Serrated lesions and serrated polyposis syndrome

Area of Science:

• Gastroenterology and Oncology
• Molecular Pathology

Background:

• The serrated pathway is a key route for colorectal cancer (CRC) development, potentially causing up to one-third of all CRCs.
• Serrated lesions, especially sessile serrated polyps (SSPs), are increasingly researched due to their distinct histological and molecular profiles.
• These lesions carry carcinogenic risk via BRAF, KRAS, and CpG island methylator phenotype (CIMP) mutations.

Purpose of the Study:

• To highlight the significance of serrated lesions in colorectal carcinogenesis.
• To emphasize the challenges and importance of endoscopic identification and histological diagnosis of serrated lesions.
• To underscore the clinical implications of traditional serrated adenomas (TSAs) and hyperplastic polyps (HPs) in CRC risk and management.

Main Methods:

• Review of current research on serrated pathway lesions.
• Analysis of histological and molecular characteristics of serrated polyps.
• Discussion of endoscopic identification, resection, and diagnostic criteria.

Main Results:

• Serrated lesions, particularly SSPs, possess specific molecular (BRAF, KRAS, CIMP) and histological features linked to CRC.
• Endoscopic detection and adequate tissue sampling for diagnosis of serrated lesions pose challenges.
• Traditional serrated adenomas (TSAs) represent the most advanced form, indicating a higher CRC risk and necessitating vigilant follow-up and family screening.

Conclusions:

• Accurate knowledge and standardized criteria for endoscopic description and histological diagnosis of serrated lesions are essential.
• Effective management of serrated lesions, especially TSAs, is critical for CRC prevention.
• Ongoing research is expected to further elucidate the etiopathogenesis of serrated pathway colorectal cancers.