結(jié)直腸鋸齒狀息肉報道

1、簡要介紹鋸齒狀病變專家共識推薦規(guī)范 2010年在Cleveland舉行，由美國胃腸病學(xué) 會(ACG)支持、美國國立衛(wèi)生研究院(NIH) 贊助 專家組成員：endoscopy, surgery, pathology, epidemiology, and/or molecular aspects of serrated lesions and/or serrated polyposis. 經(jīng)與會專家組討論15年MEDLIAN文獻，形 成共識報告，目的是總結(jié)鋸齒狀息肉病理 、分子病理和內(nèi)鏡特征，提高這種疾病威 脅的意識，描述內(nèi)鏡特征，強調(diào)該疾病精 確探查和完全切除的重要性，提供有關(guān)該 病切除后處理的

2、推薦規(guī)范。 Key conclusions and recommendations of the consensus group Pathology 1 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 traditional serrated adenoma (TSA). Exceptions

3、 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 principal precursor of hypermethylated col

4、orectal 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 recommend that a single unequivocal architectura

5、lly 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 more advanced lesion in the progression

6、 to cancer compared to SSA/P without cytological dysplasia. Endoscopy 5 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 colonoscopists should be able to recogniz

7、e 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 adenoma detection rates as a check on ad

8、equate 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. Surveillance 8 Serrated polyposis is defined by the World Health Organization

9、(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. 9 First degree relatives of p

10、atients 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 which recommendations for postpo

11、lypectomy 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 histologic features includin

12、g SSA/P histology . Am J Gastroenterol, 2012 ,107(9): 13151330. 序言(introduction) 鋸齒狀病變(serrated lesions)的真正發(fā)病率，尤其 是結(jié)腸近段，可能高于先前的報道；相當數(shù)量的 內(nèi)鏡醫(yī)師漏掉了半數(shù)以上的鋸齒狀病變。 流行病學(xué) 尸解研究顯示25-50%的白種成人有一 個及以上鋸齒狀病變。內(nèi)鏡檢出率很低。鋸齒狀 病變最常見于乙狀結(jié)腸和直腸，其分布依據(jù)組織 學(xué)類型變化，70-95%的鋸齒狀病變?yōu)镠Ps，左半 結(jié)腸為主；SSA/Ps占5-25%，右半結(jié)腸為主，TSA 少于SSA/Ps，左半結(jié)腸常見。 對SSA

13、/P的認識時間相對較短，其診斷對低 年資病理醫(yī)生常有困難； SSA/P診斷頻率文獻報道也是變化甚大。 MVHP與SSA/P交界性病變依然是一個診斷 問題。 近年來對SSA/P的診斷閾值趨向降低，認為 在MVHP背景中即使是有1個確定的結(jié)構(gòu)扭 曲、擴張和/或水平分支的SSA/P樣隱窩，也 可以診斷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) 傳統(tǒng)型鋸齒狀腺

14、瘤(TSA)伴異型增生 兩種形態(tài)的異型增生：鋸齒狀異型增生和經(jīng) 典腺瘤性異型增生(serrated dysplasia and conventional adenomatous dysplasia) 分類：TSA with serrated dysplasia,TSA with conventional adenomatous dysplasia and tubullovillous adenoma with serrated dysplasia, 后一種類型含少量serrated dysplasia 形態(tài)和分子病理學(xué)特征： TSA with serrated dysplasia-息肉小、與

15、BRAF突變高度相關(guān)；TSA with convetional adenomatous dysplasia and tubullovillous adenoma with serrated dysplasia，息肉較大 ，更多KRAS突變，后二者具有-catenin表 達，而前者無表達；但是，CpG島甲基化和 BRAF突變很少見于經(jīng)典腺瘤。 (Modern Pathology, advance online publication, 7 March 2014) Am J Gastroenterol, 2012 ; 107(9): 13151330. 不同的鋸齒狀病變隱窩與粘膜肌的關(guān)系模式圖 H

16、P 增生性息肉增生性息肉 SSA/P HPsMVHP(left) Hyperplastic polyp MVHP GCHP MPHP borderline sessile serrated lesion A.介于介于HP和和SSA/P之間，僅有隱窩之間，僅有隱窩 擴張；擴張；B.SSA/P Mucosal prolapse polyps. SSA/P Examples of study MVHP (A) and pSSAs types 1 to 3 (BD) Am J Surg Pathol 2014;38:158166 SSA/P SSA/PSSA/P SSA/P 隱窩擴張和隱窩基底鋸齒狀 SSA/P Sessile serrated adenoma Sessile serrated adenoma of appendix Ki67顯示隱窩增生區(qū)不對稱 SSA/P with cytological dysplasia SSA/P with cytological dysplasia Mixed polyp TSA TSA TSA TSA TSA,低倍圖像，顯