| Theme | Serrated polyp of the colon, including large hyperplastic polyp | |
|---|---|---|
| Title | BRAF mutation and CpG island methylation : an alternative pathway for colorectal cancer | |
| Publish Date | 2006/07 | |
| Author | Takeshi Kambara | Department of Gastroenterological Surgery and Surgical Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences |
| Author | Noriaki Tanaka | Department of Gastroenterological Surgery and Surgical Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences |
| Author | Nagahide Matsubara | Department of Gastroenterological Surgery and Surgical Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences |
| [ Summary ] | Advanced understanding of the molecular basis of colorectal cancer (CRC) has shed a new light on the nature of hyperplastic polyps (HPs) and invite a reappraisal of our insights on clinical gastroenterology. There is increasing evidence that some hyperplastic-like polyps are precursor lesions in the proximal HP-serrated adenoma pathway, which is independent of the classical adenoma to carcinoma sequence. A recently recognized lesion is a HP variant, characterized by relatively large size, atypical histology and proximal location in the colorectum, which has been described as a sessile serrated adenoma (SSA). SSAs may be precursor lesions for most microsatellite unstable-high (MSI-H) CRCs, displaying the CpG island methylator phenotype (CIMP). The BRAF activating mutation and DNA methylation, which result in the inhibition of apoptosis via acquired mutator and suppressor gene inactivation, may be key genetic events in initiation of this pathway. The purpose of this article is to provide a conceptual framework for understanding the serrated pathway and recommendations for clinical management of these potentially aggressive HPs. | |