Background: The incidence of early-onset colorectal cancer (CRC) is increasing. Many guidelines recommend initiating screening at 45 years. This study investigated the detection rate of advanced colorectal neoplasm (ACRN) by using fecal immunochemical tests (FITs) in individuals aged 40–49 years. Methods: PubMed, Embase, and Cochrane Library databases were searched from inception to May 2022. The primary outcomes were the detection rates and positive predictive values of FITs for ACRN and CRC in people aged 40–49 (younger age group) and ≥50 years (average risk group). Results: Ten studies with 664,159 FITs were included. The FIT positivity rate was 4.9% and 7.3% for the younger age and average risk groups, respectively. Younger individuals with positive FIT results had significantly higher risks of ACRN (odds ratio [OR] 2.58, 95% confidence interval [CI] 1.79–3.73) or CRC (OR 2.86, 95% CI 1.59–5.13) than did individuals in the average-risk group, regardless of FIT results. Individuals aged 45–49 years with positive FIT results had a similar risk of ACRN (OR 0.80, 95% CI 0.49–1.29) to that of people aged 50–59 years with positive FIT results, although significant heterogeneity was observed. The positive predictive values of the FIT were 10–28.1% for ACRN and 2.7–6.8% for CRC in the younger age group. Conclusion: The detection rate of ACRN and CRC based on FITs in individuals aged 40–49 years is acceptable, and the yield of ACRN might be similar between individuals aged 45–49 and 50–59 years. Further prospective cohort and cost-effective analysis are warranted.

INTRODUCTION: Postcolonoscopy colorectal cancers (PCCRCs) are an adverse outcome associated with missed lesions and incomplete polypectomy. However, their molecular features have not been systematically reviewed. METHODS: We searched PubMed, Embase, and Cochrane Library databases from inception to April 2024. Studies examining the molecular characteristics of PCCRCs, including microsatellite instability (MSI), CpG island methylation phenotype (CIMP), genetic mutations, and chromosomal alterations were regarded as eligible. RESULTS: In total, 15 studies encompassing 11 cohorts, with 2,143 PCCRC and 19,036 sporadic colorectal cancer (SCRC) cases, were analyzed. Compared with SCRC, PCCRC was associated with older age (standardized mean difference 0.29, 95% confidence interval [CI] 0.20–0.38) and more proximal lesions (odds ratio [OR] 2.08, 95% CI 1.91–3.63). Molecularly, PCCRCs were more likely to exhibit MSI (OR 2.28, 95% CI 1.69–3.08), CIMP (OR 2.10, 95% CI 1.39–3.18), and BRAF mutations (OR 1.74, 95% CI 1.22–2.49) but were less likely to exhibit KRAS mutations (OR 0.63, 95% CI 0.45–0.87). Furthermore, MSI was strongly correlated with BRAF mutation (OR 9.36, 95% CI 5.11–17.16) and proximal lesions (OR 6.16, 95% CI 3.74–10.16) in a pooled analysis. Although the pooled 5-year overall survival rate was similar between PCCRC and SCRC cases (hazard ratio 1.03, 95% CI 0.64–1.66), PCCRCs exhibited worse survival compared with screening-detected ones (hazard ratio 1.65, 95% CI 1.46–1.86). DISCUSSION: Clinical and molecular features indicate that PCCRCs are more likely to be associated with the serrated pathway than with SCRC. Enhancing the detection of clinically significant serrated lesions may improve the efficacy of CRC screening.

INTRODUCTION: The incidence of early-onset colorectal cancer is increasing. This study explored the feasibility of fecal immunochemical test (FIT) and risk factors for predicting colorectal neoplasm in younger adults. METHODS: This single-center study included 6,457 participants who underwent health examination from 2013 to 2016 including index colonoscopy (3,307 individuals aged 30–49 years as the younger adult group and 3,150 aged ≥50 years as the average-risk group). Primary outcomes were adenoma detection rate (ADR) and advanced ADR (AADR). Findings of younger participants were stratified by the results of FIT and clinical risk factors and were compared with those of the average-risk group. RESULTS: Among participants aged 30–49 years, a positive FIT was associated with significantly higher ADR (28.5% vs 15.5, P < 0.001) and AADR (14.5% vs 3.7%, P < 0.001) than a negative FIT. Moreover, a positive FIT was associated with higher AADR in younger participants than in average-risk counterparts (14.5% vs 9.8%, P = 0.028). Although no single risk factor predicted FIT positivity in younger participants, nonalcoholic fatty liver disease was independently associated with higher ADR (odds ratio = 2.60, 95% confidence interval = 1.27–5.34, P = 0.001), and metabolic syndrome was independently predictive of higher AADR in younger participants than in average-risk participants (odds ratio = 3.46, 95% confidence interval = 1.66–7.21, P = 0.001). DISCUSSION: A positive FIT in people aged 30–49 years implies a higher risk of colorectal neoplasm, particularly among patients with nonalcoholic fatty liver disease and metabolic syndrome.

Backgroundand objectives: Patients with BRAF-mutated metastatic colorectal cancer have considerably poorer responses to conventional systemic treatment. The real-world effects of triplet therapy with BRAF, mitogen-activated protein kinase kinase, and epidermal growth factor receptor inhibitors in Asia have not been well-reported. Materials and Methods: This single-center case series included patients with BRAF-mutated metastatic colorectal cancer undergoing triplet therapy after failure of prior systemic treatment from 2016 to 2020. The primary outcome was progression-free survival, and secondary outcomes were overall survival, response rate, disease control rate, and adverse events. Results: Nine eligible patients with BRAF-mutated metastatic colorectal cancer receiving triplet therapy were enrolled, with a median follow-up time of 14.5 months (range, 1–26). Most patients (88.8%) had two or more prior systemic treatments, and the triplet regimen was mainly dabrafenib, trametinib, and panitumumab. The overall response rate and disease control rate were 11.1% and 33.3%, respectively. Median progression-free survival and overall survival were 2.9 and 7.4 months, respectively, and a trend toward better overall survival was found with left-sided metastatic colorectal cancer compared with right-sided disease (9.2 vs. 6.9 months, p = 0.093). Adverse events were mostly Grade 1–2, including nausea, hypertension, gastrointestinal symptoms, and skin disorders. Conclusions: In this single-center case series, triplet therapy with BRAF, mitogen-activated protein kinase kinase, and epidermal growth factor receptor inhibitors in BRAF-mutated metastatic colorectal cancer had an acceptable safety profile and reasonable efficacy.