Age-specific Trends in Colorectal Cancer Incidence for Women and Men, 1935-2017

Geographic differences in early-onset breast cancer incidence trends in the USA, 2001-2020, is it time for a geographic risk score?

PURPOSE

Breast cancer (BC) incidence is increasing in US women under 40, with variation across racial and ethnic groups. It is not yet known if incidence trends also vary by geography within the USA, which may inform whether place-based exposures contribute to BC risk in younger women.

METHODS

Using the US Cancer Statistics database, we analyzed age-adjusted BC incidence rates from 2001 to 2020 in women aged 25-39. We calculated the average annual percent change (AAPC) using Joinpoint regression and performed age-period-cohort analyses.

RESULTS

From 2001 to 2020, BC incidence in women under 40 increased by more than 0.50% per year in 21 states, while remaining stable or decreasing in the other states. Incidence was 32% higher in the five states with the highest rates compared to the five states with the lowest rates. The Western region had the highest rate of increase (AAPC = 0.76, 95% CI 0.56-0.96), despite having the lowest absolute incidence rate from 2001 to 2020. The Northeast had the highest absolute rate of BC among women under 40 and experienced a significant increase over time (AAPC = 0.59, 95% CI 0.36-0.82). The South was the only region where BC under 40 did not increase from 2001 to 2020.

CONCLUSION

These findings support that BC incidence trends in US women under 40 vary by geography, and the range of state-specific risks was comparable in magnitude to other risk measures, such as polygenic risk scores. This suggest that incorporating place-based factors alongside established risk factors into risk prediction may improve our ability to identify groups of younger women at higher risk for early-onset BC.

Physical Activity during Adolescence and Early Adulthood and Breast Cancer Risk before Age 40 Years

BACKGROUND

Breast cancer incidence is increasing in women under age 40, underscoring the need for research on breast cancer risk factors for younger women.

METHODS

We used data from an international family cohort (n = 26,348) to examine whether recreational physical activity (RPA) during adolescence and early adulthood is associated with breast cancer risk before age 40. The cohort includes 2,502 women diagnosed with breast cancer before age 40, including 2,408 diagnosed before study enrollment (68% within 5 years of enrollment). Women reported their average hours per week of moderate and strenuous RPA during adolescence (12-17 years) and early adulthood (25-34 years), which were converted to total age-adjusted metabolic equivalents per week and categorized into quartiles. We conducted attained age analyses until age 40 (follow-up time began at age 18) using Cox proportional hazards regression models adjusted for study center, race and ethnicity, and education.

RESULTS

Being in the highest versus lowest quartile of RPA during adolescence and early adulthood were respectively associated with 12% [HR (95% confidence interval, or CI), 0.88 (0.78-0.98)] and 16% [HR (95% CI), 0.84 (0.74-0.95) lower breast cancer risks before age 40. Being in the highest quartile of RPA during both adolescence and early adulthood (Pearson correlation = 0.52) versus neither time point was associated with a 22% lower risk [HR (95% CI), 0.78 (0.68-0.89)].

CONCLUSIONS

Findings suggest that RPA during adolescence and early adulthood may lower breast cancer risk before age 40.

IMPACT

Policies promoting physical activity during adolescence and early adulthood may be important for reducing the growing burden of breast cancer in younger women.

ALYREF recruits ELAVL1 to promote colorectal tumorigenesis via facilitating RNA m5C recognition and nuclear export

ALYREF can recognize 5-methylcytosine (m5C) decoration throughout RNAs to regulate RNA metabolism. However, its implications in cancer and precise regulatory mechanisms remain largely elusive. Here, we demonstrated that ALYREF supported colorectal cancer (CRC) growth and migration. Integrated analysis of ALYREF-RIP-Bis-seq and transcriptome profiles identified ribosomal protein S6 kinase B2 (RPS6KB2) and regulatory-associated protein of mTOR (RPTOR) as ALYREF's possible downstream effectors. Mechanistically, ALYREF formed a complex with ELAV like RNA binding protein 1 (ELAVL1) to cooperatively promote m5C recognition and nuclear export of the two mRNAs. Moreover, ALYREF protein was highly expressed in tumor tissues of CRC patients, which predicted their poor prognosis. E2F transcription factor 6 (E2F6)-mediated transactivation gave a molecular insight into ALYREF overexpression. Collectively, ALYREF recruits ELAVL1 to collaboratively facilitate m5C recognition and nuclear export of RPS6KB2 and RPTOR transcripts for colorectal tumorigenesis, providing RNA m5C methylation as promising therapeutic targets and prognostic biomarkers for CRC.

Unveiling the overlooked fungi: the vital of gut fungi in inflammatory bowel disease and colorectal cancer

The fungi of the human microbiota play important roles in the nutritional metabolism and immunological balance of the host. Recently, research has increasingly emphasised the role of fungi in modulating inflammation in intestinal diseases and maintaining health in this environment. It is therefore necessary to understand more clearly the interactions and mechanisms of the microbiota/pathogen/host relationship and the resulting inflammatory processes, as well as to offer new insights into the prevention, diagnosis and treatment of inflammatory bowel disease (IBD), colorectal cancer (CRC) and other intestinal pathologies. In this review, we comprehensively elucidate the fungal-associated pathogenic mechanisms of intestinal inflammation in IBD and related CRC, with an emphasis on three main aspects: the direct effects of fungi and their metabolites on the host, the indirect effects mediated by interactions with other intestinal microorganisms and the immune regulation of the host. Understanding these mechanisms will enable the development of innovative approaches based on the use of fungi from the resident human microbiota such as dietary interventions, fungal probiotics and faecal microbiota transplantation in the prevention, diagnosis and treatment of intestinal diseases.

Global obesity epidemic and rising incidence of early-onset cancers

Background

Incidence of early-onset cancers at multiple organ sites has increased worldwide in recent decades. We investigated whether such increasing trends could be explained by trends in obesity.

Methods

We obtained incidence data for 21 common cancers among 25-49-year-olds during 2000-2012 in 42 countries from the Cancer Incidence in Five Continents database. Nine cancers we examined have been classified as obesity-related by the International Agency for Research on Cancer. Estimates of overweight and obesity prevalence came from the Non-communicable Disease Risk Factor Collaboration. Using country-level data, we examined whether changes in the prevalence of overweight and obesity combined were correlated with changes in cancer incidence, after accounting for various time lags (0-15 years) between exposure and cancer diagnosis. To test the validity of our approach, we conducted negative control analyses (using non-obesity-related cancers as the outcome variable, and per-capita gross national income as the exposure variable), and sensitivity and supplemental analyses using alternative data streams or processing.

Results

We found increased incidence for six of nine obesity-related and seven of twelve non-obesity-related cancers in 25-49-year-olds. These increases were more predominant in Western countries (particularly Australia, the USA, Canada, Norway, the Netherlands, and Lithuania). For four obesity-related cancers displaying increased incidence (colon, rectum, pancreas, kidney), changes in cancer incidence were positively correlated with changes in overweight and obesity prevalence. When accounting for a 15-year lag, the estimated correlation was 0.27 (95% confidence interval (CI) = -0.04, 0.53; P = 0.090) for colon cancer, 0.33 (95% CI = 0.02, 0.58; P = 0.036) for rectal cancer, 0.39 (95% CI = 0.08, 0.64; P = 0.018) for pancreatic cancer, and 0.22 (95% CI = -0.10, 0.50; P = 0.173) for kidney cancer. Similar correlations were found in the sensitivity and supplemental analyses. We did not find similar correlations with excess body weight for the non-obesity-related early-onset cancers, nor correlations with per-capita gross national income for any cancer types, in the negative control analyses.

Conclusions

Worldwide increases in early-onset colon, rectal, pancreatic, and kidney cancers may have been partly driven by increases in excess body weight. The increases in other early-onset cancers, however, were likely driven by other factors deserving of further investigation.

Comparing cohort and period trends of early-onset colorectal cancer: a global analysis

BACKGROUND

Incidence of early-onset colorectal cancer (CRC) has increased globally in recent decades. We examined early-onset CRC incidence trends worldwide for potential cohort effects, defined as changes associated with time of birth (eg, early-life exposure to carcinogens), and period effects, defined as changes associated with calendar periods (eg, screening programs).

METHODS

We obtained long-term incidence data for early-onset CRC diagnosed in patients aged 20 to 49 years through the year 2012 for 35 countries in the Cancer Incidence in Five Continents database. We used a smoothing method to help compare cohort and period trends of early-onset CRC and used an age-period-cohort model to estimate cohort and period effects.

RESULTS

Cohort effects had a more dominant role than period effects in the early-onset CRC incidence in Shanghai (China), the United Kingdom, Australia, New Zealand, Canada, the United States, and Osaka (Japan). The smoothed trends show the specific birth cohorts when early-onset CRC began to increase: the 1940s-1950s birth cohorts in the United States; the 1950s-1960s birth cohorts in other Western countries; the 1960s birth cohorts in Osaka; and the 1970s-1980s birth cohorts in Shanghai. Such increases occurred earlier for early-onset cancers of the rectum than of the colon. For the other countries, the results were less clear.

CONCLUSIONS

Recent birth cohorts may have been exposed to risk factors different from earlier cohorts, contributing to increased early-onset CRC incidence in several developed countries or regions in the West and Asia. Such increases began in earlier birth cohorts in Western countries than in developed regions of Asia.

Environmental drivers of the rising incidence of early-onset colorectal cancer in the United States

Incidence of early-onset (diagnosed before age 50) colorectal cancer (EOCRC) has increased alarmingly since the 1990s in the United States. This study investigated what environmental exposures may have driven this increase. We obtained EOCRC incidence data from the Surveillance, Epidemiology, and End Results Program, and data for 11 exposures, for example, body mass index (BMI), from long-term national surveys. We aggregated these data for 30 to 49-year-olds during 1992 to 2016 by population subgroups defined by calendar period, age, race and sex, and used negative binomial regression models to identify and estimate associations of EOCRC with multiple exposures. Furthermore, we used counterfactual modeling to quantify contributions of identified risk factors to EOCRC incidence. The top models (with lowest Bayesian Information Criteria) consistently identified excess body weight, represented by overweight and obesity (BMI ≥25) or obesity alone (BMI ≥30), as the strongest risk factor. The best-performing model estimated increased EOCRC incidence due to overweight and obesity, with an incidence rate ratio (95% confidence interval) of 1.20 (1.17-1.22) for white men, 1.04 (1.00-1.08) for black men, 1.17 (1.15-1.21) for white women and 1.03 (0.97-1.08) for black women. Increases in overweight and obesity prevalence contributed to an estimated 30% (standard error: 1%) for men and 28% (standard error: 2%) for women of ECORC incidence during 1992 to 2016. These findings suggest excess body weight substantially contributed to and is likely a primary driver of the rising incidence of EOCRC in the United States. Prevention of excess weight gain may help lower colorectal cancer risk early in life.

Dietary Factors and Early-Onset Colorectal Cancer in the United States-an Ecologic Analysis

BACKGROUND

Incidence of early-onset colorectal cancer (EOCRC; e.g., diagnosed before age 50) in the United States has increased substantially since the 1990s but the underlying reasons remain unclear.

METHODS

We examined the ecologic associations between dietary factors and EOCRC incidence in adults aged 25-49 during 1977-2016 in the United States, using negative binomial regression models, accounting for age, period, and race. The models also incorporated an age-mean centering (AMC) approach to address potential confounding by age. We stratified the analysis by sex and computed incidence rate ratio (IRR) for each study factor. Study factor data (for 18 variables) came from repeated national surveys; EOCRC incidence data came from the Surveillance Epidemiology, and End Results Program.

RESULTS

Results suggest that confounding by age on the association with EOCRC likely existed for certain study factors (e.g., calcium intake), and that AMC can alleviate the confounding. EOCRC incidence was positively associated with smoking [IRR (95% confidence interval (CI): 1.17 (1.10-1.24) for men; 1.15 (1.09-1.21) for women] and alcohol consumption [IRR (95% CI), 1.08 (1.04-1.12) for men; 1.08 (1.04-1.11) for women]. No strong associations were found for most other study factors (e.g., fiber and calcium).

CONCLUSIONS

Alcohol consumption was positively associated with EOCRC and has increased among young adults since the 1980s, which may have contributed to the EOCRC incidence increases since the 1990s. The AMC approach may help alleviate age confounding in similar ecologic analyses.

IMPACT

Increases in alcohol consumption may have contributed to the recent increases in colorectal cancer incidence among young adults. See related commentary by Ni et al., p. 164.

Benefits of tailored hepatocellular carcinoma screening in patients with cirrhosis on cancer-specific and overall mortality: A modeling approach

To validate cancer screening programs, experts recommend estimating effects on case fatality rates (CFRs) and cancer-specific mortality. This study evaluates hepatocellular carcinoma (HCC) screening in patients with cirrhosis for those outcomes using a modeling approach. We designed a Markov model to assess 10-year HCC-CFR, HCC-related, and overall mortality per 100,000 screened patients with compensated cirrhosis. The model evaluates different HCC surveillance intervals (none, annual [12 months], semiannual [6 months], or quarterly [3 months]) and imaging modalities (ultrasound [US] or magnetic resonance imaging [MRI]) in various annual incidences (0.2%, 0.4%, or 1.5%). Compared to no surveillance, 6-month US reduced the 10-year HCC-CFR from 77% to 46%. With annual incidences of 0.2%, 0.4%, and 1.5%, the model predicted 281, 565, and 2059 fewer HCC-related deaths, respectively, and 187, 374, and 1356 fewer total deaths per 100,000 screened patients, respectively. Combining alpha-fetoprotein screening to 6-month US led to 32, 63, and 230 fewer HCC-related deaths per 100,000 screened patients for annual incidences of 0.2%, 0.4%, and 1.5%, respectively. Compared to 6-month US, 3-month US reduced cancer-related mortality by 14%, predicting 61, 123, and 446 fewer HCC-related deaths per 100,000 screened patients with annual incidences of 0.2%, 0.4%, and 1.5%, respectively. Compared to 6-month US, 6-month MRI (-17%) and 12-month MRI (-6%) reduced HCC-related mortality. Compared to 6-month US, overall mortality reductions ranged from -0.1% to -1.3% when using 3-month US or MRI. A US surveillance interval of 6 months improves HCC-related and overall mortality compared to no surveillance. A shorter US interval or using MRI could reduce HCC-CFR and HCC-related mortality, with a modest effect on overall mortality.

Gut microbiota, inflammatory bowel disease and colorectal cancer

The gut microbiota is a complex community of microorganisms that inhabit the digestive tracts of humans, living in symbiosis with the host. Dysbiosis, characterized by an imbalance between the beneficial and opportunistic gut microbiota, is associated with several gastrointestinal disorders, such as irritable bowel syndrome (IBS); inflammatory bowel disease (IBD), represented by ulcerative colitis and Crohn's disease; and colorectal cancer (CRC). Dysbiosis can disrupt the mucosal barrier, resulting in perpetuation of inflammation and carcinogenesis. The increase in some specific groups of harmful bacteria, such as Escherichia coli (E. coli) and enterotoxigenic Bacteroides fragilis (ETBF), has been associated with chronic tissue inflammation and the release of pro-inflammatory and carcinogenic mediators, increasing the chance of developing CRC, following the inflammation-dysplasia-cancer sequence in IBD patients. Therefore, the aim of the present review was to analyze the correlation between changes in the gut microbiota and the development and maintenance of IBD, CRC, and IBD-associated CRC. Patients with IBD and CRC have shown reduced bacterial diversity and abundance compared to healthy individuals, with enrichment of Firmicute sand Bacteroidetes. Specific bacteria are also associated with the onset and progression of CRC, such as Fusobacterium nucleatum, E. coli, Enterococcus faecalis, Streptococcus gallolyticus, and ETBF. Future research can evaluate the advantages of modulating the gut microbiota as preventive measures in CRC high-risk patients, directly affecting the prognosis of the disease and the quality of life of patients.

The microbiome, gastrointestinal cancer, and immunotherapy

The gastrointestinal tract greatly contributes to global cancer burden and cancer-related deaths. The microbiota represents the population of microorganisms that live in and around the body, located primarily in the gastrointestinal tract. The microbiota has been implicated in colorectal cancer development and progression, but its role in cancer therapy for the gastrointestinal tract is less defined, especially for extra-intestinal cancers. In this review, we discuss the past 5 years of research into microbial involvement in immune-related therapies for colorectal, pancreatic, hepatic, and gastric cancers, with the goal of highlighting recent advances and new areas for investigation in this field.