OBJECTIVE: Early-onset colorectal cancer (CRC) is increasing globally. While the United States have lowered the age of initiation of screening to 45, other countries still start screening at age 50. In Taiwan, the incidence of CRC has declined in 55-74 year-olds after the initiation of screening, but still increased in those 50-54, potentially due to rising precancerous lesion incidence in 40-49 year-olds. This study aimed to explore the chronological trend of the prevalence of colorectal advanced neoplasms (AN) in the screening population aged 40-54.
METHODS: We retrospectively analyzed a screening colonoscopy cohort for prevalence of AN in average-risk subjects aged 40-54 from 2003 to 2019. Logistic regression was used to distinguish cohort effect from time-period effect on the prevalence of AN.
RESULTS: In total, 27,805 subjects (52.1% male) men were enrolled. There were notable increases in prevalence of AN in all three age groups during the 17-year span, but these were more rapid in age 40-44 (0.99% to 3.22%) and 45-49 (2.50% to 4.19%). Age 50-54 had higher risk of AN [aOR=1.62(1.19-2.19)] in 2003-2008 but not in later periods [2009-2014: aOR=1.08(0.83-1.41)] and [2015-2019: aOR=0.76(0.56-1.03)] when compared with age 45-49.
CONCLUSIONS: The prevalence of AN in age 40-54 increased in the Taiwanese population, with a later birth cohort having a higher prevalence of AN. However, the prevalence of AN in age 45-49 increased more remarkably and approximated that in age 50-54, which may justify earlier initiation of CRC screening at age 45.

Colorectal cancer that occurs before age of 50 is defined as Early-Onset Colorectal Cancer (EOCRC). Its incidence has worryingly increased since the late 90 s and is expected to keep rising in the next future, despite Late-Onset CRC (LOCRC) is decreasing worldwide. Because of this, there is an urgent need to better understand this subset of patients in order to give them the best treatment possible. However, most of the literature is retrospective and often discordant. In this review, we aim to provide a general overview of the issue, endeavoring to highlight the current available knowledge. We decided to move from the beginning, investigating risk factors and inheritance, passing through diagnosis and clinical aspects, and to conclude with the translational part, focusing on the biology of the tumor. However, lot of questions remain open, including screening age and prognosis. Indeed, young patients tend to be treated more aggressively, even if a survival benefit has not been proven yet. Every clinician should be aware of the best practice for young people, and more translational studies are awaited in order to clarify is EOCRC represents a distinct biological entity.

Evidence indicates that both vitamin D and the gut microbiome are involved in the process of colon carcinogenesis. However, it is unclear what effects supplemental vitamin D3 has on the gut microbiome and its metabolites in healthy adults. We conducted a double-blind, randomized, placebo-controlled trial to identify the acute and long-term microbiota structural and metabolite changes that occur in response to a moderate dose (4,000 IU) of vitamin D3 for 12 weeks in healthy adults. Our results demonstrated a significant increase in serum 25-hydroxy-vitamin D (25(OH)D) in the treatment group compared to placebo (P < 0.0001). Vitamin D3 significantly increased compositional similarity (P < 0.0001) in the treatment group, and enriched members of the Bifidobacteriaceae family. We also identified a significant inverse relationship between the percent change in serum 25(OH)D and microbial stability in the treatment group (R = -0.52, P < 0.019). Furthermore, vitamin D3 supplementation resulted in notable metabolic shifts, in addition to resulting in a drastic rewiring of key gut microbial-metabolic associations. In conclusion, we show that a moderate dose of vitamin D3 among healthy adults has unique acute and persistent effects on the fecal microbiota, and suggest novel mechanisms by which vitamin D may affect the host-microbiota relationship.
OBJECTIVE: Preventative measures to reduce the rise in early-onset colorectal cancer are of critical need. Both vitamin D, dietary and serum levels, and the gut microbiome are implicated in the etiology of colorectal cancer. By understanding the intimate relationship between vitamin D, the gut microbiome, and its metabolites, we may be able to identify key mechanisms that can be targeted for intervention, including inflammation and metabolic dysfunction. Furthermore, the similarity of vitamin D to cholesterol, which is metabolized by the gut microbiome, gives precedence to its ability to produce metabolites that can be further studied and leveraged for controlling colorectal cancer incidence and mortality.

UNASSIGNED: The burden of early-onset colorectal cancer (EoCRC) has been increasing among young adult populations in the U.S. The aim of this study was to investigate the relationship between the incidence and mortality of EoCRC and the supply of gastroenterology (GI) specialists and primary care physicians (PCP).
UNASSIGNED: This was an ecological study of EoCRC cases among US counties that occurred between 2014 and 2018. Data was obtained from US cancer statistics. County-level data, including sociodemographic (eg, percentage of female, non-White residents, poverty rate, rurality) and physician supply (GI specialists and PCPs) was obtained from area health resources files. We estimated linear mixed-effects models with the county as a random effect to examine the association of physician supply with 5-year average age-adjusted EoCRC incidence and mortality. Models were adjusted for aggregate county-level socioeconomic characteristics. Multicollinearity was tested through variation inflation.
UNASSIGNED: Analysis included 855 US counties. Mean age-adjusted EoCRC incidence and mortality rates between 2014-2018 were 9.5 (standard deviation [SD]: 2.7) and 2.7 (SD: 0.8) per 100,000 persons, respectively. In the adjusted model, GI supply was associated with lower EoCRC incidence (-5.6 percentage-point change per SD; 95% confidence interval, -11.0 to -0.1) but not with EoCRC mortality (P = .558). PCP supply was associated with lower EoCRC mortality (-27.0 percentage-point change per SD; 95% confidence interval, -46.1 to -7.8) but not with EoCRC incidence (P = .077).
UNASSIGNED: Greater GI specialist supply was associated with a reduction in EoCRC incidence but not improved mortality. Study findings suggest the need for early colorectal cancer screening efforts and the potential for expanding GI services and referrals in medically underserved areas.

The incidence of early-onset colorectal cancer has been rising over the last two decades. Tumors in young patients have distinct features compared to older patients. They predominantly arise in the distal colon and rectum and have poor histological features. Patients tend to present at a more advanced stage and be exposed to more aggressive management approaches; however, this has not translated into a significant survival benefit compared to their older counterparts. This chapter will share current evidence on risk factors and management options for early onset colorectal cancer with a focus on rectal cancer.

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.

UNASSIGNED: The incidence of early-onset colorectal cancer (EOCRC) has increased globally since the early 1990s. Comprehensively examining the risk factors would be helpful for risk stratification and the development of personalized colorectal cancer screening strategies.
UNASSIGNED: We performed a prospective study of the Chinese population aged 30-50 years to identify potential risk factors during a median follow-up of 9.1 years. We compared the distribution of demographic characteristics, lifestyle factors, dietary habits, and medical history among 222 EOCRC cases and 87,833 normal controls. Multivariate adjusted Cox hazard models were used for estimating EOCRC risks of each risk factor.
UNASSIGNED: Our final analyses indicated that participants with a higher body mass index (HR, 1.04; 95% CI:1.00,1.08), regular alcohol consumption (HR, 1.69; 95% CI: 1.12, 2.91), higher intake of fish (HR, 1.64; 95% CI: 1.01, 2.67), hypertension (HR, 1.99; 95% CI: 1.04, 3.81), diabetes (HR, 2.20; 95% CI: 1.08, 4.49), and first-degree relatives with cancer (HR, 1.70; 95% CI: 1.23, 2.36) were at higher risk of EOCRC.
UNASSIGNED: We identified several modifiable as well as nonmodifiable risk factors, such as higher BMI, alcohol and fish consumption, hypertension, and diabetes, were associated with EOCRC.

The incidence of early-onset colorectal cancer (EOCRC) has increased significantly worldwide. Uncovering biomarkers that are unique to EOCRC is of great importance to facilitate the prevention and detection of this growing cancer subtype. Although efforts have been made in the data curation about CRC, there is no integrated platform that gives access to data specifically related to young CRC patients. Here, we constructed a user-friendly open integrated resource called CRCDB (URL: http://crcdb-hust.com) which contains multi-omics data of 785 EOCRC, 4898 late-onset CRCs (LOCRC), and 1110 normal control samples from tissue, whole blood, platelets, and serum exosomes. CRCDB manages the differential analysis, survival analysis, co-expression analysis, and immune cell infiltration comparison analysis results in different CRC groups. Meta-analysis results were also provided for users for further data interpretation. Using the resource in CRCDB, we identified that genes associated with the metabolic process were less expressed in EOCRC patients, while up regulated genes most associated with the mitosis process might play an important role in the molecular pathogenesis of LOCRC. Survival-related genes were most enriched in oxidoreduction pathways in EOCRC while in immune-related pathways in LOCRC. With all the data gathered and processed, we anticipate that CRCDB could be a practical data mining platform to help explore potential applications of omics data and develop effective prevention and therapeutic strategies for the specific group of CRC patients.

UNASSIGNED: The incidence of early-onset colorectal cancer (EOCRC) is increasing globally. This study aims to describe the temporal trends of incidence and explore related risk exposures in early-life at the country level based on the GBD 2019.
UNASSIGNED: Data on the incidence and attributable risk factors of EOCRC were obtained from the GBD 2019. Temporal trends of age-standardized incidence were evaluated by average annual percentage change (AAPC). Early-life exposures were indicated as summary exposure values (SEV) of selected factors, SDI and GDP per capita in previous decades and at ages 0-4, 5-9, 10-14 and 15-19 years. Weighted linear or non-linear regressions were applied to evaluate the ecological aggregate associations of the exposures with incidences of EOCRC.
UNASSIGNED: The global age-standardized incidence of EOCRC increased from 3.05 (3.03, 3.07) to 3.85 (3.83, 3.86) per 100,000 during 1990 and 2019. The incidence was higher in countries with high socioeconomic levels, and increased drastically in countries in East Asia and Caribbean, particularly Jamaica, Saudi Arabia and Vietnam. The GDP per capita, SDI, and SEVs of iron deficiency, alcohol use, high body-mass index, and child growth failure in earlier years were more closely related with the incidences of EOCRC in 2019. Exposures at ages 0-4, 5-9, 10-14 and 15-19 years were also associated with the incidences, particularly for the exposures at ages 15-19 years.
UNASSIGNED: The global incidence of EOCRC increased during past three decades. The large variations at regional and national level may be related with the distribution of risk exposures in early life.

BACKGROUND: Early-onset colorectal cancer (EO-CRC) is defined as colorectal cancer diagnosed before the age of 50 years, and its incidence has been increasing over the last decade, now accounting for 10% of all new CRC diagnoses. Average-onset colorectal cancer (AO-CRC) has shown a steady decline in its incidence and related mortality over the past 20 years. The disparities in outcomes and overall survival (OS) between EO-CRC and AO-CRC are controversial. Our study compared OS and cause-specific survival (CSS) between metastatic EO-CRC (mEO-CRC) and metastatic AO-CRC (mAO-CRC) and identified the associated factors.
METHODS: Data on patient characteristics, tumor characteristics, incidence, and mortality were obtained from the SEER database from 2010 to 2020. We identified 23,278 individuals aged > 18 years with a confirmed diagnosis of all histological subtypes of metastatic CRC (M1 on TNM stage) using ICD-O-3 site codes. mEO-CRC and mAO-CRC were compared. OS distributions and CCS were analyzed using the Kaplan-Meier method and log-rank test to assess differences. A Cox regression model was used to assess the associations between variables.
RESULTS: mEO-CRC constituted 17.79% of the cases, whereas 82.21% had mAO-CRC. Most patients with mEO-CRC were 45-49 years old (47.66%), male (52.16%) and White (72.57%) and had adenocarcinoma histology (87.30%). Left colon tumors were most prevalent in both groups (40.26%) but were more prevalent in mEO-CRC patients than in mAO-CRC patients (49.63% vs. 38.23%, p < 0.001). Patients with mEO-CRC had higher OS (p < 0.001) and CSS (p < 0.001) than those with mAO-CRC. Patients with mEO-CRC also had significantly better median overall survival (30 months vs. 18 months, p < 0.001). The factors associated with worse OS included mAO-CRC (p < 0.001), mucinous adenocarcinoma (p < 0.001), male sex (p = 0.003), and a lack of surgical intervention (p < 0.001).
CONCLUSIONS: Most patients with mEO-CRC fall within the range of 45 to 49 years of age. Patients with mEO-CRC were more likely to receive cancer-directed therapy (including chemotherapy and radiotherapy) and had better OS and CSS than those with mAO-CRC. This is likely attributable to the better performance status, fewer comorbidities, and better tolerance to cancer-directed therapy in mEO-CRC patients. The factors associated with worse OS and CSS were age > 50 years, mucinous adenocarcinoma, male sex, and no surgical treatment.