Serrated pathway: Alternative route to colorectal cancer

Figure 1 Microscopic features of serrated polyps. A: On cross section serrated crypt shows a stellate or starlike appearance; B: In longitudinal section a characteristic serrated or saw-toothed appearance can be seen.

Figure 2 Schematic representation of the sessile and traditional serrated pathways. N: Normal mucosa; ACF-Hs: Serrated hyperplastic-type aberrant crypt focus; ACF-Hns: Non-serrated hyperplastic-type aberrant crypt focus; MVHP: Microvesicular hyperplastic polyp; OIS: Oncogene-induced senescence; GCHP: Goblet cell-rich hyperplastic polyp; SSA: Sessile serrated adenoma; TSA: Traditional serrated adenoma; SSA-HGD: Sessile serrated adenoma with high grade dysplasia; TSA-HGD: Traditional serrated adenoma with high grade dysplasia; SAC: Serrated adenocarcinoma; IGFBP7: Insulin-like growth factor-binding protein 7; MAPK: Mitogen activated protein kinase-ERK pathway; MLH1: MutL homolog 1; MGMT: O-6-methylguanine-DNA methyltransferase; CIMP-H: CpG island methylator phenotype-high; CIMP-L: CpG island methylator phenotype-low; MSI-H: High-level microsatellite instability; MSI-L: Low-level microsatellite instability; MSS: Microsatellite stable.