Serrated colorectal cancer: Molecular classification, prognosis, and response to chemotherapy

Figure 1 Types of serrated polyps. Serrated polyps can be divided into four types: hyperplastic polyps (HPs), sessile serrated adenomas (SSAs), traditional serrated adenomas, and mixed polyps (MPs). The polyps can also be genetically characterized according to their CIMP, BRAF, KRAS, and MSI status, and certain patterns are found frequently for each category of polyp. Both microvesicular hyperplastic polyps (MVHPs), which are an HP subset, and SSAs have BRAF mutations more often than KRAS mutations. Conversely, goblet cell hyperplastic polyps (GCHPs), another HP subset, more frequently show KRAS mutations. BRAF mutations often correlate with high-grade CIMP CRC, whereas KRAS-mutated serrated polyps are more commonly found in low-grade CIMP. MPHP: Mucin-poor hyperplastic polyp.