1、CT虚拟结肠镜 福建医科大学附属协和医院福建医科大学附属协和医院 CT室室 2 前 言 在美国是肿瘤发病率中居第三位 2009年有近146970例新发病例 占肿瘤死亡的第二位 2009年全美有49920例死亡 超过100万的美国人患有结肠直肠癌 3 结肠直肠癌 散发散发(一般危险因素一般危险因素)(65%85%)家族史家族史(10%30%)遗传性非息肉性结肠直肠癌(HNPCC)(5%)家族性多发性腺癌(1%)罕见综合征罕见综合征(0.1%)CENTERS FOR DISEASE CONTROL AND PREVENTION 4 危险度因子-息肉 分类 异常增生 较小癌变可能 腺瘤样 大约90%
2、结肠直肠癌由腺瘤样息肉发展而来 5 结肠腺瘤进展 小腺瘤 10mm 癌 10 yrs 大多数是增生改变 通常不会发展为癌症 6 筛查的优势 预防癌症 切除癌前病变（恶性息肉）防止癌症发生 提高生存率 早期检测显著增加长期生存机会 7 筛查的优势 91.4%66.1%8.5%0204060801005-yrSurvivalLocalRegionalDistantStage of DetectionSurvival Rates by Disease Stage8 结肠直肠癌筛查率 只有40%的结肠直肠癌在早期阶段发现 近一半多一点的超过50岁的美国人有进行近期的结肠直肠癌筛查。*varies ba
3、sed on data source 9 31281634291639321741331845361905101520253035404550TotalLess than a high schooleducationNo health insurancePrevalence(%)19971999200120022004近年来光学直肠镜检查的普及率(%)的趋势,大于50岁的美国人,1997-2004*A flexible sigmoidoscopy or colonoscopy within the past five years.Note:Data from participating sta
4、tes and the District of Columbia were aggregated to represent the United States.Source:Behavioral Risk Factor Surveillance System CD-ROM(1996-1997,1999)and Public Use Data Tape(2001,2002,2004),National Center for Chronic Disease Prevention and Health Promotion,Centers for Disease Control and Prevent
5、ion and Prevention,1999,2000,2002,2003,2005.10 20168211691812221691914924051015202530TotalLess than a high schooleducationNo health insurancePrevalence(%)19971999200120022004近年来粪便潜血试验的普及率(%)的趋势,大于50岁的美国人,1997-2004*A fecal occult blood test within the past year.Note:Data from participating states and
6、 the District of Columbia were aggregated to represent the United States.Source:Behavioral Risk Factor Surveillance System CD-ROM(1996-1997,1999)and Public Use Data Tape(2001,2002,2004),National Center for Chronic Disease Prevention and Health Promotion,Centers for Disease Control and Prevention and
7、 Prevention,1999,2000,2002,2003,2005.11 结肠直肠癌筛查率低:原因(依照患者的说法)对结肠直肠癌不重视 缺乏对结肠直肠癌筛查好处的了解 害怕,难为情,不舒服 没时间 费用高 “我医生从来没跟我提到过!”12 The 2008 CRC Guidelines Update was a Joint Effort of 5 Organizations American Cancer Society U.S.Multi-Society Task Force on Colorectal Cancer American Gastroenterological Assoc
8、iation American College of Gastroenterology American Society of Gastrointestinal Endoscopists American College of Radiology 13 CRC Screening Guidelines:What Else is New?Two new tests recommended:stool DNA(sDNA)and computerized tomographic colonography(CTC)sometimes referred to as virtual colonoscopy
9、 The guidelines:establish a sensitivity threshold for recommended tests delineate important quality-related factors for each form of testing continue to emphasize options for testing An overriding goal of this update is to provide a practical guideline for physicians and the public 14 2008 CRC Scree
10、ning Guidelines Average risk adults age 50 and olderAverage risk adults age 50 and older Tests that detect adenomatous polyps and cancerTests that detect adenomatous polyps and cancer Flexible sigmoidoscopy(FSIG)every 5 years*,or Colonoscopy every 10 years,or Double contrast barium enema(DCBE)every
11、5 years*,or CT colonography(CTC)every 5 years*Tests that primarily detect cancerTests that primarily detect cancer Annual guaiac-based fecal occult blood test(gFOBT)*with high test sensitivity for cancer,or Annual fecal immunochemical test(FIT)*with high test sensitivity for cancer,or Stool DNA test
12、(sDNA)*,with high sensitivity for cancer,interval uncertain *Note:All positive screening tests should be followed up with colonoscopy 15 原 理 16 CT虚拟结肠镜(CT Colonography，CTC)17 CT虚拟结肠镜(CT Colonography，CTC)CTC 图像 光学结肠镜 18 CT Colonography 3 3-D viewD view Polyp 2 2-D viewD view Courtesy of Beth McFarlan
13、d,MD 19 CT Colonography:Rationale Allows detailed evaluation of the entire colon Minimally invasive(rectal tube for air insufflation)No sedation required A number of studies have demonstrated a high level of sensitivity for cancer and large polyps 20 CTC vs.Optical Colonoscopy:Sensitivities for All
14、Polyps Polyp SizePolyp Size 10mm 8mm 6mm CTC 92.2%92.6%85.7%Colonoscopy 88.2%89.5%90.0%Pickhardt et al,NEJM 2003 21 CTC:Additional Findings CTC identified 55 polyps not seen on initial colonoscopy 21 adenomas One 11 mm malignant polyp Extra-colonic findings 5 asymptomatic cancers Aortic aneurysms Re
15、nal and gall bladder calculi Pickhardt et al,NEJM 2003 22 CTC:Follow-up colonoscopy Indication for diagnostic/therapeutic colonoscopy varies markedly based on selected polyp size threshold Important implications for cost-effectiveness of CTC Polyp Size ThresholdPolyp Size Threshold%Requiring colonos
16、copy%Requiring colonoscopy 10mm 7.5 8mm 13.5 6mm 29.7 Pickhardt et al,NEJM 2003 23 CT Colonography:Additional Evidence A number of other studies have demonstrated a high level of sensitivity for cancer and large polyps Findings from the recently completed multi-center ACRIN trial reportedly are similar to those of Pickhardt et al Some results from this trial have been reported at medical meetings,but have not yet been published Manuscript has been prepared and is currently under review 24 CT Col