title: Pedunculated serrated polyp with histologic features of sessile serrated adenoma: a clinicopathologic and molecular study.
abstract: In this study, we describe a previously undescribed pedunculated serrated polyp of the colon showing typical features of sessile serrated adenoma/polyp (SSA/P). All polyps were pedunculated, located in the proximal colon, small in size, and occurred in elderly patients. Histologically, the polyps showed typical features of SSA/P in the basal crypts with irregular, asymmetric expression of Ki-67. All polyps showed the BRAF-V600E mutation. The cells in the polyps did not show obvious cytologic dysplasia, prominent serration, or diffuse cytoplasmic eosinophilia with any occurrence of the so-called "ectopic crypt formation." We consider pedunculated serrated polyp showing features of SSA/P as a previously undescribed form of serrated adenoma/polyp in the spectrum of serrated neoplasia, which might represent a pedunculated variant of SSA/P or a precursor lesion of proximally located traditional serrated adenomas in the earliest stage.
authors: Department of Pathology, Daehang Hospital, Seoul, Korea. imdoc@gmail.com
authors: Mi-Jung
authors: MJ
authors: Kim
authors: Eun-Jung
authors: EJ
authors: Lee
authors: Sung-Min
authors: SM
authors: Chun
authors: Se-Jin
authors: SJ
authors: Jang
authors: Chan-Ho
authors: CH
authors: Kim
authors: Jung-Pil
authors: JP
authors: Seo
authors: Do Sun
authors: DS
authors: Kim
authors: Doo Han
authors: DH
authors: Lee
authors: Suk Hee
authors: SH
authors: Lee
authors: Eui Gon
authors: EG
authors: Youk
mesh_terms: D000236:Adenoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D003106:Colon; D003110:Colonic Neoplasms; D003111:Colonic Polyps / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques; D009154:Mutation; D011230:Precancerous Conditions / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics; D012189:Retrospective Studies
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf