Risk of Colorectal Cancer in Ulcerative Colitis Patients: A Systematic Review and Meta-Analysis

Abstract

Background Ulcerative colitis (UC) patients have an increased risk for the development of colorectal cancer (CRC). Our aim was to assess the risk of CRC in UC patients compared with disease extent, disease duration, and geographic variation. Methods In this systematic review and meta-analysis, we searched PubMed, scientific meetings, and the bibliographies of identified articles, with English language restrictions for studies published from 1988 to 2018, and assessed the risk of CRC in UC patients. Patients with Crohn's disease, family history of CRC, and colorectal adenomatous polyp (CAP) were excluded from this research. The study was registered with PROSPERO, number CRD42018102213. Findings We included 58 studies that included 267566 UC patients. Extensive UC and left-sided UC had a higher risk of CRC than proctitis UC. Geography also played a role in UC-associated CRC development. The time of malignant transformation in Asian UC patients started after 10-20 years of this disease duration. North American UC-associated CRC patients significantly increased in more than 30 years of this disease duration. Conclusion In a systematic review of the literature, we found that disease extent, disease duration, and geography were strong, independent risk factors in UC-associated CRC development.

Immune Effects of γδ T Cells in Colorectal Cancer: A Review

“…Inflammatory bowel diseases (IBD) including Crohn's disease (CD) and ulcerative colitis (UC) are complex chronic inflammatory disorders of unknown origin that could affect the intestinal tract (77). Colitis-associated cancer (CAC) may develop in patients with IBD, which is primarily due to chronic intestinal inflammation (78,79). It is reported that the cumulative incidence of CRC by colitis duration was 2.5% at 20 years, 7.6% at 30 years, and 10.8% at 40 years (78).…”

Colon Carcinogenesis: The Interplay Between Diet and Gut Microbiota

“…The connection between inflammation and malignant diseases has been well-established based on evidence from epidemiological, genetic, or pharmacological studies. In the case of colon malignancies, IBDs especially ulcerative colitis and Crohn's disease exhibit consistent association with an elevated risk of CRC (Choi et al, 2019;Zhou et al, 2019;Oleń et al, 2020). IBDassociated CRC is characterized by early onset (Keller et al, 2019), increased formation of synchronous, and poorly differentiated tumors (Reynolds et al, 2017) as well as elevated mortality rate (Sebastian et al, 2014), in relation to sporadic CRC.…”

In vitro models of intestinal epithelium: Toward bioengineered systems

“… 35 , 36 Moreover, as a consequence of chronic intestinal inflammation, patients with IBD are two to sixfold more likely to develop colorectal cancer than the general population. 37 , 38 Colorectal cancer is the third most common type of cancer and the fourth cancer-related cause of death worldwide, with over 1.2 million new cases and 900,000 deaths per year, with a growing incidence in developing countries. 39 The cell of origin for most colorectal cancers is thought to be a stem cell.…”