免疫法与化学法粪便潜血试验在结肠癌筛查中价值的荟萃分析

目的系统性评价免疫法粪便潜血试验(immunochemical fecal occult blood tests,iFOBT)与愈创木脂化学法粪便潜血试验(guaiac-based fecal occult blood tests,gFOBT)相比,是否能获得更高的筛检进展期结直肠肿瘤的临床应用价值。方法利用中英文检索词检索相关电子数据库,纳入直接比较iFOBT与gFOBT筛查结直肠肿瘤的随机临床试验,并提取其特征信息。根据QUADAS质量评价标准评价纳入文献的质量,荟萃分析各项研究中不同潜血试验方法对结直肠肿瘤的检出率和患者的依从性,计算相应的OR值和95%可信区间。通过漏斗图肉眼观察是否存在发表偏倚,并做Egger检验进一步验证。结果共5项随机临床试验(共22 709例)符合纳入标准。iFOBT与gFOBT对于结直肠癌及进展期腺瘤的检出率分别为2.23%和1.24%,合并OR值为1.50(95%CI:0.94~2.39)。而这种优越性主要体现在iFOBT与传统的化学法HemoccultⅡ相比时(OR=2.12,95%CI:1.66~2.71)。患者对于iFOBT和gFOBT的依从性分别为52.66%和43.93%,合并OR值为1.40(95%CI:1.16~1.68)。结论与传统gFOBT相比,iFOBT能够提高结直肠肿瘤筛检的准确性及患者的依从性。     

新疆沙湾地区大肠癌筛查研究的初步结果

目的探讨粪便隐血试验及结肠镜检查作为大肠癌筛查主要方式的临床价值。方法 2007～2009年对沙湾地区无症状及有下消化道症状自愿体检的患者,先行大便隐血试验阳性者进行结肠镜检查,对检查结果进行分析。结果≥40岁受检者共413例,粪便隐血试验阳性者69例,阳性率16.71%,共24例发现了58枚结肠息肉,包括腺瘤性息肉38枚,炎性息肉8枚,增生性息肉12枚;发现结肠癌13例,直肠癌5例,恶性淋巴瘤1例。〈40岁自愿体检者94例,粪便隐血试验阳性者6例,阳性率6.38%,3例患者发现了4枚结肠息肉,包括腺瘤性息肉1枚,炎性息肉2枚,增生性息肉1枚;发现直肠癌1例。结论对无症状自愿体检患者进行粪便及结肠镜检查能较早发现大肠息肉,对大便隐血试验阳性患者行全结肠镜检查更适合于对基层广大农牧民结直肠癌的筛查。     

某部大肠癌筛查中肠镜检查顺应性影响因素分析

目的 分析某部大肠癌筛查中肠镜检查顺应性的影响因素.方法 在某部大肠癌筛查中,对接受肠镜检查和拒绝肠镜检查的人群分别进行问卷调查,分析可能影响肠镜检查顺应性的因素.结果 收回有效问卷148份,高危人群中有42例接受肠镜检查,106例拒绝肠镜检查,调查人群的肠镜检查应答率为28.4％.单因素分析结果显示,年龄、周围人行肠镜检查、便潜血阳性、定期体检、没时间、怕疼痛、怕麻烦、认为没用与高危人群肠镜检查顺应性有关(P均＜0.05);Logistic回归分析显示,周围人行肠镜检查、便潜血阳性、定期体检、怕疼痛、认为没用是影响高危人群肠镜检查应答率的独立因素(P均＜0.05).结论 周围人行肠镜检查、便潜血阳性、定期体检的人群更容易接受肠镜检查,怕疼痛、认为没用是筛查人群拒绝接受肠镜检查的主要原因.     

免疫法粪便潜血试验在结直肠癌筛查中的价值

目的 探讨免疫法粪便潜血试验(IFOBT)在大系列健康体检人群中筛查结直肠癌及其癌前病变的临床价值.方法 对2006年7月至2007年6月间在上海交通大学医学院附属仁济医院行健康体检的5919例采用IFOBT筛查结直肠癌及其癌前病变,对阳性病例进行结直肠镜检查或x线钡剂灌肠检查,结合临床及病理资料进行分析.结果 5919例体检人群中IFOBT阳性者314例,阳性率为5.30%,其中241例(76.75%)接受了结直肠镜检查,23例(7.32%)接受了X线钡剂灌肠检查,总随访率达84.08%,失访50例.剔除失访病例后,共发现结直肠癌16例,检出率为2.73‰(16/5869),其中Dukes A期8例(50.00%),Dukes B期7例(43.75%),Dukes C期1例(6.25%),IFOBT阳性者中的结直肠癌检出率为6.06%(16/264).共发现结直肠腺瘤样息肉94例,检出率为16.01‰(94/5869),包括管状腺瘤55例(58.51%),绒毛状-管状腺瘤23例(24.47%),绒毛状腺瘤16例(17.02%),其中单发者55例(58.51%),多发者39例(41.49%);另见活动期溃疡性结肠炎6例.IFOBT阳性者中共检出116例结直肠癌或癌前病变,检出率为43.94%(116/264).结论 IFOBT适合于大系列人群结直肠癌及其癌前病变的筛查,能发现较早期结直肠癌和癌前病变,使疾病在可治愈阶段得到根治,从而有望减少结直肠癌的发病率和死亡率.     

粪便脱落细胞及其标志物检测筛查大肠癌的研究现状

近年来大肠癌发病率呈逐年上升趋势,早期大肠癌常无临床症状,需通过筛查才能发现。目前大肠癌筛查的常用方法是粪隐血试验,但它存在假阴性和假阳性过高的局限性。为了弥补其不足,人们尝试进行粪便脱落细胞及其相关标志物的检测以探讨大肠癌早期诊断的新方法,在大肠癌筛查上具有潜在的应用前景,本文对近年有关研究进展进行系统回顾。     

大肠癌肠镜检查结果与手术结果的比较

探讨大肠癌肠镜检查结果与手术治疗结果的关系。方法分析了１２５例大肠癌的临床资料、大肠镜检查结果及手术治疗情况。结果（１）直肠癌检出率最高,青年人大肠部哪病率在逐渐增高;（２）直肠癌肛诊阳性率为８５．０％,大肠镜诊断大肠癌的准确率为９９．２％     

大肠癌新型非侵入性筛查方法：分析肠道微生物

与临床危险因素评估和粪便潜血试验比较,肠道菌群的分析更能成功地区别癌前腺瘤性息肉和侵入性大肠癌。密歇根安娜堡大学Patrick D．Schloss博士表示：一个人的肠道微生物菌群是肠道所有细菌的集合。细菌在肠道中的数量是巨大的,细菌的多样性对我们的健康至关重要。通过测序16SrRNA基因的v4区域,能够鉴别存在于每个人肠道中的微生物。研究发现,肠道菌群的组成能够帮助我们识别区分癌前腺瘤性息肉和侵入性大肠癌。如果结果在更大的人群中得到证实,那么在粪便测试中加入肠道微生物分析,可以作为一种改进的,非侵入性的方式来筛选大肠癌。     

散发性大肠癌患者粪便APC基因突变的研究

本实验应用ＰＣＲ ＳＳＣＰ硝酸银染色技术检测了大肠癌患者肿瘤组织、粪便标本ＡＰＣ基因突变 ,旨在寻求新的大肠癌诊断标志物。材料与方法一、检测对象病例组 :大肠癌患者手术前粪便标本及手术中肿瘤组织标本。男 2 2例 ,女 19例 ,年龄 2 8～ 73岁 ,平均 5 2 .1岁。其中高分化腺癌 13例 ,中分化腺癌 17例 ,低分化腺癌 11例。Ｄｕｋｅｓ分期 :Ａ期 13例 ,Ｂ期 15例 ,Ｃ期 9例 ,Ｄ期 4例。对照组 :同一患者手术后粪便标本及手术中远离肿瘤组织的手术断端正常组织标本。二、实验方法(一 )粪便脱落细胞ＤＮＡ的提取 :参照文献 [1]并做改进。(…     

SPA免疫便潜血试验和直肠粘液T抗原试验互补普查大肠癌及其随访

本文联合采用人血红蛋白抗血清包被的含A蛋白葡萄球菌(SPA)进行免疫便潜血试验(SPA试验)和直肠粘液T抗原检测(T抗原试验)用于大肠癌普查初筛并对筛检人群进行随访。结果表明,在4843例无症状人群中,SPA和T抗原试验阳性者分别为472例(9.75％)和297例(6.13％).共769例阳性者行纤维结肠镜检查,检出大肠癌4例,腺瘤48例(>1.0cm者17例,占35.4％)。其中,SPA试验中仅3例癌,29例腺瘤阳性,T抗原试验中2例癌,27例腺瘤阳性,提示联合这两种初筛试验可提高大肠癌及其腺瘤的检出率。为验证普查后减少大肠肿瘤发生的效果,2年后对这些人群采用同样的普查方案随访,结果在受检的3641例人群中,共477例阳性者行纤维结肠镜检查,未发现大肠癌病例,腺瘤18例(>1.0cm者仅4例,占22.2％)。将两次检出的腺瘤进行不典型增生程度的比较,第二次检出的腺瘤轻度不典型增生病变占88.89％(16例),中重度不典型增生病变仅占11.11％(2例),而第一次检出腺瘤、中重度不典型增生病变占25％(12例)。上述结果表明利用这两种初筛试验进行互补性普查。可提高大肠癌及癌前病变的检出率,随访结果提示在无症状人群普查,不仅可使大肠癌及腺瘤的再检出率明显减少,且可使中重度不典型增生病变的发病机会明显减少。     

Gastric cancer after positive screening faecal occult blood testing and negative assessment

BACKGROUND: Gastric cancer may be suspected with otherwise unexplained positive faecal occult blood testing. AIMS: To assess the frequency of gastric cancer following positive faecal occult blood testing and negative colonoscopy. SUBJECTS: Age 40-74 cohort at first screening (1985-2001) with (a) faecal occult blood testing- (83,489), (b) faecal occult blood testing +/colonoscopy+ (2025), or faecal occult blood testing+/colonoscopy- (3555). METHODS: Gastric cancer incidence in faecal occult blood testing subsets, compared with expected standardized incidence rates. RESULTS: Gastric cancer risk was increased (standardized incidence rate=146.7; 95% confidence interval: 105.8-203.4) in faecal occult blood testing+/colonoscopy- subjects. A four-fold excess incidence occurred during first year (observed cases=10, standardized incidence rate=408.3; 95% confidence interval: 219.7-758.8), irrespective of faecal occult blood testing type (guaiac, immunological). No excess risk occurred in faecal occult blood testing- (observed cases=53, standardized incidence rate=91.2; 95% confidence interval: 84.1-98.8) or in faecal occult blood testing+/colonoscopy+ subjects (observed cases=2, standardized incidence rate=101.9; 95% confidence interval: 25.5-407.4). Assuming a 100% 3-year study sensitivity for gastric cancer, faecal occult blood testing positive predictive value would be 0.4% (40-74 years) or 0.7% (> or =60 years) in faecal occult blood testing+/colonoscopy- subjects. CONCLUSIONS: Data suggest an association of faecal occult blood testing+/colonoscopy- and excess gastric cancer incidence in the following year. Due to low faecal occult blood testing+ positive predictive value, routine upper digestive tract endoscopy in these subjects is questionable.     

Screening for colorectal cancer with immunochemical faecal occult blood tests

Population-based studies have shown that guaiac faecal occult blood testing followed by colonoscopy in case of positivity can reduce colorectal cancer mortality. However these tests have been criticised for their fairly low sensitivity. For this reason attention has been given to alternative tests. The aim of this paper is to review the evidence for screening for colorectal cancer using qualitative immunochemical faecal occult blood tests. For the complete range of tested cut-off values, immunochemical faecal occult blood tests lead to higher diagnostic yield, improved sensitivity and greater participation. The optimal number of samples and the optimal cut-off value has to suit local resources and the acceptability of missed cancers. All economic evaluations, despite some differences between studies, add further arguments to support the opinion that the immunochemical faecal occult blood test is currently the most cost-effective screening test for average-risk populations. These economic evaluations provide strong arguments in favour of the 1-sample strategy. With decreasing the cut-off value similar performances can be achieved with one-compared to two day sampling. Too few data are currently available to accurately compare existing qualitative tests.     

Screening for colorectal cancer in the UK

Colorectal cancer fulfils the World Health Organisation criteria for disease screening. It is now well established that screening for colorectal cancer is effective in reducing both incidence as well as mortality. Various modalities of screening methods with inherent strengths and weaknesses are available. Due to the emergence of innovative new techniques, the best way ahead is debatable. Evidence indicates that faecal occult blood testing and 'once only' flexible sigmoidoscopy appears to be the most suitable mode of mass screening for the UK population.     

Long-term effect of faecal occult blood screening on incidence and mortality from colorectal cancer

BackgroundSeveral randomized trials have shown a reduction of colorectal cancer mortality by screening using guaiac-based faecal occult blood tests. However, little is known on the long-term effect of screening at the population level in everyday practice.MethodsSmall-sized geographic areas including a total of 91,199 individuals were allocated to either biennal screening using the Hemoccult-II test or no screening. The expected mortality and incidence in the cohort invited to screening was determined using mortality and incidence in the non-screened population.ResultsColorectal cancer mortality was significantly lower in the population invited to screening than in the non-screened population after 11 screening rounds (standardized mortality ratio: 0.87; 0.80–0.94). The standardized mortality ratio remained significant whatever the duration of follow-up. This reduction in colorectal cancer mortality was more pronounced in those who participated in the first screening campaign, who were regular participants in screening rounds (standardized mortality ratio: 0.67; 0.59–0.76). In contrast, colorectal cancer incidence was not different between the screened and non-screened populations (standardized incidence ratio: 1.01; 0.96–1.06).ConclusionOur findings confirm, in the long term, that screening with Hemoccult can reduce colorectal cancer mortality. The data also highlight the benefit of regular participation in screening and the absence of effect of screening on colorectal cancer incidence.     

Endoscopic findings in the upper gastrointestinal tract of faecal occult blood-positive, colonoscopy-negative patients

BACKGROUND: Detection of faecal occult blood is recommended for colorectal cancer screening in average risk populations. However, many subjects do not have any cause found in the colon to account for the occult blood loss. AIMS: To determine the prevalence of upper gastrointestinal tract disease in faecal occult blood-positive, colonoscopy-negative patients. PATIENTS AND METHODS: Retrospective audit of 99 patients (56 females; mean age 60 years, range 18-83) who underwent same-day colonoscopy and upper gastrointestinal endoscopy over a 2-year period. RESULTS: Fifty-two of the 99 patients had a normal colonoscopy, 16 had diverticulosis and 2 had hyperplastic polyps; these 70 patients comprised the colonoscopy-negative group. Significant upper gastrointestinal tract disease was noted in 25 (36%) of the colonoscopy-negative group compared with 10 (34%) of the 29 colonoscopy-positive group (p=ns). Most of the upper gastrointestinal tract lesions identified were benign. Within the colonoscopy-negative group, patients with anaemia or upper gastrointestinal tract symptoms had a higher prevalence of positive findings in the upper gastrointestinal tract, but this association was not statistically significant. CONCLUSIONS: Endoscopic examination of the upper gastrointestinal tract in faecal occult blood-positive individuals reveals mostly benign disease, with an equal prevalence in colonoscopy-negative and colonoscopy-positive patients. Routine performance of upper gastrointestinal endoscopy in faecal occult blood-positive individuals is not indicated and should be undertaken only for appropriate symptoms.     

The impact of immunochemical faecal occult blood testing on colorectal cancer incidence

BackgroundThe efficacy of colorectal cancer screening based on faecal immunochemical test, in terms of reduction of colorectal cancer incidence, is under debate. In the district of Florence, an organized screening programme based on faecal immunochemical test has been running since the early 1990s. The aim of this study was to compare the risk of developing colorectal cancer for subjects undergoing faecal immunochemical test with those who did not undergo the test in the same period.MethodsTwo cohorts were analyzed: subjects who underwent an initial faecal immunochemical test between 1993 and 1999 (“attenders”), and unscreened residents in the same municipalities invited to perform the faecal immunochemical test in the same period (“non-attenders”). Kaplan–Meier and Cox regression analysis were performed to evaluate the risk of developing colorectal cancer.ResultsThe attenders’ and non-attenders’ cohorts included 6961 and 26,285 subjects, respectively. Cox analysis showed a reduction in colorectal cancer incidence of 22% in the attenders’ compared to the non-attenders’ cohort (hazard ratio = 0.78, 95% Confidence Interval: 0.65–0.93).ConclusionOur results support the hypothesis that screening based on a single faecal immunochemical test every 2 years produces a significant decrease in colorectal cancer incidence after an average follow-up observation period of 11 years.     

Switching from guaiac to immunochemical faecal occult blood test increases participation and diagnostic yield of colorectal cancer screening

BackgroundCompared with the guaiac-faecal occult blood test (gFOBT), faecal immunological tests (FIT) are considered to be more effective for colorectal cancer (CRC) screening. However, only scarce research has examined the outcomes of switching to FIT within a mature gFOBT-based CRC screening programme.MethodsWe reported a 15-year experience of biennial FOBT screening in a well-defined population of approximately one million inhabitants, including six gFOBT-based screening rounds and one round with FIT at the 30 μg Hb/g cut-off. The main outcome measures were screening participation, FOBT positivity and advanced neoplasia detection in each round.ResultsIn this study, 647 676 screenings were performed in 228 716 different individuals, leading to 17 819 positives and 16 580 follow-up colonoscopies. Compared with the last gFOBT round, switching to FIT led to an increased participation of nearly 20% points, and a fivefold increased detection of CRC and advanced adenoma among invitees (3-fold among attendees). The numbers needed to screen and scope to detect one advanced neoplasia declined from 221 to 66 and from 4.7 to 2.6, respectively.ConclusionsThe present population-based study demonstrated a dramatical increase in the diagnostic yield of advanced neoplasia by switching to FIT within a mature gFOBT-based CRC screening programme.     

"序贯粪隐血大肠肿瘤筛检方案"应用价值的再探讨

目的 通过自然人群大肠肿瘤普查了解近年北京市大肠癌发病情况，进一步探讨“序贯粪便隐血大肠癌筛检方案”的有效性和可行性。方法 选定15家医院医疗责任区内48100自然人群为本次普查靶人群。对其中30岁以上的社区或企业职工26827人进行普查登记，并连续进行3d序贯粪隐血检查。隐血阳性者接受结肠镜检查。符合高危条件者，全部接受隐血和肠镜检查。结果 预计普查人为26827人，实际普查人数为19852人，普查率为74％。男女比例为1．05：1。中位年龄50岁。序贯粪隐血阳性率为5．6％，检出大肠癌12例，其中DukesA期4例，B期7例，C期1例。Dukes A B共11例，占全部检出癌的91．66％。40岁以下人群未检出大肠癌，50岁以上人群中，检出大肠癌的比例随年龄升高而逐渐增加。高危人群中检出2例大肠癌，占该人群的0．28％，一般危险人群中检出10例大肠癌，占该人群的0．05％。结论 普查靶人群的大肠癌患病率为36．57／10^5，提示北京市城区有较高的患病率。采用“序贯粪隐血筛检方案”检出了91．66％的早期和较早期癌。提示该方案的有效性和可行性。高危人群和50岁以上的一般危险人群为大肠癌的重点普查对象。     

Narrow band imaging vs. high definition colonoscopy for detection of colorectal adenomas in patients with positive faecal occult blood test: A randomised trial

BackgroundThe impact of narrow band imaging in improving the adenoma detection rate in a screening scenario is still unclear.AimTo evaluate whether narrow band imaging compared with high definition white light colonoscopy can enhance the adenoma detection rate during screening colonoscopy.MethodsConsecutive patients presenting for screening colonoscopy were included into this study and were randomly assigned to the narrow band imaging group (Group 1) or standard colonoscopy group (Group 2). Primary end point was the adenoma detection rate and secondary aim was the detection rate of advanced adenomas.ResultsOverall, 117 patients were allocated to Group 1 and 120 to Group 2. Both the adenoma detection rate and the detection rate of advanced adenomas were not significantly different between the two groups (respectively, 52.1% vs. 55%, RR = 0.95, 95% CI 0.75–1.20; 32.5% vs. 44.2%, RR = 0.74, 95% CI 0.53–1.02). No significant difference between the proportions of polypoid and flat adenomas was found. Male gender, no prior history of screening, and endoscopist's adenoma detection rate were independent predictive factors of higher advanced adenoma detection rate.ConclusionsIn a screening scenario, narrow band imaging did not improve the adenoma nor advanced adenoma detection rates compared to high definition white light colonoscopy.     

Faecal calprotectin and faecal occult blood tests in the diagnosis of colorectal carcinoma and adenoma

BACKGROUND AND AIMS: Testing for faecal occult blood has become an accepted technique of non-invasive screening for colorectal neoplasia but lack of sensitivity remains a problem. The aim of this study was to compare the sensitivity and specificity of faecal calprotectin and faecal occult blood in patients with colorectal cancer and colonic polyps. METHODS: Faecal calprotectin and occult blood were assessed in 62 patients with colorectal carcinoma and 233 patients referred for colonoscopy. The range of normality for faecal calprotectin (0.5-10.5 mg/l) was determined from 96 healthy subjects. RESULTS: Median faecal calprotectin concentration in the 62 patients with colorectal carcinoma (101 mg/l, 95% confidence interval (CI) 57-133) differed significantly from normal (2.3 mg/l, 95% CI 1.6-5.0) with 90% of patients having elevated levels (normal <10 mg/l) whereas only 36/62 (58%) had positive faecal occult bloods. There was no significant difference in faecal calprotectin levels when considering location or Dukes' staging of tumour. Percentage positivity of faecal occult bloods was significantly higher for Dukes' stage C and D cancers compared with Dukes' A and B. In the colonoscopy group, 29 patients with adenomatous polyps were detected in whom the median faecal calprotectin was 12 mg/l (95% CI 2.9-32). Sensitivity for detection of adenomatous polyps was 55% using the calprotectin method and 10% using faecal occult blood testing. The overall sensitivity and specificity of calprotectin for colorectal cancer and adenomatous polyps as a combined group was 79% and 72%, respectively, compared with a sensitivity and specificity of faecal occult blood of 43% and 92%. CONCLUSIONS: Faecal calprotectin is a simple and sensitive non-invasive marker of colorectal cancer and adenomatous polyps. It is more sensitive than faecal occult blood tests for detection of colorectal neoplasia at the cost of a somewhat lower specificity.