Novel Methods of Risk Stratifying Patients for Metachronous, Pre-Malignant Colorectal Polyps: A Systematic Review

Despite conventional measures of future polyp risk (histology, dysplasia, size, number), surveillance places a burden on patients and colonoscopy services. We aimed to review novel risk stratification techniques.A systematic literature review was performed for studies using genomics, transcriptomics, IHC or microbiome as markers of metachronous polyp risk.4165 papers underwent title, 303 abstract and 215 full paper review. 25 papers were included. 49 mutations/ SNPs/ haplotypes in 23 genes/ chromosomal regions (KRAS, APC, EGFR, COX1/2, IL23R, DRD2, CYP2C9/24A1/7A1, UGT1A6, ODC, ALOX12/15, PGDH, SRC, IGSF5, KCNS3, EPHB1/ KY, FAM188b, 3p24.1, 9q33.2, 13q33.2) correlated with metachronous adenoma / advanced adenoma risk. Expression levels of 6 proteins correlated with metachronous adenoma (p53, β-catenin, COX2, Adnab-9, ALDH1A1) or sessile serrated polyp (ANXA10) risk.Although genomic and IHC markers correlated with metachronous polyp risk, it seems likely that a panel of novel markers will be required to refine this risk.