Colonoscopy vs the Fecal Immunochemical Test: Which is Best?

Colonoscopy Remains an Important Option for Primary Screening for Colorectal Cancer

Colonoscopy remains the most commonly used colorectal cancer screening test in the United States. A substantial portion of the screening population value the high sensitivity of colonoscopy for precancerous colorectal lesions of all sizes, which allows it to be performed at 10 year intervals in average-risk persons with negative examinations. Emerging evidence supports the eventual endorsement of 15 year intervals for patients with normal examinations. Considerable evidence supports an impact of colonoscopy on colorectal cancer incidence and mortality, including a randomized controlled trial of colonoscopy vs. no screening, numerous case-control and cohort studies, an impact of fecal blood testing on cancer incidence, and the impact of one randomized controlled trial of flexible sigmoidoscopy on proximal colon cancer incidence. Colonoscopy is the gold standard for detection of colorectal precancerous lesions, and continues to evolve with regard to sensitivity for precancerous lesions and the effectiveness and safety of precancerous lesion resection. Gains in detection of precancerous lesions have followed from a robust movement to improve colonoscopy quality, and development of non-device techniques such as patient rotation during withdrawal, water exchange colonoscopy, and double examination of one or more colonic segments. Further, development of devices to improve mucosal exposure during withdrawal (e.g. Endocuff Vision, distal cap attachment, and Computer-Aided Quality), and devices that highlight flat lesions (e.g. chromoendoscopy, electronic chromoendoscopy, and Computer-Aided Detection) have created opportunities to achieve very high levels of detection and thereby increase the protective benefits of colonoscopy. Further, colonoscopy resection safety has improved via the widespread use of cold resection for lesions < 10 mm in size, as well as sessile serrated lesions of all sizes. Colonoscopy can be offered to patients as one of multiple options for screening, or as the test of choice for patients with the highest pre-screening probability of cancer and precancerous lesions, or as the first test offered followed by offers of other screening tests if colonoscopy is declined (sequential offers of screening). Sequential offers of screening result in overall adherence to screening similar to offering multiple options, but with a higher fraction of patients undergoing colonoscopy. Given the long-lasting protective effects of colonoscopy and its improving effectiveness and safety, colonoscopy remains a useful option for primary average-risk colorectal cancer screening.

Does Colonoscopy as a First Screening Test Still Make Sense?-Counterpoint

Colonoscopy has been widely regarded as the gold standard for its high diagnostic accuracy and preventive potential. However, its invasive nature, high cost, and suboptimal participation rates limit its utility at the population level. Non-invasive screening tests, notably the fecal immunochemical test (FIT) and multitarget stool DNA tests, present promising alternatives that may improve screening participation and reduce barriers to participation. Among these, FIT has demonstrated a consistent advantage in enhancing participation, which subsequently contributes to better long-term outcomes in CRC prevention. FIT-based two-step screening offers several practical advantages, including cost-effectiveness, non-invasiveness, and greater flexibility. Moreover, the quantitative nature of FIT allows for adjustable sensitivity thresholds and the ability of risk stratification, making it adaptable across diverse populations and scenarios. Through serial testing, FIT can increase cumulative detection rates over time. This approach facilitates the identification of high-risk individuals, allowing for more judicious use of colonoscopy resources and reducing unnecessary invasive procedures, especially among low-risk populations. Notably, evidence indicates that participation to FIT-based screening is consistently higher than to colonoscopy, which enhances the detection of early-stage cancers and advanced adenomas in the long run. Given the constraints of limited endoscopic capacity, the aging population, and the recent lowering of the recommended screening age due to the rising incidence of early-onset CRC, FIT emerges as a practical, flexible solution. The role of two-step FIT screening in improving participation and enabling risk-stratified, personalized approaches to CRC prevention is pivotal, advocating for its expanded integration into future screening paradigms.

Unraveling the Regulatory Role of HuR/microRNA Axis in Colorectal Cancer Tumorigenesis

Colorectal cancer (CRC) remains a significant global health burden with high incidence and mortality. MicroRNAs (miRNAs) are small non-protein coding transcripts, conserved throughout evolution, with an important role in CRC tumorigenesis, and are either upregulated or downregulated in various cancers. RNA-binding proteins (RBPs) are known as essential regulators of miRNA activity. Human antigen R (HuR) is a prominent RBP known to drive tumorigenesis with a pivotal role in CRC. In this review, we discuss the regulatory role of the HuR/miRNA axis in CRC. Interestingly, miRNAs can directly target HuR, altering its expression and activity. However, HuR can also stabilize or degrade miRNAs, forming complex feedback loops that either activate or block CRC-associated signaling pathways. Dysregulation of the HuR/miRNA axis contributes to CRC initiation and progression. Additionally, HuR-miRNA regulation by other small non-coding RNAs, circular RNA (circRNAs), or long-non-coding RNAs (lncRNAs) is also explored here. Understanding this HuR-miRNA interplay could reveal novel biomarkers with better diagnostic or prognostic accuracy.

Early diagnostic strategies for colorectal cancer

At present, cancer is still an important factor threatening human health. Colorectal cancer (CRC) is one of the top three most common cancers worldwide and one of the deadliest malignancies in humans. The latest data showed that CRC incidence and mortality rank third and second, respectively, among global malignancies. Early and accurate diagnosis is crucial to reduce the morbidity, mortality and improve survival of patients with CRC, but the current early diagnostic methods have limitations. The effectiveness and compliance of diagnostic methods have a certain impact on whether people choose screening. In this editorial, we explore strategies for the early diagnosis of CRC, including stool-based, blood-based, direct visualization, and imaging examinations.