Smoking-Related Risks of Colorectal Cancer by Anatomical Subsite and Sex

The association between neighborhood socioeconomic status and the risk of incidence and mortality of colorectal cancer: A systematic review and meta-analysis of 1,678,582 participants

OBJECTIVES

We conducted a systematic review and meta-analysis to evaluate the association between neighborhood socioeconomic status (n-SES) and the risk of incidence and mortality in colorectal cancer (CRC).

SETTING

A comprehensive literature search was performed using PubMed/MEDLINE, ISI Web of Science and Scopus without any limitation until October 11, 2023. Inclusion criteria consisted of observational studies in adult subjects (≥18 years) which provided data on the association between n-SES and CRC-related incidence and mortality. Relative risk (RR) and 95 % confidence interval (CI) were pooled by employing a random-effects model. We employed validated methods to assess study quality and publication bias, utilizing the Newcastle-Ottawa Scale for quality evaluation, subgroup analysis to find possible sources of heterogeneity, Egger's regression asymmetry and Begg's rank correlation tests for bias detection and sensitivity analysis.

RESULTS

Finally, 24 studies (21 cohorts and 3 cross-sectional studies) from seven different countries with 1678,582 participants were included. The analysis suggested that a significant association between lower n-SES and an increased incidence of CRC (RR=1.11; 95 % CI: 1.08, 1.14; I2=64.4 %; p<0.001; n=46). The analysis also indicated a significant association between lower n-SES and an increased risk of mortality of CRC (RR=1.21; 95 % CI: 1.16, 1.26; I2=76.4 %; p<0.001; n=23). Furthermore, subgroup analysis revealed that there was a significant association between lower n-SES and an increased risk of incidence of CRC in colon location (RR=1.06; 95 % CI: 1.02, 1.10; I2=0.0 %; p=0.001; n=8), but not rectal location. In addition, subgroup analysis for covariates adjustment suggested that body mass index, smoking, physical activity, alcohol intake, or sex adjustment may influence the relationship between n-SES and the risk of incidence and mortality in CRC.

CONCLUSION

Lower n-SES was found to be a contributing factor to increased incidence and mortality rates associated with CRC, highlighting the substantial negative impacts of lower n-SES on cancer susceptibility and health outcomes.

Epidemiology of Colorectal Cancer in Saudi Arabia: A Review

Colorectal cancer (CRC) is the second leading cause of cancer death in the world, originating from the glandular epithelial cells of the large intestine and the rectum. This article aims to review the epidemiology of CRC in Saudi Arabia, focusing on prevalence, incidence, risk factors, preventive measures, and outcomes. This narrative review utilized the PubMed database for data extraction, including freely accessible studies published in the last 15 years. Sixteen articles from different study designs were included, while awareness and non-English language studies were excluded. In 2020, the incidence and mortality rate of CRC in Saudi Arabia were 14.6% and 1.48% among all cancers, respectively. From 2006 to 2016, the number of colon cancer and rectal cancer cases increased by 8% and 7%, respectively. Risk factors for CRC in Saudi Arabia include low education level, unemployment, physical inactivity, excess weight, poor knowledge of foods rich in fiber, cigarette smoking, reduced serum vitamin D and calcium levels, and certain gene mutations. National guidelines in Saudi Arabia recommend CRC screening for all individuals above 45 years using colonoscopy, flexible sigmoidoscopy, or fecal occult blood test. The 10-year survival rate for CRC in Saudi Arabia is 44.6%. The overall 5-year survival rate for the Ministry of National Guard-Health Affairs is 52.0%. To lower the incidence and mortality of CRC, primary, secondary, and tertiary prevention are all very important. The most crucial aspect is to concentrate on primary prevention, which may involve raising public awareness of CRC risk factors and strategies for reducing or eliminating them.

Cigarettes and waterpipe use and risk of colorectal cancer in Iran: the IROPICAN study

We aimed to investigate the association between cigarettes and waterpipe use and colorectal cancer (CRC) in an Iranian population. We analyzed data from a multicenter hospital-based case-control study in Iran (IROPICAN). Data on tobacco smoking, including cigarettes, and waterpipe smoking, were collected in detail. Multivariate logistic regressions estimated the odds ratios (ORs) and 95% confidence intervals (CIs) for the association between cigarette and waterpipe smoking and CRC, accounting for confounders including age, sex, socioeconomic status, opium use, marital status, family history of cancer, red meat, fiber, body shape at age 15 and perceived physical workload, and each other of the two exposures. The study population consisted of 3215 controls and 848 cases, including 455 colon and 393 rectum cancers. We found no association between CRC and cigarette smoking (OR, 0.8; 95% CI, 0.6-1.0) or waterpipe smoking (OR, 1.1; 95% CI, 0.9-1.5). Analysis by categories of cigarette pack-year and frequency of waterpipe smoking (head-year) did not show associations. We observed an inverse association between colon cancer and cigarette smoking (OR, 0.6; 95% CI, 0.5-0.9). There was, however, no significant association by pack-year categories. Cigarette and waterpipe smoking was not associated with CRC in the Iranian population. Further studies are needed to better understand the role of waterpipe on CRC.

Colorectal Cancer: Epidemiology, Risk Factors, and Prevention

Colorectal cancer (CRC) is the third most common cancer and the second most common cause of cancer mortality worldwide. There are disparities in the epidemiology of CRC across different populations, most probably due to differences in exposure to lifestyle and environmental factors related to CRC. Prevention is the most effective method for controlling CRC. Primary prevention includes determining and avoiding modifiable risk factors (e.g., alcohol consumption, smoking, and dietary factors) as well as increasing protective factors (e.g., physical activity, aspirin). Further studies, especially randomized, controlled trials, are needed to clarify the association between CRC incidence and exposure to different risk factors or protective factors. Detection and removal of precancerous colorectal lesions is also an effective strategy for controlling CRC. Multiple factors, both at the individual and community levels (e.g., patient preferences, availability of screening modalities, costs, benefits, and adverse events), should be taken into account in designing and implementing CRC screening programs. Health policymakers should consider the best decision in identifying the starting age and selection of the most effective screening strategies for the target population. This review aims to present updated evidence on the epidemiology, risk factors, and prevention of CRC.

Metabolic Interaction Between Host and the Gut Microbiota During High-Fat Diet-Induced Colorectal Cancer

Colorectal cancer (CRC) is the second-highest cause of cancer-associated mortality among both men and women worldwide. One of the risk factors for CRC is obesity, which is correlated with a high-fat diet prevalent in Western dietary habits. The association between an obesogenic high-fat diet and CRC has been established for several decades; however, the mechanisms by which a high-fat diet increases the risk of CRC remain unclear. Recent studies indicate that gut microbiota strongly influence the pathogenesis of both high-fat diet-induced obesity and CRC. The gut microbiota is composed of hundreds of bacterial species, some of which are implicated in CRC. In particular, the expansion of facultative anaerobic Enterobacteriaceae, which is considered a microbial signature of intestinal microbiota functional imbalance (dysbiosis), is associated with both high-fat diet-induced obesity and CRC. Here, we review the interaction between the gut microbiome and its metabolic byproducts in the context of colorectal cancer (CRC) during high-fat diet-induced obesity. In addition, we will cover how a high-fat diet can drive the expansion of genotoxin-producing Escherichia coli by altering intestinal epithelial cell metabolism during gut inflammation conditions.

Dietary Patterns and Lifestyle Factors Associated with the Risk of Colorectal Cancer: A Hospital-Based Case-Control Study among Malaysians

Background

This study aimed to examine the association between dietary patterns, lifestyle factors, and colorectal cancer (CRC) risk among the Malaysian population.

Methods

We recruited 100 patients and 100 controls from two selected government hospitals. Principal component analysis was used to identify dietary patterns using a 123-item semiquantitative food frequency questionnaire. Tobacco smoking and alcohol consumption questionnaires were modified from the WHO STEPS Survey questionnaire. Physical activity levels were assessed using the revised Global Physical Activity questionnaire. Associations between dietary patterns, lifestyle factors and CRC risk were assessed using logistic regression with SPSS version 24.0.

Results

Three dietary patterns were derived from factor analysis: i) vegetables; ii) meat, seafood and processed food; and iii) grains and legumes. High vegetable diet intake was independently and significantly associated with an 81% decreased risk of CRC (odds ratio [OR]: 0.19; 95% confidence interval [CI]: 0.08, 0.46). Both recreational-related physical activity (OR: 2.04; 95% CI: 1.14, 3.64) and vigorous physical activity (OR: 2.06; 95% CI: 1.13, 3.74) are significantly associated with decreased risk of CRC. Increasing the number of cigarettes smoked (≥ 16 cigarettes) per day significantly increased the odds of developing CRC (OR: 2.58; 95% CI: 1.95, 6.75). The duration of alcohol consumption cessation was inversely associated with CRC risk (OR: 2.52; 95% CI: 2.30, 10.57).

Conclusion

The protective effects of a fruit and vegetable diet, and a healthy lifestyle can be used to develop interventions that help reduce the risk of CRC in the Malaysian population.

"We adjusted for race": now what? A systematic review of utilization and reporting of race in American Journal of Epidemiology and Epidemiology, 2020-2021

Race is a social construct, commonly used in epidemiologic research to adjust for confounding. However, adjustment of race may mask racial disparities, thereby perpetuating structural racism. We conducted a systematic review of articles published in Epidemiology and American Journal of Epidemiology between 2020 and 2021 to (1) understand how race, ethnicity, and similar social constructs were operationalized, used, and reported; and (2) characterize good and poor practices of utilization and reporting of race data on the basis of the extent to which they reveal or mask systemic racism. Original research articles were considered for full review and data extraction if race data were used in the study analysis. We extracted how race was categorized, used-as a descriptor, confounder, or for effect measure modification (EMM)-and reported if the authors discussed racial disparities and systemic bias-related mechanisms responsible for perpetuating the disparities. Of the 561 articles, 299 had race data available and 192 (34.2%) used race data in analyses. Among the 160 US-based studies, 81 different racial categorizations were used. Race was most often used as a confounder (52%), followed by effect measure modifier (33%), and descriptive variable (12%). Fewer than 1 in 4 articles (22.9%) exhibited good practices (EMM along with discussing disparities and mechanisms), 63.5% of the articles exhibited poor practices (confounding only or not discussing mechanisms), and 13.5% were considered neither poor nor good practices. We discuss implications and provide 13 recommendations for operationalization, utilization, and reporting of race in epidemiologic and public health research.

Colorectal cancer cell exosome and cytoplasmic membrane for homotypic delivery of therapeutic molecules

Colorectal cancer (CRC) is one of the most common causes of death in the world. The multi-drug resistance, especially in metastatic colorectal cancer, drives the development of new strategies that secure a positive outcome and reduce undesirable side effects. Nanotechnology has made an impact in addressing some pharmacokinetic and safety issues related to administration of free therapeutic agents. However, demands of managing complex biointerfacing require equally complex methods for introducing stimuli-responsive or targeting elements. In order to procure a more efficient solution to the overcoming of biological barriers, the physiological functions of cancer cell plasma and exosomal membranes provided the source of highly functionalized coatings. Biomimetic nanovehicles based on colorectal cancer (CRC) membranes imparted enhanced biological compatibility, immune escape and protection to diverse classes of therapeutic molecules. When loaded with therapeutic load or used as a coating for other therapeutic nanovehicles, they provide highly efficient and selective cell targeting and uptake. This review presents a detailed overview of the recent application of homotypic biomimetic nanovehicles in the management of CRC. We also address some of the current possibilities and challenges associated with the CRC membrane biomimetics.

Colorectal Cancer: From Risk Factors to Oncogenesis

Colorectal cancer is the second leading cause of cancer-related mortality worldwide. Numerous pathophysiological mechanisms, such as abnormal cell proliferation, cell differentiation, resistance to apoptosis, invasion of structures adjacent to colorectal tumor cells, and distant metastasis, are involved in colorectal carcinogenesis. These processes are initiated by the complex interaction of a number of genetic and environmental factors, including sedentary lifestyle, obesity, alcohol consumption, smoking, or gut microbiota. Despite the significant progress achieved in the diagnostic and therapeutic management of patients with colorectal cancer, there has been recently a noteworthy increase in the incidence of colorectal cancer in individuals below the age of 50 years. Early-onset colorectal cancer has a different frequency of oncogenic mutations, a higher prevalence of mucinous histology, a distinct deoxyribonucleic acid (DNA) methylation profile, a more distal location, and lower survival rates. A significant improvement in the prognosis of these patients can be achieved through the detection and removal of modifiable risk factors, along with the implementation of personalized screening strategies for individuals at high risk for this malignancy. Furthermore, gaining comprehension of the pathophysiological mechanisms by which these risk factors contribute to the process of oncogenesis may facilitate the discovery of novel therapeutic targets.

Association between smoking and colorectal cancer in Eastern Mediterranean Regional Office (EMRO): A systematic review and meta-analysis

Background

Smoking poses a significant risk for colorectal cancer (CRC), considered the third leading reason for cancer-related deaths worldwide. However, there has been limited research on the relationship between smoking and CRC in the Eastern Mediterranean Regional Office (EMRO). Therefore, a meta-analysis was conducted to combine available data and gain a comprehensive understanding of the relationship between smoking and CRC in EMRO.

Methods

Two independent researchers searched PubMed, Scopus, and Web of Science until December 2022. The included studies were checked for risk of bias administering the Newcastle-Ottawa scale. Heterogeneity was evaluated using I2 statistics and the Cochrane test. Publication bias was determined through funnel plot analysis and Egger's regression test. Additionally, a meta-regression analysis explored the impact of a country's Human Development Index (HDI) on the relationship between smoking and CRC.

Results

The final analysis included 26 studies, revealing a significant association between smoking and CRC (OR = 1.40; 95% CI: 1.11 - 1.78; P = 0.004). Moreover, smoking had a more pronounced adverse effect on CRC in countries with higher HDIs compared to those with lower HDIs (OR = 1.30; 95% CI: 0.99 - 1.71; P = 0.054).

Conclusions

Our findings underscore the importance of implementing smoking cessation programs and policies in EMRO countries, as they demonstrate a positive relationship between smoking and the risk of CRC. Furthermore, the results suggest that a country's level of human development may influence the association between smoking and CRC. Further research is needed to investigate this potential connection and develop targeted public health interventions.

Dextran-Coated Iron Oxide Nanoparticles Loaded with 5-Fluorouracil for Drug-Delivery Applications

This study aims to design and test different formulations composed of dextran-coated iron oxide nanoparticles (IONPs) loaded with 5-Fluorouracil (5-FU) with varying nanoparticle:drug ratios on colorectal cancer cells. The stable suspension of IONPs s was synthesized by the adapted co-precipitation method. The stable suspension of IONPs was mixed with a solution of dextran and 5-FU solubilized in a saline solution. The final suspensions with optimized ratios of IONP:5-FU in the final suspension were 0.5:1, 1:1, and 1.5:1. The information on the morphology and size distribution of the IONPs suspension and IONP loads with 5-FU was obtained using scanning electron microscopy (SEM). The presence of 5-FU and dextran on the surface of the IONPs was highlighted by energy-dispersive X-ray spectroscopy (EDS) studies. The determination of the surface charge of the nanoparticles in the final suspensions of IONP:5-FU was achieved by measuring the zeta potential (ζ). The hydrodynamic diameter of the resulting suspensions of IONP:5-FU was determined by dynamic light scattering (DLS). A cytocompatibility analysis was performed using Caco-2 (human epithelial colorectal adenocarcinoma) cells. In this research, our goal was to find a relationship between the formulation ratio of nanoparticles and drug, and the cellular response after exposure, as a strategy to increase the efficacy of this drug-delivery system. The nanoparticle uptake and antitumor activity, including modulation of oxidative stress, apoptosis, and proliferation biomarkers, were analyzed. The present study showed that the nanoformulation with the ratio IONP:5-FU 1.5:1 had the highest anti-tumor efficiency. Moreover, decreased MCM-2 expression in Caco-2 cells exposed to dextran-coated iron oxide nanoparticles loaded with 5-FU was demonstrated for the first time.

Spatial clustering of colorectal cancer in Malaysia

INTRODUCTION

The rise in colorectal cancer (CRC) incidence becomes a global concern. As geographical variations in the CRC incidence suggests the role of area-level determinants, the current study was designed to identify the spatial distribution pattern of CRC at the neighbourhood level in Malaysia.

METHOD

Newly diagnosed CRC cases between 2010 and 2016 in Malaysia were identified from the National Cancer Registry. Residential addresses were geocoded. Clustering analysis was subsequently performed to examine the spatial dependence between CRC cases. Differences in socio-demographic characteristics of individuals between the clusters were also compared. Identified clusters were categorized into urban and semi-rural areas based on the population background.

RESULT

Most of the 18 405 individuals included in the study were male (56%), aged between 60 and 69 years (30.3%) and only presented for care at stages 3 or 4 of the disease (71.3%). The states shown to have CRC clusters were Kedah, Penang, Perak, Selangor, Kuala Lumpur, Melaka, Johor, Kelantan, and Sarawak. The spatial autocorrelation detected a significant clustering pattern (Moran's Index 0.244, p< 0.01, Z score >2.58). CRC clusters in Penang, Selangor, Kuala Lumpur, Melaka, Johor, and Sarawak were in urbanized areas, while those in Kedah, Perak and Kelantan were in semi-rural areas.

CONCLUSION

The presence of several clusters in urbanized and semi-rural areas implied the role of ecological determinants at the neighbourhood level in Malaysia.  Such findings could be used to guide the policymakers in resource allocation and cancer control.

Colorectal Cancer-The "Parent" of Low Bowel Obstruction

Introduction: Despite the improvement of early diagnosis methods for multiple pathological entities belonging to the digestive tract, bowel obstruction determined by multiple etiologies represents an important percentage of surgical emergencies. General data: Although sometimes obstructive episodes are possible in the early stages of colorectal cancer, the most commonly installed intestinal obstruction has the significance of an advanced evolutionary stage of neoplastic disease. Development of Obstructive Mechanism: The spontaneous evolution of colorectal cancer is always burdened by complications. The most common complication is low bowel obstruction, found in approximately 20% of the cases of colorectal cancer, and it can occur either relatively abruptly, or is preceded by initially discrete premonitory symptoms, non-specific (until advanced evolutionary stages) and generally neglected or incorrectly interpreted. Success in the complex treatment of a low neoplastic obstruction is conditioned by a complete diagnosis, adequate pre-operative preparation, a surgical act adapted to the case (in one, two or three successive stages), and dynamic postoperative care. The moment of surgery should be chosen with great care and is the result of the experience of the anesthetic-surgical team. The operative act must be adapted to the case and has as its main objective the resolution of intestinal obstruction and only in a secondary way the resolution of the generating disease. Conclusions: The therapeutic measures adopted (medical-surgical) must have a dynamic character in accordance with the particular situation of the patient. Except for certain or probably benign etiologies, the possibility of colorectal neoplasia should always be considered, in low obstructions, regardless of the patient's age.

Long-term exposure to traffic noise and risk of incident colon cancer: A pooled study of eleven Nordic cohorts

Background Colon cancer incidence is rising globally, and factors pertaining to urbanization have been proposed involved in this development. Traffic noise may increase colon cancer risk by causing sleep disturbance and stress, thereby inducing known colon cancer risk-factors, e.g. obesity, diabetes, physical inactivity, and alcohol consumption, but few studies have examined this. Objectives The objective of this study was to investigate the association between traffic noise and colon cancer (all, proximal, distal) in a pooled population of 11 Nordic cohorts, totaling 155,203 persons. Methods We identified residential address history and estimated road, railway, and aircraft noise, as well as air pollution, for all addresses, using similar exposure models across cohorts. Colon cancer cases were identified through national registries. We analyzed data using Cox Proportional Hazards Models, adjusting main models for harmonized sociodemographic and lifestyle data. Results During follow-up (median 18.8 years), 2757 colon cancer cases developed. We found a hazard ratio (HR) of 1.05 (95% confidence interval (CI): 0.99-1.10) per 10-dB higher 5-year mean time-weighted road traffic noise. In sub-type analyses, the association seemed confined to distal colon cancer: HR 1.06 (95% CI: 0.98-1.14). Railway and aircraft noise was not associated with colon cancer, albeit there was some indication in sub-type analyses that railway noise may also be associated with distal colon cancer. In interaction-analyses, the association between road traffic noise and colon cancer was strongest among obese persons and those with high NO₂-exposure. Discussion A prominent study strength is the large population with harmonized data across eleven cohorts, and the complete address-history during follow-up. However, each cohort estimated noise independently, and only at the most exposed façade, which may introduce exposure misclassification. Despite this, the results of this pooled study suggest that traffic noise may be a risk factor for colon cancer, especially of distal origin.

Depression Is Associated with an Increased Risk of Subsequent Cancer Diagnosis: A Retrospective Cohort Study with 235,404 Patients

Background: Depression and cancer share common risk factors and mechanisms of disease. The current literature has not explored the effect of depression on cancer risk. We assessed the difference in cancer risk in patients with and without depression in a large cohort in Germany. Methods: We compared cancer risk and incidence in patients with and without depression aged 18 or above diagnosed between 2015 and 2018 documented in the Disease Analyzer Database. Patients from a comparator group were matched 1:1 to patients with depression based on propensity scores. Patients with previous bipolar disorder (F31), mania (F30) or schizophrenia (F20-29) and cancer diagnosis 3 years prior to index date were excluded. Analyses were stratified by cancer type, age group, and gender. Results: A total of 117,702 patients with depression were included and matched 1:1, resulting in a cohort overall of 235,404. 4.9% of patients with depression compared to 4.1% without depression received at least one cancer diagnosis over 3.9 years median follow-up. The depression group showed an 18% increase in risk for a cancer diagnosis overall, with largest increased risk in lung cancer (HR: 1.39 [1.21-1.60], p < 0.0001), cancers of the gastro-intestinal-tract (HR: 1.30 [1.15-1.46], p < 0.0001), breast (HR: 1.23 [1.12-1.35], p < 0.0001) and urinary (HR: 1.23 [1.06-1.43], p < 0.01). Similarly, the incidence of cancer diagnosis overall increased by 22% for depressed patients. IRs showed no difference across cancer types. Conclusions: Depression increased the risk for cancer diagnosis consistently independent of the comparison method used. The potential mediating factors or shared mechanisms of the disease require further investigation.

The comparison of risk factors for colorectal neoplasms at different anatomical sites

AIM

Both the clinical manifestation and molecular characteristics of colorectal cancer (CRC) vary according to the anatomical site. We explored the risk factors for four groups of colorectal neoplasms (CRN) at different anatomical sites.

METHODS

We extracted data from the database of Tianjin Colorectal Cancer Screening Program from 2010 to 2020. According to the CRN anatomical sites, patients were divided into four groups: the proximal colon group, the distal colon group, the rectum group, and the multiple colorectal sites. Binary logistic regression analysis was used to explore the differences in risk factors of CRN at different anatomical sites.

RESULTS

The numbers of patients with CRN in the proximal colon, distal colon, rectum, and multiple colorectal sites were 4023, 6920, 3657, and 7938, respectively. Male sex was associated with a higher risk from the proximal colon to the rectum. Advanced age and obesity were also significantly associated with overall colorectal CRN risk, but there were some differences between men and women. Smoking was associated with CRN risk only in the distal colon and rectum in both men and women. Frequent alcohol consumption and family history of CRC in first-degree relatives (FDRs) were associated with the risk of multisite colorectal CRN only in males.

CONCLUSIONS

We observed differences in advanced age, obesity, smoking, alcohol consumption, and family history of colorectal cancer at different anatomical sites of colorectal neoplasms. These factors vary by gender.

Colorectal cancer screening in a safety-net health system: The intersectional impact of race, ethnicity, language, and mental health

Though rates of colorectal cancer (CRC) screening continue to improve with increased advocacy and awareness, there are numerous disparities that continue to be defined within different health systems and populations. We aimed to define associations between patients' socio-demographic characteristics and CRC screening in a well-resourced safety-net health system. A retrospective review was performed from 2018 to 2019 of patients between 50 and 75-years-old who had a primary care visit within the last two years. Numerous patient characteristics were extracted from the medical record, including self-reported race, self-reported ethnicity, insurance, preferred language, severe mental health diagnoses (SMHD), and substance use disorder (SUD). Multivariate logistic regression assessed characteristics associated with CRC screening. Of 22,145 included patients, 16,065 (72.5%) underwent CRC screening. <40% of the population was White or of North American/European ethnicity and 38% had limited English proficiency. Hispanic patients had the highest screening rate while White patients had the lowest among races (78.1% vs 68.5%, respectively). White patients had higher rates of SMHD and SUD (p < 0.001). In multivariable analysis, most other races (Black, Asian, and Hispanic), ethnicities, and languages had significantly higher odds of screening, ranging from 20% to 55% higher, when White, North American/European, English-speakers are used as reference. In a well-resourced safety-net health system, patients who were non-White, non-North American/European, and non-English-speaking, had higher odds of CRC screening. This data from a unique health system may better guide screening outreach and implementation strategies in historically under-resourced communities, leading to strategies for equitable colorectal cancer screening.

Smoking and pancreatic cancer: a sex-specific analysis in the Multiethnic Cohort study

PURPOSE

To examine whether the detrimental smoking-related association with pancreatic cancer (PC) is the same for women as for men.

METHODS

We analyzed data from 192,035 participants aged 45-75 years, enrolled in the Multiethnic Cohort study (MEC) in 1993-1996. We identified PC cases via linkage to the Hawaii and California Surveillance, Epidemiology, and End Results Program cancer registries through December 2017.

RESULTS

During a mean follow-up of 19.2 years, we identified 1,936 incident PC cases. Women smokers smoked on average less than men smokers. In multivariate Cox regression models, as compared with sex-specific never smokers, current smokers had a similar elevated risk of PC for women, hazard ratio (HR) 1.49 (95% CI 1.24, 1.79) and as for men, HR 1.48 (95% CI 1.22, 1.79) (pheterogeneity: 0.79). Former smokers showed a decrease in risk of PC for men within 5 years, HR 0.74 (95% CI 0.57, 0.97) and for women within 10 years after quitting, HR 0.70 (95% CI 0.50, 0.96), compared with their sex-specific current smokers. Both sexes showed a consistent, strong, positive dose-response association with PC for the four measures (age at initiation, duration, number of cigarettes per day, number of pack-years) of smoking exposure among current smokers and an inverse association for years of quitting and age at smoking cessation among former smokers (all ptrend's < 0.001).

CONCLUSION

Although MEC women smoke on average less than their men counterparts, the smoking-related increase in PC risk and the benefits of cessation seem to be of similar magnitudes for women as for men.

Disparities in Recommendations for Colorectal Cancer Screening Among Average-Risk Individuals: An Ecobiosocial Approach

Regardless of the high global burden of colorectal cancer (CRC), the uptake of CRC screening varies across countries. This systematic review aimed to provide a picture of the disparities in recommendations for CRC screening in average-risk individuals using an ecobiosocial approach. It was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The literature search was conducted through Scopus, Web of Science, PubMed, and EBSCOHost. Full-text guidelines which were published between 2011 and 2021, along with guidelines which provided recommendations on CRC screening in average-risk individuals, were included in the review. However, guidelines focusing only on a single screening modality were excluded. Fourteen guidelines fulfilling the eligibility criteria were retained for the final review and analysis. Quality assessment of each guideline was performed using the AGREE II instrument. Disparities in guidelines identified in this review were classified into ecological (screening modalities and strategies), biological (recommended age, gender and ethnicities), and social (smoking history, socioeconomic status, and behavior) factors. In general, unstandardized practices in CRC screening for average-risk individuals are likely attributable to the inconsistent and non-specific recommendations in the literature. This review calls on stakeholders and policymakers to review the existing colorectal cancer screening practices and pursue standardization.

Colorectal Cancer: A Review of Carcinogenesis, Global Epidemiology, Current Challenges, Risk Factors, Preventive and Treatment Strategies

Colorectal cancer (CRC) is the second most deadly cancer. Global incidence and mortality are likely to be increased in the coming decades. Although the deaths associated with CRC are very high in high-income countries, the incidence and fatalities related to CRC are growing in developing countries too. CRC detected early is entirely curable by surgery and subsequent medications. However, the recurrence rate is high, and cancer drug resistance increases the treatment failure rate. Access to early diagnosis and treatment of CRC for survival is somewhat possible in developed countries. However, these facilities are rarely available in developing countries. Highlighting the current status of CRC, its development, risk factors, and management is crucial in creating public awareness. Therefore, in this review, we have comprehensively discussed the current global epidemiology, drug resistance, challenges, risk factors, and preventive and treatment strategies of CRC. Additionally, there is a brief discussion on the CRC development pathways and recommendations for preventing and treating CRC.

Exploring the Inflammatory Pathogenesis of Colorectal Cancer

Colorectal cancer is one of the most commonly diagnosed cancers worldwide. Traditionally, mechanisms of colorectal cancer formation have focused on genetic alterations including chromosomal damage and microsatellite instability. In recent years, there has been a growing body of evidence supporting the role of inflammation in colorectal cancer formation. Multiple cytokines, immune cells such T cells and macrophages, and other immune mediators have been identified in pathways leading to the initiation, growth, and metastasis of colorectal cancer. Outside the previously explored mechanisms and pathways leading to colorectal cancer, initiatives have been shifted to further study the role of inflammation in pathogenesis. Inflammatory pathways have also been linked to some traditional risk factors of colorectal cancer such as obesity, smoking and diabetes, as well as more novel associations such as the gut microbiome, the gut mycobiome and exosomes. In this review, we will explore the roles of obesity and diet, smoking, diabetes, the microbiome, the mycobiome and exosomes in colorectal cancer, with a specific focus on the underlying inflammatory and metabolic pathways involved. We will also investigate how the study of colon cancer from an inflammatory background not only creates a more holistic and inclusive understanding of this disease, but also creates unique opportunities for prevention, early diagnosis and therapy.

Impact of Allogeneic Leukocyte-Depleted Red Blood Cell Transfusion on Inflammatory Response and Blood Coagulation in Patients with Recurrence of Colon Cancer after Operation

Objective

Anemia inevitably affects the survival of cancer patients. In clinical practice, patients with anemia and decreased blood volume are treated by component blood transfusion. Through targeted blood transfusion therapy, the efficacy of blood transfusion treatment can be validly improved, which renders clinical benefits in reducing transfusion-induced adverse reactions (ARs). This research project mainly investigated the impact of allogeneic leukocyte-depleted red blood cell (LDRBC) transfusion on inflammatory response and coagulation status of patients with postoperative recurrence of colon cancer (CC).

Methods

A total of 80 patients with postoperative recurrence of CC admitted to Changzhou Second People's Hospital affiliated to Nanjing Medical University from September 2017 to December 2020 were selected as the study subjects. 36 patients with allogeneic suspended red blood cell (RBC) transfusion were used as the control group (CG), and 44 patients receiving allogeneic LDRBC transfusion served as the observation group (OG). The two groups were compared regarding alterations in pretransfusion and posttransfusion serum inflammatory factors, stress indicators and coagulation function, incidence of ARs, postoperative infection, and average incision healing time.

Results

After blood transfusion, serum tumor necrosis interleukin- (IL-) 6, IL-10, factor-α (TNF-α), and C-reactive protein (CRP) decreased in both cohorts, with lower parameters in CG (P < 0.05); the stress indexes, adrenocortical hormone (ACTH), adrenaline (AD), norepinephrine (NE), and cortisol (Cor) increased, especially in CG (P < 0.05); prothrombin time (PT), thrombin time (TT), and activated partial prothrombin time (APTT) in CG were lower than those in OG, and FIB was higher than that in OG with significant differences between two cohorts (all P < 0.05). The two groups had similar cases of lung infection and wound infection (P > 0.05), but the incision healing time was evidently shorter in OG as compared to CG (9.73 ± 1.86 vs 14.67 ± 2.39 d, P < 0.05). The total incidence of ARs was 16.7% in CG and 6.9% in OG, with no significant difference (P > 0.05).

Conclusions

In the blood transfusion treatment for patients with postoperative recurrence of CC, LDRBC transfusion renders significant clinical benefits, which can effectively improve the coagulation function of patients, reduce stress reaction, and shorten incision healing time without increasing ARs during treatment and postoperative infection rate, which is worth popularizing.

Growth Factors, PI3K/AKT/mTOR and MAPK Signaling Pathways in Colorectal Cancer Pathogenesis: Where Are We Now?

Colorectal cancer (CRC) is a predominant malignancy worldwide, being the fourth most common cause of mortality and morbidity. The CRC incidence in adolescents, young adults, and adult populations is increasing every year. In the pathogenesis of CRC, various factors are involved including diet, sedentary life, smoking, excessive alcohol consumption, obesity, gut microbiota, diabetes, and genetic mutations. The CRC tumor microenvironment (TME) involves the complex cooperation between tumoral cells with stroma, immune, and endothelial cells. Cytokines and several growth factors (GFs) will sustain CRC cell proliferation, survival, motility, and invasion. Epidermal growth factor receptor (EGFR), Insulin-like growth factor -1 receptor (IGF-1R), and Vascular Endothelial Growth Factor -A (VEGF-A) are overexpressed in various human cancers including CRC. The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) and all the three major subfamilies of the mitogen-activated protein kinase (MAPK) signaling pathways may be activated by GFs and will further play key roles in CRC development. The main aim of this review is to present the CRC incidence, risk factors, pathogenesis, and the impact of GFs during its development. Moreover, the article describes the relationship between EGF, IGF, VEGF, GFs inhibitors, PI3K/AKT/mTOR-MAPK signaling pathways, and CRC.

Effects of electronic cigarette aerosol exposure on oral and systemic health

Conventional cigarette smoke harms nearly every organ of the body and is the leading cause of death in the United States and in the world. Decades of research have associated conventional cigarette smoke with several diseases and death. Heavily marketed, electronic nicotine delivery systems such as electronic cigarettes (e-cigarettes) are available in a variety of flavors and high nicotine concentrations. In 2019, a severe lung disease outbreak linked to e-cigarette use led to several deaths, which was called electronic-cigarette or vaping product use-associated lung injury (EVALI). Even though the trend of e-cigarette use among teens continues to increase, information on the effects of e-cigarette smoke on oral and overall health are still scarce. This review discusses the possible health effects due to unregulated e-cigarette use, as well as the health effects of second-hand smoke and third-hand smoke on non-smokers.

Causal Effects of Lifetime Smoking on Breast and Colorectal Cancer Risk: Mendelian Randomization Study

BACKGROUND

Observational evidence has shown that smoking is a risk factor for breast and colorectal cancer. We used Mendelian randomization (MR) to examine causal associations between smoking and risks of breast and colorectal cancer.

METHODS

Genome-Wide Association Study summary data were used to identify genetic variants associated with lifetime amount of smoking (n = 126 variants) and ever having smoked regularly (n = 112 variants). Using two-sample MR, we examined these variants in relation to incident breast (122,977 cases/105,974 controls) and colorectal cancer (52,775 cases/45,940 controls).

RESULTS

In inverse-variance weighted models, a genetic predisposition to higher lifetime amount of smoking was positively associated with breast cancer risk [OR per 1-SD increment: 1.13; 95% confidence interval (CI): 1.00-1.26; P = 0.04]; although heterogeneity was observed. Similar associations were found for estrogen receptor-positive and estrogen receptor-negative tumors. Higher lifetime amount of smoking was positively associated with colorectal cancer (OR per 1-SD increment, 1.21; 95% CI, 1.04-1.40; P = 0.01), colon cancer (OR, 1.31; 95% CI, 1.11-1.55; P < 0.01), and rectal cancer (OR, 1.36; 95% CI, 1.07-1.73; P = 0.01). Ever having smoked regularly was not associated with risks of breast (OR, 1.01; 95% CI, 0.90-1.14; P = 0.85) or colorectal cancer (OR, 0.97; 95% CI, 0.86-1.10; P = 0.68).

CONCLUSIONS

These findings are consistent with prior observational evidence and support a causal role of higher lifetime smoking amount in the development of breast and colorectal cancer.

IMPACT

The results from this comprehensive MR analysis indicate that lifetime smoking is a causal risk factor for these common malignancies.

Risk of Second Primary Malignancies Based on the Histological Subtypes of Colorectal Cancer

Background: Previous studies have revealed an increased risk of second primary malignancies (SPMs) after colorectal cancer (CRC); however, no previous investigation has quantified differences in the risk of SPMs based on the histological subtypes of first primary CRC.

Methods: Patients diagnosed with first primary CRC between 2000 and 2011 were identified from the Surveillance, Epidemiology, and End Results cancer registries. The patients were divided into three cohorts: classical adenocarcinoma (CA), mucinous adenocarcinoma (MA), and signet-ring cell carcinoma (SRCC). Standardized incidence ratios were calculated to assess the risk of SPMs among the patients.

Results: Overall risk of SPMs was significantly higher among patients with three histological subtypes of CRC than in the general population. The risk of esophagus cancer was significantly increased in SRCC. The risk of small intestine, colon and rectum, and corpus uteri cancers was high in three histological subtypes, with the highest risk observed in SRCC, followed by MA. Increased risks of second stomach, uterus, urinary bladder, kidney, and thyroid cancers were only observed in CA patients, while increased risk of second renal pelvis cancer was limited to MA patients. Furthermore, the high overall risk of SPMs in CA patients persisted regardless of clinicopathological factors. After surgery combined with chemotherapy treatment, CA patients were more prone to developing second small intestine, colon and rectum cancers than those treated with surgery only. A lower second prostate cancer risk was observed in rectal CA patients treated with surgery combined with radiotherapy than in patients treated with surgery only.

Conclusion: The present study revealed that the risk of developing SPMs after CRC varied based on the histological subtypes of the first primary CRC. Although the mechanisms underlying the observed patterns of SPM risk remain unknown, the study provided insights into future cancer surveillance based on the histological subtypes of CRC.

Smoking and colorectal cancer: A pooled analysis of 10 population-based cohort studies in Japan

Smoking has been consistently associated with the risk of colorectal cancer (CRC) in Western populations; however, evidence is limited and inconsistent in Asian people. To assess the association of smoking status, smoking intensity and smoking cessation with colorectal risk in the Japanese population, we performed a pooled analysis of 10 population-based cohort studies. Study-specific hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox's proportional hazards model and then pooled using a random-effects model. Among 363 409 participants followed up for 2 666 004 person-years, 9232 incident CRCs were identified. In men, compared with never smokers, ever smokers showed higher risk of CRC. The HRs (95% CI) were 1.19 (1.10-1.29) for CRC, 1.19 (1.09-1.30) for colon cancer, 1.28 (1.13-1.46) for distal colon cancer and 1.21 (1.07-1.36) for rectal cancer. Smoking was associated with risk of CRC in a dose-response manner. In women, compared with never smokers, ever smokers showed increased risk of distal colon cancer (1.47 [1.19-1.82]). There was no evidence of a significant gender difference in the association of smoking and CRC risk. Our results confirm that smoking is associated with an increased risk of CRC, both overall and subsites, in Japanese men and distal colon cancer in Japanese women.