Rising incidence of early-onset colorectal cancer in Australia over two decades: report and review

Age-specific trends in colorectal, appendiceal, and anal tumour incidence by histological subtype in Australia from 1990 to 2020: a population-based time-series analysis

Background

Early-onset bowel cancer incidence (age <50 years) has increased worldwide and is highest in Australia, but how this varies across histology and anatomical site remains unclear. We aimed to investigate appendiceal, proximal colon, distal colon, rectal, and anal cancer incidence trends by age and histology in Australia.

Methods

Cancer incidence rate data were obtained from all Australian cancer registries (1990-2020 period). Birth cohort-specific incidence rate ratios (IRRs) and annual percentage change in rates were estimated using age-period-cohort modelling and joinpoint regression.

Findings

After excluding neuroendocrine neoplasms, early-onset cancer incidence rose 5-9% annually, yielding 5,341 excess cases (2 per 100,000 person-years; 12% appendix, 45% colon, 36% rectum, 7% anus; 20-214% relative increase). Trends varied by site, period, and age: appendiceal cancer rose from 1990-2020 in 30-49-year-olds; colorectal cancers rose from around 1990-2010 in 20-29-year-olds and from 2010-2020 in 30-39-year-olds; anal cancer rose from 1990-2009 in 40-49-year-olds. Across all sites, IRRs increased with successive birth cohorts since 1960. Notably, adenocarcinoma incidence in the 1990s versus 1950s birth cohort was 2-3-fold for colorectum and 7-fold for appendix. The greatest subtype-specific increases occurred for appendiceal mucinous adenocarcinoma, colorectal non-mucinous adenocarcinoma, and anal squamous cell carcinoma. Only later-onset (age ≥50) colorectal and anal adenocarcinoma rates declined. Appendiceal tumours, neuroendocrine neoplasms (all sites), anorectal squamous cell carcinomas, and colon signet ring cell carcinomas rose across early-onset and later-onset strata.

Interpretation

Appendiceal, colorectal, and anal cancer incidence is rising in Australia with variation across age and histology, underscoring the need to identify factors driving these trends.

Funding

ALM is supported by an Australian Government Research Training Program Scholarship, Rowden White Scholarship, and WP Greene Scholarship. DDB is supported by a National Health and Medical Research Council of Australia (NHMRC) Investigator grant (GNT1194896), a University of Melbourne Dame Kate Campbell Fellowship, and by funding awarded to The Colon Cancer Family Registry (CCFR, www.coloncfr.org) from the National Cancer Institute (NCI), National Institutes of Health (NIH) [award U01 CA167551]. MAJ is supported by an NHMRC Investigator grant (GNT1195099), a University of Melbourne Dame Kate Campbell Fellowship, and by funding awarded to the CCFR from NCI, NIH [award U01 CA167551].

Recalibrating an Established Microsimulation Model to Capture Trends and Projections of Colorectal Cancer Incidence and Mortality

BackgroundChanging colorectal cancer (CRC) incidence rates, including recent increases for people younger than 50 y, need to be considered in planning for future cancer control and screening initiatives. Reliable estimates of the impact of changing CRC trends on the National Bowel Cancer Screening Program (NBCSP) are essential for programmatic planning in Australia. An existing microsimulation model of CRC, Policy1-Bowel, was updated to reproduce Australian CRC trends data and provide updated projections of CRC- and screening-related outcomes to inform clinical practice guidelines for the prevention of CRC.MethodsPolicy1-Bowel was recalibrated to reproduce statistical age-period-cohort model trends and projections of CRC incidence for 1995-2045 in the absence of the NBCSP as well as published data on CRC incidence trends, stage distribution, and survival in 1995-2020 in Australia. The recalibrated Policy1-Bowel predictions were validated by comparison with published Australian CRC mortality trends for 1995-2015 and statistical projections to 2040. Metamodels were developed to aid the calibration process and significantly reduce the computational burden.ResultsPolicy1-Bowel was recalibrated, and best-fit parameter sets were identified for lesion incidence, CRC stage progression rates, detection rates, and survival rates by age, sex, bowel location, cancer stage, and birth year. The recalibrated model was validated and successfully reproduced observed CRC mortality rates for 1995-2015 and statistical projections for 2016-2030.ConclusionThe recalibrated Policy1-Bowel model captures significant additional detail on the future incidence and mortality burden of CRC in Australia. This is particularly relevant as younger cohorts with higher CRC incidence rates approach screening ages to inform decision making for these groups. The metamodeling approach allows fast recalibration and makes regular updates to incorporate new evidence feasible.HighlightsIn Australia, colorectal cancer incidence rates are increasing for people younger than 50 y but decreasing for people older than 50 y, and colorectal cancer survival is improving as new treatment technologies emerge.To evaluate the future health and economic impact of screening and inform policy, modeling must include detailed trends and projections of colorectal cancer incidence, mortality, and diagnosis stage.We used novel techniques including integrative age-period cohort projections and metamodel calibration to update Policy1-Bowel, a detailed microsimulation of colorectal cancer and screening in Australia.

Impact of Small Area Level Deprivation on Colorectal Cancer Survival: Findings from the Regional Cancer Registry in Korea

BACKGROUND/OBJECTIVES

Research on the relationship between small-area-level deprivation and cancer survival, particularly for colorectal cancer (CRC), is lacking. Therefore, we investigated the relationship among small area-level deprivation, individual-level factors, and CRC survival using data from the Busan Regional Cancer Registry.

METHODS

We analyzed 34,999 patients with CRC from the Busan Regional Cancer Registry from 2003 to 2020. The primary outcome was CRC mortality. The explanatory variables at the individual level included age, gender, cancer stage, and year of diagnosis, whereas the Deprivation Index (DI) was used at the regional level. We conducted a multilevel survival analysis with frailty to assess the impact of individual- and area-level factors on survival probabilities.

RESULTS

In the multilevel survival model, each unit increase in the DI at the area level was associated with a 6.6% decrease in survival probability. When applying Model 2 and deriving regional estimates using the empirical Bayesian estimation method, the graph of the DI (x-axis) against survival probability (y-axis) showed that the slope of the regional DI for the 3-year and 5-year survival probabilities increased compared with the 1-year rate across all stages of the disease. Additionally, the slopes were steeper for the distant stage than for the local or regional stages.

CONCLUSIONS

Small-area level deprivation negatively affects CRC survival, especially in distant-stage patients and those with longer disease duration.

Expert consensus on the optimal management of BRAFV600E-mutant metastatic colorectal cancer in the Asia-Pacific region

The burden of colorectal cancer (CRC) is high in the Asia-Pacific region, and several countries in this region have among the highest and/or fastest growing rates of CRC in the world. A significant proportion of patients will present with or develop metastatic CRC (mCRC), and BRAFV600E-mutant mCRC represents a particularly aggressive phenotype that is less responsive to standard chemotherapies. In light of recent therapeutic advances, an Asia-Pacific expert consensus panel was convened to develop evidence-based recommendations for the diagnosis, treatment, and management of patients with BRAFV600E-mutant mCRC. The expert panel comprised nine medical oncologists from Australia, Hong Kong, Singapore, and Taiwan (the authors), who met to review current literature and develop eight consensus statements that describe the optimal management of BRAFV600E-mutant mCRC in the Asia-Pacific region. As agreed by the expert panel, the consensus statements recommend molecular testing at diagnosis to guide individualized treatment decisions, propose optimal treatment pathways according to microsatellite stability status, advocate for more frequent monitoring of BRAFV600E-mutant mCRC, and discuss local treatment strategies for oligometastatic disease. Together, these expert consensus statements are intended to optimize treatment and improve outcomes for patients with BRAFV600E-mutant mCRC in the Asia-Pacific region.

The Relevance of Sex and Age as Non-Modifiable Risk Factors in Relation to Clinical-Pathological Parameters in Colorectal Cancer

BACKGROUND AND OBJECTIVES

We aimed to assess the significance of sex and age compared to other clinical-pathological parameters in colorectal cancer (CRC).

MATERIALS AND METHODS

Our study included a retrospective approach to CRC patients who underwent surgery at the 'Pius Brinzeu' County Clinical Emergency Hospital in Timisoara (PBECCHT), Romania. The analyzed parameters were: patient age and sex, tumor location, histological type, differentiation grade (G), extent of tumor (pT), lymph-node status (pN), distant metastasis status (pM), and lymphovascular invasion (LVI). The population was divided into three groups based on age, with those under 49 years old, 50 to 69 years old, and elderly (>70).

RESULTS

The study's inclusion criteria were met by 1885 patients, with a male-to-female ratio of 1.39:1. There were significant differences between the sexes in the anatomical location of tumors (p < 0.0001). Younger patients were more likely to have deeply invasive tumors (p = 0.0096), LVI (p = 0.0332), lymph-node metastases (p = 0.0158), and metastatic disease (p = 0.0017).

CONCLUSIONS

Over the ten-year period reviewed, the frequency of CRC cases has progressively increased, with males being diagnosed more often. In terms of patient age, the young population exhibits clinical features of aggressive evolution. Patient sex did not influence the analyzed parameters, except for tumor location, where right colon tumors are slightly more common in females.

Breast and bowel cancers diagnosed in people 'too young to have cancer': A blueprint for research using family and twin studies

Young breast and bowel cancers (e.g., those diagnosed before age 40 or 50 years) have far greater morbidity and mortality in terms of years of life lost, and are increasing in incidence, but have been less studied. For breast and bowel cancers, the familial relative risks, and therefore the familial variances in age-specific log(incidence), are much greater at younger ages, but little of these familial variances has been explained. Studies of families and twins can address questions not easily answered by studies of unrelated individuals alone. We describe existing and emerging family and twin data that can provide special opportunities for discovery. We present designs and statistical analyses, including novel ideas such as the VALID (Variance in Age-specific Log Incidence Decomposition) model for causes of variation in risk, the DEPTH (DEPendency of association on the number of Top Hits) and other approaches to analyse genome-wide association study data, and the within-pair, ICE FALCON (Inference about Causation from Examining FAmiliaL CONfounding) and ICE CRISTAL (Inference about Causation from Examining Changes in Regression coefficients and Innovative STatistical AnaLysis) approaches to causation and familial confounding. Example applications to breast and colorectal cancer are presented. Motivated by the availability of the resources of the Breast and Colon Cancer Family Registries, we also present some ideas for future studies that could be applied to, and compared with, cancers diagnosed at older ages and address the challenges posed by young breast and bowel cancers.

Colorectal polyps in young adults: a retrospective review of colonoscopy data from Toowoomba and the Darling Downs

BACKGROUND

Polyps are the predominant precursors of colorectal cancer. In the past three decades, the incidence and mortality rates of colorectal cancer have been increasing in adults younger than 50 years.

AIMS

The aim of this clinical audit was to evaluate the prevalence, characteristics and clinical associations of polyps in adults aged 18-49 years presenting to an established private gastroenterology clinic in the Toowoomba Darling Downs region.

METHODS

The audit included data from 353 patient records held by the Toowoomba Gastroenterology Clinic. Data extracted from patient medical records through the Medical Director program software contained structured endoscopy/colonoscopy and histology reports of excised lesions of patients presenting to the clinic. The extract involved identifying all patients aged 18-49 years in the database from January 2019 to March 2022. Patients were screened based on audit inclusion and exclusion criteria. Patients were risk stratified for recommended surveillance intervals as per Australian Clinical Guidelines.

RESULTS

Of the sample population, 33.4% were identified with polyps and 22.4% were identified with neoplastic polyps (NPs). A total of 6.7% of 18- to 29-year-old patients were identified with intermediate risk for colorectal cancer (CRC) screening, and 19.8% and 19.3% of 30- to 39-year-old and 40- to 49-year-old patients identified with intermediate or high risk for CRC screening respectively. Increased age, greater size of polyps and surveillance of previous polyps were associated with increased NP prevalence.

CONCLUSIONS

Data from this audit supported the temporal trend of increasing prevalence of polyps in adults younger than 50 years. Patient cohorts aged 30-39 and 40-49 years may benefit from earlier first colonoscopies. Findings could be the impetus for future research in young adults presenting for colonoscopy.

Early onset metastatic colorectal cancer in Australia

BACKGROUND

Colorectal cancer (CRC) incidence and mortality rates have been increasing among young patients (YP), for uncertain reasons. It is unclear whether YP have a distinct tumor biology or merit a different treatment approach to older patients (OP).

METHODS

We reviewed prospectively collected data from consecutive patients with metastatic CRC (MCRC) enrolled in the multi-site Treatment of Recurrent and Advanced Colorectal Cancer (TRACC) Australian registry. Clinicopathological features, treatment and survival outcomes were compared between YP (<50 years) and OP (≥50 years).

RESULTS

Of 3692 patients diagnosed August 2009 - March 2023, 14 % (513) were YP. YP were more likely than OP to be female (52% vs. 40 %, P < 0.0001), have ECOG performance status 0-1 (94% vs. 81 %, P < 0.0001), to have a left-sided primary (72% vs. 63 %, P = 0.0008) and to have fewer comorbidities (90% vs. 60 % Charleston score 0, P < 0.0001). There were no differences in the available molecular status, which was more complete in YP. YP were more likely to have de novo metastatic disease (71% vs. 57 %, P < 0.0001). YP were more likely to undergo curative hepatic resection (27% vs. 17 %, P < 0.0001), to receive any chemotherapy (93% vs. 78 % (P < 0.0001), and to receive 3+ lines of chemotherapy (30% vs. 24 % (P < 0.0034)). Median first-line progression free survival (10.2 versus 10.6 months) was similar for YP vs OP, but overall survival (32.1 versus 25.4 months, HR = 0.745, P < 0.0001) was longer in YP.

CONCLUSION

Known prognostic variables mostly favored YP versus OP with newly diagnosed mCRC, who were also more heavily treated. Consistent with this, overall survival outcomes were improved. This data does not support that CRC in YP represent a distinct subset of mCRC patients, or that a modified treatment approach is warranted.

The global burden and trends analysis of early-onset colorectal cancer attributable to dietary risk factors in 204 countries and territories, 1990-2019: a secondary analysis for the global burden of disease study 2019

Background

Rising trends in early-onset colorectal cancer (CRC) burden have been observed, but the distribution and temporal patterns of early-onset CRC attributable to dietary risks remain unclear.

Objectives

This study aimed to estimate the burden of early-onset CRC attributable to dietary risk factors globally, regionally, and nationally, by age and sex, from 1990 to 2019.

Methods

The absolute number and age-specific rates (ASR) of diet-related early-onset CRC burden, as well as summary exposure value (SEV) of attributable dietary risk factors, were extracted from the Global Burden of Disease (GBD) Study 2019. The temporal changes in the burden between 1990 and 2019 were analyzed by calculating the percentage change in the absolute number of burden and the estimated annual percentage change (EAPC) in ASR of burden. The annualized rates of change (ARC) were calculated to evaluate the variation trend of SEV.

Results

In 2019, diet-related early-onset CRC caused 30,096 (95% UI: 23,148 to 36,091) death cases and 1,465,755 (95% UI: 1,126,489 to 1,761,661) DALYs worldwide, accounting for 34.8% deaths and 34.4% DALYs of overall early-onset CRC, respectively. Moreover, a diet low in milk (responsible for 16.5% [95% UI: 11.1 to 21.9%] of DALYs in 2019), low in whole grains (15.2% [95% UI: 5.9 to 19.9%]), low in calcium (14.3% [95% UI: 10.7 to 18.9%]), high in red meat (5.3% [95% UI: 1.7 to 9.5%]), high in processed meat (2.5% [95% UI: 0.9 to 4.0%]), and low in fiber (2.3% [95% UI: 0.9 to 4.2%]) were early-onset CRC attributable dietary risk factors. The age-specific DALYs rate of early-onset CRC attributable to each dietary risk factor generally showed an increasing trend globally between 1990 and 2019, except for low intake of fiber (EAPC = -0.57, 95% CI: -0.76 to -0.38). In addition, from 1990 to 2019, males have a higher burden than females and this gap may continue to widen due to the increasing difference between the sexes in most dietary risk factors. Furthermore, dietary risks-attributable early-onset CRC burden has shifted from regions with high socio-demographic index (SDI) to high-middle and middle SDI quintiles with uncontrolled dietary risks.

Conclusion

Early-onset CRC remains a concerning issue globally, and effective prevention and modification of dietary risk factors holds great promise to reduce early-onset CRC-related burden. Prioritizing diet improvement for males is critical and urgent for CRC control efforts, particularly for those living in developing countries with ongoing dietary pattern transition.

Colorectal cancer and its attributable risk factors in East Asia, 1990-2030

BACKGROUND

The disease burden of colorectal cancer in East Asia has been at a high level. However, the epidemiological characteristics of the disease burden in this region have not been systematically studied.

METHOD

Data were obtained from the Global Burden of Disease 2019 program. Joinpoint analysis was used to identify long-term trends in mortality of colorectal cancer. Independent effects of age, period, and cohort were detected by the age-period-cohort model. The Bayesian age-period-cohort model was performed to predict the burden of colorectal cancer across East Asia by 2030.

RESULTS

From 1990 to 2019, the average annual percentage change (AAPC) showed upward trends in mainland China (1.05 [95% confidence interval (CI)], 0.82, 1.28) as well as Taiwan Province of China (1.81 [95% CI], 1.51, 2.10) but downward in Japan (-0.60 [95% CI], -0.70, -0.49) (P < 0.05). Attributable risk factors for colorectal cancer in East Asia remained stable over 30 years, while the risk of metabolic factors is noteworthy in the future. In the next decade, the age-standardized death rate (ASDR) of colorectal cancer in China was predicted to surpass that of Japan and South Korea in expectation.

CONCLUSION

The mortality of colorectal cancer is escalating in developing countries, while it is gradually declining in high-income countries across East Asia. Nonetheless, the disease burden of colorectal cancer in high-income countries remains substantial level.

Elevated cardiovascular risk and acute events in hospitalized colon cancer survivors: A decade-apart study of two nationwide cohorts

BACKGROUND

Over the years, strides in colon cancer detection and treatment have boosted survival rates; yet, post-colon cancer survival entails cardiovascular disease (CVD) risks. Research on CVD risks and acute cardiovascular events in colorectal cancer survivors has been limited.

AIM

To compare the CVD risk and adverse cardiovascular outcomes in current colon cancer survivors compared to a decade ago.

METHODS

We analyzed 2007 and 2017 hospitalization data from the National Inpatient Sample, studying two colon cancer survivor groups for CVD risk factors, mortality rates, and major adverse events like pulmonary embolism, arrhythmia, cardiac arrest, and stroke, adjusting for confounders via multivariable regression analysis.

RESULTS

Of total colon cancer survivors hospitalized in 2007 (n = 177542) and 2017 (n = 178325), the 2017 cohort often consisted of younger (76 vs 77 years), male, African-American, and Hispanic patients admitted non-electively vs the 2007 cohort. Furthermore, the 2017 cohort had higher rates of smoking, alcohol abuse, drug abuse, coagulopathy, liver disease, weight loss, and renal failure. Patients in the 2017 cohort also had higher rates of cardiovascular comorbidities, including hypertension, hyperlipidemia, diabetes, obesity, peripheral vascular disease, congestive heart failure, and at least one traditional CVD (P < 0.001) vs the 2007 cohort. On adjusted multivariable analysis, the 2017 cohort had a significantly higher risk of pulmonary embolism (PE) (OR: 1.47, 95%CI: 1.37-1.48), arrhythmia (OR: 1.41, 95%CI: 1.38-1.43), atrial fibrillation/flutter (OR: 1.61, 95%CI: 1.58-1.64), cardiac arrest including ventricular tachyarrhythmia (OR: 1.63, 95%CI: 1.46-1.82), and stroke (OR: 1.28, 95%CI: 1.22-1.34) with comparable all-cause mortality and fewer routine discharges (48.4% vs 55.0%) (P < 0.001) vs the 2007 cohort.

CONCLUSION

Colon cancer survivors hospitalized 10 years apart in the United States showed an increased CVD risk with an increased risk of acute cardiovascular events (stroke 28%, PE 47%, arrhythmia 41%, and cardiac arrest 63%). It is vital to regularly screen colon cancer survivors with concomitant CVD risk factors to curtail long-term cardiovascular complications.

The Clinicopathological Characteristics of Young-Onset Versus Adult-Onset Colorectal Cancer: A Tertiary Hospital-Based Study

Background

The prevalence of colorectal cancer (CRC) among young individuals is rising worldwide, especially in Malaysia. Investigations are currently employed to distinguish the features of young-onset CRC (YOCRC) from adult-onset CRC (AOCRC). This study aimed to compare the characteristics of patients with YOCRC and AOCRC diagnosed at Hospital Universiti Sains Malaysia (HUSM).

Methods

This was a retrospective study of CRC cases from January 2013 to December 2021. The details of YOCRC (< 50 years old) and AOCRC (≥ 50 years old) patients were retrieved from the laboratory system and medical records. The Pearson's chi-square test, Fisher's exact test and multiple logistic regression were used to compare the AOCRC and YOCRC cases. Statistical significance was defined at a P-value of ≤ 0.05.

Results

The AOCRC (254/319, 79.6%) was more prevalent than YOCRC (65/319, 20.4%), with a predominance of males (53.9%) and Malay sub-population (90.2%). AOCRC and YOCRC shared similarities in left-sided location, high occurrence of adenocarcinoma with moderately differentiated histology and advanced stage of diagnosis. More patients with YOCRC (23.1%) had a family history of cancer than patients with AOCRC. YOCRC also differed from AOCRC by having more specific histological subtypes, such as mucinous adenocarcinoma (15.4%) and signet ring carcinoma (6.2%). In addition, patients with YOCRC commonly presented with a low density of tumour-infiltrating lymphocytes (TILs) (60%). Multiple logistic regression showed a family history of CRC (adjusted odds ratio [AOR] = 3.75, P = 0.003) and histological type (AOR = 15.21, P < 0.001) are more likely to cause YOCRC than diabetes (AOR = 0.06, P < 0.001) and hypertension (AOR = 0.14, P < 0.001) comorbidities, which are associated with AOCRC.

Conclusion

Our descriptive study presented the epidemiological and histopathological characteristics of AOCRC and YOCRC in HUSM, providing current information on distinguishing features between the groups.

The burden of young-onset pancreatic cancer and its risk factors from 1990 to 2019: A systematic analysis of the global burden of disease study 2019

OBJECTIVE

To investigate worldwide incidence, deaths, disability-adjusted life years (DALYs) and risk factors for young-onset pancreatic cancer (YOPC) using the Global Burden of Disease Study 2019-20 data.

METHODS

We queried the Global Health Data Exchange tool for "pancreatic cancer" and "incidence", "deaths" as the "measure", and "DALYs" as the "cause" for the age group of 15-49 years to determine global, regional, and national trends in the incidence, deaths, and DALYs of YOPC. Sociodemographic index (SDI) was used to evaluate the associations between socioeconomic development and YOPC. Risk factors including smoking, tobacco use, hi2gh body mass index (BMI), and high fasting plasma glucose (FPG) were evaluated, and their attributable burden was estimated.

RESULTS

Global incidence, death, and DALY rates of YOPC significantly increased from 1990 to 2019 ((0.30 (p = 0.001), 0.25 (p = 0.001), and 11.18 (p = 0.002), respectively). Regions with the highest and lowest incidence, death, and DALY rates of YOPC were Eastern Europe and Central Sub-Saharan Africa, respectively. Incidence, death, and DALY rates increased with increasing age and SDI. Leading risk factors for YOPC in 2019 were smoking and tobacco use. DALYs attributable to smoking and tobacco use decreased from 1990 to 2019, especially in females, while those attributable to high BMI and FPG increased during the same period.

CONCLUSIONS

The global incidence, death and DALY rates of YOPC have significantly increased over 3 decades. Certain regions and nations are witnessing a higher increase in this trend. There is an urgent need for global efforts targeting preventable causes of YOPC.

Towards precision oncology discovery: four less known genes and their unknown interactions as highest-performed biomarkers for colorectal cancer

The goal of this study was to use a new interpretable machine-learning framework based on max-logistic competing risk factor models to identify a parsimonious set of differentially expressed genes (DEGs) that play a pivotal role in the development of colorectal cancer (CRC). Transcriptome data from nine public datasets were analyzed, and a new Chinese cohort was collected to validate the findings. The study discovered a set of four critical DEGs - CXCL8, PSMC2, APP, and SLC20A1 - that exhibit the highest accuracy in detecting CRC in diverse populations and ethnicities. Notably, PSMC2 and CXCL8 appear to play a central role in CRC, and CXCL8 alone could potentially serve as an early-stage marker for CRC. This work represents a pioneering effort in applying the max-logistic competing risk factor model to identify critical genes for human malignancies, and the interpretability and reproducibility of the results across diverse populations suggests that the four DEGs identified can provide a comprehensive description of the transcriptomic features of CRC. The practical implications of this research include the potential for personalized risk assessment and precision diagnosis and tailored treatment plans for patients.

Descriptive Epidemiology of Early-Onset Gastrointestinal Cancers in Iran, 2014-2018

Background

We aim to present incidence rates and geographical distribution of most common early-onset gastrointestinal cancers (EOGICs), including early-onset esophageal cancer (EOEC), gastric cancer (EOGC) and colorectal cancer (EOCRC) in Iran, 2014-2018.

Methods

Data on new cases of EOEC, EOGC and EOCRC were obtained from publicly available annual reports of the Iranian National Population-based Cancer Registry (INPCR). Incidence rates were calculated using the population data available from the Statistical center of Iran. We considered the World standard population for calculation of age-standardized incidence rates (ASR). We also calculated 95% confidence intervals (CIs) for ASR. All rates are presented per 100000 person-years.

Results

Overall, 19,679 new cases of EOGIC were registered by the INPCR between 2014 and 2018. The ASRs (95% CI) of EOEC, EOGC and EOCRC were 0.49 (95% CI: 0.47-0.51), 1.67 (1.63-1.71), and 3.07 (3.01-3.13) per 100,000 person-years, respectively. Our findings indicate decreasing and constant trends in the ASR of EOEC and EOGC during the study period, 2014-2018. There was an increasing trend in the ASR of EOCRC. We also found geographical disparities in the incidence rates of EOGICs across provinces of Iran, suggesting the highest ASRs of EOEC in Golestan (1.3), EOGC in Ilam (2.99) and EOCRC in Ilam (4.49).

Conclusion

Our findings suggested that the incidence rate of EOCRC is consistently increasing. We also found variations in the incidence of EOGICs among different provinces. Further investigations are recommended to clarify the time trends and risk factors of EOGICs in Iran.

Clinical and pathological characteristics of early-onset colorectal cancer in South Korea

Background

Early-onset colorectal cancer (EOCRC) may differ by race and ethnicity, and recently South Korea has witnessed a surge in cases. We aimed to evaluate the clinical and pathological features of patients with EOCRC, and to determine the predictors of overall survival.

Methods

In this retrospective study, EOCRC was defined as CRC diagnosed in patients aged < 50 years, and late-onset CRC was defined as CRC diagnosed in those over 75 years of age. The clinical and pathological characteristics of patients with EOCRC were compared with late-onset CRC. We also used multivariable Cox proportional hazard models to find predictors of overall survival in patients with EOCRC.

Results

The proportion of early-onset CRC was 9.1% of 518 patients with CRC, and the clinical and pathological characteristics were similar between early-onset (n = 47) and late-onset CRC (n = 134). However, EOCRC had a preponderance for distal tumor location (70.2% vs. 50.7%, P = 0.02) and T1-2 stage disease (23.4% vs. 11.2%, P = 0.04), compared with those of late-onset CRC. Using multivariable Cox proportional hazard models, only vascular invasion (hazard ratio = 8.75, 95% confidence interval 1.139‒67.197) was found to be a risk factor for overall survival (P = 0.04) for patients with CRC.

Conclusion

EOCRC had preponderance for distal tumor location and early T-stage disease, compared with late-onset CRC. Considering the increasing incidence of EOCRC, more studies on clinical and pathological characteristics of EOCRC may be warranted.

Adverse Tumour and Host Biology May Explain the Poorer Outcomes Seen in Emergency Presentations of Colon Cancer

OBJECTIVE

To examine the association between tumor/host factors (including the systemic inflammatory response), mode of presentation, and short/long-term outcomes in patients undergoing curative resectional surgery for TNM I to III colon cancer.

BACKGROUND

Emergency presentations of colon cancer are associated with worse long-term outcomes than elective presentations despite adjustment for TNM stage. A number of differences in tumor and host factors have been identified between elective and emergency presentations and it may be these factors that are associated with adverse outcomes.

METHODS

Patients undergoing curative surgery for TNM I to III colon cancer in the West of Scotland from 2011 to 2014 were identified. Tumor/host factors independently associated with the emergency presentation were identified and entered into a subsequent survival model to determine those that were independently associated with overall survival/cancer-specific survival (OS/CSS).

RESULTS

A total of 2705 patients were identified. The emergency presentation was associated with a worse 3-year OS and CSS compared with elective presentations (70% vs 86% and 91% vs 75%). T stage, age, systemic inflammatory grade, anemia (all P < 0.001), N stage ( P = 0.077), extramural venous invasion ( P = 0.003), body mass index ( P = 0.001), and American Society of Anesthesiologists Classification classification ( P = 0.021) were independently associated with emergency presentation. Of these, body mass index [hazard ratio (HR), 0.82], American Society of Anesthesiologists Classification (HR, 1.45), anemia (HR, 1.29), systemic inflammatory grade (HR. 1.11), T stage (HR, 1.57), N stage (HR, 1.80), and adjuvant chemotherapy (HR, 0.47) were independently associated with OS. Similar results were observed for CSS.

CONCLUSIONS

Within patients undergoing curative surgery for colon cancer, the emergency presentation was not independently associated with worse OS/CSS. Rather, a combination of tumor and host factors account for the worse outcomes observed.

Snail inhibits metastasis via regulation of E‑cadherin and is associated with prognosis in colorectal cancer

The overall survival (OS) rate of patients with colorectal cancer (CRC) remains low due to the lack of clear prognostic markers. Therefore, the identification of valuable prognostic markers is urgently required. Snail and E-Cadherin (E-Cad) are important protein molecules in the EMT process and play a crucial role in tumor invasion and metastasis. The present study investigated the clinical significance of Snail and E-cad expression in CRC. Compared with those in adjacent tissue, the expression levels of Snail and E-cad were significantly increased and decreased, respectively, in CRC. Moreover, low Snail and high E-cad expression were associated with clinicopathological features and longer OS time. Furthermore, Snail and E-cad could predict the prognosis of patients with CRC. Reverse transcription-qPCR, Western blotting, Wound scratch assay, High content cell migration experiment, which showed that low Snail or high E-cad expression inhibited invasion and metastasis of CRC. In conclusion, Snail can promote CRC invasion and metastasis by regulating E-cad. Snail and E-cad expression constitute a novel prognostic marker for CRC, and the present study revealed a greater combined effect of Snail and E-cad as effective prognostic markers in CRC for the first time.

A Retrospective Multicenter Study of the Clinicopathological Characteristics and Prognosis of Young Adult Patients with Colorectal Cancer: Effects of Chemotherapy on Prognosis

BACKGROUND

The objective of this study was to evaluate clinicopathologic features of young patients with colorectal cancer (CRC) and to compare their prognosis with those of older patients Methods: We retrospectively reviewed the medical records of patients who underwent surgery for stage 0-III CRC at four university-affiliated hospitals between January 2011 and December 2020. The patients were divided into two groups, the young adult group (≤45 years) and the older group (>45 years).

RESULTS

Of 1992 patients, 93 (4.6%) were young adults and 1899 (95.3%) were older patients. Young patients showed more symptoms (p = 0.014) and more poorly or undifferentiated adenocarcinoma (p = 0.047) than older patients. The young adult patients were more likely to receive adjuvant chemotherapy (p < 0.001) and multidrug agents (p = 0.029), and less likely to cease chemotherapy (p = 0.037). The five-year RFS (recurrence-free survival) rate was better in the young adults than in the older patients (p = 0.009). In the multivariable analysis, young age was a significant prognostic factor for better RFS (p = 0.015).

CONCLUSIONS

Young patients with CRC had more symptoms, aggressive histological features than older patients. They received more multidrug agents and discontinued chemotherapy less often, resulting in better prognosis.

The mortality risk in patients with early onset colorectal cancer: the role of comorbidities

The global incidence of early-onset colorectal cancer (EO-CRC) is increasing. Although the mortality rate is relatively stable, some comorbidities have been associated with a higher mortality rate. This study estimated the mortality risk in patients with EO-CRC with various comorbidities using real-world data to identify the high-risk group using Cox proportional regression for overall and cancer-specific mortality. The incidence rate of EO-CRC significantly increased from 6.04 per 100,000 population in 2007 to 12.97 per 100,000 population in 2017. The five-year overall mortality rate was 101.50 per 1000 person year and the cancer-specific mortality rate was 94.12 per 1000 person year. Patients with cerebrovascular disease (CVD) had a higher mortality risk (hazard ratio (HR): 1.68; 95% confidence interval (CI): 1.25-2.28; p=0.0007). After subgroup analyses based on age, sex, clinical stage, and treatment type, patients with CVD had a higher overall mortality risk compared to non-CVD patients, except for patients undergoing surgery and chemotherapy. Patients with chronic kidney disease had a higher mortality risk in the early clinical stages (HR: 2.31; 95% CI: 1.08-4.96; p=0.0138). Patients who underwent radiotherapy had a higher overall mortality risk (HR: 1.38; 95% CI: 1.04-1.85; p=0.0285) than those without liver disease. Identifying specific comorbidity mortality risks in patients with EO-CRC allows for risk stratification when screening target groups and may lower disease mortality.

Low MTUS1 Protein Expression Is Associated with Poor Survival in Patients with Colorectal Adenocarcinoma

Introduction: Microtubule-associated tumor suppressor 1 (MTUS1) is a novel tumor suppressor protein involved in cell proliferation, migration, and tumor growth. MTUS1 is thought to be downregulated in various human cancers and associated with poor prognosis. We evaluated the clinicopathologic significance and prognostic value of MTUS1 in colorectal adenocarcinoma. Methods: Immunohistochemical staining for MTUS1 was performed on tissue microarrays of 393 colorectal adenocarcinoma cases, and MTUS1 staining was classified into high- and low-expression groups. Then, we investigated the correlations between MTUS1 protein expression and various clinicopathological parameters and patient survival. Results: MTUS1 protein was expressed at various grade levels in the cytoplasm of tumor cells, which showed loss or decreased expression of MTUS1. A total of 253 cases (64.4%) were classified into the low MTUS1 protein expression group and 140 cases (35.6%) into the high MTUS1 expression group. A low level of MTUS1 protein significantly correlated with tumor size (p = 0.047), histological grade (p < 0.001), lymphovascular invasion (p < 0.001), perineural invasion (p = 0.047), and lymph node metastasis (p < 0.001). Survival analyses showed that patients with low MTUS1 protein expression had worse overall survival (p = 0.007, log-rank test) and worse recurrence-free survival (p = 0.019, log-rank test) than those with high MTUS1 expression. Conclusions: Low MTUS1 protein expression is associated with adverse clinicopathological characteristics and poor survival outcomes in patients with colorectal adenocarcinoma. These results suggest that MTUS1 functions as a tumor suppressor in colorectal adenocarcinoma and could be a potential prognostic biomarker.

An ecological study of obesity-related cancer incidence trends in Australia from 1983 to 2017

BACKGROUND

Overweight and obesity is a growing public health issue as it contributes to the future burden of obesity-related diseases, including cancer, especially in high-income countries. In Australia, 4.3% of all cancers diagnosed in 2013 were attributable to overweight and obesity. Our aim was to examine Australian age-specific incidence trends over the last 35 years for obesity-related cancers based on expert review (colorectal, liver, gallbladder, pancreas, breast in postmenopausal women, uterine, ovary, kidney, thyroid, and multiple myeloma) individually and pooled.

METHODS

Australian incidence data for 10 obesity-related cancers among people aged 25-84 years, diagnosed from 1983 to 2017, were obtained from the Australian Cancer Database. We used age-period-cohort modelling and joinpoint analysis to assess trends, estimating incidence rate ratios (IRR) by birth-cohort for each individual cancer and pooled, and the annual percentage change. The analyses were also conducted for non-obesity-related cancers over the same period.

FINDINGS

The total number of cancers where some proportion is obesity-related, diagnosed from 1983-2017, was 1,005,933. This grouping was 34.7% of cancers diagnosed. The IRR of obesity-related cancers increased from 0.77 (95% CI 0.73, 0.81) for the 1903 birth-cohort to 2.95 (95% CI 2.58, 3.38) for the recent 1988 cohort relative to the 1943 cohort. The IRRs of non-obesity related cancers were stable with non-significant decreases in younger cohorts. These trends were broadly similar across sex and age groups.

INTERPRETATION

The incidence of obesity-related cancers in Australia has increased by birth-cohort across all age-groups, which should be monitored. Obesity, a public health epidemic, needs to be addressed through increased awareness, policy support and evidence-based interventions.

FUNDING

This research received no specific funding.

The global, regional, and national early-onset colorectal cancer burden and trends from 1990 to 2019: results from the Global Burden of Disease Study 2019

PURPOSE

The incidence of early-onset colorectal cancer (EO-CRC), which occurs in people under age 50, has been increasing annually. The aim of this study was to provide an up-to-date estimate of the global EO-CRC burden.

METHODS

We used Global Burden of Disease Study data and methodologies to describe changes in the EO-CRC burden from 1990 to 2019, including incidence, prevalence, mortality, and disability-adjusted life years (DALYs). The driving factors for cancer burden variation were further analyzed using decomposition analysis. Frontier analysis was used to visually demonstrate the potential for burden reduction in each country or region based on their development levels.

RESULTS

The global EO-CRC incidence more than doubled, increasing from 95,737 (95% uncertainty interval (UI): 90,838-101.042) /100,000 in 1990 to 226,782 (95% UI: 207,495-248,604) /100,000 in 2019. Additionally, related deaths increased from 50,997 (95% UI: 47,692-54,410) /100,000 to 87,014 (95% UI: 80,259-94,339) /100,000, and DALYs increased from 256,1842 (95% UI: 239,4962-2,735,823) /100,000 to 4,297,573 (95% UI: 3,965,485-4,650,790) /100,000. Regarding age-standardized rates, incidence and prevalence increased significantly, while mortality and DALYs rate were basically unchanged. Decomposition analysis showed a significant increase in DALYs in the middle sociodemographic index (SDI) quintile region, in which aging and population growth played a major driving role. Frontier analysis showed that countries or regions with a higher SDI quintile tend to have greater improvement potential.

CONCLUSION

The current EO-CRC burden was found to be the greatest in the high-middle SDI quintile region and East Asia, which may need to adjust screening guidelines accordingly and introduce more effective interventions.

Faecal immunochemical testing (FIT) in patients with signs or symptoms of suspected colorectal cancer (CRC): a joint guideline from the Association of Coloproctology of Great Britain and Ireland (ACPGBI) and the British Society of Gastroenterology (BSG)

Faecal immunochemical testing (FIT) has a high sensitivity for the detection of colorectal cancer (CRC). In a symptomatic population FIT may identify those patients who require colorectal investigation with the highest priority. FIT offers considerable advantages over the use of symptoms alone, as an objective measure of risk with a vastly superior positive predictive value for CRC, while conversely identifying a truly low risk cohort of patients. The aim of this guideline was to provide a clear strategy for the use of FIT in the diagnostic pathway of people with signs or symptoms of a suspected diagnosis of CRC. The guideline was jointly developed by the Association of Coloproctology of Great Britain and Ireland/British Society of Gastroenterology, specifically by a 21-member multidisciplinary guideline development group (GDG). A systematic review of 13 535 publications was undertaken to develop 23 evidence and expert opinion-based recommendations for the triage of people with symptoms of a suspected CRC diagnosis in primary care. In order to achieve consensus among a broad group of key stakeholders, we completed an extended Delphi of the GDG, and also 61 other individuals across the UK and Ireland, including by members of the public, charities and primary and secondary care. Seventeen research recommendations were also prioritised to inform clinical management.

Prevalence and risk of colorectal polyps among the Korean population under 50 years

Colorectal cancer is a common cancer; generally, adults aged ≥ 50 years are screened using stool occult blood tests and colonoscopy. However, colorectal adenoma and cancer have been found in patients under the aged of 50, and studies on characteristics and risk factors in young patients are lacking. We evaluated the prevalence and risk factors of colorectal adenoma and cancer in young adults aged under 50 years. We retrospectively analyzed 570 individuals aged under 50 years who underwent colonoscopy at the Haeundae Paik Hospital, Korea, from January to June 2018. Logistic regression model was used to identify the risk factors for colorectal adenoma and colorectal cancer. The prevalence of colorectal adenoma in group of 19-29 years was 3.2% (1 of 31), 30-39 years was 13.8% (30 of 217) and in the group of 40-49 years was 21.1% (68 of 322) (P = .009). In multivariable analysis, age over 45 years (adjusted odds ratio [OR], 1.941; 95% confidence interval [CI], 1.187-3.172; P = .008) and male sex (adjusted OR, 1.711; 95% CI, 1.044-2.806; P = .033) were independent risk factors for colorectal neoplasia including cancer. The prevalence of colorectal adenoma increases as the age increased in young adults under 50 years of age, especially after the age of 45 years, the risk of colorectal neoplasia increases; hence, early screening should be considered before the age of 50 years.

Construction of a miRNA-mRNA Network Related to Exosomes in Colon Cancer

Background

The competing endogenous RNA (CeRNA) network plays important roles in the occurrence and development of colon cancer. This research is aimed at constructing a miRNA-mRNA network associated with exosomes in colon cancer.

Methods

We explored the GEO database and then analyzed the RNAs of 722 samples to obtain differentially expressed miRNAs (DEMs) and mRNAs (DEGs) alongside the progress of colon cancer. Next, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of DEM target genes and DEGs were performed. In addition, a miRNA-mRNA network related to exosomes in colon cancer was constructed based on DEMs and DEGs. Finally, the expression of miRNA and mRNA in the network was verified by GEPIA2 on the base of TCGA database.

Results

Through our analysis, 19 DEMs (17 up and 2 down) and 1672 DEGs (954 up and 718 down) were screened. The GO and KEGG results show that these DEGs were mainly enriched in ribonucleoprotein complex biogenesis, noncoding RNA metabolic process, cell-substrate junction, cadherin binding, transcription coregulator activity, and regulation of the human T-cell leukemia virus 1 infection-related pathway. Besides, a miRNA-mRNA network, including 4 miRNAs (hsa-miR-623, hsa-miR-320c, hsa-miR-486-5p, and hsa-miR-1290) and 7 mRNAs (GNAI1, CADM1, PGRMC2, etc.), was constructed. Three of these seven mRNAs were downregulated in colon cancer. Ultimately, the GNAI1, CADM1, and PGRMC2 expression levels were verified by TCGA database.

Conclusions

This study reveals the network relationship between colon cancer exosome-derived miRNA and targeted mRNA. It deepens our understanding of new molecular mechanisms and pathways that may play a role in the occurrence and metastasis of colon cancer.

Global, regional, and national burden of colorectal cancer and its risk factors, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019

BACKGROUND

Colorectal cancer is the third leading cause of cancer deaths worldwide. Given the recent increasing trends in colorectal cancer incidence globally, up-to-date information on the colorectal cancer burden could guide screening, early detection, and treatment strategies, and help effectively allocate resources. We examined the temporal patterns of the global, regional, and national burden of colorectal cancer and its risk factors in 204 countries and territories across the past three decades.

METHODS

Estimates of incidence, mortality, and disability-adjusted life years (DALYs) for colorectal cancer were generated as a part of the Global Burden of Diseases, Injuries and Risk Factors Study (GBD) 2019 by age, sex, and geographical location for the period 1990-2019. Mortality estimates were produced using the cause of death ensemble model. We also calculated DALYs attributable to risk factors that had evidence of causation with colorectal cancer.

FINDINGS

Globally, between 1990 and 2019, colorectal cancer incident cases more than doubled, from 842 098 (95% uncertainty interval [UI] 810 408-868 574) to 2·17 million (2·00-2·34), and deaths increased from 518 126 (493 682-537 877) to 1·09 million (1·02-1·15). The global age-standardised incidence rate increased from 22·2 (95% UI 21·3-23·0) per 100 000 to 26·7 (24·6-28·9) per 100 000, whereas the age-standardised mortality rate decreased from 14·3 (13·5-14·9) per 100 000 to 13·7 (12·6-14·5) per 100 000 and the age-standardised DALY rate decreased from 308·5 (294·7-320·7) per 100 000 to 295·5 (275·2-313·0) per 100 000 from 1990 through 2019. Taiwan (province of China; 62·0 [48·9-80·0] per 100 000), Monaco (60·7 [48·5-73·6] per 100 000), and Andorra (56·6 [42·8-71·9] per 100 000) had the highest age-standardised incidence rates, while Greenland (31·4 [26·0-37·1] per 100 000), Brunei (30·3 [26·6-34·1] per 100 000), and Hungary (28·6 [23·6-34·0] per 100 000) had the highest age-standardised mortality rates. From 1990 through 2019, a substantial rise in incidence rates was observed in younger adults (age <50 years), particularly in high Socio-demographic Index (SDI) countries. Globally, a diet low in milk (15·6%), smoking (13·3%), a diet low in calcium (12·9%), and alcohol use (9·9%) were the main contributors to colorectal cancer DALYs in 2019.

INTERPRETATION

The increase in incidence rates in people younger than 50 years requires vigilance from researchers, clinicians, and policy makers and a possible reconsideration of screening guidelines. The fast-rising burden in low SDI and middle SDI countries in Asia and Africa calls for colorectal cancer prevention approaches, greater awareness, and cost-effective screening and therapeutic options in these regions.

FUNDING

Bill & Melinda Gates Foundation.

Early detection of colorectal neoplasia: application of a blood-based serological protein test on subjects undergoing population-based screening

BACKGROUND

Blood-based biomarkers used for colorectal cancer screening need to be developed and validated in appropriate screening populations. We aimed to develop a cancer-associated protein biomarker test for the detection of colorectal cancer in a screening population.

METHODS

Participants from the Danish Colorectal Cancer Screening Program were recruited. Blood samples were collected prior to colonoscopy. The cohort was divided into training and validation sets. We present the results of model development using the training set. Age, sex, and the serological proteins CEA, hsCRP, TIMP-1, Pepsinogen-2, HE4, CyFra21-1, Galectin-3, ferritin and B2M were used to develop a signature test to discriminate between participants with colorectal cancer versus all other findings at colonoscopy.

RESULTS

The training set included 4048 FIT-positive participants of whom 242 had a colorectal cancer. The final model for discriminating colorectal cancer versus all other findings at colonoscopy had an AUC of 0.70 (95% CI: 0.66-0.74) and included age, sex, CEA, hsCRP, HE4 and ferritin.

CONCLUSION

The performance of the biomarker signature in this FIT-positive screening population did not reflect the positive performance of biomarker signatures seen in symptomatic populations. Additional biomarkers are needed if the serological biomarkers are to be used as a frontline screening test.

Epidemiological trends of gallbladder cancer in Australia between 1982 to 2018: A population-based study utilizing the Australian Cancer Database

Backgrounds/Aims

Gallbladder cancer (GBC) is a rare neoplasm. The epidemiology of GBC has not been updated in Australia for over five decades.

Methods

Data of all Australian patients diagnosed with GBC at any age from 1982 to 2018 were identified from the Australian Cancer Database. Age-standardized rates were calculated and joinpoint analysis was performed to ascertain the trends of incidence and mortality of GBC.

Results

Between 1982 and 2018, there were 22,745 cases of GBC and 11,054 GBC-related deaths in Australia. There were three distinct periods showing changed incidence. Period 1 (1982–1995) was stable. Period 2 (1996–2006) showed reduced incidence in females (3.6 to 2.8/100,000; p < 0.01) and all Australians (3.7 to 2.8/100,000, p < 0.01). Period 3 (2006–2017) demonstrated significantly increased incidence in all groups (males: 2.7 to 4.0/100,000, p < 0.01; females: 2.8 to 3.5/100,000, p < 0.01; all Australians: 2.8 to 3.7/100,000, p < 0.01). Incidence between females and males had declined from 1.10 : 1 in 1982 to 0.87 : 1 in 2017. There was a 71% reduction in mortality (3.1 to 0.9/100,000; p < 0.01). Median age at diagnosis increased from 69.7 to 74.3 years for females and from 67.2 to 73.3 years for males. Increasing incidence in the 6th to 8th decade of life in males, compared to previous years, was noted.

Conclusions

Incidence, mortality, sex, and age of GBC have significantly changed in Australia since 1982. Rising incidence of GBC in Australia warrants further investigation.

The Association of Microbiome Dysbiosis With Colorectal Cancer

Many studies have been conducted to identify the causative organisms in colorectal cancer (CRC) and compare the microbiota of healthy individuals and those with CRC. The pathways by which the microbiota promotes CRC development are not yet fully understood. The hypothesized mechanisms include damage to the DNA, production of carcinogenic metabolites, and promotion of chronic inflammation. In a state of dysbiosis, the gut loses protective bacteria and is enriched with pathogenic and cancer-promoting bacteria, which promotes functions associated with cancer such as angiogenesis, loss of apoptosis, and cell proliferation. We have established a strong link between microbiota dysbiosis and certain species of bacteria and even viruses involved in tumorigenesis. In this review, we look at some of the major identified species and how they are related to CRC. Future research should include and even focus on mycobiome and virome on CRC development. Due to the diversity of the gut microbiome, there is a high possibility that the gain and loss of bacteria and their metabolic functions lead to CRC.

Clinical and molecular profile of young adults with early-onset colorectal cancer: Experience from four Australian tertiary centers

BACKGROUND

Patients with early-onset colorectal cancer (EO-CRC) have unique characteristics. Contemporary data on the pathological and molecular features, and survival of EO-CRC are limited in the Australian context.

AIM

To determine the demographic, histopathological and molecular characteristics of adults with EO-CRC, and their survival.

METHODS

We conducted a retrospective study of adults aged 18-49 years with EO-CRC who were referred to the Illawarra Shoalhaven Local Health District, South Eastern Sydney Local Health District and Royal North Shore Hospital in New South Wales, Australia, between 2014 and 2018.

RESULTS

Of 257 patients included, 94 (37%) patients presented with de novo metastatic CRC, 80% patients had near-average risk family history and 89% had a symptomatic presentation. In 159 patients with nonmetastatic disease at diagnosis, stage III disease (OR 3.88 [95% CI: 1.13-13.3]; p = .03) and the presence of perineural invasion (PNI) (OR 6.63 [95% CI: 2.21-19.84]; p = .001) were risk factors associated with the development of metastatic disease. Among 94 patients with de novo metastatic disease, 43 (43%) and 12 (14%) patients harbored a KRAS or BRAF V600E mutation, respectively. The median overall survival was 29.6 months (95% CI: 20.4-38.7). BRAF mutation was associated with inferior survival (HR 3.00 [95% CI: 1.30-6.94]; p = .01).

CONCLUSION

The prevalence of KRAS and BRAF mutations in our cohort is similar to the overseas experience. Stage III disease at diagnosis, presence of PNI and BRAF mutation are adverse prognostic indicators. A better understanding of the molecular landscape is needed for this patient cohort, so as to better tailor prevention strategies, screening and treatment pathways.

Gastrointestinal Adenocarcinoma Incidence and Survival Trends in South Australia, 1990-2017

BACKGROUND & AIMS

Globally, there has been a concerning rise in the incidence of young-onset cancers. The aim of this study was to provide trends in the incidence and survival of gastrointestinal adenocarcinomas (oesophagus, stomach, pancreas, and colorectal) in South Australia over a 27-year period.

METHODS

This is a cross-sectional analysis of a prospective longitudinal database including all cases of gastrointestinal adenocarcinomas prospectively reported to the South Australian (State) Cancer Registry from 1990 to 2017.

RESULTS

A total of 28,566 patients diagnosed with oesophageal, stomach, pancreatic, or colorectal adenocarcinoma between 1990 and 2017 were included in the study. While the overall incidence for gastrointestinal adenocarcinomas in individuals >50 years has decreased since 2000 (IRR of 0.97 (95% CI 0.94-1.00; p = 0.06)) compared to 1990-1999, the rate amongst individuals aged 18-50 has significantly increased (IRR 1.41 (95% CI 1.27-1.57; p < 0.001)) during the same reference time period. Although noted in both sexes, the rate of increase in incidence was significantly greater in males (11.5 to 19.7/100,000; p < 0.001). The overall survival from adenocarcinomas across all subsites improved in the >50-year cohort in the last decade (HR 0.89 (95% CI 0.86-0.93; p < 0.001)) compared to 1990-1999. In individuals aged 18-50 years, there has only been a significant improvement in survival for colorectal cancer (HR 0.82 (95% CI 0.68-0.99; p < 0.04)), but not the other subsites. A lower overall survival was noted for males in both age cohorts (18-50 years-HR 1.24 (95% CI 1.09-1.13; p < 0.01) and >50 years-HR 1.13 (95% CI 1.10-1.16; p < 0.001), respectively) compared to females.

CONCLUSIONS

This study from South Australia demonstrates a significant increase in young-onset gastrointestinal adenocarcinomas over the last 28 years, with a greater increase in the male sex. The only significant improvement in survival in this cohort has been noted in colorectal cancer patients.

Trends in colon cancer incidence in young and older adults in Macva region (Serbia)

Objectives: Our goal was to conduct the first survey and screening of colon cancer incidence trends in the Macva district, Serbia. Methods: Age-specific incidence of colon cancer among the > 20 years old adults that were diagnosed from 2006-2015 was analyzed using data from Cancer Registries of the Sabac Public Health Institute and Public Health Institute of Serbia. Linear model of the incidence rates and annual change in age-standardized incidence rates, by sex and age were presented. Standardized incidence ratio, based on average age-specific incidence rates of colon cancer for Sabac municipality and Central Serbia was calculated. Results: Based on the results from our study, colon cancer incidence in Sabac municipality increased in males and females in the last ten years. Risk of developing colon cancer in males and females, calculated by standardized rates ratios was 1.5 and 1.3, respectively. Linear, rising trend for age-standardized incidence rates in the population of Sabac compared to other municipalities in the Macva district was recorded. Furthermore, standardized incidence ratios for both females and males were higher compared to data from Central Serbia (28% and 22%, respectively). Conclusion: Our study revealed increased colon cancer incidence, with a linear increase of colon cancers in young males and also in > 50 years old population.

Colorectal cancer patients in a tertiary hospital in Indonesia: Prevalence of the younger population and associated factors

BACKGROUND

An increasing trend in colorectal cancer (CRC) occurring at younger ages has been observed worldwide, even though incidence is declining in the general population. Most currently available guidelines still recommend CRC screening for older populations, despite an alarming rise in early-onset CRC incidence. Risk stratification is necessary to further determine the population most at risk for early-onset CRC. However, epidemiological data on related clinical characteristics and potential risk factors, especially in developing countries, have not been widely reported.

AIM

To investigate the prevalence, demographics, clinicopathologic features, and associated factors of young-onset CRC patients in a tertiary hospital in Indonesia.

METHODS

Patients undergoing colonoscopy examination between 2008 and 2019, yielding a diagnosis of CRC were identified from medical records. The subjects were classified into two groups according to their age at diagnosis, namely early-onset (18-49 years old) and late-onset (≥ 50-years-old). Demographic data, characteristics, and risk factors of both onset age groups were evaluated using the chi-square and Fisher's exact test.

RESULTS

Among 495 CRC patients confirmed by histopathology, 205 (41.4%) were classified as early-onset and 290 (58.6%) as late-onset. Most subjects in the early-onset CRC group were male (53.7%), with 89.8% displaying adenocarcinoma histopathology. A majority (78%) of the early-onset CRC patients had left-sided tumors, with the rectum (41%) and rectosigmoid (17.6%) being the most common sites. Abdominal pain was the most frequent symptom in the early-onset CRC patients (55.6%), which was significantly higher than that in the late-onset CRC patients (43.8%, P < 0.05). Early-onset CRC cases were more likely to be underweight (34.6% vs 20.0%, P < 0.001) compared to late-onset CRC cases. The proportion of subjects with suspected hereditary nonpolyposis colorectal cancer (HNPCC) was also higher in the early-onset CRC group than in the late-onset age group (9.3% vs 4.1%, P < 0.05). However, no difference was observed in the parental or family histories of CRC cases.

CONCLUSION

Early-onset CRC patients were more likely to have abdominal pain, underweight status, and HNPCC suspicion than late-onset CRC patients.

Finding the needle in the haystack: the diagnostic accuracy of the faecal immunochemical test for colorectal cancer in younger symptomatic patients

AIM

Detection of early onset colorectal cancer is challenging, and remains a rare diagnosis amongst younger people with gastrointestinal symptoms. We investigated whether faecal immunochemical testing (FIT) could identify younger patients at higher risk of colorectal cancer or serious bowel disease including colorectal cancer, inflammatory bowel disease or advanced adenomas.

METHODS

A subgroup analysis was performed of symptomatic patients under 50 years of age (<50) from the NICE FIT study, a multicentre, prospective diagnostic accuracy study of FIT conducted between October 2017 and December 2019. The diagnostic accuracy of FIT for colorectal cancer and serious bowel disease was investigated in younger patients at different faecal haemoglobin (f-Hb) cut-offs of 2, 10 and 150 µg blood/g faeces (µg/g).

RESULTS

Early onset colorectal cancer was diagnosed in 1.5% (16/1103) of younger symptomatic patients. The sensitivity of FIT for younger patients aged <50 was 87.5% (95% CI 61.7%-98.4%), 81.3% (54.4%-96.0%) and 68.8% (41.3%-89.0%) at f-Hb cut-offs of 2, 10 and 150 µg/g, respectively. The positive predictive value for colorectal cancer increased from 4.2% (2.3%-6.9%) to 11.5% (5.9%-19.6%) at cut-offs of 2 and 150 µg/g, while the positive predictive value for serious bowel disease increased from 31.3% (26.3%-36.5%) to 65.6% (55.2%-75.0%) at the same cut-offs. The negative predictive value of FIT for colorectal cancer remained above 99.5% at all cut-offs.

CONCLUSION

Detectable f-Hb on FIT in symptomatic younger patients may indicate referral for investigation of colorectal cancer and serious bowel disease.

Rectal Cancer in Adolescent and Young Adult Patients: Pattern of Clinical Presentation and Case-Matched Comparison of Outcomes

BACKGROUND

Rectal cancer in adolescents and young adults (age ≤39) is increasing. Early diagnosis is a challenge in this subset of patients.

OBJECTIVE

This study aims to analyze the presentation pattern and outcomes of sporadic rectal cancer in adolescents and young adults.

DESIGN

This is a retrospective study.

SETTING

This study was conducted at 3 European tertiary centers.

PATIENTS

Data on adolescents and young adults operated on for sporadic rectal cancer (January 2008 through October 2019) were analyzed. To compare outcomes, adolescents and young adults were matched to a group of patients aged ≥40 operated on during the same period.

MAIN OUTCOME MEASURES

The primary outcomes measured were clinical presentation and long-term outcomes.

RESULTS

Sporadic rectal cancers occurred in 101 adolescents and young adults (2.4%; mean age, 33.5; range, 18-39); 51.5% were male, and a smoking habit was reported by 17.8% of patients. The rate of a family history for colorectal cancer was 25.7%, and of these patients, 24.7% were obese. Diagnosis based on symptoms was reported in 92.1% patients, and the mean time from first symptoms to diagnosis was 13.7 months. The most common symptom at diagnosis was rectal bleeding (68.8%), and 12% and 34% of the adolescents and young adults presented with locally advanced or metastatic disease at diagnosis. Consequently, 68.3% and 62.4% adolescents and young adults received neoadjuvant and adjuvant treatments. The rate of complete pathological response was 24.1%; whereas 38.6% patients had stage IV disease, and 93.1% were microsatellite stable. At a mean follow-up of 5 years, no difference in cancer-specific survival, but a lower disease-free survival was reported in adolescents and young adults (p < 0.0001) vs the matched group. Adolescents and young adults with stages I to II disease had shorter cancer-specific survival and disease-free survival (p = 0.006; p < 0.0001); with stage III disease, they had a shorter disease-free survival (p = 0.01).

LIMITATIONS

This study was limited by its observational, retrospective design.

CONCLUSIONS

The significantly delayed diagnosis in adolescents and young adults may have contributed to the advanced disease at presentation and lower disease-free survival, even at earlier stages, suggesting a higher metastatic potential than in older patients. See Video Abstract at http://links.lww.com/DCR/B537.

CNCER DE RECTO EN PACIENTES ADOLESCENTES Y ADULTOS JVENES CUADRO DE PRESENTACIN CLNICA Y COMPARACIN DE DESENLACES POR CASOS EMPAREJADOS

ANTECEDENTES:El cáncer de recto en adolescentes y adultos jóvenes (edad ≤ 39) está aumentando. El diagnóstico temprano es un desafío en este subgrupo de pacientes.OBJETIVO:Analizar el cuadro de presentación y los desenlaces en adolescentes y adultos jóvenes con cáncer de recto esporádico.DISEÑO:Estudio retrospectivo.ÁMBITO:Tres centros europeos de tercer nivel.PACIENTES:Se analizaron los datos de adolescentes y adultos jóvenes operados de cáncer de recto esporádico (enero de 2008 - octubre de 2019). Para comparar los desenlaces se emparejó a adolescentes y adultos jóvenes con un grupo de pacientes mayores de 40 años operados en el mismo período de tiempo.PRINCIPALES VARIABLES ANALIZADAS:Cuadro clínico, resultados a largo plazo.RESULTADOS:Los cánceres de recto esporádicos en adolescentes y adultos jóvenes fueron 101 (2,4%, edad media: 33,5, rango 18-39). El 51,5% eran hombres, el 17,8% de los pacientes fumaba. El 25,7% tentía antecedentes familiares de cáncer colorrectal. El 24,7% eran obesos. El diagnóstico con base en los síntomas se informó en el 92,1% de los pacientes, el tiempo promedio desde los primeros síntomas hasta el diagnóstico fue de 13,7 meses. El síntoma más común en el momento del diagnóstico fue el sangrado rectal (68,8%). 12% y 34% de adolescentes y adultos jóvenes presentaron enfermedad localmente avanzada o metastásica en el momento del diagnóstico. Por lo tanto, el 68,3% y el 62,4% de adolescentes y adultos jóvenes recibieron neoadyuvancia y adyuvancia. La tasa de respuesta patológica completa fue del 24,1%; mientras que el 38,6% estaban en estadio IV. El 93,1% eran microsatelite estable. Con una media de seguimiento de 5 años, no se observaron diferencias en la sobrevida específica del cáncer, pero se informó una menor sobrevida libre de enfermedad en adolescentes y adultos jóvenes (p <0,0001) frente al grupo emparejado. Los adolescentes y adultos jóvenes en estadios I-II tuvieron una sobrevida específica por cáncer y una sobrevida libre de enfermedad más corta (p = 0,006; p <0,0001); el estadio III tuvo una sobrevida libre de enfermedad más baja (p = 0,01).LIMITACIONES:Diseño observacional y retrospectivo.CONCLUSIONES:El diagnóstico notablemente demorado en adolescentes y adultos jóvenes puede contribuir a la presentación de una enfermedad avanzada y a una menor sobrevida libre de enfermedad, incluso en estadios más tempranas, lo cual implica un mayor potencial metastásico en comparación con pacientes mayores. Consulte Video Resumen en http://links.lww.com/DCR/B537.

Whole Grain Intakes Are Associated with Healthcare Cost Savings Following Reductions in Risk of Colorectal Cancer and Total Cancer Mortality in Australia: A Cost-of-Illness Model

Whole grain consumption has been associated with the reduced risk of several chronic diseases with significant healthcare monetary burden, including cancer. Colorectal cancer (CRC) is one of the most common cancers globally, with the highest rates reported in Australia. Three servings of whole grains provide a 15% reduction in total cancer and 17% reduction in CRC risk; however, 70% of Australians fall short of this level of intake. The aim of this study was to assess the potential savings in healthcare costs associated with reductions in the relative risk of CRC and total cancer mortality following the whole grain Daily Target Intake (DTI) of 48 g in Australia. A three-step cost-of-illness analysis was conducted using input parameters from: (1) estimates of current and targeted whole grain intakes among proportions (5%, 15%, 50%, and 100%) of the Australian adult (≥20 years) population; (2) estimates of reductions in relative risk (with 95% confidence intervals) of CRC and total cancer mortality associated with specific whole grain intake from meta-analysis studies; and (3) estimates of annual healthcare costs of CRC and all cancers from disease expenditure national databases. A very pessimistic (5% of population) through to universal (100% of population) adoption of the recommended DTI in Australia were shown to potentially yield savings in annual healthcare costs equal to AUD 1.9 (95% CI 1.2-2.4) to AUD 37.2 (95% CI 24.1-48.1) million for CRC and AUD 20.3 (95% CI 12.2-27.0) to AUD 405.1 (95% CI 243.1-540.1) million for total cancers. As treatment costs for CRC and other cancers are increasing, and dietary measures exchanging whole grains for refined grains are not cost preclusive nor does the approach increase energy intake, there is an opportunity to facilitate cost-savings along with reductions in disease for Australia. These results suggest specific benefits of encouraging Australians to swap refined grains for whole grains, with greater overall adherence to suggestions in dietary guidelines.

Younger age at onset of colorectal cancer is associated with increased patient's delay

AIM

This study aimed to investigate if younger age at diagnosis of colorectal cancer was associated with a diagnostic delay. The secondary objective was to evaluate if symptomatology varied with age.

METHOD

The study population consisted of the cohorts from two prospective multicentre studies conducted in Sweden and Denmark, the QoLiRECT and QoLiCOL studies. These studies investigated the quality of life in patients with colorectal cancer. Participants responded to the validated questionnaires used to extract information on patient's and doctor's delay as well as first presenting symptoms. Clinical variables were retrieved from the Swedish Colorectal Cancer Registry and the Danish Colorectal Cancer Group Database.

RESULTS

2574 patients were included, 1085 from QoLiRECT and 1489 from QoLiCOL. The probability of an increased patient's delay was higher when age decreased by 10 years (the SD in both QoLiRECT and QoLiCOL), adjusted OR 1.19 (95%CI: 1.10; 1.30), p < 0.001. A similar effect was found for doctor's delay, but the age effect was smaller in this case, adjusted OR 1.05 (95%CI: 0.97; 1.15), p = 0.177. When the age effect was analysed non-linearly, an increased probability of a delay was seen for patients from around 60 years and below. Younger patients were equally or more likely to report the symptoms of blood in stool, diarrhoea, constipation, mucus in faeces, faecal urgency, faecal emptying difficulties and pain compared to older patients.

CONCLUSION

Younger patients were more likely to have an increased patient's delay, probably contributing to a delayed diagnosis of colorectal cancer. Symptomatology at diagnosis was similar irrespective of age.

Nongenetic Determinants of Risk for Early-Onset Colorectal Cancer

Background

Incidence of early-onset (younger than 50 years of age) colorectal cancer (CRC) is increasing in many countries. Thus, elucidating the role of traditional CRC risk factors in early-onset CRC is a high priority. We sought to determine whether risk factors associated with late-onset CRC were also linked to early-onset CRC and whether association patterns differed by anatomic subsite.

Methods

Using data pooled from 13 population-based studies, we studied 3767 CRC cases and 4049 controls aged younger than 50 years and 23 437 CRC cases and 35 311 controls aged 50 years and older. Using multivariable and multinomial logistic regression, we estimated odds ratios (ORs) and 95% confidence intervals (CIs) to assess the association between risk factors and early-onset CRC and by anatomic subsite.

Results

Early-onset CRC was associated with not regularly using nonsteroidal anti-inflammatory drugs (OR = 1.43, 95% CI = 1.21 to 1.68), greater red meat intake (OR = 1.10, 95% CI = 1.04 to 1.16), lower educational attainment (OR = 1.10, 95% CI = 1.04 to 1.16), alcohol abstinence (OR = 1.23, 95% CI = 1.08 to 1.39), and heavier alcohol use (OR = 1.25, 95% CI = 1.04 to 1.50). No factors exhibited a greater excess in early-onset compared with late-onset CRC. Evaluating risks by anatomic subsite, we found that lower total fiber intake was linked more strongly to rectal (OR = 1.30, 95% CI = 1.14 to 1.48) than colon cancer (OR = 1.14, 95% CI = 1.02 to 1.27; P = .04).

Conclusion

In this large study, we identified several nongenetic risk factors associated with early-onset CRC, providing a basis for targeted identification of those most at risk, which is imperative in mitigating the rising burden of this disease.

DNA Methylation Signatures and the Contribution of Age-Associated Methylomic Drift to Carcinogenesis in Early-Onset Colorectal Cancer

We investigated aberrant DNA methylation (DNAm) changes and the contribution of ageing-associated methylomic drift and age acceleration to early-onset colorectal cancer (EOCRC) carcinogenesis. Genome-wide DNAm profiling using the Infinium HM450K on 97 EOCRC tumour and 54 normal colonic mucosa samples was compared with: (1) intermediate-onset CRC (IOCRC; diagnosed between 50-70 years; 343 tumour and 35 normal); and (2) late-onset CRC (LOCRC; >70 years; 318 tumour and 40 normal). CpGs associated with age-related methylation drift were identified using a public dataset of 231 normal mucosa samples from people without CRC. DNAm-age was estimated using epiTOC2. Common to all three age-of-onset groups, 88,385 (20% of all CpGs) CpGs were differentially methylated between tumour and normal mucosa. We identified 234 differentially methylated genes that were unique to the EOCRC group; 13 of these DMRs/genes were replicated in EOCRC compared with LOCRCs from TCGA. In normal mucosa from people without CRC, we identified 28,154 CpGs that undergo ageing-related DNAm drift, and of those, 65% were aberrantly methylated in EOCRC tumours. Based on the mitotic-based DNAm clock epiTOC2, we identified age acceleration in normal mucosa of people with EOCRC compared with normal mucosa from the IOCRC, LOCRC groups (p = 3.7 × 10-16) and young people without CRC (p = 5.8 × 10-6). EOCRC acquires unique DNAm alterations at 234 loci. CpGs associated with ageing-associated drift were widely affected in EOCRC without needing the decades-long accrual of DNAm drift as commonly seen in intermediate- and late-onset CRCs. Accelerated ageing in normal mucosa from people with EOCRC potentially underlies the earlier age of diagnosis in CRC carcinogenesis.

Maximal voluntary ventilation and forced vital capacity of pulmonary function are independent prognostic factors in colorectal cancer patients: A retrospective study of 2323 cases in a single-center of China

Preoperative pulmonary function assessment is applied to select surgical candidates and predict the occurrence of postoperative complications. This present study enrolled 2323 colorectal cancer patients. Forced vital capacity (FVC) and maximal voluntary ventilation (MVV) were measured as predicted values. Associations between patient pulmonary function and both prognosis and postoperative complications was analyzed. The value of FVC and MVV optimal cutoff was 98.1 (P < .001) and 92.5 (P < .001), respectively. Low FVC and low MVV were associated with higher rates of postoperative fever (23.8% vs 13.9%, P < .001; 17.8% vs 13.3%, P = .049, respectively) and with higher rates of pneumonia (3.75% vs 1.73%, P = .002; 3.00% vs 1.71%, P = .009, respectively), pleural effusion (3.00% vs 1.57%, P = .033; 3.18% vs 1.42%, P = .006, respectively), and poor patient prognosis (5-year overall survival: 80.0% vs 90.3%, P < .001; 71.7% vs 91.9%, P < .001, respectively). In addition, low FVC was closely related to the higher rate of anastomosis leak (4.31% vs 2.29%, P = .013), low MVV was correlated with the higher rate of uroschesis (2.38% vs 0.65%, P < .001). In subgroup analyses, the predictive value of FVC and MVV in patients with different tumor stage was analyzed. Both low FVC and MVV were independent risk factors for poor prognosis in stage II and III, indicating that low FVC and MVV are predictive of poorer prognosis and higher risk of postoperative complications in colorectal cancer patients.

Mismatch Repair Status Correlates with Survival in Young Adults with Metastatic Colorectal Cancer

BACKGROUND

Young adults with metastatic colorectal cancer (mCRC) may have higher rates of deficient mismatch repair (dMMR) than older patients. This study sought to assess patterns of MMR-testing and survival among young adult mCRC patients in the National Cancer Database (NCDB), hypothesizing that dMMR correlates with worse survival than in MMR-proficient (pMMR) patients.

METHODS

Stage-IV colorectal cancers were identified in NCDB (2010-2016). Demographic and clinical features were compared between younger (age ≤ 30) and older mCRC patients and tested for association with overall survival. Stage-IV disease without other recorded metastatic sites defined peritoneal metastasis (PM). Fisher-exact tests compared proportions and Cox models tested association with overall survival.

RESULTS

Of 124,587 stage-IV colorectal cancers, 1,123 (0.9%) were in young patients. Young patients were more likely to have mucinous histology, high-grade, rectal primaries, and isolated peritoneal metastases (P < 0.001). Younger patients more often had MMR-testing (29.1 versus 16.6%), with dMMR found at similar rates in young and older patients (21.7 versus 17.1% of those tested, P= 0.4). Despite higher rates of adverse prognostic features, younger patients had better survival (median 20.7 versus 14.8 months, P < 0.001). In MMR-tested patients, dMMR correlated with higher mortality risk compared to pMMR (median 16.6 months versus 25.5 months, P = 0.01). On multivariable analysis, grade and MMR-status remained independently associated with survival.

CONCLUSIONS

Median survival was worse with dMMR by 8.9 months compared to pMMR in young adults with mCRC. Despite higher rates of familial syndromes in young patients and recommendations for universal MMR-testing, over 70% of young mCRC patients had no MMR-status recorded.

Incidence and risk factors for preneoplastic and neoplastic lesions of the colon and rectum in patients under 50 referred for colonoscopy

Colorectal cancer (CRC) diagnosed before the age of 50, known as early-onset CRC (eoCRC), is considered uncommon. We aimed at analysing the incidence of preneoplastic and neoplastic lesions of the colon and rectum in patients under 50 years old and to identify possible predictors Methods: We retrospectively collected data from 1778 patients under 50 years old (mean age 39.9±7.8) referred for colonoscopy between 2015-2018. Cumulative incidence of adenomas and eoCRC was assessed. Multivariable regression models were fitted Results: The cumulative incidence for adenomas was 11.0% (95% CI 9-12), while it was 1.5% (95% CI 1-2) for eoCRC (metastatic disease in 13/27 patients). Age as a continuous variable was associated with the presence of adenomas (incidence rate ratio 1.06; 95% CI 1.03-1.09; p<0.001). EoCRC arose in most cases in the rectum (13/27, 48.1%). Age ≥40 was the main risk factor (OR 2.25; 95% CI 1.35-3.73; p=0.002) for both adenomas (160/196 patients, 81.6%) and eoCRC (20/27 patients, 74.1%), while smoking seemed to have no role (p=0.772). The presence of alarm symptoms was statistically significant at bivariable analysis for eoCRC only (OR 3.70; 95% CI 1.49-9.22; p=0.005), as well as having multiple gastrointestinal symptoms (OR 19.85; 95% CI 2.64-149.42; p=0.004). Only 3/27 (11.1%) patients with eoCRC had a family history for CRC Conclusions: A high cumulative incidence rate of both adenomas and eoCRC was found, this latter occurring more common in patients aged 40-49, without apparent risk factors. The presence of alarm symptoms or multiple gastrointestinal symptoms led to a late diagnosis.

Young-Onset Carcinogenesis - The Potential Impact of Perinatal and Early Life Metabolic Influences on the Epigenome

The last decade has witnessed a significant rise in cancers in young adults. This spectrum of solid organ cancers occurring in individuals under the age of 40 years (some reports extending the age-group to <50 years) in whom aetiology of cancer cannot be traced back to pre-existing familial cancer syndromes, is referred to as termed young-, or early- onset cancers. The underlying causes for young-onset carcinogenesis have remained speculative. We recently proposed a hypothesis to explain the causation of this entity. We propose that the risk for young-onset cancer begins in the perinatal period as a result of the exposure of the foetus to stressors, including maternal malnutrition, smoking or alcohol, with the consequent epigenomic events triggered to help the foetus cope/adapt. Exposure to the same stressors, early in the life of that individual, facilitates a re-activation of these 'responses designed to be protective' but ultimately resulting in a loss of regulation at a metabolic and/or genetic level culminating in the evolution of the neoplastic process. In this manuscript, we will provide a rationale for this hypothesis and present evidence to further support it by clarifying the pathways involved, including elucidating a role for Acetyl-CoA and its effect on the epigenome. We present strategies and experimental models that can be used to test the hypothesis. We believe that a concerted effort by experts in different, but complementary fields, such as epidemiology, genetics, and epigenetics united towards the common goal of deciphering the underlying cause for young-onset cancers is the urgent need. Such efforts might serve to prove, or disprove, the presented hypothesis. However, the more important aim is to develop strategies to reverse the disturbing trend of the rise in young-onset cancers.

Disparities in Early-Onset Colorectal Cancer

The incidence and mortality of early-onset colorectal cancer (CRC) are increasing in the United States (US) and worldwide. In the US, there are notable disparities in early-onset CRC burden by race/ethnicity and geography. African Americans, Hispanic/Latinos, and populations residing in specific regions of the Southern U.S. are disproportionately affected with CRC diagnosed at younger ages, while less is known about disparities in other countries. Reasons for these disparities are likely multi-factorial and potentially implicate differences in health determinants including biology/genetics, diet/environment, individual health behaviors, and access to high-quality health services, as well as social and policy factors. This review summarizes current understanding of early-onset CRC disparities and identifies specific research areas that will inform evidence-based interventions at individual, practice, and policy levels to reduce the global burden of this disease.

Colorectal Cancer among Resettlers from the Former Soviet Union and in the General German Population: Clinical and Pathological Characteristics and Trends

This study examined time trends and clinical and pathological characteristics of colorectal cancer (CRC) among ethnic German migrants from the Former Soviet Union (resettlers) and the general German population. Incidence data from two population-based cancer registries were used to analyze CRC as age-standardized rates (ASRs) over time. The respective general populations and resettler cohorts were used to calculate standardized incidence ratios (SIRs) by time-period (before and after the introduction of screening colonoscopy in 2002), tumor location, histologic type, grade, and stage at diagnosis. Additionally, SIRs were modeled with Poisson regression to depict time trends. During the study period from 1990 to 2013, the general populations showed a yearly increase of ASR, but for age above 55, truncated ASR started to decline after 2002. Among resettlers, 229 CRC cases were observed, resulting in a lowered incidence for all clinical and pathological characteristics compared to the general population (overall SIR: 0.78, 95% CI 0.68–0.89). Regression analysis revealed an increasing SIR trend after 2002. Population-wide CRC incidence decreases after the introduction of screening colonoscopy. In contrast the lowered CRC incidence among resettlers is attenuating to the general population after 2002, suggesting that resettlers do not benefit equally from screening colonoscopy.

Prospective evaluation of dietary and lifestyle pattern indices with risk of colorectal cancer in a cohort of younger women

BACKGROUND

Although colorectal cancer (CRC) incidence in the USA is declining overall, its incidence is increasing among those younger than 50 years of age. The reasons underlying the increasing trend are largely unknown, although behavioral changes, such as unhealthy diet and lifestyle factors, may be partially responsible.

DESIGN

A prospective cohort study included 94 217 women aged 26-45 years at baseline. Validated anthropometric measures and lifestyle information were self-reported biennially. Exposures were four recommendation-based dietary indices-the prime diet quality score and three plant-based dietary indices; and two mechanism-based indices-the empirical dietary and lifestyle index for hyperinsulinemia (EDIH and ELIH). We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) for overall CRC and for early-onset (before age 50) and after age 50 CRC separately.

RESULTS

We documented 332 cases of CRC during 24 years of follow-up (2 113 655 person-years), with an average age of 52 ± 7 years at diagnosis. Hyperinsulinemic dietary and lifestyle patterns were associated with a higher risk of CRC. Multivariable-adjusted HRs (95% CIs) comparing participants in the highest versus lowest quartile were: 1.67 for EDIH (95% CI: 1.15-2.44, P-trend = 0.01) and 1.51 for ELIH (95% CI: 1.10-2.08, P-trend = 0.01). Moreover, per 75% increment in rank, ELIH appeared to be a stronger risk factor for early-onset CRC (HR = 1.86, 95% CI: 1.12-3.07) than after age 50 CRC (HR = 1.20, 95% CI: 0.83-1.73, P-heterogeneity = 0.16). The four recommendation-based indices were not significantly associated with overall, early-onset, or after age 50 CRC risk (per 75% increment in rank, HRs ranged from 0.75 to 1.28).

CONCLUSION

Dietary and lifestyle patterns contributing to hyperinsulinemia were associated with greater CRC risk in younger women. Moreover, the hyperinsulinemic lifestyle showed a suggestively stronger positive association with early-onset CRC risk, compared with after age 50 CRC. Our findings suggest that dietary and lifestyle interventions to reduce insulinemic potential may be effective for CRC prevention among younger women.

Comprehensive Genomic Characterization of Fifteen Early-Onset Lynch-Like Syndrome Colorectal Cancers

Simple Summary

The most prevalent type of hereditary colorectal cancer is called Lynch syndrome and it is characterized by a tumor phenotype called microsatellite instability (MSI). This disease is a consequence of germline (inheritable) variants in any of the four mismatch repair (MMR) DNA genes, being their identification essential to ensure their appropriate diagnosis and implementation of preventive measurements. Nevertheless, only 50% of patients with MSI and suspected Lynch syndrome actually carry a germline pathogenic variant in an MMR gene that explains the clinical entity. The remaining 50% are termed Lynch-like syndrome, and their causes remain unknown. In this work, we tried to elucidate the molecular mechanisms that underlie this rare entity in a group of early-onset Lynch-like syndrome colorectal cancer, through whole-exome sequencing of germline and tumor samples. We observed that one-third of these patients have somatic alterations in genes associated with the MMR system and that these could be the mechanism causing their unexplained MSI. Furthermore, we found that patients who showed biallelic somatic alterations also carried germline variants in new candidate genes associated with DNA repair functions and that this could be, partly, the cause of the early onset in this cohort.

Abstract

Lynch-like syndrome (LLS) is an increasingly common clinical challenge with an underlying molecular basis mostly unknown. To shed light onto it, we focused on a very young LLS early-onset colorectal cancer (CRC) cohort (diagnosis ≤ 40 y.o.), performing germline and tumor whole-exome sequencing (WES) of 15 patients, and additionally analyzing their corresponding tumor mutational burden (TMB) and mutational signatures. We identified four cases (27%) with double somatic putative variants in mismatch repair (MMR) core genes, as well as three additional cases (20%) with double MSH3 somatic alterations in tumors with unexplained MSH2/MSH6 loss of expression, and two cases (13%) with POLD1 potential biallelic alterations. Average TMB was significantly higher for LLS cases with double somatic alterations. Lastly, nine predicted deleterious variants in genes involved in the DNA repair functions and/or previously associated with CRC were found in nine probands, four of which also showed MMR biallelic somatic inactivation. In conclusion, we contribute new insights into LLS CRC, postulating MSH3 and POLD1 double somatic alterations as an underlying cause of a microsatellite instability (MSI) phenotype, proposing intrinsic biological differences between LLS with and without somatic alterations, and suggesting new predisposing candidate genes in this scenario.

Young-onset colorectal cancer is associated with a personal history of type 2 diabetes

BACKGROUND

Colorectal cancer (CRC) is rising in incidence in young adults, and this observation is currently unexplained. We investigated whether having a personal history of type 2 diabetes mellitus (T2D) was a potential risk factor for young-onset colorectal cancer (YOCRC).

METHODS

The South Australian Young Onset (SAYO) CRC study is a series of young adults with CRC below age 55. Ninety unrelated YOCRC cases were recruited to the study. Personal history and detailed family history of T2D were obtained at face-to-face interview and confirmed from medical records. Whole exome sequencing was conducted on germline DNA from each CRC case. Controls for personal history studies of T2D were 240 patients with proven clear colonoscopies and no known CRC predispositions.

RESULTS

The median age of YOCRC cases was 44 years (18-54) and of controls was 45 years (18-54), and 53% of both cases and controls were females (P = 0.99). Left-sided (distal) CRC was seen in 67/89 (75%) of cases. A personal history of T2D was confirmed in 17/90 (19%) YOCRC patients compared with controls (12/240, 5%; P < 0.001; odds ratio = 4.4; 95% confidence interval, 2.0-9.7). YOCRC patients frequently reported at least one first-degree relative with T2D (32/85, 38%). Ten of 87 (12%) of YOCRC cases had CRC-related pathogenic germline variants, however, no pathogenic variants in familial diabetes-associated genes were seen.

CONCLUSIONS

Though the mechanism remains unclear, our observations suggest that there is enrichment for personal history of T2D in YOCRC patients.

IMPACT

A diagnosis of T2D could therefore potentially identify a subset of young adults at increased risk for CRC and in whom early screening might be appropriate.