2015—2018年广州市40～74岁社区人群试点结直肠癌筛查结果分析

[目的] 分析 40～74 岁不同年龄段人群结直肠癌筛查情况及肠镜检查结局，为调整结直肠癌筛查起始年龄提供科学依据和参考。 [方法] 收集、 整理 2015—2018 年广州市 40～74岁试点结直肠癌筛查数据，评价和比较 40～74 岁不同年龄段人群高危因素问卷调查(high-risk factor questionnaire,HRFQ)、粪便隐血试验(fecal occult blood test,FOBT)和全结肠镜检查的筛查效果。 [结果] 47 176 人参与了筛查，初筛阳性 10 608 人，初筛阳性率 22.49%;40～44 岁、45～49 岁、50～54 岁和 55～74 岁年龄组初筛阳性率分别为 21.91%(365/1 666)、20.87%(569/2 727)、20.80%(1 279/6 149)和 22.92%(8 395/36 634)，差异有 统 计学 意义 (P<0.001)，其中女性 55～74 岁年龄组初筛阳性率 22.58%(5 025/22 255)高于其他年龄组(P<0.001)。男、女性 FOBT 参与率高年龄组高于 40～4...     

粪便潜血试验和问卷调查在人群结直肠癌筛查中的应用评价

[目的]分析粪便潜血试验、危险因素数量化评估问卷调查在人群结直肠癌筛查中的应用价值。[方法]嘉善县2007年5月至2013年12月7个镇(街道)目标人群进行结直肠癌优化序贯筛查方案,即采用危险因素数量化评估问卷调查和粪便潜血试验作为初筛方案,完成结直肠癌筛查完成初筛117 130人,其中问卷调查116 153人,粪便潜血试验99 268人。通过初筛确定高危人群19 078人,最终有14 709人完成了结肠镜检查。[结果]在14 709人肠镜检查中,共检出结直肠癌148人,进展期腺瘤692人,非进展期腺瘤1590人。优化序贯筛查方案和粪便潜血试验对结直肠癌、进展期腺瘤和非进展期腺瘤的阳性预测值分别为1.01%、4.70%,10.81%和1.68%、6.22%和12.42%。问卷调查对结直肠癌、进展期腺瘤的阳性预测值明显低于优化序贯筛查方案,分别为0.50%、3.30%。如果筛查方案中去除慢性腹泻、慢性便秘、黏液便或血便史、不良生活事件史4个单项,对结直肠癌、进展期腺瘤、非进展期腺瘤的阳性预测值略有提高,能减少12.28%的肠镜检查量。[结论]我国现行的大肠癌优化序贯筛查方案对结直肠癌和进展期腺瘤有较高的阳性预测值,对非进展期腺瘤无明显效果,有进一步优化的必要和空间。     

广州市首轮结直肠癌筛查满意度调查

[目的]了解居民对广州市首轮结直肠癌筛查项目的满意情况。[方法]采用分层随机抽样方法,从广州市结直肠癌筛查登记系统抽取2015年1月至2017年12月参与筛查的居民,包括初筛阴性、初筛阳性未做肠镜、初筛阳性已做肠镜3类,以问卷形式开展调查。[结果]完成问卷调查591份。结果显示,居民对结直肠癌筛查项目总体满意率为93.40%,对初筛的满意率(94.42%)高于肠镜检查(88.93%),P<0.05。居民对社区卫生服务中心的满意率为95.77%,不满意原因主要包括未通知筛查结果(24.00%)及筛查时间较长(20.00%);对社区卫生服务中心医务人员的满意率为94.92%,不满意的原因主要是医务人员服务态度较差(46.67%);对肠镜检查的满意率为88.93%,不满意的主要原因包括检查时感觉不舒服/疼痛(29.73%),医生操作不熟练/技术水平低(10.81%)及查出息肉未予以切除(10.81%)。78.14%肠镜检查者选择在去定点医院,未去定点医院的主要原因包括定点医院较远/交通不方便(31.51%),医生没明确介绍定点医院(17.81%)以及认为定点医院的技术水平低(16.44%)。[结论]广州市居民对首轮结直肠癌筛查的总体满意度较高,后续筛查中,行政及技术部门应对不满意的环节采取针对性措施,包括改善社区筛查流程、推广无痛肠镜及优化定点医院选点等,为市民提供更优质的筛查服务。     

定量免疫粪便隐血试验联合危险度评估在社区结直肠癌筛查中的应用

目的 探讨定量免疫粪便隐血试验（fecal immunochemical testing,FIT）联合危险度评估在社区结直肠癌（colorectal cancer,CRC）筛查中的应用价值。方法 选择2022年9月至2022年12月在吴江区开展CRC筛查的人群为研究对象。评估结果为阳性的有613例;评估阳性的人群中有320例作为试验组（1次定性FIT+1次定量FIT）,293例作为对照组（2次定性FIT）。试验组中有59例接受了肠镜检查,对照组中有36例接受了肠镜检查。结果 试验组的初筛阳性率为25.93%（83例）,对照组的初筛阳性率为18.77%（55例）,差异有统计学意义（P=0.034）。试验组接受肠镜检查的人群中,病变（CRC或结直肠腺瘤）的检出率为83.05%（49例）,对照组接受肠镜检查的人群中,病变（CRC或结直肠腺瘤）的检出率为63.89%（23例）,差异有统计学意义（P=0.032）。受试者操作特征曲线（receiver operator characteristic curve,ROC曲线）分析显示,定量FIT筛查早期肠道病变的曲线下面积为0.842（P=0.00...     

2018—2019年浙江省兰溪市结直肠癌筛查不同方案筛查效果的比较

[目的]比较结肠镜、免疫粪便隐血检测法（fecal immunochemical test,FIT）、新型风险分级筛查方案在浙江省兰溪市人群中的筛查效果。[方法]收集2018年6月—2019年6月浙江省兰溪市50～74岁满足研究条件的居民基线资料,并将其按照1∶2∶2比例随机分配至结肠镜组、FIT组、新型风险分级筛查组。结肠镜组进行结肠镜检查;FIT组首先进行FIT检测,FIT阳性者接受结肠镜检查;新型风险分级筛查组根据风险评估结果开展筛查,其中被评估为高危者接受结肠镜筛查,而被评估为低危者接受FIT筛查。比较3组间的人群参与率、结直肠肿瘤检出率及每检出1例进展期肿瘤所需结肠镜数。[结果]兰溪市基线共招募2 700名受试者入组,纳入男性1 154名（43.4%）,50～59岁者1 225名（46.1%）。相比结肠镜组（60.0%）,FIT组（99.2%）和新型风险分级筛查组（92.0%）的人群参与率更高。相比结肠镜组（7.5%）,FIT组（3.4%）和新型风险分级筛查组（3.8%）的进展期肿瘤（结直肠癌+进展期腺瘤）检出率较低。结肠镜组、FIT组、新型风险分级筛查组每检出1例进展期肿瘤...     

定量粪便免疫化学试验筛查阈值对结直肠肿瘤早筛价值的影响

目的:分析定量粪便免疫化学试验（fecal immunochemistry test，FIT）筛查阈值对体检人群结直肠肿瘤早筛价值的影响。方法:以2017年07月至2021年06月在我院接受定量FIT检测并行肠镜检查的1 267例人群为研究对象，比较不同性质肿瘤的定量FIT数值和阳性率。通过Logistic 回归和受试者工作特征（receiver operating characteristic，ROC）曲线分析比较不同性别、年龄和不同阳性阈值下定量FIT对进展期肿瘤的筛检效能。结果:定量 FIT筛查阳性率为4.7%，阳性人群肠镜依从性为22.2%。结直肠癌患者的定量FIT数值高于进展期腺瘤和其他肠镜结果。当定量FIT水平为100~199 μg/L、200~299 μg/L、300~499 μg/L和500 μg/L以上时，患进展期肿瘤的风险分别是<100 μg/L时的4.296倍、4.121倍、6.506倍和10.474倍。不同阳性阈值下，FIT阳性组进展期肿瘤检出率均高于阴性组，且在男性和50~75岁人群中均有统计学差异。在100 μg/L时的比值比（odds ratio，OR）最大（总体OR=6.817，95%CI:2.727~17.040；男性OR=5.570，95%CI:2.198~14.115；50~75岁OR=10.178，95%CI:3.158~32.803）。此时，定量FIT对进展期肿瘤的灵敏度分别为94.7%、93.0%、96.2%，特异度分别为27.6%、29.6%、28.7%。当阳性阈值由100 μg/L升高至500 μg/L时，FIT诊断进展期肿瘤的灵敏度下降，特异度升高，但阳性预测值和阴性预测值变化不大。结论:定量FIT阳性阈值在100 μg/L时筛查进展期结直肠肿瘤的灵敏度较好，但特异度较低，是应用在体检人群伺机性筛查中较好的结直肠肿瘤早筛参考指标。     

广州市人群2015~2017年大肠癌筛查成本分析

摘 要：［目的］ 对广州市首轮大肠癌筛查项目（2015~2017年）进行成本分析。［方法］ 在广州市和12个区项目办进行筛查项目支出信息调查,收集组织管理及筛查直接成本。另选取1243名参与初筛和602名接受肠镜检查的人群分别进行大肠癌筛查非医疗费用调查,收集本轮筛查的间接成本。并分析不同筛查策略下检出成本的差异,并对初筛参与率和肠镜检查参与率进行敏感性分析。 ［结果］ 2015~2017年广州市大肠癌筛查项目成本为3124.7万元,其中直接成本为1422.1万元,占45.5%,间接成本为1702.6万元,占54.5%。本项目癌前病变和癌症单例检出成本分别为27 077元和78 708元。筛查策略不变,如果将初筛参与率和肠镜检查率分别提高到50%和75%,则估算得到单例大肠癌前病变和癌症的检出成本分别降低27.1%、32.0%和 40.9%、53.1%。如果改变筛查策略,1次免疫法粪便隐血检查（以下简称iFOBT）+肠镜检查的筛查策略高危人群、大肠腺瘤和癌前病变的单例检出成本最低; 2次iFOBT+肠镜检查的癌症和早期癌的单例检出成本最低。［结论］ 本轮广州市大肠癌筛查成本较高,按癌前病变和癌症检出数计算,成本最低的是2次iFOBT+肠镜筛查方案;如果提高初筛参与率和肠镜检查参与率,则成本可以明显降低,尤其是提高肠镜检查参与率对降低成本效果明显。     

重复实施结直肠癌筛查服务的效率分析

摘 要：［目的］ 了解重复开展结直肠癌筛查的成效。［方法］ 以2015—2017年上海市松江区参加结直肠癌筛查的居民为研究对象,比较不同筛查服务次数发现癌前病变和结直肠癌的情况。［结果］ 2015—2017年上海市松江区共完成结直肠癌筛查199 456人次,涉及居民137 715人,发现癌前期病变4147人,结直肠癌201人。34.16%的调查对象3年中参与了多次筛查。一次筛查完成初筛137 715人次,实施肠镜检查10 022人次,癌前病变初筛检出率为2070.94/10万,肠镜检出率为28.46%,结直肠癌初筛检出率为94.40/10万,肠镜检出率为1.30%;二次筛查完成初筛47 045人次,实施肠镜检查4142人次,癌前病变初筛检出率为2442.34/10万,肠镜检出率为27.74%,结直肠癌初筛检出率为108.41/10万,肠镜检出率为1.23%;三次筛查完成初筛14 696人次,实施肠镜检查2141人次,癌前病变初筛检出率为4191.62/10万,肠镜检出率为28.77%,结直肠癌初筛检出率为149.70/10万,肠镜检出率为1.03%。二次、三次筛查的癌前病变初筛检出率高于一次筛查,癌前病变及结直肠癌的肠镜检出率差异无统计学意义。 ［结论］ 3年内多次实施结直肠癌筛查的效率与一次筛查相近,应提高居民肠镜检查依从性,可对60岁以上男性居民提供多次筛查服务从而提高筛查效益。     

粪便隐血试验与SDC2基因甲基化检测在结直肠癌筛查中的效果评价

[目的]比较粪便SDC2基因甲基化检测与粪便隐血试验用于人群结直肠癌筛查效果,为今后开展结直肠癌筛查技术及方案优化提供科学依据。[方法]以海宁市结直肠癌早诊早治筛查为平台,于2021年5月采用整群抽样方法抽取海宁市袁花镇3 000名40～74岁人群为研究对象,将SDC2基因甲基化检测纳入现有筛查路径,初筛包括结直肠癌风险评估、粪便隐血试验和SDC2基因甲基化检测,其中任一项阳性动员电子结肠镜检查,以结肠镜+病理结果为金标准判定筛查结果。[结果]共有2 664名对象完成结直肠癌风险评估并按要求同时送检了两份大便样品,其中男性1 303名,女性1 361名。单项粪便SDC2基因甲基化阳性为232例(8.71%),阳性者中116例(50.00%)完成肠镜检查;单项粪便隐血试验阳性为243例(9.12%),阳性者中126例(51.85%)完成结肠镜检查;粪便隐血试验和SDC2基因甲基化检测双阳性51例(Kappa=0.077,P=0.614),双阳性者中28例(54.90%)完成结肠镜检查,三组差异无统计学意义(χ²=0.452, P=0.798)。在单阳性组中,粪便隐血...     

浙江省海宁市40~74岁目标人群结直肠癌早诊早治筛查结果分析

[目的]评价海宁市结直肠癌早诊早治筛查效果.[方法]根据《癌症早诊早治项目技术方案》,对40～74岁目标人群采用危险因素量化评估问卷调查和两次大便隐血试验(FOBT)进行初筛,在此基础上,确定结直肠癌高危人群,然后,用电子结肠镜作进一步精筛,对查出的肠道病变进行及时干预.[结果] 2007～2012年海宁市结直肠癌筛查目标人群为322 034人,完成病史问卷调查286 470例,顺应率为88.96％;其中病史阳性16 807例,阳性率为5.87％;两次大便隐血试验461 348份,其中阳性25 928份,阳性率为5.62％.经初筛确定高危人群40 103人需进一步作结肠镜精筛.完成结肠镜检查29 069例,顺应率为72.90％;共检出肠道病变(息肉、腺瘤、癌)7408例,检出率25.48％,其中进展期以上病变1570例.病史阳性占检出病例数的41.10％,FOBT阳性占58.90％,而在205例结直肠癌中FOBT阳性占了91.71％.[结论]结直肠癌筛查成效显著,使无症状的结直肠癌及癌前期病变患者能够实现“三早”,减轻家庭和社会疾病负担.     

沈阳市苏家屯地区大肠癌筛查结果分析

[目的]通过大肠癌早诊早治项目,分析沈阳市苏家屯地区居民大肠癌发病情况。[方法]对苏家屯地区40~74岁人群采用问卷调查和粪便潜血实验免疫金标法（FIT）相结合筛出高危人群,对高危人群进行全大肠镜检查。[结果]目标人群40 157人中接受初筛人数为16 893人,顺应率为42.07%。初筛出高危人群3139人,占筛查人数18.58%。进行肠镜检查1655人,顺应率为52.72%。检出进展期腺瘤、大肠癌及类癌共83例。早诊率为95.18%,治疗率为100%。苏家屯地区居民大肠癌检出率为37.35/10万。[结论]苏家屯地区大肠癌检出率略高于我国农村地区平均水平。大肠癌筛查方案适用于城郊地区开展,可提高大肠癌的早诊率,对提高治愈率及延长生存期有重要意义。     

上海市社区居民大肠癌筛查便隐血检测效果分析

背景与目的：上海市为符合条件的居民提供免费的大肠癌筛查服务,通过对上海市居民大肠癌筛查中两次便隐血检测和后续诊断检查结果的分析,评价筛查中两次便隐血检测的效果,为基于人群的疾病筛查项目提供科学依据。方法：筛查的目标人群为50~74岁的上海居民,使用两次免疫法便隐血检测和危险度评估为初筛,初筛阳性者进行肠镜检查。结果：筛查期间,共有809 528人完成了两次便隐血检测,便隐血检测阳性者共有104 953人,其中第一次阳性的人数为47 421人,阳性率为5.9%,第二次阳性的人数为36 462人,阳性率为4.5%,两次阳性的人数为21 070人,阳性率为2.6%。便隐血检测阳性的筛查对象中,有49 339人接受了肠镜检查,肠镜检查顺应性为47.0%。两次阳性的筛查对象的肠镜参与率明显高于单次阳性的筛查对象（P<0.001）。在所有筛查出的大肠癌和癌前期病变中,仅进行一次便隐血检测可以诊断出大肠癌1 200例,占79.5%;发现癌前期病变3 777例,占68.1%。进行第二次便隐血检测可以多诊断出大肠癌310例,占20.5%;发现癌前期病变1 767例,占31.9%。结论：相比于单次便隐血检测, 进行两次便隐血检测的初筛可以更有效地检测出阳性对象,两次便隐血检测可提高后续肠镜检查的参与率,所检出的大肠癌和癌前期病变数量也均有所提高且增量成本较低。因此建议在以人群为基础的大肠癌筛查中采用两次或更多次数的便隐血检测,以提高筛查效率。     

Superior diagnostic performance of faecal immunochemical tests for haemoglobin in a head-to-head comparison with guaiac based faecal occult blood test among 2235 participants of screening colonoscopy

There is increasing evidence that faecal immunochemical tests (FITs) for haemoglobin offer a number of advantages over traditional guaiac based faecal occult blood tests (gFOBTs). However, evidence on diagnostic performance from direct comparisons with colonoscopy findings in all participants in the average risk population is still sparse. We aimed for a head-to-head comparison of three quantitative FITs with a gFOBT among participants of the German screening colonoscopy programme. Pre-colonoscopy stool samples and colonoscopy reports were obtained from 2235 participants of screening colonoscopy in 2005–2009. To enhance comparability of diagnostic performance of the various tests, we assessed sensitivity, specificity, predictive values and likelihood ratios of FITs after adjusting the FIT cut-off haemoglobin (Hb) concentrations in such a way that FIT positivity rates equalled the positivity rate of the gFOBT. Colorectal cancer, advanced adenomas and other adenomas were found in 15 (0.7%), 207 (9.3%) and 398 (17.8%) participants. The gFOBT was positive in 111 (5.0%) participants, with sensitivities (specificities) for detecting colorectal cancer, any advanced neoplasm or any neoplasm of 33.3% (95.2%), 8.6% (95.4%) and 5.5% (95.2%). At the same positivity rate, all three FITs outperformed the gFOBT in all indicators. In particular, all sensitivities of FITs were approximately two to three times higher at increased levels of specificity. All differences were statistically significant, except for some of the performance indicators for colorectal cancer. In conclusion, FITs can detect much larger proportions of colorectal neoplasms even if their cut-offs are set to levels that ensure equally low positivity rates as gFOBT.     

Performance of a colorectal cancer screening protocol in an economically and medically underserved population

The performance of combining fecal immunochemical tests (FITs) and a high-risk factor questionnaire (HRFQ) in colorectal cancer (CRC) screening in economically and medically underserved populations is uncertain. This study investigated the performance of a CRC screening protocol of combining FITs and an HRFQ as primary screening methods in a rural Chinese population. A CRC mass screening was conducted using FITs and an HRFQ as the first and colonoscopy as the second stage of screening in Jiashan, 2007-2009. The target population was 31,963 residents in three communities. The compliance was 84.7% for HRFQ, 76.4% for FITs, and 78.7% for colonoscopy. The detected rates of cancer, adenoma, nonadenomatous polyps, and advanced neoplasm were 2.7%, 14.8%, 5.9%, and 8.9% by FITs, which were higher than those by HRFQ (0.5%, 9.2%, 4.8%, and 3.8%, respectively). There was no significant difference in detected rate for nonadenomatous polyps between FITs and HRFQ. A total of 41.2% adenomas, 53.2% nonadenomatous polyps, and 29.8% advanced neoplasms were detected by HRFQ but missed by FITs. Positive predictive value of the screening protocol of combining FITs and HRFQ for advanced neoplasm was 5.7%, which was higher than FITs alone. Men had a higher prevalence of advanced neoplasm than women. Results indicate that combining FITs and HRFQ as primary screening methods is an efficient CRC screening strategy in economically and medically underserved populations.     

Factors associated with false-positive fecal immunochemical tests in a large German colorectal cancer screening study

In recent years fecal immunochemical tests (FITs) have been offered as a primary screening test for colorectal cancer (CRC) in a growing number of countries. Our study aims to identify factors associated with apparently false-positive results of FITs. In this cross-sectional study within the German population-based screening colonoscopy program, participants were invited to provide a stool sample for FIT prior to colonoscopy. Four thousand six hundred and fifty six participants aged 50–79 years with no known history of CRC or inflammatory bowel disease (IBD) and no findings of neoplasms at screening colonoscopy were included in the current analyses. Main outcome measures were rates and factors associated with apparently false-positive FIT results. Apparently false-positive FIT results were found for 378 participants (8.1%). Male sex (OR = 1.30, 95%CI 1.03, 1.62), age ≥65 years (OR = 1.27, 95%CI 1.01, 1.59), a BMI ≥30 kg/m² (OR = 1.81, 95%CI 1.36, 2.40), current smoking (OR = 1.63, 95%CI 1.18, 2.25), use of aspirin (OR = 1.36, 95%CI 1.02, 1.82) and a new diagnosis of IBD (OR = 9.13, 95%CI 2.18, 38.19) or other non-neoplastic findings (OR = 1.86, 95%CI 1.37, 2.51) at screening colonoscopy were independently associated with significantly increased odds of a positive FIT. Although considered false positive in the context of CRC screening, the identified factors associated with apparently false-positive FIT results are known risk factors for and may point to conditions other than colorectal neoplasms that may be potential sources of gastrointestinal bleeding, potentially requiring further medical follow up.     

Making colonoscopy-based screening more efficient: A “gateopener” approach

Screening colonoscopy for early detection and prevention of colorectal cancer (CRC) is mostly used inefficiently. Here, we assessed the potential of an innovative approach to colonoscopy-based screening, by use of a single, low threshold fecal immunochemical test (FIT) as a “gateopener” for screening colonoscopy. Using COSIMO, a validated simulation model, we modeled scenarios including either direct invitation to screening colonoscopy or an alternative approach involving mailing a single (“gateopener”) FIT along with an invitation to colonoscopy contingent on a FIT value above a low threshold yielding a 50% positivity rate (ie, every other pretest will be positive). Under plausible assumptions on screening offer adherence, we found that such “gateopener screening” (use of screening colonoscopy contingent on a positive, low threshold gateopener FIT) approximately doubled cancer detection rates vs conventional screening. In those spared from screening colonoscopy due to a negative gateopener FIT pretest, numbers needed to screen were 10-times higher vs those for individuals with a positive FIT, peaking in >2000 and >3800 (hypothetically) needed colonoscopies to detect one case of cancer in men and women, respectively. Gateopener screening resulted in 42%-51% and 59%-65% more prevented CRC cases and deaths, respectively. In summary, by directing colonoscopy capacities to those most likely to benefit, offering screening colonoscopy contingent on a “gateopener” low-threshold FIT would substantially enhance efficiency of colonoscopy screening.     

Impact of adenoma detection on the benefit of faecal testing vs. colonoscopy for colorectal cancer

Colonoscopy quality, as measured by adenoma detection rates, varies widely across providers and is inversely related to patients' post‐colonoscopy cancer risk. This has unknown consequences for the benefits of faecal immunochemical testing (FIT) vs. primary colonoscopy screening for colorectal cancer. Using an established microsimulation model, we predicted the lifetime colorectal cancer incidence and mortality benefits of annual FIT vs. 10‐yearly colonoscopy screening at differing ADR levels (quintiles; averages 15.3–38.7%), with colonoscopy performance assumptions estimated from community‐based data on physician ADRs and patients' post‐colonoscopy risk of cancer. For patients receiving FIT screening with follow‐up colonoscopy by physicians from the highest ADR quintile, simulated lifetime cancer incidence and mortality were 28.8 and 5.4 per 1,000, respectively, vs. 20.6 and 4.4 for primary colonoscopy screening (risk ratios, RR = 1.40; 95% probability interval (PI), 1.19–1.71 for incidence, and RR = 1.22; 95%PI, 1.02–1.54 for mortality). With every 5% point ADR decrease, lifetime cancer incidence was predicted to increase on average 9.0% for FIT vs. 12.3% for colonoscopy, and mortality increased 9.9% vs. 13.3%. In ADR quintile 1, simulated mortality was lower for FIT than colonoscopy screening (10.1 vs. 11.8; RR = 0.85; 95%PI, 0.83–0.90), while incidences were more similar. This suggests that relative cancer incidence and mortality reductions for FIT vs. colonoscopy screening may differ by ADR, with fewer predicted deaths with colonoscopy screening in higher ADR settings and fewer deaths with annual FIT screening in lower ADR settings.     

The Optimal Cut-Off Level of The Fecal Immunochemical Test For Colorectal Cancer Screening in a Country with Limited Colonoscopy Resources: A Multi-Center Study from Thailand

Background: Selecting the cut-off point for the fecal immunochemical test (FIT) for colorectal cancer (CRC) screening programs is of prime importance. The balance between the test performance for detecting advanced neoplasia and the available colonoscopy resources should be considered. We aimed to identify the optimal cut-off of FIT for advanced neoplasia in order to minimize colonoscopy burden. Methods: We conducted a multi-center study in 6 hospitals from diverse regions of Thailand. Asymptomatic participants, aged 50-75 years, were tested with one-time quantitative FIT (OC-SENSOR, Eiken Chemical Co.,Ltd., Tokyo, Japan) and all participants underwent colonoscopy. We assessed test performance in detecting advanced neoplasia (advanced adenoma and CRC) and measured the burden of colonoscopy with different cut-offs [25 (FIT25), 50 (FIT50), 100 (FIT100), 150 (FIT150), and 200 (FIT200)ng/ml]. Results: Among 1,479 participants, advanced neoplasia and CRC were found in 137 (9.3%) and 14 (0.9%), respectively. From FIT25 to FIT200, the positivity rate decreased from 18% to 4.9%. For advanced neoplasia, an increased cut-off decreased sensitivity from 42.3% to 16.8% but increased specificity from 84.2% to 96.3%. The increased cut-off increased the positive predictive value (PPV) from 21.5% to 31.5%. However, all cut-off points provided a high negative predictive value (NPV) (>90%). For CRC, the miss rate for FIT25 to FIT 150 was the same (n=3, 21%), whereas that with FIT200 increased to 35% (n=5). Conclusions: In a country with limited-colonoscopy resources, using FIT150 may be preferred because it offers both high PPV and NPV for advanced neoplasia detection. It could also decrease colonoscopy workload, while maintaining a CRC miss rate similar to those with lower cut-offs.