Serrated polyps of the colon and rectum： Endoscopicfeatures including image enhanced endoscopy

• 作者: Hisao Tajiri Masahiro Ikegami. Shoichi Saito
• 来源期刊: 世界胃肠内镜杂志：英文版（电子版）
• 学科: 医学
• 关键词: IMAGE ENHANCED ENDOSCOPY Hyperplasticpolyp Early COLON cancer Traditional serrated ADENOMA Sessile serrated adenoma/polyp
• 年，卷（期）: 2015,（9）
• 页码范围: 860-871
• 页数: 12页
• 分类号: R

摘要

In this review, I outline the characteristic endoscopicfindings of serrated lesions of the colorectum based onimage enhanced endoscopy （IEE）. Histopathologically,lesions with serrated structures are typically classifiedinto the following three types based hyperplasticpolyps （HPs）, traditional serrated adenomas （TSAs）,and sessile serrated adenoma/polyps （SSA/Ps）. Both HPand SSA/P often present as dark-green colors on autofluorescence imaging （AFI） colonoscopy that are similarto the normal surrounding mucosa. In contrast, TSAsoften have elevated shapes and present as magentacolors that are similar to the tubular adenomas. Thesuperficial type of TSA also includes many lesions thatpresent as magenta colors. When SSA/Ps are associatedwith cytological dysplasia, many lesions present withmagenta colors, whereas lesions that are not associatedwith cytological dysplasia present with dark-green colors.When observed via narrow band imaging （NBI）, manySSA/P include lesions with strong mucous adhesions.Because these lesions are observed with reddish mucousadhesions, we refer to them as ＂red cap sign＂ andplace such signs among the typical findings of SSA/P.Because the dilatation of the pit in SSA/P is observed asa round/oval black dot on magnified observations, werefer to this finding as Ⅱ-dilatation pit （Ⅱ-D pit） andalso positioned it as a characteristic finding of SSA/P. Incontrast, dilatations of the capillary vessels surroundingthe glands, such as those that occur in tubular adenoma,are not considered to be useful for differentiating HPsfrom SSA/Ps. However, in cases in which SSA/P isassociated with cytological dysplasia, the dilatation ofcapillary vessels is observed in the same area. Whensubmucosal layer invasion occurs in the same area, theblood flow presents with irregularities that are similarto those of common colorectal cancer at an early stageand disappears as the invasion proceeds deeply. Thesurface pattern of invasive cancer that is observed at thetumor surface is also likely t