2022年醫(yī)學(xué)專題-CT虛擬結(jié)腸鏡

1、CT虛擬(xn)結(jié)腸鏡福建醫(yī)科大學(xué)附屬(fsh)協(xié)和醫(yī)院 CT室第一頁，共二十七頁。前 言在美國是腫瘤發(fā)病率中居第三位2009年有近146970例新發(fā)病例(bngl)占腫瘤死亡的第二位2009年全美有49920例死亡超過100萬的美國人患有結(jié)腸直腸癌第二頁，共二十七頁。2結(jié)腸(jichng)直腸癌 散發(fā) (一般危險(wixin)因素) (65%85%)家族史(10%30%)遺傳性非息肉(xru)性結(jié)腸直腸癌 (HNPCC) (5%)家族性多發(fā)性腺癌(1%)罕見綜合征 (0.1%)CENTERS FOR DISEASE CONTROLAND PREVENTION第三頁，共二十七頁。3危險度因子(

2、ynz)- 息肉分類異常增生 較小癌變可能腺瘤樣大約90%結(jié)腸直腸癌由腺瘤樣息肉(xru)發(fā)展而來第四頁，共二十七頁。4結(jié)腸(jichng)腺瘤進展小腺瘤 10mm 癌10 yrs 大多數(shù)是增生改變通常不會發(fā)展為癌癥第五頁，共二十七頁。5篩查的優(yōu)勢(yush)預(yù)防癌癥切除癌前病變（惡性息肉）防止癌癥發(fā)生提高生存率早期檢測顯著增加長期(chngq)生存機會第六頁，共二十七頁。6篩查的優(yōu)勢(yush)第七頁，共二十七頁。7結(jié)腸(jichng)直腸癌篩查率只有40%的結(jié)腸直腸癌在早期(zoq)階段發(fā)現(xiàn)近一半多一點的超過50歲的美國人有進行近期的結(jié)腸直腸癌篩查。*varies based on dat

3、a source第八頁，共二十七頁。8近年來光學(xué)(gungxu)直腸鏡檢查的普及率 (%)的趨勢, 大于50歲的美國人, 1997-2004*A flexible sigmoidoscopy or colonoscopy within the past five years. Note: Data from participating states and the District of Columbia were aggregated to represent the United States. Source: Behavioral Risk Factor Surveillance Sys

4、tem 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 Prevention, 1999, 2000, 2002, 2003, 2005. 第九頁，共二十七頁。9近年來糞便潛血試驗(shyn)的普及率 (%)的趨勢, 大于50歲的美國人, 1997-2004*A fecal

5、occult blood test within the past year. Note: Data from participating states 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 Chron

6、ic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention and Prevention, 1999, 2000, 2002, 2003, 2005. 第十頁，共二十七頁。10結(jié)腸(jichng)直腸癌篩查率低:原因 (依照患者的說法)對結(jié)腸直腸癌不重視缺乏對結(jié)腸直腸癌篩查好處(ho chu)的了解害怕, 難為情, 不舒服沒時間費用高“我醫(yī)生從來沒跟我提到過!”第十一頁，共二十七頁。11The 2008 CRC Guidelines Update was a Joint Effor

7、t of 5 OrganizationsAmerican Cancer SocietyU. S. Multi-Society Task Force on Colorectal CancerAmerican Gastroenterological AssociationAmerican College of GastroenterologyAmerican Society of Gastrointestinal EndoscopistsAmerican College of Radiology第十二頁，共二十七頁。12CRC Screening Guidelines: What Else is

8、New?Two new tests recommended: stool DNA (sDNA) and computerized tomographic colonography (CTC) sometimes referred to as virtual colonoscopyThe guidelines: establish a sensitivity threshold for recommended testsdelineate important quality-related factors for each form of testing continue to emphasiz

9、e options for testingAn overriding goal of this update is to provide a practical guideline for physicians and the public第十三頁，共二十七頁。132008 CRC Screening GuidelinesAverage risk adults age 50 and olderTests that detect adenomatous polyps and cancer Flexible sigmoidoscopy (FSIG) every 5 years*, or Colon

10、oscopy every 10 years, or Double contrast barium enema (DCBE) every 5 years*, or CT colonography (CTC) every 5 years* Tests 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 te

11、st sensitivity for cancer, or Stool DNA test (sDNA)*, with high sensitivity for cancer, interval uncertain *Note: All positive screening tests should be followed up with colonoscopy第十四頁，共二十七頁。14原 理第十五頁，共二十七頁。15CT虛擬(xn)結(jié)腸鏡 ( CT Colonography，CTC)第十六頁，共二十七頁。16CT虛擬(xn)結(jié)腸鏡 ( CT Colonography，CTC)CTC 圖像(t

12、xin)光學(xué)(gungxu)結(jié)腸鏡第十七頁，共二十七頁。17CT Colonography 3-D viewPolyp2-D viewCourtesy of Beth McFarland, MD第十八頁，共二十七頁。18CT Colonography: RationaleAllows detailed evaluation of the entire colonMinimally invasive (rectal tube for air insufflation) No sedation required A number of studies have demonstrated a hig

13、h level of sensitivity for cancer and large polyps第十九頁，共二十七頁。19CTC vs. Optical Colonoscopy: Sensitivities for All PolypsPolyp Size10mm8mm6mmCTC92.2%92.6%85.7%Colonoscopy88.2%89.5%90.0%Pickhardt et al, NEJM 2003第二十頁，共二十七頁。20CTC: Additional FindingsCTC identified 55 polyps not seen on initial colonosc

14、opy 21 adenomasOne 11 mm malignant polypExtra-colonic findings5 asymptomatic cancersAortic aneurysmsRenal and gall bladder calculiPickhardt et al, NEJM 2003第二十一頁，共二十七頁。21CTC: Follow-up colonoscopyIndication for diagnostic/therapeutic colonoscopy varies markedly based on selected polyp size threshold

15、Important implications for cost-effectiveness of CTCPolyp Size Threshold% Requiring colonoscopy10mm7.58mm13.56mm29.7Pickhardt et al, NEJM 2003第二十二頁，共二十七頁。22CT Colonography: Additional EvidenceA number of other studies have demonstrated a high level of sensitivity for cancer and large polypsFindings

16、from the recently completed multi-center ACRIN trial reportedly are similar to those of Pickhardt et alSome results from this trial have been reported at medical meetings, but have not yet been publishedManuscript has been prepared and is currently under review第二十三頁，共二十七頁。23CT Colonography: Limitati

17、ons Requires full bowel prep (which most patients find to be the most unpleasant aspect of colonoscopy)Colonoscopy is required if abnormalities detected, sometimes necessitating a second bowel prepExtra-colonic findings can lead to additional testing (may have both positive and negative implications

18、)Controversy regarding management of small polyps, sensitivity for “flat polyps”Radiation exposureSteep learning curve for radiologistsLimited availability to high quality exams in many parts of the countryMost insurers do not currently cover CTC as a screening modality 第二十四頁，共二十七頁。242008 CRC Guidel

19、ines continue to emphasize options because:Evidence does not yet support any single test as “best”Uncertainty exists about performance of different screening methods with regard to benefits, harms, and costs (especially on programmatic basis)Uptake of screening remains disappointingly lowIndividuals

20、 differ in their preferences for one test or another Primary care physicians differ in their ability to offer, explain, or refer patients to all options equallyAccess is uneven geographically, and in terms of test charges and insurance coverage第二十五頁，共二十七頁。25If tests that can prevent CRC are preferred, why not recomme