From bycatch to target Pathogenesis and clinical implications of the serrated pathway to colorectal cancer

Colorectal cancer is one of the leading causes of the death worldwide. Prevention of colorectal cancer could be established by detecting and removing its precursors lesions: colonic polyps. Besides adenomas, up to 30% of all colorectal cancers (CRCs) arise from precursors via the serrated pathway. Since two decades only, these serrated polyps are no longer considered as innocent bycatch of colonoscopy, but evidence showed that these are potentially malignant polyps that should be removed. Given the critical impact on the prevention of CRC, our understanding of serrated polyps is overdue and among clinicians confusion still prevails around terminology, classification and risk stratification of serrated polyps. Detection and complete resection of serrated polyps are demanding tasks for endoscopists, and suboptimal practice may result in interval post-colonoscopy CRCs (iPCCRCs). In this thesis, we aimed to expand our understanding of the pathogenesis and clinical implications of the serrated pathway.