Effect-of-radiotherapy-on-sexual-function--Med-Files：对性功能影响放射医学档案课件.ppt

1、Epidemiology3rd most common cancer in males and femalesAccounts for 11%of cancer deaths.In 2000,130,200 cases(colon and rectum).Lifetime risk 6%.EpidemiologyRare before the age of 40y,rapid increase at 50y.At presentation 37%localized,37%regional,20%metastatic.1 and 5y survival is 80%and 61%overall.

2、IBD,FAP,HNPCC,are at inc riskascending colon 11%transverse colon 4%descending colon 9%sigmoid colon and rectum 76%World 50-60%25-30%Poland5year survivalRisk FactorsPolyps-Most cancers arise from them.Classified as neoplastic(adenomatous)which are benign or malignant,and nonneoplastic(hyperplastic,mu

3、cosal,inflammatory,hamartomaous).Adenomatous polyps found in 33%of people by age 50,50%by age 70.Most lesions 2cm,34%in severe dysplasia).TreatmentEndoscopic removal,surveillance every three years.Biopsy if it cant be removed.Surgery for those not amenable to safe polypectomy(large sessile villous l

4、esions).TreatmentFungation,ulceration,distortion are contraindications for polypectomy.Colectomy indicated for residual carcinoma,those at high risk for+LN despite complete polypectomy.+margin,poor diff,level 4,vascular,lymphatic invasion.Sessile polyp with invasive cancer should be considered for r

5、esection even if no high risk pathologic features.Weigh all against pts medical condition of course.Hereditary Polyposis SyndromesAll have this in common:Multiple intestinal polyps,extraintestinal manifestations.FAP:1-2%of colon cancer patients.A point mutation of APC gene on chromosome 5,band q21.P

6、olyps found throughout the GI tract but most in colon.Symptoms manifest by ages 16-50.Cancer will develop in all by age 50.Hereditary Polyposis SyndromesGardners Syndrome:Variant of FAP.Colonic and extracolonic manifestations.Periampulary lesions,duodenal lesions,gastric polyps.Ocular,cutaneous,skel

7、etal(retinal,mandible,jaw,teeth,sebaceous cysts).Desmoids,hepatoblastoma,thyroid cancer,Turcots syndrome(brain).Hereditary Nonpolyposis SyndromesLynch I and II.Occurs five times more frequently than familial polyposis.1-5%of colon cancers.Lynch I just colon,Lynch II also involves endometrium,ovary,s

8、tomach,small bowel,biliary,pancreas,ureter,renal pelvis.85%lifetime risk of colon cancer,more right sided cancers(60-70%),earlier(45y),lower stage,better survival,but 20%risk of metachronous,synchronous lesions.Inflammatory Bowel DiseaseUlcerative colitis carries a risk of colorectal carcinoma 30 ti

9、mes greater than general population.Risk increases with duration of disease.After 30 years,risk increases to 35%Crohns disease associated with 10-20 fold increased risk of cancer.Need to do surveillance in these population.Previous Colon CancerA second primary colon cancer is three times more likely

10、 to develop in patients with a history of colon cancer.Metachronous lesions develop in 5-8%of patients.History of First-Degree RelativesPeople with first-degree relatives with colorectal cancer have a 1.8-8 fold increase risk of colorectal cancer.Risk is higher if more than one relative affected.Ris

11、k is higher if developed in the relative at a young age.Pathology90%adenocarcinomas.Four morphologic variants.Ulcerative(most common),exophytic(polypoid,fungating),annular(classic applecore),submucosal infiltrative(linnitus type).Grading system 1-3.Most developed to least differentiated glandular st

12、ructures.The Layers of the WallColon WallStagingA-to submucosa onlyB1-to muscularis only B2-thru wall,not adjacent.B3-Adjacent organs involved.C1-B1 plus LNC2-B2 plus LNC3-B3 plus LND-Distant metsA -95-100%B -72-80%C -26-34%D -0-2%Staging-TNMT1 invades submucosaT2 invades muscularisT3 invades subser

13、osaT4 invades organs outsideN1-1-3 nodesN2-4 or more nodesN3-central nodesM0-no mets M1-distant metsClinical PresentationBleeding,pain,bowel habit changes,weight loss,anorexia,nausea,vomiting,fatigue,anemia.Right upper quadrant pain,fevers sweats,hepatomegaly,ascites,effusions,adenopathy(METS).Obstr

14、uction(5-15%)increases risk of death 1.4 fold.Perforation(6-8%)increases it 3.4 fold.Stage I 15%,Stage II 30%,Stage III 20%,Stage IV 25%.Obstruction less common on right side.Liver MetsColon CancerDiagnosisScope,Chest X-ray,Complete blood count,CEA,Localized Fibrous TumorsPreop CT scan?Some get it f

15、or abnormal LFTs only(but only 15%of liver mets have abnormal LFTs).Others will get it if large bulky tumors to see about adjacent organs,LN.10%of mets are missed with preoperative and operative evaluations,IOUS best for this.Diagnosis15-20%liver mets not palpable.Preop CEA reflects prognosis,diseas

16、e extent(over 10-20 poor)CEA may not be elevated in poorly differentiated or rectal cancers.CEA really only good for follow up.Rectal CancerIn addition to History&Physical,CXR,CBC,LFTs,EUS,Proctoscopic exam,full colonoscopy,CT scan should be done for rectal cancer.Accurate preoperative staging criti

17、cal because stage may influence treatment decisions such as trans anal excision,preop chemoradiation.Rectal CancerEUS is most accurate tool in determining tumor stage with all layers identified with 67-93%accuracy.Differentiating T1 from T3 easy but T2 from T3 harder.Limitations of EUS:operator expe

18、rience,differentiating LN vs.blood vessels,post radiation changes,stenotic lesions,overstaging(10-15%),understaging(1-2%).Superior to CT or MRI for depth of tumor.Rectal CancerLymph node staging more difficult.EUS 62-83%accurate,CT scan 35-73%accurate.All these tests pick up size of LN only.50-75%of

19、 involved LN are normal in size,so may not be picked up.Similarly,enlarged LN may be inflammatory,so false negative.LN 3mm and hypoechoic are likely to have malignancy,also FNA might help under EUS guidance.Rectal CancerCT scanning of abdomen and pelvis is important for other organ involvement,and d

20、istant spread.CT is better than EUS for contiguous organ involvement.ScreeningFOBT,DCBE,endoscopy most useful screening methods.FOBT detects cancer at an earlier stage,with reduction in cancer deaths.Flexible sigmoidoscopy and polyp clearance has resulted in decreased colon cancer.Value of full colo

21、noscopy is noted since 40%of colon cancers occur proximal to splenic flexure.DCBE used if pt refuses scope,or poor scope,etc.Barium Enema Sigmoid CancerScreening CEA has no role in in screening for primary lesions.False positives occur in benign disease(lung,liver,bowel)as well as malignancies of pa

22、ncreas,breast ovaries,prostate,head and neck,bladder,kidney.CEA increased in smokers.60%of tumors will be missed by CEA alone.RecommendationsAge50 asymptomatic,average risk.FOBT yearly,scope if positiveFlex sigmoidoscopy every 5y(full colon if+)Increased risk:Same but start age 40.RecommendationsHx

23、of HNPCC:Full colon every 1-2y(20-30y)then full colon yearly after 40y.Hx Aden Polyps:repeat in 3y,second exam normal repeat 5y.Hx Colon cancer:Full colon within 1y,if second normal repeat 3y,if next normal every 5y.FAP:Counseling,Flex Sigmoid every 12 months.Cancer PreventionRemoval of pre-cancerou

24、s polyps prevent cancer(unique aspect of colon cancer screening)Improved SurvivalEarly detection markedly improves chances of long term survivalJust 40%of colorectal cancers are detected at the earliest stageA little more than half of Americans over age 50 report having had a recent colorectal cancer screening testSlow but steady improvement in these numbers over the past decade(but all are not benefiting to the same degree)