Prevalence and Characteristics of Colorectal Serrated Polyps

Colorectal serrated polyps (SP) are precancerous lesions characterized by a saw-tooth appearance in the colonic epithelium that contribute to colorectal cancer (CRC) development via the serrated pathway.CRC is the third most common cancer worldwide and the second most prevalent in Korea.The 2019 World Health Organization classification categorizes SP into hyperplastic polyps, sessile serrated lesions (SSL), SSL with dysplasia, and traditional serrated adenomas.The prevalence of SP ranges from 9 to 21%, with no significant increase with age, particularly among individuals aged < 50 years.The prevalence of SSL is slightly higher than that of traditional adenomas in women.Pathologically, SP develop through BRAF and KRAS mutations and CpG island methylation, accounting for 15 to 30% of CRC cases.SSL-associated cancers can progress rapidly and have a higher risk of lymph node invasion than conventional adenomas, thereby complicating early detection during colonoscopy.These findings highlight the importance of accurate identification and monitoring, especially in younger populations where prevalence is increasing.Thus, further studies are needed to optimize the screening guidelines for SP in younger adults.