of 13-21 amino acids were determined in baseline fasting plasma or serum samples in 654 incident colorectal cancer cases and 654 matched controls in EPIC. Amino acids associated with colorectal cancer risk following adjustment for the false discovery rate (FDR) were then tested for associations in the UK Biobank, for which measurements of 9 amino acids were available in 111,323 participants, of which 1221 were incident colorectal cancer cases.

RESULTS

Histidine levels were inversely associated with colorectal cancer risk in EPIC (odds ratio [OR] 0.80 per standard deviation [SD], 95% confidence interval [CI] 0.69-0.92, FDR P-value=0.03) and in UK Biobank (HR 0.93 per SD, 95% CI 0.87-0.99, P-value=0.03). Glutamine levels were borderline inversely associated with colorectal cancer risk in EPIC (OR 0.85 per SD, 95% CI 0.75-0.97, FDR P-value=0.08) and similarly in UK Biobank (HR 0.95, 95% CI 0.89-1.01, P=0.09) In both cohorts, associations changed only minimally when cases diagnosed within 2 or 5 years of follow-up were excluded.

CONCLUSIONS

Higher circulating levels of histidine were associated with a lower risk of colorectal cancer in two large prospective cohorts. Further research to ascertain the role of histidine metabolism and potentially that of glutamine in colorectal cancer development is warranted.

Is the association of overweight and obesity with colorectal cancer underestimated? An umbrella review of systematic reviews and meta-analyses

Although high body-mass index (BMI) is associated with increased risk of developing colorectal cancer (CRC), many CRC patients lose weight before diagnosis. BMI is often reported close to diagnosis, which may have led to underestimation or even reversal of direction of the BMI-CRC association. We aimed to assess if and to what extent potential bias from prediagnostic weight loss has been considered in available epidemiological evidence. We searched PubMed and Web of Science until May 2022 for systematic reviews and meta-analyses investigating the BMI-CRC association. Information on design aspects and results was extracted, including if and how the reviews handled prediagnostic weight loss as a potential source of bias. Additionally, we analyzed how individual cohort studies included in the latest systematic review handled the issue. Overall, 18 reviews were identified. None of them thoroughly considered or discussed prediagnostic weight loss as a potential source of bias. The majority (15/21) of cohorts included in the latest review did not exclude any initial years of follow-up from their main analysis. Although the majority of studies reported having conducted sensitivity analyses in which initial years of follow-up were excluded, results were reported very heterogeneously and mostly for additional exclusions of 1-2 years only. Where explicitly reported, effect estimates mostly increased with increasing length of exclusion. The impact of overweight and obesity on CRC risk may be larger than suggested by the existing epidemiological evidence.

Risk factors for right colon, left colon and rectal cancers differ between men and women: the population-based HUNT study in Norway

AIM

The aim of this study was to assess established risk factors for colorectal cancer (CRC) separately for right colon, left colon and rectal cancer in men and women.

METHOD

This was a prospective cohort study comparing incidental CRC cases and the general population participating in a longitudinal health study in Norway (the HUNT study).

RESULTS

Among 78 580 participants (36 825 men and 41 754 women), 1827 incidental CRCs were registered (931 men and 896 women). Among men, the risk of cancer at all locations increased with age [HR 1.46 (1.40-1.51), HR 1.32 (1.27-1.36), HR 1.30 (1.25-1.34) per 5 years for right colon, left colon and rectal cancer, respectively] and the risk of left colon cancer increased with higher body mass index [HR 1.28 (1.12-1.46) per 5 kg/m² ]. The risk of right colon cancer (RCC) increased with smoking [HR 1.07 (1.04-1.10) per 5 pack years]. Among women, the risk of cancer at all locations increased with age [HR 1.38 (1.34-1.43), HR 1.23 (1.19-1.27), HR 1.20 (1.16-1.24) per 5 years] and smoking [HR 1.07 (1.02-1.12), HR 1.07 (1.02-1.12), HR 1.10 (1.05-1.17) per 5 pack years] for right colon, left colon and rectal cancer, respectively. The risk of RCC increased with night shift work [HR 1.93 (1.22-3.05)].

CONCLUSION

The risk factors for developing CRC differ by anatomical location and sex. The relationship between risk factors and CRC may be more nuanced than previously known.

Energy balance-related factors in childhood and adolescence and risk of colorectal cancer based on KRAS, PIK3CA, and BRAF mutations and MMR status

KRAS mutations (KRAS_mut ), PIK3CA_mut , BRAF_mut , and deficient DNA mismatch repair (dMMR) have been associated with the Warburg effect. We previously reported differential associations between early-life energy balance-related factors (height, energy restriction, body mass index [BMI]) and colorectal cancer (CRC) subtypes based on the Warburg effect. We now investigated associations of early-life energy balance-related factors and the risk of CRC subgroups based on mutation and MMR status. Data from the Netherlands Cohort Study was used. KRAS_mut , PIK3CA_mut, BRAF_mut, and MMR status were available for 2349 CRC cases, and complete covariate data for 1934 cases and 3911 subcohort members. Multivariable-adjusted Cox regression was used to estimate associations of height, energy restriction proxies (exposure to Dutch Hunger Winter, Second World War, Economic Depression), and early adult BMI (age 20 years) with risk of CRC based on individual molecular features and combinations thereof (all-wild-type+MMR-proficient [pMMR]; any-mutation/dMMR). Height was positively associated with any-mutation/dMMR CRC but not all-wild-type+pMMR CRC, with the exception of rectal cancer in men, and with heterogeneity in associations observed for colon cancer in men (p-heterogeneity = 0.049) and rectal cancer in women (p-heterogeneity = 0.014). Results on early-life energy restriction proxies in relation to the risk of CRC subgroups did not show clear patterns. Early adult BMI was positively, but not significantly, associated with KRAS_mut colon cancer in men and with BRAF_mut and dMMR colon cancer in women. Our results suggest a role of KRAS_mut , PIK3CA_mut , BRAF_mut , and dMMR in the etiological pathway between height and CRC risk. KRAS_mut might potentially play a role in associations of early adult BMI with colon cancer risk in men, and BRAF_mut and dMMR in women.

Insights behind the Relationship between Colorectal Cancer and Obesity: Is Visceral Adipose Tissue the Missing Link?

Colorectal cancer (CRC) is a major health problem worldwide, with an estimated 1.9 million new cases and 915,880 deaths in 2020 alone. The etiology of CRC is complex and involves both genetic and lifestyle factors. Obesity is a major risk factor for CRC, and the mechanisms underlying this link are still unclear. However, the generalized inflammatory state of adipose tissue in obesity is thought to play a role in the association between CRC risk and development. Visceral adipose tissue (VAT) is a major source of proinflammatory cytokines and other factors that contribute to the characteristic systemic low-grade inflammation associated with obesity. VAT is also closely associated with the tumor microenvironment (TME), and recent evidence suggests that adipocytes within the TME undergo phenotypic changes that contribute to tumor progression. In this review, we aim to summarize the current evidence linking obesity and CRC, with a focus on the role of VAT in tumor etiology and progression.

Body Mass Index Trajectories Across the Adult Life Course and Pancreatic Cancer Risk

BACKGROUND

Body mass index (BMI) during adulthood has been associated with pancreatic ductal adenocarcinoma (PDAC), however, patterns of body size across the adult life course have not been studied extensively. We comprehensively evaluated the association between adiposity across adulthood and PDAC.

METHODS

We conducted a prospective analysis of 269 480 (162 735 males, 106 745 females) National Institutes of Health-AARP Diet and Health Study participants, aged 50-71 years (1995-1996) who self-reported height and weight history. Participants were followed through December 31, 2011. We examined associations between BMI (kg/m2) at ages 18, 35, 50, and 50-71 (baseline) years, their trajectories determined from latent-class trajectory modeling, and incident PDAC. Cox proportional hazard models were used to calculate multivariable adjusted hazards ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

During up to 15.2 years of follow-up, 3092 (2020 males, 1072 females) patients with incident PDAC were identified. BMI at all 4 ages were statistically significantly associated with increased PDAC (per 5-unit increase, HR = 1.09-1.13) with higher magnitude associations in males than females at ages 35 years and older (Pinteraction < .05). Four BMI trajectories were created. Compared with normal-weight maintainers, normal-to-overweight, normal-to-obese class I, and overweight-to-obese class III trajectories had hazard ratios of 1.15 (95% CI = 1.06 to 1.25), 1.39 (95% CI = 1.25 to 1.54), and 1.48 (95% CI = 1.18 to 1.87), respectively (Pinteraction by sex = .07).

CONCLUSIONS

High BMI and BMI trajectories that result in overweight or obesity during adulthood were positively associated with PDAC, with stronger associations among those with early onset adiposity and those with male sex. Avoidance of excess body weight throughout the adult life course may prevent PDAC.

Review article: obesity and colorectal cancer

BACKGROUND

Obesity is a growing global public health problem. More than half the European and North American population is overweight or obese. Colon and rectum cancers are still the second leading cause of cancer death worldwide, and epidemiological data support an association between obesity and colorectal cancers (CRCs).

AIM

To review the literature on CRC epidemiology in obese subjects, assessing the effects of obesity, including childhood or maternal obesity, on CRC, diagnosis, management, and prognosis, and discussing targeted prophylactic measures.

METHOD

We searched PubMed for obesity/overweight/metabolic syndrome and CRC. Other key words included 'staging', 'screening', 'treatment', 'weight loss', 'bariatric surgery' and 'chemotherapy'.

RESULTS

In Europe, about 11% of CRCs are attributed to overweight and obesity. Epidemiological data suggest that obesity is associated with a 30%-70% increased risk of colon cancer in men, the association being less consistent in women. Visceral fat or abdominal obesity seems to be of greater concern than subcutaneous fat obesity, and any 1 kg/m² increase in body mass index confers more risk (hazard ratio 1.03). Obesity might increase the likelihood of recurrence or mortality of the primary cancer and may affect initial management, including accurate staging. The risk maybe confounded by different factors, including lower adherence to organised CRC screening programmes. It is unclear whether bariatric surgery helps reduce rectal cancer risk.

CONCLUSIONS

Despite a growing body of evidence linking obesity to CRC, many questions remain unanswered, including whether we should screen patients with obesity earlier or propose prophylactic bariatric surgery for certain patients with obesity.

The timing of adiposity and changes in the life course on the risk of cancer

Excess body weight has been established as a risk factor for at least twelve cancer sites, though questions remain as to the timing of associations for adiposity and cancer risk throughout the life course. We conducted a narrative review summarizing existing evidence to provide insights into the complex timing relationship between adiposity and risk of seven common obesity-related cancers. We considered five types of studies, including traditional epidemiologic studies examining adiposity at different time points, studies examining weight gain in specific life phases, studies examining weight loss over a period including from bariatric surgery, life course trajectory analysis, and Mendelian randomization studies. The results showed that lifetime excess body weight is associated with increased risk of cancers of endometrium, colorectum, liver, kidney, and pancreas. Early life obesity is one of the strongest risk factors for pancreatic cancer but less directly important than adult obesity for endometrial and kidney cancer. Interestingly, heavy weight during childhood, adolescence, and early adulthood is protective against pre- and postmenopausal breast cancer and possibly advanced prostate cancer. It is apparent that preventing weight gain later in adulthood would likely reduce risk of many cancers, including postmenopausal breast cancer, endometrial cancer, colorectal cancer (especially in men), liver cancer, kidney cancer, and probably advanced prostate cancer. Furthermore, weight loss even late in life may confer benefits for cancers of breast, endometrium, colorectum, and liver among patients with obesity, as mostly demonstrated by studies of bariatric surgery. Overall, maintaining a healthy weight throughout the life course will help prevent a large number of cancers.

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

BACKGROUND

Physical activity has been associated with a lower risk of colorectal cancer in studies mainly conducted in high-income countries, while sedentary behavior has been suggested to increase CRC risk. In this study, we aimed to investigate the role of physical activity and sedentary behavior on CRC risk in the Moroccan population.

METHODS

A case-control study was conducted involving 1516 case-control pairs, matched on age, sex and center in five university hospital centers. A structured questionnaire was used to collect information on socio-demographics, lifestyle habits, family history of CRC, and non-steroidal anti-inflammatory drug (NSAID) use. Information on physical activity and sedentary behavior were collected by the Global Physical Activity Questionnaire (GPAQ). For each activity (work, household, and recreational activities), a metabolic equivalent (MET) was calculated using GPAQ recommendations. Conditional logistic regression models were used to assess the association between physical activity, sedentary behavior and the risk of overall CRC, colon cancer, and rectal cancer taking into account other CRC risk factors.

RESULTS

High level of physical activity was associated with lower risk of rectal cancer, colon cancer, and overall CRC, the adjusted odds ratios (ORa) for the highest versus the lowest level of activity were 0.67 (95% CI: 0.54-0.82), 0.77 (95% CI: 0.62-0.96), and 0.72 (95% CI: 0.62-0.83), respectively. In contrast, sedentary behavior was positively associated with rectal cancer risk (ORa=1.19, 95% CI: 1.01-1.40), but was unrelated to colon cancer risk (ORa=1.02, 95% CI: 0.87-1.20).

CONCLUSION

We found an inverse association between physical activity and CRC risk in the Moroccan population, and a positive association between sedentary behavior and rectal cancer risk. Considering that one-third of the total population studied had a sedentary lifestyle, these results may be used to improve strategies of public health suitable for Moroccan population.

Adult-Attained Height and Colorectal Cancer Risk: A Cohort Study, Systematic Review, and Meta-Analysis

BACKGROUND

The influence of anthropometric characteristics on colorectal neoplasia biology is unclear. We conducted a systematic review and meta-analysis to determine if adult-attained height is independently associated with the risk of colorectal cancer or adenoma.

METHODS

We searched MEDLINE, EMBASE, the Cochrane Library, and Web of Science from inception to August 2020 for studies on the association between adult-attained height and colorectal cancer or adenoma. The original data from the Johns Hopkins (Baltimore, MD) Colon Biofilm study was also included. The overall HR/OR of colorectal cancer/adenoma with increased height was estimated using random-effects meta-analysis.

RESULTS

We included 47 observational studies involving 280,644 colorectal cancer and 14,139 colorectal adenoma cases. Thirty-three studies reported data for colorectal cancer incidence per 10-cm increase in height; 19 yielded an HR of 1.14 [95% confidence interval (CI), 1.11-1.17; P < 0.001), and 14 engendered an OR of 1.09 (95% CI, 1.05-1.13; P < 0.001). Twenty-six studies compared colorectal cancer incidence between individuals within the highest versus the lowest height percentile; 19 indicated an HR of 1.24 (95% CI, 1.19-1.30; P < 0.001), and seven resulting in an OR of 1.07 (95% CI, 0.92-1.25; P = 0.39). Four studies reported data for assessing colorectal adenoma incidence per 10-cm increase in height, showing an overall OR of 1.06 (95% CI, 1.00-1.12; P = 0.03).

CONCLUSIONS

Greater adult attained height is associated with an increased risk of colorectal cancer and adenoma.

IMPACT

Height should be considered as a risk factor for colorectal cancer screening.

Energy balance‐related factors in childhood and adolescence and risk of colorectal cancer expressing different levels of proteins involved in the Warburg‐effect

Early‐life (childhood to adolescence) energy balance‐related factors (height, energy restriction, BMI) have been associated with adult colorectal cancer (CRC) risk. Warburg‐effect activation via PI3K/Akt‐signaling might explain this link. We investigated whether early‐life energy balance‐related factors were associated with risk of Warburg‐subtypes in CRC. We used immunohistochemistry for six proteins involved in the Warburg‐effect (LDHA, GLUT1, MCT4, PKM2, P53, and PTEN) on tissue microarrays of 2399 incident CRC cases from the prospective Netherlands Cohort Study (NLCS). Expression levels of all proteins were combined into a pathway‐based sum score and categorized into three Warburg‐subtypes (Warburg‐low/‐moderate/‐high). Multivariable Cox‐regression analyses were used to estimate associations of height, energy restriction proxies (exposure to Dutch Hunger Winter; Second World War [WWII]; Economic Depression) and adolescent BMI with Warburg‐subtypes in CRC. Height was positively associated with colon cancer in men, regardless of Warburg‐subtypes, and with Warburg‐low colon and Warburg‐moderate rectal cancer in women. Energy restriction during the Dutch Hunger Winter was inversely associated with colon cancer in men, regardless of Warburg‐subtypes. In women, energy restriction during the Hunger Winter and WWII was inversely associated with Warburg‐low colon cancer, whereas energy restriction during the Economic Depression was positively associated with Warburg‐high colon cancer. Adolescent BMI was positively associated with Warburg‐high colon cancer in men, and Warburg‐moderate rectal cancer in women. In conclusion, the Warburg‐effect seems to be involved in associations of adolescent BMI with colon cancer in men, and of energy restriction during the Economic Depression with colon cancer in women. Further research is needed to validate these results.

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.

OUP accepted manuscript

Background

The uptake of colonoscopy is low in individuals at risk of colorectal cancer (CRC). We constructed a risk-prediction score (RPS) in a large community-based sample at high risk of CRC to enable more accurate risk stratification and to motivate and increase the uptake rate of colonoscopy.

Methods

A total of 12,628 participants classified as high-risk according to positivity of immunochemical fecal occult blood tests or High-Risk Factor Questionnaire underwent colonoscopy. Logistic regression was used to derive a RPS and analysed the associations of the RPS with colorectal lesions, giving odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Of the participants, men (OR = 1.73, 95% CI = 1.58–1.90), older age (≥65 years; 1.41, 1.31–1.53), higher body mass index (≥28 kg/m²; 1.22, 1.07–1.39), ever smoking (1.47, 1.31–1.65), and weekly alcohol use (1.28, 1.09–1.52) were associated with a higher risk of colorectal lesions. We assigned 1 point to each of the above five risk factors and derived a RPS ranging from 0 to 5, with a higher score indicating a higher risk. Compared with a RPS of 0, a RPS of 1, 2, 3, and 4–5 showed a higher risk of colorectal lesions, with the OR (95% CI) being 1.50 (1.37–1.63), 2.34 (2.12–2.59), 3.58 (3.13–4.10), and 3.91 (3.00–5.10), respectively. The area under the receiver-operating characteristic curve of RPS in predicting colorectal lesions was 0.62.

Conclusions

Participants with an increase in the RPS of ≥1 point had a significantly higher risk of colorectal lesions, suggesting the urgency for measuring colonoscopy in this very high-risk group. High-risk strategies incorporating RPS may be employed to achieve a higher colonoscopy-uptake rate.

Obesity, metabolic syndrome, and cancer: pathophysiological and therapeutic associations

Overweight, obesity, and metabolic syndrome (MetS) have become epidemic conditions affecting 39%, 13%, and 20% of the population respectively. The aim of this article is to review the literature on the association of obesity and MetS with the risk of cancer. We also explore the effect of lifestyle modifications, such as diet, physical activity, and antidiabetic medications, on cancer incidence. Increased body mass index (BMI) has been associated with a multitude of site-specific cancers, reaching relative risk (RR) 1.54 [95% confidence interval (CI) 1.47-1.61] per 5 unit increase for endometrial cancer, as well as with overall cancer risk (RR 1.03, 95% CI 1.02-1.05). Central adiposity measured by waist circumference or waist-to-hip ratio has been suggested as a stronger predictor than BMI for several cancers, such as colorectal cancer. Metabolic Syndrome has been consistently and positively associated with the risk of very common cancers like colorectal (RR 1.34, 95% CI 1.24-1.44), endometrial (RR 1.62, 95% CI 1.26-2.07) and postmenopausal breast cancer (RR 2.01, 95% CI 1.55-2.60). Hyperglycemia and subsequently T2DM have been also shown to increase the risk of cancer. Nevertheless, these risk factors are modifiable and therefore implementing lifestyle modifications could prevent an important number of cancer cases. Adherence to cancer prevention guidelines, including maintaining a healthy weight, having regular physical exercise (RR 0.58-0.90 for different cite specific cancers) and following a healthy dietary pattern (RR 0.74-0.94 for different cite specific cancers) have a protective effect on the risk of cancer. The strength of this review is the presentation of the best evidence, as the data derive mainly from meta-analyses. Public health policies should focus on the modification of risk factors and future research is needed to reveal the pathophysiological links between these risk factors and cancer to develop more efficient prevention and treatment strategies.

Density of CD3+ and CD8+ Cells in the Microenvironment of Colorectal Cancer according to Prediagnostic Physical Activity

BACKGROUND

Physical activity is associated not only with a decreased risk of developing colorectal cancer but also with improved survival. One putative mechanism is the infiltration of immune cells in the tumor microenvironment. Experimental findings suggest that physical activity may mobilize immune cells to the tumor. We hypothesized that higher levels of physical activity prior to colorectal cancer diagnosis are associated with higher densities of tumor-infiltrating T-lymphocytes in colorectal cancer patients.

METHODS

The study setting was a northern Swedish population-based cohort, including 109,792 participants with prospectively collected health- and lifestyle-related data. For 592 participants who later developed colorectal cancer, archival tumor tissue samples were used to assess the density of CD3⁺ and CD8⁺ cytotoxic T cells by IHC. Odds ratios for associations between self-reported, prediagnostic recreational physical activity and immune cell infiltration were estimated by ordinal logistic regression.

RESULTS

Recreational physical activity >3 times per week was associated with a higher density of CD8⁺ T cells in the tumor front and center compared with participants reporting no recreational physical activity. Odds ratios were 2.77 (95% CI, 1.21-6.35) and 2.85 (95% CI, 1.28-6.33) for the tumor front and center, respectively, after adjustment for sex, age at diagnosis, and tumor stage. The risk estimates were consistent after additional adjustment for several potential confounders. For CD3, no clear associations were found.

CONCLUSIONS

Physical activity may promote the infiltration of CD8⁺ immune cells in the tumor microenvironment of colorectal cancer.

IMPACT

The study provides some evidence on how physical activity may alter the prognosis in colorectal cancer.

Prediction of hereditary nonpolyposis colorectal cancer using mRNA MSH2 quantitative and the correlation with nonmodifiable factor

BACKGROUND

Hereditary non-polyposis colon cancer is a dominantly inherited syndrome of colorectal cancer (CRC), with heightened risk for younger population. Previous studies link its susceptibility to the DNA sequence polymorphism along with Amsterdam and Bethesda criteria. However, those fail in term of applicability.

AIM

To determine a clear cut-off of MSH2 gene expression for CRC heredity grouping factor. Further, the study also aims to examine the association of risk factors to the CRC heredity.

METHODS

The cross-sectional study observed 71 respondents from May 2018 to December 2019 in determining the CRC hereditary status through MSH2 mRNA expression using reverse transcription-polymerase chain reaction and the disease’s risk factors. Data were analyzed through Chi-Square, Fischer exact, t-test, Mann-Whitney, and multiple logistics.

RESULTS

There are significant differences of MSH2 within CRC group among tissue and blood; yet, negative for significance between groups. Through the blood gene expression fifth percentile, the hereditary CRC cut-off is 11059 fc, dividing the 40 CRC respondents to 32.5% with hereditary CRC. Significant risk factors include age, family history, and staging. Nonetheless, after multivariate control, age is just a confounder. Further, the study develops a probability equation with area under the curve 82.2%.

CONCLUSION

Numerous factors have significant relations to heredity of CRC patients. However, true important factors are staging and family history, while age and others are confounders. The study also established a definite cut-off point for heredity CRC based on mRNA MSH2 expression, 11059 fc. These findings shall act as concrete foundations on further risk factors and/or genetical CRC future studies.

Prediction of hereditary nonpolyposis colorectal cancer using mRNA MSH2 quantitative and the correlation with nonmodifiable factor

BACKGROUND

Hereditary non-polyposis colon cancer is a dominantly inherited syndrome of colorectal cancer (CRC), with heightened risk for younger population. Previous studies link its susceptibility to the DNA sequence polymorphism along with Amsterdam and Bethesda criteria. However, those fail in term of applicability.

AIM

To determine a clear cut-off of MSH2 gene expression for CRC heredity grouping factor. Further, the study also aims to examine the association of risk factors to the CRC heredity.

METHODS

The cross-sectional study observed 71 respondents from May 2018 to December 2019 in determining the CRC hereditary status through MSH2 mRNA expression using reverse transcription-polymerase chain reaction and the disease's risk factors. Data were analyzed through Chi-Square, Fischer exact, t-test, Mann-Whitney, and multiple logistics.

RESULTS

There are significant differences of MSH2 within CRC group among tissue and blood; yet, negative for significance between groups. Through the blood gene expression fifth percentile, the hereditary CRC cut-off is 11059 fc, dividing the 40 CRC respondents to 32.5% with hereditary CRC. Significant risk factors include age, family history, and staging. Nonetheless, after multivariate control, age is just a confounder. Further, the study develops a probability equation with area under the curve 82.2%.

CONCLUSION

Numerous factors have significant relations to heredity of CRC patients. However, true important factors are staging and family history, while age and others are confounders. The study also established a definite cut-off point for heredity CRC based on mRNA MSH2 expression, 11059 fc. These findings shall act as concrete foundations on further risk factors and/or genetical CRC future studies.

Time trends in colorectal cancer incidence in four regions of Latin America: 1983-2012

This study aimed to assess time trends in colorectal cancer incidence from 1983 to 2012 in Latin America. This was an ecological time-series study whose population consisted of individuals aged 20 years or older diagnosed with colorectal cancer. Data from population-based cancer registries in Cali (Colombia), Costa Rica, Goiânia (Brazil), and Quito (Ecuador), were used for rates estimation, while time trends estimations were proceeded by the Joinpoint Regression Program. The study showed an increase in colorectal cancer incidence in men and women in Cali (2.8% and 3.2%, respectively), Costa Rica (3.1% and 2.1%, respectively), and Quito (2.6% and 1.2%, respectively), whereas in Goiânia, only women showed an increase in colorectal cancer rates (3.3%). For colon cancer, we observed an increasing trend in incidence rates in men and women in Cali (3.1% and 2.9%, respectively), Costa Rica (3.9% and 2.8%, respectively), and Quito (2.9% and 1.8%). For rectal cancer, we observed an increasing trend in incidence in men and women in Cali (2.5% and 2.6%, respectively), Costa Rica (2.2% and 1%, respectively), and Goiânia (5.5% and 4.6%, respectively), while in Quito only men showed an upward trend (2.8%). The study found increases in colorectal cancer, colon cancer, and rectal cancer in four Latin America regions. This findings reflect lifestyle, such as dietary changes, following the economic opening, and the prevalence variations of colorectal cancer risk factors by sex and between the four studied regions. Finally, the different strategies adopted by regions for colorectal cancer diagnosis and screening seem to influence the observed variation between anatomical sites.

Association of body-shape phenotypes with imaging measures of body composition in the UK Biobank cohort: relevance to colon cancer risk

Background

Body mass index (BMI), waist and hip circumference are strongly correlated and do not reflect body composition. A Body Shape Index (ABSI) and Hip Index (HI) define waist and hip size among individuals with the same weight and height and would thus reflect body density. We examined differences in body composition between body-shape phenotypes defined with ABSI and HI and used this information to propose explanations for associations between body-shape phenotypes and colon cancer risk.

Methods

We used data from the UK Biobank Resource for 15,520 men, 16,548 women with dual-emission X-ray absorptiometry (DXA) measurements; 3997 men, 4402 women with magnetic resonance imaging (MRI) measurements; 200,289 men, 230,326 women followed-up for colon cancer. We defined body-shape phenotypes as: large-ABSI-small-HI (“apple”), small-ABSI-large-HI (“pear”), small-ABSI-small-HI (“slim”), large-ABSI-large-HI (“wide”). We evaluated differences in body composition in linear models and associations with colon cancer risk in Cox proportional hazards models adjusted for confounders and explored heterogeneity by BMI.

Results

Among individuals with the same height and weight, visceral adipose tissue (VAT) was lowest for “pear” and highest for “apple”, while abdominal subcutaneous adipose tissue (ASAT) was lowest for “slim” and highest for “wide” phenotype. In the gynoid region, differences between “apple” and “pear” phenotypes were accounted for mainly by fat mass in women but by lean mass in men. In men, lean mass was inversely associated with waist size, while the pattern of gynoid fat resembled ASAT in women. Lean and fat mass were higher for higher BMI, but not hand grip strength. Compared to normal weight “pear”, the risk of colon cancer in men (1029 cases) was higher for “apple” phenotype for normal weight (hazard ratio HR = 1.77; 95% confidence interval: 1.16–2.69) and comparably for overweight and obese, higher for “wide” phenotype for overweight (HR = 1.60; 1.14–2.24) and comparably for obese, but higher for “slim” phenotype only for obese (HR = 1.98; 1.35–2.88). Associations with colon cancer risk in women (889 cases) were weaker.

Conclusions

ABSI-by-HI body-shape phenotypes provide information for body composition. Colon cancer risk in men appears related to ASAT quantity for “slim” and “wide” but to factors determining VAT accumulation for “apple” phenotype.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08820-6.

Feasibility of Beans/Bran Enriching Nutritional Eating For Intestinal Health & Cancer Including Activity for Longevity: A Pilot Trial to Improve Healthy Lifestyles among Individuals at High Risk for Colorectal Cancer

Purpose:

Examine the feasibility and preliminary effects of a lifestyle intervention of rice bran plus navy bean supplementation, and physical activity (PA) education on intake of fiber and whole grains, and PA levels.

Design:

Randomized-controlled, single-blinded.

Setting:

Academic institution and free-living.

Subjects:

Adults >18 years, with ≥1 adenomatous polyp removed within 3 years.

Intervention:

Participants received powder and pre-prepared meals and snacks that contained either rice bran (30 g/day) plus navy bean (30 g/day), or Fibersol-2^® (10 g/day), for 12-weeks. All participants received a 1-hour (PA) education session.

Measures:

Feasibility was assessed by recruitment and retention rates, and compliance to the study foods and procedures. Three-day food logs were analyzed using Nutritionist Pro™ to estimate fiber intake, and the Automated Self-Administered 24-hour (ASA24^®) Dietary Assessment Tool calculated Healthy Eating Index (HEI) whole grain and total scores. PA was measured using an ActivPAL™ accelerometer.

Analysis:

Continuous data were summarized as median, range, and percent change from baseline to post-intervention.

Results:

N = 20 (86.9%) completed the intervention. Compliance was 92% in the rice bran plus navy bean versus 89% in Fibersol-2^®. Navy bean consumption increased from 2 g/day to 30 g/day, and rice bran from 0 g/day to 30 g/day. Fiber intake (g/day) increased by 73% versus 82%, HEI whole grain improved by 270% versus 37%, and HEI total improved by 10% versus 9.1% in rice bran plus navy bean and Fibersol-2^®, respectively. Total PA (MET-hours/day) showed minimal change for intervention (+0.04%) and control (+4%).

Conclusion:

Findings merit a larger trial of rice bran plus navy bean and PA to evaluate efficacy for dietary and cancer prevention-related outcomes.

Is the nuclear factor kappa-b (NF-κB) pathway and inflammatory status associated with colorectal cancer?

BACKGROUND

Although genetic predisposition has a role in the etiology of colorectal cancer, there are many other factors that affect its development. In this study, it was aimed to evaluate the NF-κB pathway, inflammatory status and dietary antioxidant capacity in individuals with colorectal cancer.

METHODS

The study was carried out with 40 male subjects diagnosed with colorectal cancer aged between 39-65, years and a control group of the same number of healthy men. Subjects in the case and control groups were subdivided according to body mass index (BMI), as normal (BMI 20-24.9 kg/m²) or overweight/obese (BMI ≥25 kg/m²).

RESULTS

At the end of the study, NF-κB and interleukin-22 levels were higher in the case group, but no significant difference was found between the groups. Interleukin-23 and 8-Hydroxy-2-deoxyguanosine levels in the case group classified as overweight/obese according to BMI were significantly higher than in the control group (P = 0.001 and P < 0.001, respectively). Considering diet antioxidant capacity, it was higher in individuals in the control group than in the case group. However, there was no significant difference between the groups.

CONCLUSION

Inflammatory status and reduced dietary antioxidant capacity are risk factors in the development of colorectal cancer.

A Body Shape Index (ABSI), hip index, and risk of cancer in the UK Biobank cohort

Abdominal size is associated positively with the risk of some cancers but the influence of body mass index (BMI) and gluteofemoral size is unclear because waist and hip circumference are strongly correlated with BMI. We examined associations of 33 cancers with A Body Shape Index (ABSI) and hip index (HI), which are independent of BMI by design, and compared these with waist and hip circumference, using multivariable Cox proportional hazards models in UK Biobank. During a mean follow-up of 7 years, 14,682 incident cancers were ascertained in 200,289 men and 12,965 cancers in 230,326 women. In men, ABSI was associated positively with cancers of the head and neck (hazard ratio HR = 1.14; 95% confidence interval 1.03-1.26 per one standard deviation increment), esophagus (adenocarcinoma, HR = 1.27; 1.12-1.44), gastric cardia (HR = 1.31; 1.07-1.61), colon (HR = 1.18; 1.10-1.26), rectum (HR = 1.13; 1.04-1.22), lung (adenocarcinoma, HR = 1.16; 1.03-1.30; squamous cell carcinoma [SCC], HR = 1.33; 1.17-1.52), and bladder (HR = 1.15; 1.04-1.27), while HI was associated inversely with cancers of the esophagus (adenocarcinoma, HR = 0.89; 0.79-1.00), gastric cardia (HR = 0.79; 0.65-0.96), colon (HR = 0.92; 0.86-0.98), liver (HR = 0.86; 0.75-0.98), and multiple myeloma (HR = 0.86; 0.75-1.00). In women, ABSI was associated positively with cancers of the head and neck (HR = 1.27; 1.10-1.48), esophagus (SCC, HR = 1.37; 1.07-1.76), colon (HR = 1.08; 1.01-1.16), lung (adenocarcinoma, HR = 1.17; 1.06-1.29; SCC, HR = 1.40; 1.20-1.63; small cell, HR = 1.39; 1.14-1.69), kidney (clear-cell, HR = 1.25; 1.03-1.50), and post-menopausal endometrium (HR = 1.11; 1.02-1.20), while HI was associated inversely with skin SCC (HR = 0.91; 0.83-0.99), post-menopausal kidney cancer (HR = 0.77; 0.67-0.88), and post-menopausal melanoma (HR = 0.90; 0.83-0.98). Unusually, ABSI was associated inversely with melanoma in men (HR = 0.89; 0.82-0.96) and pre-menopausal women (HR = 0.77; 0.65-0.91). Waist and hip circumference reflected associations with BMI, when examined individually, and provided biased risk estimates, when combined with BMI. In conclusion, preferential positive associations of ABSI or inverse of HI with several major cancers indicate an important role of factors determining body shape in cancer development.

Alteration of fecal microbiota by fucoxanthin results in prevention of colorectal cancer in AOM/DSS mice

Fucoxanthin (Fx), a marine carotenoid found in edible brown algae, is well known for having anticancer properties. The gut microbiota has been demonstrated as a hallmark for colorectal cancer progression in both humans and rodents. However, it remains unclear whether the gut microbiota is associated with the anticancer effect of Fx. We investigated the chemopreventive potency of Fx and its effect on gut microbiota in a mouse model of inflammation-associated colorectal cancer (by azoxymethane/dextran sulfate sodium treatment). Fx administration (30 mg/kg bw) during a 14 week period significantly inhibited the multiplicity of colorectal adenocarcinoma in mice. The number of apoptosis-like cleaved caspase-3high cells increased significantly in both colonic adenocarcinoma and mucosal crypts. Fx administration significantly suppressed Bacteroidlales (f_uc; g_uc) (0.3-fold) and Rikenellaceae (g_uc) (0.6-fold) and increased Lachnospiraceae (g_uc) (2.2-fold), compared with those of control mice. Oral administration of a fecal suspension obtained from Fx-treated mice, aimed to enhance Lachnospiraceae, suppress the number of colorectal adenocarcinomas in azoxymethane/dextran sulfate sodium-treated mice with a successful increase in Lachnospiraceae in the gut. Our findings suggested that an alteration in gut microbiota by dietary Fx might be an essential factor in the cancer chemopreventive effect of Fx in azoxymethane/dextran sulfate sodium-treated mice.

Comprehensive Assessment of Diet Quality and Risk of Precursors of Early-Onset Colorectal Cancer

BACKGROUND

The role of poor diet quality in the rising incidence of colorectal cancer (CRC) diagnosed younger than age 50 years has not been explored. Based on molecular features of early-onset CRC, early-onset adenomas are emerging surrogate endpoints.

METHODS

In a prospective cohort study (Nurses' Health Study II), we evaluated 2 empirical dietary patterns (Western and prudent) and 3 recommendation-based indexes (Dietary Approaches to Stop Hypertension [DASH], Alternative Mediterranean Diet [AMED], and Alternative Healthy Eating Index [AHEI]-2010) with risk of early-onset adenoma overall and by malignant potential (high-risk: ≥1 cm, tubulovillous or villous histology, high-grade dysplasia, or ≥3 adenomas), among 29 474 women with 1 or more lower endoscopy before age 50 years (1991-2011). Multivariable logistic regressions were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

We documented 1157 early-onset adenomas with 375 at high risk. Western diet was positively associated, whereas prudent diet, DASH, AMED, and AHEI-2010 were inversely associated with risk of early-onset adenoma. The associations were largely confined to high-risk adenomas (the highest vs lowest quintile: Western, OR = 1.67, 95% CI = 1.18 to 2.37; prudent, OR = 0.69, 95% CI = 0.48 to 0.98; DASH, OR = 0.65, 95% CI = 0.45 to 0.93; AMED, OR = 0.55, 95% CI = 0.38 to 0.79; AHEI-2010, OR = 0.71, 95% CI = 0.51 to 1.01; all Ptrend ≤ .03), driven by those identified in the distal colon and rectum (all Ptrend ≤ .04, except AMED: Ptrend = .14).

CONCLUSION

Poor diet quality was associated with an increased risk of early-onset distal and rectal adenomas of high malignant potential. These findings provide preliminary but strong support to the role of diet in early-onset CRC.

Cancer Risk in Normal Weight Individuals with Metabolic Obesity: A Narrative Review

Obesity represents one of the most significant public health challenges worldwide. Current clinical practice relies on body mass index (BMI) to define the obesity status of an individual, even though the index has long been recognized for its limitations as a measure of body fat. In normal BMI individuals, increased central adiposity has been associated with worse health outcomes, including increased risks of cardiovascular disease and metabolic disorders. The condition leading to these outcomes has been described as metabolic obesity in the normal weight (MONW). More recent evidence suggests that MONW is associated with increased risk of several obesity-related malignancies, including postmenopausal breast, endometrial, colorectal, and liver cancers. In MONW patients, the false reassurance of a normal range BMI can lead to lost opportunities for implementing preventive interventions that may benefit a substantial number of people. A growing body of literature has documented the increased risk profile of MONW individuals and demonstrated practical uses for body composition and biochemical analyses to identify this at-risk population. In this review, we survey the current literature on MONW and cancer, summarize pathophysiology and oncogenic mechanisms, highlight potential strategies for diagnosis and treatment, and suggest directions for future research.

A Dietary Intervention High in Green Leafy Vegetables Reduces Oxidative DNA Damage in Adults at Increased Risk of Colorectal Cancer: Biological Outcomes of the Randomized Controlled Meat and Three Greens (M3G) Feasibility Trial

Green leafy vegetables (GLV) may reduce the risk of red meat (RM)-induced colonic DNA damage and colorectal cancer (CRC). We previously reported the primary outcomes (feasibility) of a 12-week randomized controlled crossover trial in adults with habitual high RM and low GLV intake with body mass index (BMI) > 30 kg/m² (NCT03582306). Herein, our objective was to report a priori secondary outcomes. Participants were recruited and enrolled in 2018, stratified by gender, and randomized to two arms: immediate intervention group (IG, n = 26) or delayed intervention group (DG, n = 24). During the 4 week intervention period, participants were provided with frozen GLV and counseled to consume 1 cooked cup equivalent daily. Participants consumed their normal diet for the remaining 8 weeks. At each of four study visits, anthropometrics, stool, and blood were taken. Overall, plasma Vitamin K1 (0.50 ± 1.18 ng/mL, p < 0.001) increased, while circulating 8OHdG (−8.52 ± 19.05 ng/mL, p < 0.001), fecal 8OHdG (−6.78 ± 34.86 ng/mL, p < 0.001), and TNFα (−16.95 ± 60.82 pg/mL, p < 0.001) decreased during the GLV intervention compared to control periods. Alpha diversity of fecal microbiota and relative abundance of major taxa did not differ systematically across study periods. Further investigation of the effects of increased GLV intake on CRC risk is warranted.