Positive Fecal Immunochemical Test Research Articles

Is annual screening by fecal immunochemical test necessary after a recent colonoscopy?

The population-based colorectal cancer screening guidelines in Japan recommend an annual fecal immunochemical test (FIT). However, there is no consensus on the need for annual FIT screening for patients who recently performed a total colonoscopy (TCS). Therefore, we evaluated the repeated TCS results for patients with positive FIT after a recent TCS to assess the necessity of an annual FIT. We reviewed patients with positive FIT in opportunistic screening from April 2017 to March 2022. The patients were divided into two groups: those who had undergone TCS within the previous 5 years (previous TCS group) and those who had not (non-previous TCS group). We compared the detection rates of advanced neoplasia and colorectal cancer between the two groups. Of 671 patients, 151 had received TCS within 5 years and 520 had not. The detection rates of advanced neoplasia in the previous TCS and non-previous TCS groups were 4.6% and 12.1%, respectively (p < 0.01), and the colorectal cancer detection rates were 0.7% and 1.5%, respectively (no significant difference). The adenoma detection rates were 33.8% in the previous TCS group and 40.0% in the non-previous TCS group (no significant difference). Only a few patients were diagnosed with advanced neoplasia among the patients with FIT positive after a recent TCS. For patients with adenomatous lesions on previous TCS, repeated TCS should be performed according to the surveillance program without an annual FIT. The need for an annual FIT for patients without adenomatous lesions on previous TCS should be prospectively assessed in the future.

Accuracy, Acceptability, and Application: Fecal Immunochemical Tests for Early Detection of Advanced Neoplasia in Colonoscopy-Based Surveillance.

The fecal immunochemical test (FIT) is widely used in colorectal cancer (CRC) screening, but limited data exist for its application in individuals at above-average risk for CRC who complete surveillance colonoscopies. To assess the accuracy, acceptability, and effectiveness of FIT in the interval between surveillance colonoscopies, for predicting advanced neoplasia (advanced adenoma or CRC) at the next colonoscopy. Individuals enrolled in an Australian surveillance program were included. Diagnostic accuracy was determined for 614 individuals completing a two-sample FIT (OC-Sensor) ≤ 3months preceding surveillance colonoscopy. 386 Individuals were surveyed to assess acceptability of interval FIT. Additionally, a retrospective analysis was performed on 7331 individuals offered interval FIT between colonoscopies, where a positive FIT (≥ 20µg hemoglobin/g feces) triggered an early colonoscopy. Associations between interval FIT results and advanced neoplasia were determined using regression analysis. FIT detected CRC and advanced adenoma with sensitivities of 60.0% (3/5) and 27.1% (35/129), respectively. Most (89.1%, 344/386) survey respondents preferred completing interval FIT every 1-2years. The detection rate of interval FIT for advanced neoplasia decreased with increasing FIT completion. Individuals returning a positive FIT had a higher risk of advanced neoplasia than those who did not complete FIT. Positive interval FIT reduced time-to-diagnosis for CRC and advanced adenoma by a median of 30 and 20months, respectively. Interval FIT was well accepted and enabled earlier detection of advanced neoplasia in individuals at above-average risk of CRC. Given that interval FIT predicts advanced neoplasia, it may be used to personalize surveillance colonoscopy intervals.

Association of Endoscopist Colonoscopy Quality Measures With Follow-Up Colonoscopy Outcomes After Positive Stool Tests (Multitarget Stool DNA or Fecal Immunochemical Test): Retrospective Cross-Sectional Analysis of Data From the New Hampshire Colonoscopy Registry.

Negative colonoscopies following positive stool tests could result from stool test characteristics or from the quality of endoscopist performance. We used New Hampshire Colonoscopy Registry data to examine the association between endoscopist detection rates and polyp yield in colonoscopies performed for positive fecal immunochemical test (FIT) or multitarget stool DNA (mt-sDNA) test to evaluate the degree to which positive stool tests followed by negative colonoscopy ("false positives") vary with endoscopist quality. In addition, we investigated the frequency of significant polyps in the subgroup of highest quality colonoscopies following positive stool tests. We compared the frequencies of negative colonoscopies and of specific polyps following positive stool tests across quartiles of endoscopist adenoma detection rate (ADR) and clinically significant serrated polyp detection rate (CSSDR). Our sample included 864 mt-sDNA+ and 497 FIT+ patients. We found a significantly lower frequency of negative colonoscopies following positive stool tests among endoscopists with higher ADR and CSSDR, particularly in the 2 highest quartiles. In addition, detection of any adenoma after a positive stool test for endoscopists in the fourth ADR quartile was 63.3% (FIT+) and 62.8% (mt-sDNA+). Among endoscopists in the fourth CSSDR quartile, sessile serrated lesions were found in 29.2% of examinations following a positive mt-sDNA and in 13.5% following FIT+ examinations. The frequency of negative colonoscopies after positive stool tests was significantly higher in examinations performed by endoscopists with low ADR and CSSDR. Our results also suggest a benchmark target of at least 40% for ADR in patients with mt-sDNA+ or FIT+ tests and 20% for sessile serrated lesions in mt-sDNA+ patients.

Adherence to follow-up and resource use after abnormal FIT-screening: Evaluation of the Danish colorectal cancer screening program.

Background and study aims The effectiveness of colorectal cancer screening programs depends on adherence to surveillance protocols for screening-positive individuals. We evaluated adherence in the Danish population-based screening program and estimated the volume of diagnostic resources required to achieve this adherence. Patients and methods In this register- and population-based study, we included individuals with a positive fecal immunochemical test (FIT) screening from 2014 to 2017 and followed them until mid-2022. All endoscopic, imaging, and surgical procedures performed at public and private hospitals were identified. Adherence to national protocols was reported in terms of proportions and timeliness. Use of diagnostic and surveillance procedures was estimated during a 4-year post-screening period. Results Among 82,221 individuals with a positive FIT test, 84% had a baseline colonoscopy within 1 month. After removal of intermediate or high-risk adenomas, 12% and 6%, respectively, did not have any follow-up. Only ~50% had timely surveillance. Approximately 10% to 20%, depending on their referral diagnosis, did not have a second surveillance colonoscopy. In addition, 12% with a negative colonoscopy had a second colonoscopy within 4 years. Conclusions High adherence to baseline colonoscopy after positive FIT-screening is followed by lower adherence throughout the adenoma surveillance program. Better adherence to the guidelines could potentially improve the effectiveness and efficiency of the screening program.

Paper Title: Colorectal cancer screening knowledge among community pharmacists: A national survey

Colorectal cancer (CRC) screening can reduce CRC morbidity and mortality. Community pharmacies could be a viable option for delivering home-based CRC screening tests such as fecal immunochemical tests (FITs). However, little is known about community pharmacists' knowledge about CRC screening guidelines. We assessed community pharmacists' knowledge about CRC screening to identify education and training needs for a pharmacy-based CRC screening program. Between September 2022 and January 2023, we conducted an online national survey of community pharmacists practicing in the United States (US) (Responders were eligible if they were currently-licensed community pharmacists and currently practiced in the US. The survey assessed knowledge of national CRC screening guidelines, including recommended starting age, frequency of screening, different screening modalities, and follow-up care. Using multiple linear regression, we evaluated correlates of community pharmacists' level of CRC screening knowledge, defined as the total number of knowledge questions answered correctly from "0" (no questions correct) to "5" (all questions correct). 578 eligible community pharmacists completed the survey, with a response rate of 59%. Most community pharmacists correctly answered the question about the next steps following a positive FIT (87%) and the question about where a FIT can be done (84%). A minority of community pharmacists responded correctly to questions about the age to start screening with FIT (34%) and how often a FIT should be repeated (28%). Only 5% of pharmacists answered all knowledge questions correctly. Community pharmacists answered more CRC screening knowledge questions correctly as their years in practice increased. Board-certified community pharmacists answered more CRC screening knowledge questions correctly compared to those who were not board-certified. To ensure the successful implementation of a pharmacy-based CRC screening program, community pharmacists need to be educated about CRC screening and trained to ensure comprehensive patient counseling and preventive service delivery.

Screening, awareness and challenges for colorectal cancer treatment in Saudi Arabia: an update

Colorectal cancer (CRC) is the second most common cancer in the world. In Saudi Arabia, CRC is the most common cancer in males and the third most common in females, and its incidence rate is rising as the country continues to develop. However, the country does not have a national CRC screening program for CRC. This review aims to review recent studies that have attempted to address and rectify this issue and discern the most notable and prevalent barriers. Despite these efforts, guidelines are still lacking. Two prospective studies have been conducted in recent years, one of which was a national pilot screening program conducted by the Ministry of Health (MOH). While both had a similar number of participants, the colonoscopy rate for patients with a positive fecal immunochemical test (FIT) in the MOH program was only 20% compared to 75.8% in the Al-Kharj program. Awareness of the Saudi population regarding CRC and its screening appears to be insufficient. The most common barriers to patients' willingness to undergo screening were embarrassment, fear, and pain. Barriers to physicians are mostly related to factors outside their hands, such as lack of equipment and time. We conclude that efforts should be made to establish a national screening program and improve awareness of the population and physicians.

Evaluation of the “Burgenland PREvention trial of colorectal cancer Disease with ImmunologiCal Testing” (B-PREDICT)—a population-based colorectal cancer screening program

BackgroundThe colorectal cancer (CRC) screening program B-PREDICT is a population based invited two stage screening project using a faecal immunochemical test (FIT) for initial screening followed by a colonoscopy for those with a positive FIT. B-PREDICT was compared with the opportunistic screening colonoscopy (OPP-COL), performed in course of the nationwide screening program.MethodsWithin B-PREDICT all residents of the Austrian federal state Burgenland, aged between 40 and 80 are annually invited to FIT testing. All individuals who underwent initial colonoscopy in Burgenland between 01/2003 and 12/2014, were included in this study. Individuals from the FIT-triggered invited screening program B-PREDICT were compared with those from the non-FIT triggered OPP-COL.Results15 133 individuals from B-PREDICT were compared to 10 045 individuals with OPP-COL. CRC detection rates were 1.34% (CI-95%, [1.15; 1.52]) in B-PREDICT compared to 0.54% in OPP-COL (95%-CI, [0.39; 0.68] p < 0.001). The decrease in the age standardized incidence rates of CRC was more pronounced in the population screened with FIT than in the general population screened with colonoscopy. Changes in incidence rates per year were -4.4% (95%-CI, [-5.1; -3.7]) vs. -1.8% (95%-CI, [-1.9; -1.6] p < 0.001).ConclusionsB-PREDICT shows a two-fold higher detection rate of CRC as well as HRA compared to OPP-COL.

Association between Endoscopist Volume and Interval Cancers after Colonoscopy: Results from the National Colorectal Cancer Screening Program in Korea.

The rate of interval colorectal cancer (iCRC) is now accepted as a key performance indicator of organized colorectal cancer (CRC) screening programs. We aimed to examine the association between endoscopist volumes and the rate of iCRC among individuals with a positive fecal immunochemical test (FIT) within a nationwide population-based CRC screening program. Individuals aged ≥50 years who underwent colonoscopy after a positive FIT from January 1, 2019 until December 31, 2020 in the Korean National Cancer Screening Program (KNCSP) were enrolled. We converted the data into per-endoscopist screening results, calculated the iCRC rates per endoscopist, and compared them to the previous year's annual volume that was divided into five groups (V1, 1-9; V2, 10-29; V3, 30-59; V4, 60-119; V5, ≥120). A total of 10,412 endoscopists performed 216,907 colonoscopies. Overall, the average rate of iCRC per endoscopist was 8.46 per 1,000 examinations. Compared with the group with the highest volume (V5 group), the rate of iCRC was 2.21 times higher in the V1 group. Similar trends were observed in the other groups (V2: Relative risks [RR], 2.15; 95% Confidence Interval [CI], 1.57-2.94; V3: RR, 1.56, 95% CI, 1.15-2.13; V4: RR, 1.18; 95% CI, 0.83-1.67). The findings emphasize that endoscopists with lower procedure volumes have higher risks of interval cancer being missed or undetected. To maximize the preventative impact of colonoscopy for colorectal cancer, this issue should be addressed by monitoring endoscopist volumes and variations in performances.

Feasibility of opportunistic colorectal cancer screening of hospitalized patients in tertiary care and community hospitals.

Population screening for colorectal cancer (CRC) remains low, requiring alternative approaches for increasing participation. Opportunistic screening of hospitalized patients may aid in increasing uptake rates. To assess whether inpatients can be recruited for opportunistic CRC screening using fecal immunochemical testing (FIT). Inpatient charts were prospectively reviewed for study eligibility on admission of patients to the medical wards of 3 hospitals in Winnipeg, Canada. Eligible patients were approached for participation and consent. Inoculated FIT specimen collection tubes were sent to the hospital laboratory for testing. Patients with positive FIT results received a follow-up colonoscopy. In total, 1542 inpatient charts were screened for eligibility; 53 patients were identified for enrollment (51.9% were male; median age, 59 years), of whom 13 patients consented to participate but only 7 provided a stool specimen. One of those 7 patients had a positive FIT result. The overall screening rate was low, at 0.45%. The primary reason for exclusion of patients was age (outside of the range of 50-75 years), followed by patients having recent gastrointestinal bleeding and/or known intestinal diseases. Our data suggest that it is infeasible to recruit inpatients for opportunistic CRC screening in routine clinical practice.

Risk of cancers proximal to the colon in fecal immunochemical test positive screenees in a colorectal cancer screening program

In more than half of the colorectal cancer (CRC) screening participants with a positive fecal immunochemical test (FIT) result, no advanced neoplasia (AN) is detected at colonoscopy. The positive FIT result could also be generated by cancers located proximal to the colon: upper gastrointestinal, oral cavity, nose and throat cancers. We evaluated screenees' risk of being diagnosed with a cancer proximal to the colon within the three years and compared risks between those with a positive versus those with a negative FIT. Data of Dutch CRC screening participants who underwent biennial FIT-based screening 2014-2018 were collected from the national screening database and linked to the National Cancer Registry. Screenees were classified into three groups: FIT-positives with AN (FIT+/AN+), FIT-positives without AN (FIT+/AN-) and FIT-negatives (FIT-). We compared the cumulative incidence of cancers proximal to the colon in each group three years after FIT. A Cox regression analysis with left truncation and right censoring, using FIT positivity as time-dependent variable and stratified for sex, was performed to compare the hazard of cancers proximal to the colon in FIT-positives versus FIT-negatives. Three-year cumulative incidence of cancers proximal to the colon in FIT+/AN+ (n=65,767), FIT+/AN- (n=50,661) and FIT- (n=1,831,647) screenees was 0.7%, 0.6% and 0.4%, respectively (p<0.001). FIT-positives were older and more frequently male than FIT-negatives (p<0.001). Significantly more cancers proximal to the colon were detected among FIT-positives (p<0.001; hazard ratio 1.55, 95% CI: 1.44 to 1.67). FIT-positive screenees were at significantly increased risk of being diagnosed with a cancer proximal to the colon within three years after FIT, though the three-year cumulative incidence was still less than one percent.

Insights Into Colorectal Cancer Screening: A Multidatabase Cohort Study of Over 1.5 Million Taiwanese

IntroductionColorectal cancer (CRC) remains a significant public health concern. This study aims to provide a comprehensive understanding of the effectiveness of fecal immunochemical test (FIT) screening on CRC incidence and mortality, leveraging the scale of over 1.5 million randomly selected Taiwanese participants and more than 11.7 million person-years of follow-up. MethodsThis prospective cohort study merges data from three robust Taiwanese health databases: the CRC screening program, cancer registration, and death registration databases. Incidence and mortality rates of CRC were calculated based on age, sex, urbanization, and past screening status. Cox proportional hazard models were used to assess the association between screening statuses and CRC incidence or mortality, adjusting for age, sex, and urbanization levels. Statistical analysis of the data was conducted in 2021-2022. ResultsFIT screening was associated with a 33% reduction in CRC incidence and a 47% reduction in mortality. The study identified a dose-response relationship between the fecal hemoglobin concentration (f-HbC) levels and CRC risk. Participants with consistent FIT-negative results had significantly reduced CRC incidence and mortality risks, while those with one or more positive FIT results faced increased risks. Notably, compliance with follow-up examinations after a positive FIT significantly lowered mortality risk. ConclusionsThis large-scale study validates the efficacy of FIT screening in reducing CRC incidence and mortality. It offers a nuanced understanding of how various screening statuses impact CRC risks, thus providing valuable insights for public health strategies aimed at CRC prevention.

Qualitative Fecal Immunochemical Test as a Screening Test for Colorectal Cancer

Colorectal cancer is one of the most common cancers, causing mortality, morbidity, and economic burden. Patient survival differs due to differences in access to health facilities, as well as diagnostic and therapeutic modalities. Early detection can allow colorectal cancer to be diagnosed at an earlier stage, improving patient outcomes and lowering mortality. Due to the lack of a national screening program in Indonesia, as well as the uneven availability of colonoscopy tools, the fecal immunochemical test has become the preferred screening method. This cross-sectional study aims to validate the application of the fecal immunochemical test for colorectal cancer detection. Fecal immunochemical test examination is performed on all patients with suspected colorectal cancer who will undergo a colonoscopy examination at Prof. Hospital dr. I.G.N.G. Ngoerah, Bali, Indonesia. Histopathological examination is used to diagnose colorectal cancer. This study included 78 people with a colorectal cancer prevalence of 40.91%. There were 38(57.6%) subjects with positive fecal immunochemical test results in this study, and 25(65.6%) of them were diagnosed with colorectal cancer. The sensitivity, specificity, positive predictive value, and negative predictive value of the qualitative fecal immunochemical test in detecting colorectal cancer were 92.59%, 66.67%, 65.79%, and 92.86%, respectively. The qualitative fecal immunochemical test has high sensitivity and can be used as an objective and accurate method of screening symptomatic patients with suspected CRC for colonoscopy.

Identifying the best cutoff value of the fecal occult blood immunochemical test in the detection of advanced and neoplastic colorectal lesions.

Screening is an effective tool for detecting colorectal lesions in asymptomatic subjects. There is a positive correlation between fecal immunochemical test (FIT) values and the size of tumors. Despite the efficacy of screening, the detection of colorectal cancer (CRC) remains low. The primary objective was to evaluate the best FIT cutoff value for detecting advanced adenomas and CRC among individuals at average risk in a country with a high incidence and morbidity from CRC. This observational and prospective study analyzed consecutive cases in 1461 asymptomatic subjects with a positive FIT (≥ 100 ng hemoglobin [Hb]/mL) referred for colonoscopy (2012-2015) at a tertiary center in Uruguay. Colorectal lesions were detected in 35.3% (516/1461) of cases, with a mean age of 62.8 ± 8.3 years. About 53.2% were men and 65.1% of the tumors were located in the left side of the colon. The size of the lesion and FIT values (p = 0.001) were positively correlated. Laterally spreading tumors predominated in the right colon (586 ng Hb/mL; 95% Confidence interval [CI] 443.4-760). One hundred and thirty-five (26%) lesions were advanced adenomas (15 ± 6.7 mm); 694.6 ng/mL; 95% CI 632.4-756.9). The highest diagnostic yield (0.5112) for advanced adenomas was at a FIT level of 400 ng Hb/mL (accuracy 88.6%). There were significant differences in FIT values early and advanced CRC (927 ng/mL; [95% CI: 637-1082] vs. 1453 [95% CI: 1352-1594; p = 0.001]). A FIT value of 400 ng Hb/mL was the best diagnostic yield to detect advanced adenomas and CRC. This value is useful during the COVID-19 pandemic as it allows prioritization of colonoscopy to those most at risk of significant disease, thus reducing risks to both patients and healthcare workers.

O228: Do additional faecal immunochemical tests (FIT) provide more reassurance that colorectal cancer is not being missed? Results from the repeat FIT (RFIT) study

Abstract Introduction Faecal immunochemical testing (FIT) is highly sensitive for colorectal cancer (CRC) detection. NICE recommend a single FIT in primary care for urgent cancer referrals. Little evidence regarding the benefit of repeating FIT exists. The repeat FIT (RFIT) study aims to determine whether second and third FIT provide reassurance and improve CRC or significant bowel disease (SBD) identification. Methodology Prospective observational cohort study (UK HRA and REC approval). Patients recruited from urgent referrals returned three FIT and underwent colonoscopy. χ2 test compared categorical data. Accuracy (sensitivity/specificity/PPV/NPV) reported for one, two and three FIT (95% CI). Three negative FIT (&amp;lt;10µg Hb/g) cohorts (single, double, triple) were compared with positive cohorts (one or more FIT ≥10µg Hb/g). SBD and CRC detection rates were compared by strategy. Median FIT was calculated for pathology. Results 460 patients included (mean age=66.8yrs, M:F 233:227, CRC=23, SBD=80). For single, double and triple negative FIT, CRC sensitivity remained static (95.7%), specificity (44.6%,40.7%,38.4%) and NPV decreased (99.5%,99.4%,99.4%). For SBD, sensitivity increased (78.8%,83.8%,86.3%), specificity decreased (47.4%,43.7%,41.6%) and NPV increased (91.4%,92.7%,93.5%). In single, double and triple positive FIT cohorts, CRC detection was 8.3%,16.1%, 20.9%. CRC mean FIT was 150µg Hb/g, &amp;lt;6 for benign pathology. Conclusion The presence of negative FIT (single/multiple) reduces likelihood of CRC/SBD. Multiple FIT strategy provides greater differentiation and improved CRC/SBD detection compared to single FIT. Repeat FIT offers a safe, cost-effective strategy for triaging symptomatic patients. This may provide reassurance, or safely allow investigation on non-urgent pathways.

Association between time to colonoscopy after positive fecal testing and colorectal cancer outcomes in Alberta, Canada.

To quantify the associations between time to colonoscopy after a positive fecal immunochemical test (FIT+) and colorectal cancer (CRC)-related outcomes in the context of a provincial, population-based CRC screening program. Population-based, retrospective cohort study in Alberta, Canada, including Albertans aged 50-74 with at least one FIT+ in 2014-2017. Study outcomes were CRC diagnosis after a FIT+ and a diagnostic follow-up colonoscopy in 2014-2019 and CRC stage at diagnosis. Multivariable logistic regression models were used to evaluate the relative risk of any CRC or advanced-stage CRC. Results were presented as crude odds ratio (OR) and adjusted OR (aOR) with 95% confidence intervals (CIs). Of the 787,967 participants who had a FIT, 63,232 (8%) had a FIT+ and met the study's eligibility criteria. The risk of any CRC or advanced-stage CRC stayed high and was relatively consistent for follow-up colonoscopies performed within 1-12 months of the FIT+. After 12 months, the risk of CRC was considerably higher, particularly for advanced-stage CRC. The OR and aOR for any CRC were 1.40 (95% CI: 1.13-1.73; p < 0.05) and 1.20 (95% CI: 0.96-1.49), respectively, and the OR and aOR for advanced-stage CRC were 1.42 (95% CI: 0.98-2.08) and 0.88 (95% CI: 0.59-1.32), respectively, for colonoscopy follow-up within 12-18 months versus 1-2 months. For Albertans who used FIT for CRC screening, a longer time interval between a FIT+ and follow-up colonoscopy, particularly over 12 months, increases the risk of having CRC and decreases the effectiveness of CRC screening programs.

The effect of antiplatelet therapy and oral anticoagulants on the accuracy of faecal immunochemical testing.

Faecal immunochemical testing (FIT) has been adopted to identify patients requiring further investigations on the colorectal cancer (CRC) referral pathway. We aimed to investigate the effect of antiplatelet and anticoagulant drugs on the accuracy of FIT results. This observational study categorised patients with suspected CRC symptoms, who completed both FIT and colonic investigations, into two groups (control and exposed) based on their use of antiplatelet and anticoagulant drugs. Two-by-two tables and receiver operating characteristic (ROC) curve analysis were used to determine accuracy. A total of 928 patients were divided into a control (n=683) and an exposed group (n=245). A nonsignificant higher proportion of patients tested positive in the exposed group (24.1% vs 18.4%, p=0.063). For detection of CRC, improved sensitivity of 87% vs 81.2%, specificity of 84.8% vs 79.9% and negative predictive value of 99.2% vs 98.3% was calculated in the control vs exposed groups, respectively. The positive predictive value was comparable between the two groups (21.4% vs 22% in the control and exposed groups, respectively). In ROC analysis, there was no difference between the groups (AUC 90% vs 87%, p=0.56). The use of antiplatelet and anticoagulant drugs did not increase the risk of positive FIT results on multivariate logistic regression analysis. FIT accuracy for CRC detection remained unaffected despite more patients testing positive in the exposed group. FIT should be considered a supplementary tool for triage. Antiplatelet and anticoagulant drugs do not need to be discontinued before collection of FIT.

Proportions and characteristics of interval cancer in annual fecal immunochemical test screening and postcolonoscopy colorectal cancer: Results from a Japanese multicenter prospective study using questionnaires, the C-DETECT study.

There are several types of colorectal cancer (CRC) according to the detection methods and intervals, including interval CRC (iCRC) and postcolonoscopy CRC (PCCRC). We aimed to examine their proportions and characteristics. We conducted a multicenter prospective study using questionnaires in Japan ("C-DETECT study"), in which differences in CRC characteristics according to detection methods and intervals were examined from consecutive adult patients. Because the annual fecal immunochemical test (FIT) was used in population-based screening, the annual FIT-iCRC was assessed. In total, 1241 CRC patients (1064 with invasive CRC) were included. Annual FIT-iCRC (a), 3-year PCCRC (b), and CRC detected within 1 year after a positive FIT with noncompliance to colonoscopy (c) accounted for 4.5%, 7.0%, and 3.9% of all CRCs, respectively, and for 3.9%, 5.4%, and 4.3% of invasive CRCs, respectively. The comparison among these (a, b, c) and other CRCs (d) demonstrated differences in the proportions of ≥T2 invasion ([a] 58.9%, [b] 44.8%, [c] 87.5%, [d] 73.0%), metastasis ([a] 33.9%, [b] 21.8%, [c] 54.2%, [d] 43.9%), right-sided CRC ([a] 42.9%, [b] 40.2%, [c] 18.8%, [d] 28.6%), and female sex ([a] 53.6%, [b] 49.4%, [c] 27.1%, [d] 41.6%). In metastatic CRC, (a) and (b) showed a higher proportions of BRAF mutations ([a] [b] 12.0%, [c] [d] 3.1%). Annual FIT-iCRC and 3-year PCCRC existed in nonnegligible proportions. They were characterized by higher proportions of right-sided tumors, female sex, and BRAF mutations. These findings suggest that annual FIT-iCRC and 3-year PCCRC may have biological features different from those of other CRCs.

Detection of Upper Gastrointestinal Disorders in Patients with Positive Fecal Immunochemical Test (FIT) and Normal Colonoscopy: A Cross-Sectional Study

Abstract Introduction Colorectal cancer (CRC) is the second most prevalent cancer in the world, and the fecal immunochemical test (FIT) can be mentioned among the CRC screening methods based on the detection of occult blood in the feces, which may indicate upper gastrointestinal (UGI) malignancies; therefore, patients with a positive FIT but normal colonoscopy may be considered for a UGI endoscopy. Materials and Methods The present study was conducted on patients with a positive FIT who were submitted to colonoscopy with normal results. They subsequently underwent endoscopy for the detection of UGI disorders. Results We included 121 patients (64.5% of women and 35.5% of men; average age: 58.85 ± 12.93 years), 72.7% of whom were positive for Helicobacter pylori. The predominant result of the UGI endoscopy was normal, followed by erythema of the gastric mucosa, and anemia and dyspepsia were the most common clinical findings. The most common pathological result was chronic gastritis, followed by acute gastritis. Only one patient presented stomach cancer (adenocarcinoma). Conclusion Considering the small prevalence of cancer in the UGI endoscopies of patients with positive FIT and normal colonoscopy, to the performance of UGI endoscopy in these patients may not be necessary.

Value of combined serum CEA, CA72-4, and CA19-9 marker detection in diagnosis of colorectal cancer.

The aim of this study was to examine whether the combination of serum tumor markers (carcinoembryonic antigen [CEA], carbohydrate antigen [CA]72-4, CA19-9) improves sensitivity and accuracy in the diagnosis of colorectal cancer and precancerous lesion tubular adenoma. An automatic electrochemiluminescence immunoassay with matched kits (ECLIA) was performed on a Roche Cobas e411 analyzer to determine the levels of serum CEA, CA72-4, and CA19-9 in 35 patients with early colorectal cancer, 87 patients with tubular adenoma, and 58healthy people undergoing colonoscopy after positive fecal immunochemical test (FIT) in a colorectal cancer screening program 2021 January to April. The values of these three tumor markers in the diagnosis of colorectal cancer and tubular adenoma were analyzed. 180 patients (92 female and 88 male) were included into the study. We compared serum CEA, CA72-4 and CA19-9 markers among 3 groups: healthy people (mean age 64,0 ±8,6), patients with tubular adenoma (mean age 62,7 ± 6,4) and colorectal cancer (mean age 59,2 ±6,2). The levels of serum CEA, CA72-4, and CA19-9 were higher in the colorectal cancer group than in the tubular adenoma group and healthy subjects, and these differences were significant (p < 0.05). The combination of CEA, CA72-4, and CA19-9had a higher diagnostic value for colorectal cancer compared to single markers, and the positive detection rate was 54.3%. The diagnostic power when using all three markers was the best, and applied for colorectal cancer and tubular adenoma. The combination of CA72-4, CEA, and CA19-9 markers increases the sensitivity and accuracy in the diagnosis of colorectal cancer and can thus be considered an important tool for early colorectal diagnosis.

A72 THE ENDOSCOPIC YIELD OF PRIORITIZED INDICATIONS USING A PROVINCIAL-WIDE COLONOSCOPY REFERRAL FORM

Abstract Background The widespread use of a standardized and validated province-wide colonoscopy referral form (PCRF), regrouping mutually exclusive indications into suggested priority wait time categories, has allowed for a more comprehensive assessment of routine colonoscopy practice Aims To validate the Quebec PCRF by better characterizing endoscopic finding yields according to specific clinical indications. Methods This retrospective cohort study includes consecutive adult patients with available data from the PCRF from two tertiary hospitals. The primary outcome was the diagnostic rates of colorectal cancer (CRC). Secondary outcomes assessed incidences of clinically significant lesions (CSL) on endoscopy and confirmed at pathology. These are CRC, advanced adenomas, sessile serrated polyps, polyps ≥ 5mm, colitis, colonic strictures, and miscellaneous other findings excluding hemorrhoids and diverticulosis. Descriptive and inferential statistics, and multivariable regression predictive modeling are reported. Results Overall, 14,657 patients (mean age 59.2 ± 14.0 years, 50.9% female) were included from September 2018 to August 2022. The most frequent indications for colonoscopy were polyp surveillance (IN13, 20.8%), recent change in bowel habits (IN7, 11.9%), a positive fecal immunochemical test (IN5, 8.3%), a family history of CRC or polyps (first-degree relative) (IN8, 6.4%), and suspected active inflammatory bowel disease (IBD) (IN3, 5.8%). Overall, 40.6% had CSL, including CRCs in 0.8%. CRCs were found more frequently for IN2 (19.7% vs 2.0%, pampersand:003C0.01), IN5 (29.9% vs 8.2%, pampersand:003C0.01), and an unexplained documented iron deficiency anemia (IN6) (11.8% vs 5.2%, pampersand:003C0.01). CSLs were more frequent for IN3 (1.6% vs 5.8%, p=0.04), IN7 (4.7% vs 12.0%, p=0.01), IN8 (0.8% vs 6.5%, p=0.01), IN13 (7.1% vs 20.9%, pampersand:003C0.01), IBD surveillance (IN15, 0.0% vs 4.0%, p=0.02), and surveillance for a significant family history (IN21, 0.0% vs 3.7%, p=0.02). On multivariable analysis, CRC was significantly associated with IN2 OR=31.8 (4.86; 208.7), IN5 OR=19.2 (3.86; 95.7), and IN6 OR=15.7 (2.37; 78.0) - (all are high priority PCRF referrals with a suggested shorter wait time than for most other indications). CSLs were significantly associated with age (OR=1.03 (1.02; 1.03)), IN2 (OR=2.32 (1.35; 3.99)), IN5 (OR=2.37 (1.74; 3.22)), and IN13 (OR= 1.66 (1.36; 2.02)). Conclusions This large cohort study confirms the validity of indications and corresponding prioritization of wait times of a PCRF. Funding Agencies CPAC and MSSS