Early-onset colorectal cancer (EOCRC) shows a different epidemiological trend compared to later-onset colorectal cancer, with its incidence rising in most regions and countries worldwide. However, the reasons behind this trend remain unclear. The etiology of EOCRC is complex and could involve both genetic and environmental factors. Apart from Lynch syndrome and Familial Adenomatous Polyposis, sporadic EOCRC exhibits a broad spectrum of pathogenic germline mutations, genetic polymorphisms, methylation changes, and chromosomal instability. Early-life exposures and environmental risk factors, including lifestyle and dietary risk factors, have been found to be associated with EOCRC risk. Meanwhile, specific chronic diseases, such as inflammatory bowel disease, diabetes, and metabolic syndrome, have been associated with EOCRC. Interactions between genetic and environmental risk factors in EOCRC have also been explored. Here we present findings from a narrative review of epidemiological studies on the assessment of early-life exposures, of EOCRC-specific environmental factors, and their interactions with susceptible loci. We also present results from EOCRC-specific genome-wide association studies that could be used to perform Mendelian randomization analyses to ascertain potential causal links between environmental factors and EOCRC.

The aim of the study was to evaluate the association of frequency of polyp diagnosis in relatives with the risk of overall and early-onset colorectal cancer (CRC).

Data from nationwide Swedish family cancer datasets (1964-2018) were leveraged to calculate standardized incidence ratios for individuals with a family history of polyp by frequency of polyp diagnosis in family members.

A total of 11,676,043 individuals were followed for up to 54 years. Compared with the risk in individuals without a family history of colorectal tumor (n = 142,234), the risk of overall CRC was 1.4-fold in those with 1 first-degree relative (FDR) with 1-time polyp diagnosis (95% CI, 1.3-1.4; n = 11,035; early-onset standardized incidence ratio [SIR], 1.4; 95% CI, 1.3-1.5; n = 742). The risk was significantly higher in individuals with 1 FDR with 2 or more (frequent) polyp diagnoses (overall CRC: SIR, 1.8; 95% CI, 1.8-1.9; early-onset CRC: SIR, 2.3; 95% CI, 2.0-2.6). A rather similar risk was observed for individuals with ≥2 FDRs with 1-time polyp diagnosis (overall CRC: SIR, 1.9; 95% CI, 1.7-2.1; early-onset CRC: SIR, 2.2; 95% CI, 1.5-2.9). Individuals with ≥2 FDRs with frequent polyp diagnoses had a 2.4-fold overall risk (95% CI, 2.2-2.7) and a 3.9-fold early-onset risk (95% CI, 2.8-5.3). Younger age at polyp diagnosis in FDRs was associated with an increased risk of CRC. A family history of polyp in second-degree relatives was important only when there were frequent diagnoses of polyp.

A higher frequency of colorectal polyp diagnosis in relatives is associated with a greater risk of CRC, especially early-onset CRC. This risk is independent of number of affected relatives or youngest age at polyp diagnosis. These findings underscore the need for more personalized CRC screening strategies that are tailored to individuals with a family history of polyp.

The incidence of gastrointestinal stromal tumors (GISTs) has risen, but early-onset GISTs (age <50 years) remain underexplored. This study aims to compare the clinical characteristics and prognostic outcomes of early-onset GISTs with later-onset cases (age ≥50 years).

We conducted a retrospective study using data on GISTs diagnosed from 2000 to 2021 in the Surveillance, Epidemiology, and End Results (SEER) database. Prognostic factors for overall survival (OS) and cancer-specific survival (CSS) were analyzed using Cox regression and competing risk analysis. Kaplan-Meier and cumulative risk curves assessed survival disparities, and forest plots were used for subgroup analyses. Bias was minimized through multiple imputation, propensity score matching (PSM), and stratified regression.

Among 12,608 GIST cases, 2,271 (18%) were early-onset, and 10,337 (82%) were later-onset. Median age and survival for early-onset cases were 43 years and 70 months, respectively, vs. 66 years and 48 months for later-onset cases. Early-onset patients had larger tumor diameters, higher liver metastasis rates, higher mitotic rates, and higher risk stratification at diagnosis. They also underwent surgery more frequently than later-onset patients. Cox and competing risk analyses indicated a survival advantage for early-onset patients. Kaplan-Meier and cumulative risk curves confirmed better OS and CSS for early-onset patients before and after matching (P<0.001). This advantage persisted across stages, risk strata, and subgroups.

Early-onset GISTs have distinct clinicopathological features and better OS and CSS compared to later-onset patients.

The incidence of early-onset colorectal cancer (EOCRC) (< 50 years) has been steadily rising, with a parallel increase in metastatic and invasive cases. To elucidate the molecular mechanisms underlying this aggressive phenotype, we performed comprehensive multi-omics profiling to delineate the distinct features of EOCRC, with a focus on key drivers of metastatic and invasive potential.

We initially characterized the genome, epigenome, and transcriptome of tumors from 515 (69 EOCRC and 446 late-onset CRC [LOCRC]) cases in The Cancer Genome Atlas. Key candidate molecules were further validated using RNA-seq and scRNA-seq data. Multi-omics profiling revealed PIWIL1/piRNA as a hallmark of EOCRC, with further validation through in vitro functional assays, transcriptomic profiling, and Kaplan-Meier survival analysis.

EOCRC demonstrated a mutational landscape similar to that of LOCRC, with comparable oncogenic driver mutations and somatic copy-number alterations. However, EOCRC exhibited a higher frequency of deletion in chromosomes 6, 15, and 19 regions, along with metabolic reprogramming favoring aerobic glycolysis and lipid metabolism. Integrative transcriptomic and DNA methylation analyses identified six EOCRC-specific molecules, including PIWIL1. Notably, PIWIL1 was mainly expressed in epithelial cells, with lower expression in EOCRC versus LOCRC. Its downstream piRNAs (FR019019, FR019089, and FR132045) were also downregulated in EOCRC. Functional experiments demonstrated that FR019089/FR019019 overexpression suppressed migration and invasion. Clinically, low FR019089 levels correlated with significantly shorter progression-free and overall survival in EOCRC patients. Additionally, downstream pathways of FR019089 and FR019019 overexpression were enriched in anti-cancer-related signaling pathways.

Our multi-omics approach yields novel insights into the molecular underpinnings of EOCRC and we characterize the role of PIWIL1-associated piRNAs in modulating EOCRC metastasis and invasion. FR019089 shows promise as a prognostic biomarker with potential clinical utility in the risk stratification and management of EOCRC patients.

Palliative rectal cancer patients typically retain their primary tumour, as trials have concluded no survival benefit of tumour resection in non-curative patients. This patient group is understudied regarding the natural course of the remaining tumour, particularly concerning the need of surgical management.

This was a retrospective study on rectal cancer patients diagnosed between 2007 and 2020 in Region Västerbotten, Sweden. Data were obtained from the Swedish Colorectal Cancer Registry and chart review. Patients were excluded if treated with curative intent, underwent primary tumour resection, had a synchronous colorectal cancer, had locally recurrent colorectal cancer, or refused treatment. Patients were followed from diagnosis until death or end of follow-up. Indications for palliative treatment, tumour-related complications and surgical and oncological management were investigated, with a stratified analysis for study period and patient age.

Some 156 patients remained after applying exclusion criteria. The majority had metastasized and incurable disease (76%). Almost half suffered local complications (44%) and 48% underwent surgical intervention, due to the unremoved primary tumour. Tumour perforation occurred in 7% with a significantly higher risk in patients aged ≤75 years (p = 0.009). Bowel obstruction afflicted 23%, while 40% underwent stoma diversion. Almost half received chemotherapy (48%) and radiotherapy (42%), respectively.

Rectal cancer patients with an unremoved primary tumour face a substantial risk of local complications, often necessitating surgical intervention. Therefore, the benefits of surgical resection should be carefully considered, especially for patients with a longer estimated survival. Further research is needed to accurately identify patients where tumour removal might be beneficial.

Few studies have systematically compared the overlap and complementarity of family history (FH) and polygenic risk score (PRS) in terms of disease risk. We here investigated the impacts of FH and PRS on the risk of incident diseases or age at disease onset, as well as their clinical value in risk prediction. We analyzed 12 diseases in the prospective cohort study of UK Biobank (N = 461,220). First, restricted mean survival time analysis was performed to evaluate the influences of FH and PRS on age at onset. Then, Cox proportional hazards model was employed to estimate the effects of FH and PRS on the incident risk. Finally, prediction models were constructed to examine the clinical value of FH and PRS in the incident disease risk. Compared to negative FH, positive FH led to an earlier onset, with an average of 2.29 years earlier between the top and bottom 2.5% PRSs and high blood pressure showing the greatest difference of 6.01 years earlier. Both FH and PRS were related to higher incident risk; but they only exhibited weak interactions on high blood pressure and Alzheimer's disease/dementia, and provided relatively independent and partially complementary information on disease susceptibility, with PRS explaining 7.0% of the FH effect but FH accounting for only 1.1% of the PRS effect for incident cases. Further, FH and PRS showed additional predictive value in risk evaluation, with breast cancer showing the greatest improvement (31.3%). FH and PRS significantly affect a variety of diseases, and they are not interchangeable measures of genetic susceptibility, but instead offer largely independent and partially complementary information. Incorporating FH, PRS, and clinical risk factors simultaneously leads to the greatest predictive value for disease risk assessment.

The polygenic risk score (PRS) has been perceived as advantageous in predicting the risk of complex diseases compared to other measures. We aimed to systematically evaluate the influence of PRS on disease outcome and to explore its predictive value.

We comprehensively assessed the relationship between PRS and 32 complex diseases in the UK Biobank. We used Cox models to estimate the effects of PRS on the incidence risk. Then, we constructed prediction models to assess the clinical utility of PRS in risk prediction. For 16 diseases, we further compared the disease risk and prediction capability of PRS across early and late-onset cases.

Higher PRS led to greater incident risk, with hazard ratio (HR) ranging from 1.07 (95% confidence interval (CI) = 1.06-1.08) for panic/anxiety disorder to 4.17 (95% CI = 4.03-4.31) for acute pancreatitis. This effect was more pronounced in early-onset cases for 12 diseases, increasing by 52.8% on average. Particularly, the early-onset risk of heart failure associated with PRS (HR = 3.02; 95% CI = 2.53-3.59) was roughly twice compared to the late-onset risk (HR = 1.48; 95% CI = 1.46-1.51). Compared to average PRS (20-80%), individuals positioned within the top 2.5% of the PRS distribution exhibited varying degrees of elevated risk, corresponding to a more than five times greater risk on average. PRS showed additional value in clinical risk prediction, causing an average improvement of 6.1% in prediction accuracy. Further, PRS demonstrated higher predictive accuracy for early-onset cases of 11 diseases, with heart failure displaying the most significant (37.5%) improvement when incorporating PRS into the prediction model (concordance index (C-index) = 0.546; standard error (SE) = 0.011 vs. C-index = 0.751; SE = 0.010, P = 2.47 × 10-12).

As a valuable complement to traditional clinical risk tools, PRS is closely related to disease risk and can further enhance prediction accuracy, especially for early-onset cases, underscoring its potential role in targeted prevention for high-risk groups.

Polygenic risk scores (PRS) hold prognostic value for identifying individuals at higher risk of type 2 diabetes (T2D). However, further characterization is needed to understand the generalizability of T2D PRS in diverse populations across various contexts. We characterized a multi-ancestry T2D PRS among 244,637 cases and 637,891 controls across eight populations from the Population Architecture Genomics and Epidemiology (PAGE) Study and 13 additional biobanks and cohorts. PRS performance was context dependent, with better performance in those who were younger, male, with a family history of T2D, without hypertension, and not obese or overweight. Additionally, the PRS was associated with various diabetes-related cardiometabolic traits and T2D complications, suggesting its utility for stratifying risk of complications and identifying shared genetic architecture between T2D and other diseases. These findings highlight the need to account for context when evaluating PRS as a tool for T2D risk prognostication and potentially generalizable associations of T2D PRS with diabetes-related traits despite differential performance in T2D prediction across diverse populations.

Both genetic factors and lifestyle play a critical role in colorectal cancer, but the extent to which an increased genetic risk can be offset by a healthy lifestyle remains unclear.

We included 51,171 participants from the Prostate, Lung, Colorectal, and Ovarian Cancer cohort. A polygenic risk score was created based on 205 genetic variants associated with colorectal cancer, and a healthy lifestyle score was constructed based on six lifestyle factors. Cox regression models were used to evaluate the association of genetic and lifestyle factors with colorectal cancer incidence.

Compared with individuals at low genetic risk (the lowest 20%), those with intermediate genetic risk (20%-80%) and high genetic risk (the highest 20%) had a significantly increased risk of colorectal cancer (HR = 1.71 and 2.52, respectively). Compared with participants with a favorable lifestyle (scoring 4-6), those with an unfavorable lifestyle (scoring 0 or 1) had a 47% higher risk of colorectal cancer. Moreover, participants with a high genetic risk and a favorable lifestyle had a 45% lower risk of colorectal cancer than those with a high genetic risk and an unfavorable lifestyle, with their 10-year absolute risks of 1.29% and 2.07%, respectively.

Our findings suggest that adherence to a healthy lifestyle holds promise to reduce the genetic impact on colorectal cancer risk.

This study indicates that modifiable lifestyle factors play an important role in colorectal cancer prevention, providing new insights for personalized prevention strategies.

Many patients with colorectal polyposis demonstrate negative results in germline mutation test. This study aimed to uncover genetic variants associated with nonhereditary colorectal polyposis using a genome-wide association study (GWAS).

At a single referral university hospital, between January 2012 and September 2021, 638 patients with ≥ 10 biopsy-proven cumulative polyps on colonoscopy without germline mutations related to hereditary colorectal cancer or polyposis were included. The control group comprised 1863 individuals from the Korea Medical Institute, each having undergone at least two colonoscopies, all of which were normal. This study utilized GWAS to identify susceptibility loci for nonhereditary colorectal polyposis. Genetic differences between patients with and without ≥ 10 polyp recurrences were analyzed using Cox proportional hazards models.

GWAS revealed 71 novel risk single-nucleotide polymorphisms (SNPs) not seen in previous colorectal cancer and polyp GWAS. Five genes (UPF3A, BICRA, CBWD6, PDE4DIP, and ABCC4) overlapping seven SNPs (rs566295755, rs2770288, rs1012003, rs201270202, rs71264659, rs1699813, and rs149368557), previously linked to colorectal cancer, were identified as significant risk factors for nonhereditary colorectal polyposis. Two novel genes (CNTN4 and CNTNAP3B), not previously associated with colorectal diseases, were identified. Three SNPs (rs149368557, rs12438834, and rs9707935) were significantly associated with higher risk of recurrence of polyposis. The gene overlapping with rs149368557 was ABCC4, which was also significantly associated with an increased risk of nonhereditary colorectal polyposis.

This study identified 71 novel risk variants for nonhereditary colorectal polyposis, with three SNPs (rs149368557, rs12438834, and rs9707935) indicating significant associations with increased risk of polyposis recurrence.

Genomic screening to identify individuals with Lynch Syndrome (LS) and those with a high polygenic risk score (PRS) promises to personalize colorectal cancer (CRC) screening. Understanding its clinical and economic impact is needed to inform screening guidelines and reimbursement policies.

We developed a Markov model to simulate individuals over a lifetime. We compared LS+PRS genomic screening with standard of care (SOC) for a cohort of US adults at age 30. The Markov model included health states of no CRC, CRC stages (A-D), and death. We estimated incidence, mortality, and discounted economic outcomes of the population under different interventions.

Screening 1000 individuals for LS+PRS resulted in 1.36 fewer CRC cases and 0.65 fewer deaths compared with SOC. The incremental cost-effectiveness ratio was $124,415 per quality-adjusted life year; screening had a 69% probability of being cost-effective using a willingness-to-pay threshold of $150,000/quality-adjusted life year . Setting the PRS threshold at the 90th percentile of the LS+PRS screening program to define individuals at high risk was most likely to be cost-effective compared with 95th, 85th, and 80th percentiles.

Population-level LS+PRS screening is marginally cost-effective, and a threshold of 90th percentile is more likely to be cost-effective than other thresholds.

Colorectal cancer (CRC) incidence and mortality before 50 have been rising alarmingly in the recent decades.

Using a cohort of 10,000 patients, this study investigates the clinical, mutational, and co-mutational features of CRC in early-onset (EOCRC, < 50 years) compared to late-onset (LOCRC, ≥ 50 years).

EOCRC was associated with a higher prevalence of Asian and Hispanic patients, rectal or left-sided tumors (72% vs. 59%), and advanced-stage disease. Molecular analyses revealed differences in mutation patterns, with EOCRC having higher frequencies of TP53 (74% vs. 68%, p < 0.01) and SMAD4 (17% vs. 14%, p = 0.015), while BRAF (5% vs. 11%, p < 0.001) and NOTCH1 (2.7% vs. 4.1%, p = 0.01) mutations were more prevalent in LOCRC. Stratification by tumor site and MSI status highlighted significant location- and age-specific molecular differences, such as increased KRAS and CTNNB1 mutations in right-sided EOCRC and higher BRAF prevalence in MSI-H LOCRC (47% vs. 6.7%, p < 0.001). Additionally, co-occurrence analysis revealed unique mutational networks in EOCRC MSS, including significant co-occurrences of FBXW7 with NOTCH3, RB1, and PIK3R1.

This study highlights the significance of age-specific molecular profiling, offering insights into the unique biology of EOCRC and potential clinical applications.

Since the early 1990s, there has been a dramatic rise in gastrointestinal cancers diagnosed in patients under age 50 for reasons that remain poorly understood. The most significant change has been the increase in incidence rates of early-onset colorectal cancer, especially rates of left-sided colon and rectal cancers. Increases in gastric, pancreatic, and other gastrointestinal cancer diagnoses have further contributed to this trend. We formed a multidisciplinary Think Tank to develop a strategic, coordinated approach to studying early-onset gastrointestinal cancers. This area of research is challenging given multifactorial etiologies. We focused on epidemiology and the environment, the microbiome, and survivorship as key pillars to structure a research framework. We advocate a comprehensive strategy to (1) use existing biospecimens, especially those collected longitudinally, with correlation to exposures (the exposome); (2) standardize microbiome specimen collection and analyses of blood, tissue, and stool specimens to minimize contamination and biases; (3) prioritize mechanistic studies to evaluate findings from biomarker studies; and (4) explore the unique survivorship needs of this young population. These recommendations build upon prior efforts with the goal of streamlining research into this important field of study while minimizing redundant efforts. We hope that our findings serve as a clarion call to motivate others to discover why young individuals are being diagnosed with gastrointestinal cancers at such an alarming rate and how to best support those who have been diagnosed.

Early-onset cancer (diagnosed under age 50) generally manifests as an aggressive disease phenotype. The association between healthy lifestyle and early-onset cancer and whether it varies by common genetic variants remains unclear.

We analyzed a prospective cohort of 66 308 participants who were under age 50 and free of cancer at baseline in the UK Biobank. Using Cox regression, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for early-onset total and breast cancer based on sex-specific composite total cancer polygenic risk scores (PRSs), a breast cancer-specific PRS, and sex-specific health-associated lifestyle scores (HLSs).

In multivariable-adjusted analyses with 2-year latency, higher genetic risk (highest vs lowest tertile of PRS) was associated with significantly increased risks of early-onset total cancer in females (HR, 95% CI = 1.83, 1.49 to 2.26) and males (2.03, 1.51 to 2.73) as well as early-onset breast cancer in females (3.06, 2.20 to 4.26). An unfavorable lifestyle (highest vs lowest category of HLS) was associated with higher risk of total cancer and breast cancer in females across genetic risk categories; the association with total cancer and breast cancer was stronger in the highest genetic risk category than the lowest: HRs (95% CIs) were 1.55 (1.12 to 2.14) and 1.69 (1.11 to 2.57) in the highest genetic risk category and 1.03 (0.64 to 1.67) and 0.81 (0.36 to 1.85) in the lowest.

Genetic and lifestyle factors were independently associated with early-onset total and breast cancer risk. Individuals with a high genetic risk may benefit more from adopting a healthy lifestyle in preventing early-onset cancer.

Colorectal cancer (CRC) is a complex disease with monogenic, polygenic and environmental risk factors. Polygenic risk scores (PRSs) aim to identify high polygenic risk individuals. Due to differences in genetic background, PRS distributions vary by ancestry, necessitating standardization. We compared four post-hoc methods using the All of Us Research Program Whole Genome Sequence data for a transancestry CRC PRS. We contrasted results from linear models trained on A. the entire data or an ancestrally diverse subset AND B. covariates including principal components of ancestry or admixture. Standardization with the training subset also adjusted the variance. All methods performed similarly within ancestry, OR (95% C.I.) per s.d. change in PRS: African 1.5 (1.02, 2.08), Admixed American 2.2 (1.27, 3.85), European 1.6 (1.43, 1.89), and Middle Eastern 1.1 (0.71, 1.63). Using admixture and an ancestrally diverse training set provided distributions closest to standard Normal. Training a model on ancestrally diverse participants, adjusting both the mean and variance using admixture as covariates, created standard Normal z-scores, which can be used to identify patients at high polygenic risk. These scores can be incorporated into comprehensive risk calculation including other known risk factors, allowing for more precise risk estimates.

Cancer remains a major global health burden, with incidence rates rising globally. The Arab world, which is often regarded as an underrepresented population in literature, shows distinct patterns in cancer incidences, genetics, and outcomes in comparison with Western populations. This review aims to highlight key genomic studies conducted in the Arab world. We describe the epidemiological and genetic landscape of cancer in the Arab populations, focusing on lung, breast, and colorectal cancers, given their prominence and distinctive patterns in the region. We utilised data from GLOBOCAN 2022 and published genomic studies to assess subregional incidence trends, identify significant mutations, and explore hereditary and early-onset cancers profiles. Breast, lung, and colorectal cancers dominate the cancer profile in the region, with disparities in genetic alterations when compared to global trends. Variation in EGFR mutation frequencies in lung cancer across diverse ethnicities in the MENA region is representative of the extreme heterogeneity in the Arab region. Variations in BRCA1/2 mutation frequency, and unique founder mutations highlight breast cancer's particular regional genetic traits. Similarly, colorectal cancer studies show variations in mutational profiles, such as a low incidence of BRAF mutations and distinct epigenetic characteristics that represent region-specific disease pathways. Early-onset cancers, particularly breast and colorectal cancers, occur at higher rates than in Western populations and often diverge from the typical germline mutation patterns reported globally. The review emphasises the importance of conducting localised genetic studies in improving personalised medicine and public health strategies. Despite these efforts, significant gaps remain, particularly in understanding early-onset cancers and hereditary cancer genetic disorders, which are overrepresented in the region. Further research on the genetic basis of cancer in Arab populations is essential for advancing personalised treatment and improving cancer outcomes in these under-researched groups.

We aimed to investigate the interrelationships among polygenic risk scores (PRS), healthy lifestyle factors (HLFs), and colorectal cancer (CRC) risk in individuals with prediabetes. To investigate whether adherence to HLFs influence CRC risk in those with elevated PRS within this specific population.

Data from 22,408 prediabetes participants without CRC at baseline were analyzed from the UK Biobank. HLFs were graded using healthy lifestyle scores (HLSs) and classified as favorable, intermediate, or unfavorable, while the PRS for CRC was categorized as high, medium, or low. Cox proportional hazards models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI) for CRC risk.

High PRS (HR: 2.36; 95% CI: 1.86-3.00) and medium PRS (HR: 1.42; 95% CI: 1.09-1.83) prediabetes were associated with increased CRC risk compared to those with low PRS. HLFs were linked to lower CRC risk in a dose-response manner, with never smoking (HR: 0.69; 95% CI: 0.57-0.84) and maintaining a healthy BMI (HR: 0.64; 95% CI: 0.49-0.82) associated with reduced CRC risk. Adherence to favorable HLFs may reduce the CRC risk in those with medium (HR: 0.51; 95% CI: 0.27-0.95) and high PRS (HR: 0.62; 95% CI: 0.39-0.99) over 15 years of follow-up. In participants with high PRS and unfavorable HLFs, the excess risk due to the additive interaction between PRS and HLFs was 1.41% (p < 0.01), especially for women (1.07%).

There is an additive interaction of PRS and HLFs on CRC risk in individuals with prediabetes. Adopting favorable HLFs should be integrated into the management of prediabetes individuals to reduce the risk of CRC.

A polygenic risk score (PRS) combines the associations of multiple genetic variants that could be due to direct causal effects, indirect genetic effects, or other sources of familial confounding. We have developed new approaches to assess evidence for and against causation by using family data for pairs of relatives (Inference about Causation from Examination of FAmiliaL CONfounding [ICE FALCON]) or measures of family history (Inference about Causation from Examining Changes in Regression coefficients and Innovative STatistical AnaLyses [ICE CRISTAL]). Inference is made from the changes in regression coefficients of relatives' PRSs or PRS and family history before and after adjusting for each other. We applied these approaches to two breast cancer PRSs and multiple studies and found that (a) for breast cancer diagnosed at a young age, for example, <50 years, there was no evidence that the PRSs were causal, while (b) for breast cancer diagnosed at later ages, there was consistent evidence for causation explaining increasing amounts of the PRS-disease association. The genetic variants in the PRS might be in linkage disequilibrium with truly causal variants and not causal themselves. These PRSs cause minimal heritability of breast cancer at younger ages. There is also evidence for nongenetic factors shared by first-degree relatives that explain breast cancer familial aggregation. Familial associations are not necessarily due to genes, and genetic associations are not necessarily causal.

Colorectal cancer (CRC) is a common cancer in Ireland. Of all CRCs, 2-4% are attributable to Lynch Syndrome (LS), the most common CRC predisposition syndrome. LS is caused by constitutional pathogenic variants (PVs) affecting mismatch repair (MMR) genes with resultant MMR protein deficiency (dMMR). Screening of all CRCs with MMR immunohistochemistry (IHC) testing is advocated to increase the detection of LS. However, successful implementation requires appropriate downstream management. In Ireland the traditional pathway involves referral to cancer genetics services to assess eligibility for genetic testing. Cancer genetics services in Ireland face many challenges in providing uniform access to timely healthcare with current wait times for assessment in excess of 1 year. An increasingly adopted pathway is that of mainstreaming, whereby genetic testing is managed locally by a multidisciplinary team member. Our institution therefore implemented an Advanced Nurse Practitioner (ANP)-led service with responsibility for the LS Diagnostic Pathway and mainstream genetic testing. Data was extracted from a prospectively maintained database of all newly diagnosed CRC patients discussed at our institutions CRC multidisciplinary meeting (MDM) between January 1st, 2023, and May 31st, 2024. MMR IHC testing was performed in 97.9% of the 385 patients diagnosed with CRC. The median time from histological confirmation of CRC to the availability of the MMR IHC report was 6 days. All 51 patients (100%) who required sequential tumor testing underwent BRAF V600 ± MLH1 promoter methylation testing. Additionally, 100% of the 14 patients eligible for mainstream genetic testing were referred to the ANP-led genetics service. The median time from the initial MDM discussion to the initiation of genetic testing was 69 days, while the median time from testing to the availability of results was 19 days. Patients received their results within a median of 21 days. MMR IHC testing increases the detection of LS through identification of dMMR tumours. Successful downstream delivery of clinical services, however, requires appropriate subsequent management, in a resource-limited environment. Our institutional experience demonstrates the feasibility, efficiency, and effectiveness of an ANP-led mainstreaming model of care for hereditary colorectal cancer.

We aimed to study the risk factors of early-onset colorectal cancer (CRC) incidence in the Iranian population. Early onset CRC in Iran is a relevant health issue that deserves further epidemiological efforts to be defined and controlled as far as possible. Early age screening of low-tract of the intestine would be particularly useful in families of colorectal cancer patients.

We analyzed data from a multicenter hospital-based case-control study in Iran (The Iranian Study of Opium and Cancer). Sociodemographic and lifestyle information was collected using validated questionnaires. Multivariate logistic regressions estimated the odds ratios (OR) and 95% confidence intervals (CIs) for the association of early-onset CRC in individuals under the age of 50 and potential risk factors, including physical activity, socioeconomic status, body shape at age 15, dietary factors, vitamin D, cigarettes and waterpipe smoking, opium use and family history of CRC. Additionally, a subgroup analysis was conducted for individuals with a very young age of CRC onset (i.e. <35 years).

We analyzed data of 189 developed CRC below age 50 (99 colon and 90 rectum), and 66 patients under the age 35 (13 colon and 21 rectum). Early CRC was inversely associated with vegetables (OR, 0.59; 95% CI, 0.38-0.92 for 422-576 g/day) and vitamin D (OR, 0.49; 95% CI, 0.26-0.94), and positively associated with red meat intake (OR, 1.80; 1.15-2.83 per 25.65 g/day). Vegetables (OR, 0.51; 95% CI, 0.27-0.98 for 576 g/day), red meat (OR, 2.05; 95% CI, 1.11-3.79 for 25.65 g/day), vitamin D (OR, 0.29; 95% CI, 0.10-0.86) and opium use (OR, 2.61; 95% CI, 1.01-6.74) were associated with early rectum cancer. Results were heterogeneous by cancer site for high fruit and vegetables intakes and cigarette smoking. Family history was associated with CRC (OR, 3.16; 95% CI, 1.29-10.9) and rectum cancer (OR, 3.22; 95% CI, 1.24-14.4) in subjects younger than 35, and, to a lesser extent, with CRC and rectum cancer before age 50.

Early-onset CRC was related to the intake of vegetables, vitamin D and red meat in Iran. Early-onset rectum cancer was associated with regular opium use. Family history was associated with early CRC and early rectum cancer, particularly below the age of 35.

Risk prediction and disease prevention are the innovative care challenges of the 21st century. Apart from freeing the individual from the pain of disease, it will lead to low medical costs for society. Until very recently, risk assessments have ushered in a new era with the emergence of omics technologies, including genomics, transcriptomics, epigenomics, proteomics, and so on, which potentially advance the ability of biomarkers to aid prediction models. While risk prediction has achieved great success, there are still some challenges and limitations. We reviewed the general process of omics-based disease risk model construction and the applications in four typical diseases. Meanwhile, we highlighted the problems in current studies and explored the potential opportunities and challenges for future clinical practice.

We aimed to identify predictors of and heterogeneity in survival among different age groups of patients with early-onset colorectal cancer (EOCRC).

This retrospective cohort study used National Cancer Database data from 2004 to 2019. Differences in survival among CRC patients <50 years, subcategorized into age groups (<20, 20-29, 30-39, 40-49 years) were compared for demographic, clinical, and histologic features by univariate and multivariate analyses. Cox hazard regression and Kaplan Meier survival analysis were performed.

134 219 of the 1 240 787 individuals with CRC (10.8%) were <50 years old; 46 639 (34.8%) had rectal and 87 580 (65.3%) had colon cancer. Within the colon cancer cohort, individuals aged between 30 and 39 years had the highest overall survival rate (66.7%) during a median follow-up of 47.6 months (interquartile range IQR 23.1-89.7). The same age group in the rectal cancer cohort had the lowest survival rate (31%) over a median follow-up of 54.5 (IQR 28.24-97.31) months. Leading factors affecting survival included tumor stage (HR 8.23 [4.64-14.6]; p < 0.0001), lymphovascular invasion (HR 1.88 [1.70-2.06]; p < 0.0001) and perineural invasion (HR 1.08 [1.02-1.15]; p = 0.001).

Survival trends vary within age groups of patients affected with early onset colon cancer compared to rectal cancer. Tumor stage and unfavorable pathological characteristics are the strongest factors predicting survival.

The incidence of colorectal cancer (CRC) in patients under 50 has been increasing over the past several decades. The factors underlying the increase in early onset colorectal cancer (EOCRC) are not entirely clear, although several genetic and clinical differences with late onset colorectal cancer (LOCRC) have been noted. EOCRC cases are often diagnosed at a more advanced stage, raising the possibility that these cancers progress more rapidly than LOCRC cases. The impact of age on cancer progression is an intriguing topic and numerous lines of research have found that a young tissue environment is often more promotional. In fact, a less hospitable promotional tissue environment in older individuals may offset the increased cancer risk associated with the increased mutational load associated with age. Here we address how youthful aspects of angiogenesis, the tumor immune response, and the oxidative stress response may contribute to the rapid progression of EOCRC. Understanding the factors promoting EOCRC may provide insight into why EOCRC cases are increasing.

Approximately 20% of patients with colorectal cancer (CRC) are diagnosed with a mucinous subtype of this tumor, have a worse prognosis, and often show resistance to available therapies. Molecules from the mucin family are involved in the regulation of epithelial-mesenchymal transition (EMT), which significantly determines the cancer aggressiveness. This study aimed to examine the diagnostic and prognostic significance of mucinous histology and EMT markers in patients with early-onset CRC and their association with disease severity and tumor characteristics. This study included tumor tissue samples from 106 patients diagnosed with CRC before the age of 45, 53 with mucinous and 53 with non-mucinous tumors. The EMT status was determined by immunohistochemical analysis of E-cadherin and Vimentin in tissue sections. Mucinous tumors had significantly higher Mucin-1 (p < 0.001) and cytoplasmic E-cadherin (p = 0.043) scores; they were significantly less differentiated (p = 0.007), more advanced (p = 0.027), and predominately affected right the colon (p = 0.039) compared to non-mucinous tumors. Epithelial tumors were significantly better differentiated (p = 0.034) and with less prominent tumor budding (p < 0.001) than mesenchymal tumors. Mucin-1 and Vimentin were independent predictors of tumor differentiation (p = 0.006) and budding (p = 0.001), respectively. Mucinous histology and EMT markers are significant predictors of disease severity and tumor characteristics in early-onset colorectal cancer.

Few studies have evaluated the benefits of colorectal cancer (CRC) screening integrating both non-genetic and genetic risk factors. Here, we aimed to integrate an existing non-genetic risk model (QCancer-10) and a 139-variant polygenic risk score to evaluate the effectiveness of screening on CRC incidence and mortality.

We applied the integrated model to calculate 10-year CRC risk for 430,908 participants in the UK Biobank, and divided the participants into low-, intermediate-, and high-risk groups. We calculated the screening-associated hazard ratios (HRs) and absolute risk reductions (ARRs) for CRC incidence and mortality according to risk stratification.

During a median follow-up of 11.03 years and 12.60 years, we observed 5,158 CRC cases and 1,487 CRC deaths, respectively. CRC incidence and mortality were significantly lower among screened than non-screened participants in both the intermediate- and high-risk groups [incidence: HR: 0.87, 95% confidence interval (CI): 0.81-0.94; 0.81, 0.73-0.90; mortality: 0.75, 0.64-0.87; 0.70, 0.58-0.85], which composed approximately 60% of the study population. The ARRs (95% CI) were 0.17 (0.11-0.24) and 0.43 (0.24-0.61), respectively, for CRC incidence, and 0.08 (0.05-0.11) and 0.24 (0.15-0.33), respectively, for mortality. Screening did not significantly reduce the relative or absolute risk of CRC incidence and mortality in the low-risk group. Further analysis revealed that screening was most effective for men and individuals with distal CRC among the intermediate to high-risk groups.

After integrating both genetic and non-genetic factors, our findings provided priority evidence of risk-stratified CRC screening and valuable insights for the rational allocation of health resources.

The incidence of early-onset colorectal cancer (EOCRC; diagnosed <50 years of age) is rising globally; however, the causes underlying this trend are largely unknown. CRC has strong genetic and environmental determinants, yet common genetic variants and causal modifiable risk factors underlying EOCRC are unknown. We conducted the first EOCRC-specific genome-wide association study (GWAS) and Mendelian randomization (MR) analyses to explore germline genetic and causal modifiable risk factors associated with EOCRC.

We conducted a GWAS meta-analysis of 6176 EOCRC cases and 65 829 controls from the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), the Colorectal Transdisciplinary Study (CORECT), the Colon Cancer Family Registry (CCFR), and the UK Biobank. We then used the EOCRC GWAS to investigate 28 modifiable risk factors using two-sample MR.

We found two novel risk loci for EOCRC at 1p34.1 and 4p15.33, which were not previously associated with CRC risk. We identified a deleterious coding variant (rs36053993, G396D) at polyposis-associated DNA repair gene MUTYH (odds ratio 1.80, 95% confidence interval 1.47-2.22) but show that most of the common genetic susceptibility was from noncoding signals enriched in epigenetic markers present in gastrointestinal tract cells. We identified new EOCRC-susceptibility genes, and in addition to pathways such as transforming growth factor (TGF) β, suppressor of Mothers Against Decapentaplegic (SMAD), bone morphogenetic protein (BMP) and phosphatidylinositol kinase (PI3K) signaling, our study highlights a role for insulin signaling and immune/infection-related pathways in EOCRC. In our MR analyses, we found novel evidence of probable causal associations for higher levels of body size and metabolic factors-such as body fat percentage, waist circumference, waist-to-hip ratio, basal metabolic rate, and fasting insulin-higher alcohol drinking, and lower education attainment with increased EOCRC risk.

Our novel findings indicate inherited susceptibility to EOCRC and suggest modifiable lifestyle and metabolic targets that could also be used to risk-stratify individuals for personalized screening strategies or other interventions.

Kidney cancer has become known as a metabolic disease. However, there is limited evidence linking metabolic syndrome (MetS) with kidney cancer risk. This study aimed to investigate the association between MetS and its components and the risk of kidney cancer.

UK Biobank data was used in this study. MetS was defined as having three or more metabolic abnormalities, while pre-MetS was defined as the presence of one or two metabolic abnormalities. Hazard ratios (HRs) and 95% confidence intervals (CIs) for kidney cancer risk by MetS category were calculated using multivariable Cox proportional hazards models. Subgroup analyses were conducted for age, sex, BMI, smoking status and drinking status. The joint effects of MetS and genetic factors on kidney cancer risk were also analyzed.

This study included 355,678 participants without cancer at recruitment. During a median follow-up of 11 years, 1203 participants developed kidney cancer. Compared to the metabolically healthy group, participants with pre-MetS (HR= 1.36, 95% CI: 1.06-1.74) or MetS (HR= 1. 70, 95% CI: 1.30-2.23) had a significantly greater risk of kidney cancer. This risk increased with the increasing number of MetS components (P for trend < 0.001). The combination of hypertension, dyslipidemia and central obesity contributed to the highest risk of kidney cancer (HR= 3.03, 95% CI: 1.91-4.80). Compared with participants with non-MetS and low genetic risk, those with MetS and high genetic risk had the highest risk of kidney cancer (HR= 1. 74, 95% CI: 1.41-2.14).

Both pre-MetS and MetS status were positively associated with kidney cancer risk. The risk associated with kidney cancer varied by combinations of MetS components. These findings may offer novel perspectives on the aetiology of kidney cancer and assist in designing primary prevention strategies.

During the COVID-19 pandemic, health systems, including federally qualified health centers, experienced disruptions in colorectal cancer (CRC) screening. National organizations called for greater use of at-home stool-based testing followed by colonoscopy for those with abnormal test results to limit (in-person) colonoscopy exams to people with acute symptoms or who were high risk. This stool-test-first strategy may also be useful for adults with low-risk adenomas who are due for surveillance colonoscopy. We argue that colonoscopy is overused as a first-line screening method in low- and average-risk adults and as a surveillance tool among adults with small adenomas. Yet, simultaneously, many people do not receive much-needed colonoscopies. Delivering the right screening tests at intervals that reduce the risk of CRC, while minimizing patient inconvenience and procedural risks, can strengthen health-care systems. Risk stratification could improve efficiency of CRC screening, but because models that adequately predict risk are years away from clinical use, we need to optimize use of currently available technology-that is, low-cost fecal testing followed by colonoscopy for those with abnormal test results. The COVID-19 pandemic highlighted the urgent need to adapt to resource constraints around colonoscopies and showed that increased use of stool-based testing was possible. Learning how to adapt to such constraints without sacrificing patients' health, particularly for patients who receive care at federally qualified health centers, should be a priority for CRC prevention research.

The primary benefit of post-colorectal cancer (CRC) colonoscopic surveillance is to detect and remove premalignant lesions to prevent metachronous CRC. Current guidelines for long-term colonoscopic surveillance post early age onset CRC (EOCRC) resection are based on limited evidence. The aims of this study were to assess the diagnostic yield of colonoscopic surveillance post-EOCRC resection and identify molecular and clinicopathological risk factors associated with advanced neoplasia.

A retrospective cohort study of prospectively collected data was conducted at St Mark's hospital, London, United Kingdom, for patients diagnosed with EOCRC who underwent at least one episode of post-CRC colonoscopic surveillance between 1978 and 2022. We collected clinicopathological data including tumour molecular status and neoplasia detection rates.

In total, 908 colonoscopic surveillance procedures were performed in 195 patients over 2581.3 person-years of follow-up. The diagnostic yields of metachronous CRC, advanced adenomas and non-advanced adenomas were 1.76%, 3.41% and 22.69% respectively. Sixteen patients (8.21%) developed metachronous CRC, and the majority (87.5%) were detected more than 3 years post index EOCRC diagnosis. Detection of advanced neoplasia was significantly higher in EOCRC patients with Lynch syndrome (26.15%) compared with those in whom Lynch syndrome was excluded (13.13%) (OR, 2.343; 95% CI, 1.014-5.256; p = 0.0349).

During colonoscopic surveillance post-EOCRC resection, the long-term risk of developing metachronous advanced neoplasia remains high in the context of Lynch syndrome, but this trend is not as clearly evident when Lynch syndrome has been excluded.

Early-onset prostate cancer (EOPC, ≤ 55 years) has a unique clinical entity harboring high genetic risk, but the majority of EOPC patients still substantial opportunity to be early-detected thus suffering an unfavorable prognosis. A refined understanding of age-based polygenic risk score (PRS) for prostate cancer (PCa) would be essential for personalized risk stratification.

We included 167,517 male participants [4882 cases including 205 EOPC and 4677 late-onset PCa (LOPC)] from UK Biobank. A General-, an EOPC- and an LOPC-PRS were derived from age-specific genome-wide association studies. Weighted Cox proportional hazard models were applied to estimate the risk of PCa associated with PRSs. The discriminatory capability of PRSs were validated using time-dependent receiver operating characteristic (ROC) curves with additional 4238 males from PLCO and TCGA. Phenome-wide association studies underlying Mendelian Randomization were conducted to discover EOPC linking phenotypes.

The 269-PRS calculated via well-established risk variants was more strongly associated with risk of EOPC [hazard ratio (HR) = 2.35, 95% confidence interval (CI) 1.99-2.78] than LOPC (HR = 1.95, 95% CI 1.89-2.01; I2 = 79%). EOPC-PRS was dramatically related to EOPC risk (HR = 4.70, 95% CI 3.98-5.54) but not to LOPC (HR = 0.98, 95% CI 0.96-1.01), while LOPC-PRS had similar risk estimates for EOPC and LOPC (I2 = 0%). Particularly, EOPC-PRS performed optimal discriminatory capability for EOPC (area under the ROC = 0.613). Among the phenomic factors to PCa deposited in the platform of ProAP (Prostate cancer Age-based PheWAS; https://mulongdu.shinyapps.io/proap ), EOPC was preferentially associated with PCa family history while LOPC was prone to environmental and lifestyles exposures.

This study comprehensively profiled the distinct genetic and phenotypic architecture of EOPC. The EOPC-PRS may optimize risk estimate of PCa in young males, particularly those without family history, thus providing guidance for precision population stratification.

Early-onset cancer (diagnosed under 50 years of age) is associated with aggressive disease characteristics and its rising incidence is a global concern. The association between healthy lifestyle and early-onset cancer and whether it varies by common genetic variants is unknown.

To examine the associations between genetic risk, lifestyle, and risk of early-onset cancers.

We analyzed a prospective cohort of 66,308 white British participants who were under age 50 and free of cancer at baseline in the UK Biobank.

Sex-specific composite total cancer polygenic risk scores (PRSs), a breast cancer-specific PRS, and sex-specific health-associated lifestyle scores (HLSs, which summarize smoking status, body mass index [males only], physical activity, alcohol consumption, and diet).

Hazard ratios (HRs) and 95% confidence intervals (CIs) for early-onset total and breast cancer.

A total of 1,247 incident invasive early-onset cancer cases (female: 820, male: 427, breast: 386) were documented. In multivariable-adjusted analyses with 2-year latency, higher genetic risk (highest vs. lowest tertile of PRS) was associated with significantly increased risks of early-onset total cancer in females (HR, 95% CI: 1.85, 1.50-2.29) and males (1.94, 1.45-2.59) as well as early-onset breast cancer in females (3.06, 2.20-4.25). An unfavorable lifestyle (highest vs. lowest category of HLS) was associated with higher risk of total cancer and breast cancer in females across genetic risk categories; the association with total cancer was stronger in the highest genetic risk category than the lowest: HRs in females and men were 1.85 (1.02, 3.36), 3.27 (0.78, 13.72) in the highest genetic risk category and 1.15 (0.44, 2.98), 1.16 (0.39, 3.40) in the lowest.

Both genetic and lifestyle factors were independently associated with early-onset total and breast cancer risk. Compared to those with low genetic risk, individuals with a high genetic risk may benefit more from adopting a healthy lifestyle in preventing early-onset cancer.

Colorectal cancer (CRC) is a complex disease with monogenic, polygenic and environmental risk factors. Polygenic risk scores (PRS) are being developed to identify high polygenic risk individuals. Due to differences in genetic background, PRS distributions vary by ancestry, necessitating calibration.

We compared four calibration methods using the All of Us Research Program Whole Genome Sequence data for a CRC PRS previously developed in participants of European and East Asian ancestry. The methods contrasted results from linear models with A) the entire data set or an ancestrally diverse training set AND B) covariates including principal components of ancestry or admixture. Calibration with the training set adjusted the variance in addition to the mean.

All methods performed similarly within ancestry with OR (95% C.I.) per s.d. change in PRS: African 1.5 (1.02, 2.08), Admixed American 2.2 (1.27, 3.85), European 1.6 (1.43, 1.89), and Middle Eastern 1.1 (0.71, 1.63). Using admixture and an ancestrally diverse training set provided distributions closest to standard Normal with accurate upper tail frequencies.

Although the PRS is predictive of CRC risk for most ancestries, its performance varies by ancestry. Post-hoc calibration preserves the risk prediction within ancestries. Training a calibration model on ancestrally diverse participants to adjust both the mean and variance of the PRS, using admixture as covariates, created standard Normal z-scores. These z-scores can be used to identify patients at high polygenic risk, and can be incorporated into comprehensive risk scores including other known risk factors, allowing for more precise risk estimates.

The death burden attributable to modifiable risk factors is key to colorectal cancer (CRC) prevention. This study aimed to assess the prevalence and regional distribution of attributable CRC death burden worldwide from 1990 to 2019.

We extracted data from the Global Burden of Disease Study in 2019 and assessed the mortality, age-standardized death rate (ASDR), population attributable fractions, and time trend in CRC attributable to risk factors by geography, socio-demographic index (SDI) quintile, age, and sex.

Over the past 30 years, from high to low SDI region, the number of deaths increased by 46.56%, 103.55%, 249.64%, 231.89%, 163.11%, and the average annual percentage change (AAPC) for ASDR were -1.06%, -0.01%, 1.32%, 1.19%, and 0.65%, respectively. ASDR in males was 1.88 times than in females in 2019; ASDR in males showed an increasing trend (AAPC 0.07%), whereas ASDR in females showed a decreasing trend (AAPC -0.69%) compared to figures in 1990. In 2019, from high to low SDI region, the 15-49 age group accounted for 3%, 6%, 10%, 11%, and 15% of the total population; dietary and metabolic factors contributed 43.4% and 20.8% to CRC-attributable death worldwide. From high to low SDI region, ASDRs caused by dietary and metabolic factors increased by -23.4%, -5.5%, 25.8%, 29.1%, 13.5%, and 1.4%, 33.3%, 100.8%, 128.4%, 77.7% respectively, compared to 1990.

The attributable CRC death burden gradually shifted from higher SDI to lower SDI regions. The limitation in males was more significant, and the gap is expected to be further expanded. In lower SDI regions, the death burden tended to affect younger people. The leading cause of CRC-attributable deaths was the inadequate control of dietary and metabolic risk factors.