Endoscopic and molecular characterization of colorectal sessile serrated adenoma/polyps with cytologic dysplasia.

Sessile serrated adenoma/polyps (SSA/Ps), which are precursor lesions of colorectal cancer (CRC) with BRAF mutation and the CpG island methylator phenotype (CIMP), develop cytologic dysplasia (CD) during the progression of colorectal tumorigenesis. In the present study we aimed to clarify the endoscopic and molecular signatures of SSA/Ps, with and without CD. A series of 208 serrated lesions, including 41 hyperplastic polyps, 90 SSA/Ps, 33 SSA/Ps with CD, and 44 traditional serrated adenomas, were observed and resected using magnifying endoscopy. BRAF and KRAS mutations and methylation of CIMP markers (MINT1, MINT2, MINT12, MINT31, and p16) were analyzed through pyrosequencing. Molecular alterations were then compared with endoscopic and pathologic characteristics. Among SSA/Ps without CD, the Type II-Open pit pattern (Type II-O), BRAF mutation, and CIMP were tightly associated with a proximal colon location. SSA/Ps in the distal colon infrequently exhibited Type II-O and CIMP. By contrast, most SSA/Ps with CD showed Type II-O plus adenomatous pit patterns (Type III or IV), BRAF mutation, and CIMP, irrespective of their locations. Our results suggest that the Type II-O plus III/IV pit pattern is a common feature of SSA/Ps with CD in both the proximal and distal colon and that this pit pattern is a hallmark of serrated lesions at high risk of developing into CRCs.

Tanaka Y ，Yamano HO ，Yamamoto E ，Matushita HO ，Aoki H ，Yoshikawa K ，Takagi R ，Harada E ，Nakaoka M ，Yoshida Y ，Eizuka M ，Sugai T ，Suzuki H ，Nakase H ... -  《-》

Molecular features of colorectal hyperplastic polyps and sessile serrated adenoma/polyps from Korea.

Kim KM ，Lee EJ ，Ha S ，Kang SY ，Jang KT ，Park CK ，Kim JY ，Kim YH ，Chang DK ，Odze RD ... -  《-》

Endoscopic diagnosis of sessile serrated adenoma/polyp with and without dysplasia/carcinoma.

Murakami T ，Sakamoto N ，Nagahara A 《-》

Subtypes of the Type II Pit Pattern Reflect Distinct Molecular Subclasses in the Serrated Neoplastic Pathway.

Aoki H ，Yamamoto E ，Yamano HO ，Sugai T ，Kimura T ，Tanaka Y ，Matsushita HO ，Yoshikawa K ，Takagi R ，Harada E ，Nakaoka M ，Yoshida Y ，Harada T ，Sudo G ，Eizuka M ，Yorozu A ，Kitajima H ，Niinuma T ，Kai M ，Nojima M ，Suzuki H ，Nakase H ... -  《-》

Comparison of microsatellite instability, CpG island methylation phenotype, BRAF and KRAS status in serrated polyps and traditional adenomas indicates separate pathways to distinct colorectal carcinoma end points.

O'Brien MJ ，Yang S ，Mack C ，Xu H ，Huang CS ，Mulcahy E ，Amorosino M ，Farraye FA ... -  《AMERICAN JOURNAL OF SURGICAL PATHOLOGY》