结直肠锯齿状息肉报道课件.pptx

1、简要介绍锯齿状病变专家共识推荐规范增生性息肉(MVHP)与SSA/P的新认知传统型锯齿状腺瘤(TSA)伴异型增生简要介绍锯齿状病变专家共识推荐规范2010年在Cleveland举行，由美国胃肠病学会(ACG)支持、美国国立卫生研究院(NIH)赞助专家组成员：endoscopy, surgery, pathology, epidemiology, and/or molecular aspects ofserrated lesions and/or serrated polyposis.经与会专家组讨论15年MEDLIAN文献，形成共识报告，目的是总结锯齿状息肉病理、分子病理和内镜特征，提高这种疾

2、病威胁的意识，描述内镜特征，强调该疾病精确探查和完全切除的重要性，提供有关该病切除后处理的推荐规范。Key conclusions and recommendations of the consensus groupPathology1 Serrated lesions of the colorectum should be classified histologically as hyperplastic polyp (HP), sessile serrated adenoma/polyp(SSA/P) with or without cytologic dysplasia, or trad

3、itional serrated adenoma (TSA). Exceptions and subcategories are discussed in the text. Clinicians and pathologists within institutions should work collaboratively to achieve a common usage and understanding of terminology of serrated lesions.2 SSA/P and TSA are pre-cancerous lesions. SSA/P is the p

4、rincipal precursor of hypermethylated colorectal cancers (cancers with the CpG Island Methylator Phenotype CIMP). This pathway occurs primarily in the proximal colon.3 SSA/P is distinguished from HP pathologically by findings of crypt distortion, particularly in the crypt base, in SSA/P. We recommen

5、d that a single unequivocal architecturally distorted, dilated, and/or horizontally branched crypt, particularly if it is associated with inverted maturation, is sufficient for a diagnosis of SSA/P. Most large serrated lesions in the proximal colon are SSA/Ps.4 SSA/P with cytological dysplasia is a

6、more advanced lesion in the progression to cancer compared to SSA/P without cytologicaldysplasia.Endoscopy5 SSA/P and hyperplastic polyps in the proximal colon have a distinct endoscopic appearance, which includes a “mucus cap”, color usually similar to normal mucosa, and indistinct edges. All colon

7、oscopists should be able to recognize serrated lesions.6 Detection of proximal colon serrated lesions by individual endoscopists is highly correlated with adenoma detection. Pending development of specific detection targets for proximal colon serrated lesions, endoscopists should measure their adeno

8、ma detection rates as a check on adequate detection of serrated lesions.7 All serrated lesions proximal to the sigmoid colon should be fully resected during colonoscopy. All serrated lesions in the rectosigmoid colon 5 mm in size should be fully resected.Surveillance8 Serrated polyposis is defined b

9、y the World Health Organization (see text for details). Patients with serrated polyposis require close endoscopic follow-up with control of polyp burden by endoscopy or by surgical resection if the number, size or location of serrated polyps precludes endoscopic resection or if a cancer is diagnosed

10、.9 First degree relatives of patients with SPS should undergo colonoscopy at age 40 or 10 years before the age at diagnosis of SPS.Colonoscopy should be at 5 year intervals or more often if polyps are found.10 There are few longitudinal observational studies after removal of serrated lesions on whic

11、h recommendations for postpolypectomy surveillance can be based. Recommendations are mostly based on features of serrated lesions for which there is evidence of an association with increased risk of cancer or advanced neoplasms, including: proximal colon location, large size, increasing number, and

12、histologic features including SSA/P histology .Am J Gastroenterol, 2012 ,107(9): 13151330.序言(introduction)锯齿状病变(serrated lesions)的真正发病率，尤其是结肠近段，可能高于先前的报道；相当数量的内镜医师漏掉了半数以上的锯齿状病变。流行病学 尸解研究显示25-50%的白种成人有一个及以上锯齿状病变。内镜检出率很低。锯齿状病变最常见于乙状结肠和直肠，其分布依据组织学类型变化，70-95%的锯齿状病变为HPs，左半结肠为主；SSA/Ps占5-25%，右半结肠为主，TSA少于SS

13、A/Ps，左半结肠常见。对SSA/P的认识时间相对较短，其诊断对低年资病理医生常有困难；SSA/P诊断频率文献报道也是变化甚大。MVHP与SSA/P交界性病变依然是一个诊断问题。近年来对SSA/P的诊断阈值趋向降低，认为在MVHP背景中即使是有1个确定的结构扭曲、扩张和/或水平分支的SSA/P样隐窝，也可以诊断SSA/P(Am J Gastroenterol.2012, 107(9): 13151330)。compartmentalization aberration,CCA(Am J Surg Pathol, 2014;38:158166)A HP pSSA type 1-3(B-D) 传统

14、型锯齿状腺瘤(TSA)伴异型增生两种形态的异型增生：锯齿状异型增生和经典腺瘤性异型增生(serrated dysplasia and conventional adenomatous dysplasia)分类：TSA with serrated dysplasia,TSA with conventional adenomatous dysplasia and tubullovillous adenoma with serrated dysplasia,后一种类型含少量serrated dysplasia形态和分子病理学特征：TSA with serrated dysplasia-息肉小、与BR

15、AF突变高度相关；TSA with convetional adenomatous dysplasia and tubullovillous adenoma with serrated dysplasia，息肉较大，更多KRAS突变，后二者具有-catenin表达，而前者无表达；但是，CpG岛甲基化和BRAF突变很少见于经典腺瘤。(Modern Pathology, advance online publication, 7 March 2014)Am J Gastroenterol, 2012 ; 107(9): 13151330.不同的锯齿状病变隐窝与粘膜肌的关系模式图HP增生性息肉增生性

16、息肉SSA/PHPsMVHP(left)Hyperplastic polyp MVHPGCHPMPHPborderline sessile serrated lesionA.介于介于HP和和SSA/P之间，仅有隐窝之间，仅有隐窝扩张；扩张；B.SSA/PMucosal prolapse polyps.SSA/PExamples of study MVHP (A) and pSSAs types 1 to 3 (BD)Am J Surg Pathol 2014;38:158166SSA/PSSA/PSSA/PSSA/P 隐窝扩张和隐窝基底锯齿状SSA/PSessile serrated adenomaSessile serrated adenoma of appendixKi67显示隐窝增生区不对称SSA/P with cytological dysplasiaSSA/P with cytological dysplasiaMixed polypTSATSATSATSATSA,低倍图像，显示ECF，即隐窝呈悬浮，不与粘膜肌接触TSA.高倍显示ECF小结锯齿状息肉漏诊很多，病理和内镜医生应予以重视。HP和SSA/P是同一个形态谱系中的不同两端，二者之间是“灰区”，诊断困难大，尤其是小活检组织。TSA常伴不同类型的异型增生锯齿状息肉切除后应严格随访，谨防间隔性肠癌