Fecal Occult Blood Research Articles

Tumor-targeting engineered probiotic Escherichia coli Nissle 1917 inhibits colorectal tumorigenesis and modulates gut microbiota homeostasis in mice

AimsPreliminary studies have identified the use of probiotics as a potential treatment strategy against colorectal cancer (CRC). However, natural probiotics lack direct tumor-targeting and tumor-killing activity in the intestine. This study aimed to construct a tumor-targeting engineered probiotic to combat CRC. Main methodsStandard adhesion assay was performed to analyze the adherence ability of tumor-binding protein HlpA to CT26 cells. CCK-8 assay, Hoechst 33258 staining and flow cytometry analysis were used for examining cytotoxicity of tumoricidal protein azurin toward CT26 cells. An engineered probiotic Ep-AH harboring azurin and hlpA genes was developed using Escherichia coli Nissle 1917 (EcN) chassis. Antitumor effects of Ep-AH were evaluated in the azoxymethane (AOM) and dextran sodium sulfate salt (DSS)-induced CRC mice. Moreover, analysis of gut microbiota was conducted via fecal 16S rRNA gene sequencing and shotgun metagenomic sequencing. Key findingsAzurin caused a dose-dependent increase of apoptosis in CT26 cells. Ep-AH treatment reversed weight loss (p < 0.001), fecal occult blood (p < 0.01), and shortening of colon length (p < 0.001) than model group, as well as reducing tumorigenesis by 36 % (p < 0.001). Both Ep-H and Ep-A (EcN expressing HlpA or azurin) were less effective than Ep-AH. Furthermore, Ep-AH enriched the members of beneficial bacteria (e.g., Blautia and Bifidobacterium) and reversed abnormal changes of genes associated with several metabolic pathways (e.g., lipopolysaccharide biosynthesis). SignificanceThese results demonstrated that Ep-AH had excellent therapeutic benefits on cancer remission and gut microbiota modulation. Our study provides an effective strategy for anti-CRC treatment.

Fecal Occult Blood Screening before Cardiac Surgery.

Concerns of gastrointestinal (GI) bleeding after cardiac surgery are increasing with increased use of antiplatelets and anticoagulants. We investigated the roles of preoperative screening for fecal occult blood by fecal immunochemical test (FIT) widely used to detect GI bleeding and cancer. A retrospective review was done in 1,663 consecutive patients undergoing FIT before cardiac surgery between years 2012 and 2020. One or two rounds of FIT were performed 2 to 3 weeks before surgery, when antiplatelets and anticoagulants were not suspended yet. Positive FIT (> 30 μg of hemoglobin/g of feces) was observed in 227 patients (13.7%). Preoperative risk factors for positive FIT included age > 70 years, anticoagulants, and chronic kidney disease. Of those with positive FIT, 180 patients (79%) received preoperative endoscopy, including gastroscopy (n = 139), colonoscopy (n = 9), and both (n = 32), with no findings of bleeding. The most common finding of gastroscopy was atrophic gastritis (36%) while early gastric cancer was detected in 2 patients. The most common finding of colonoscopy was colon polyps (42%) while colorectal cancer was detected in 5 patients. Of 180 FIT-positive patients receiving endoscopy, 8 (4.4%) underwent preoperative GI treatment, while postoperative GI events were documented in 28 (15.6%). Of 1,436 with negative FIT, 21 (1.5%) presented GI complications after surgery. Preoperative FIT, which is influenced by anticoagulant use, has little impacts on identification of GI bleeding sites. However, it may be useful to detect GI malignant lesions, potentially impacting operative risks, surgical strategies, and postoperative management.

The connection between diverticulosis and colonic superficial neoplastic lesions in patients who underwent screening colonoscopy

PurposeIf could be a potential pathophysiological connection between colonic diverticula and colonic superficial neoplastic lesions, beyond the shared risk factors, has been a subject of debate in the last years. This study tries to evaluate the association between diverticulosis and colonic neoplastic lesions.MethodsThis is a cross-sectional study including asymptomatic patients who underwent a screening colonoscopy (patients with a positive fecal occult blood test under the regional program of colorectal cancer (CRC) screening), surveillance after polypectomy resection, or familiarity (first-degree relatives) between 2020 and 2021 to evaluate the association between diverticula and colonic polyps. A multivariate analysis with multiple logistic regression and odds ratio (OR) to study the independent association between adenomas and adenocarcinomas was performed.ResultsOne thousand five hundred one patients were included. A statistically significant association between adenomas or CRC alone and colonic diverticula was found (p = 0.045). On a multivariate analysis of demographic (age, gender) and clinical parameters (familiarity for diverticula and adenoma/CRC), only age was significantly associated with the development of colorectal adenomas or cancer (OR 1.05, 95% CI 1.03–1.07, p < 0.0001).ConclusionsThis study showed a statistically significant association between diverticula and colonic adenomas. However, it is impossible to establish a cause-effect relationship due to the intrinsic characteristics of this study design. A study with a prospective design including both patients with diverticulosis and without colonic diverticula aimed at establishing the incidence of adenoma and CRC could help to answer this relevant clinical question, since a potential association could indicate the need for closer endoscopic surveillance.

Colorectal Cancer Chemoprevention: A Dream Coming True?

Colorectal cancer (CRC) is one of the deadliest forms of cancer worldwide. CRC development occurs mainly through the adenoma-carcinoma sequence, which can last decades, giving the opportunity for primary prevention and early detection. CRC prevention involves different approaches, ranging from fecal occult blood testing and colonoscopy screening to chemoprevention. In this review, we discuss the main findings gathered in the field of CRC chemoprevention, focusing on different target populations and on various precancerous lesions that can be used as efficacy evaluation endpoints for chemoprevention. The ideal chemopreventive agent should be well tolerated and easy to administer, with low side effects. Moreover, it should be readily available at a low cost. These properties are crucial because these compounds are meant to be used for a long time in populations with different CRC risk profiles. Several agents have been investigated so far, some of which are currently used in clinical practice. However, further investigation is needed to devise a comprehensive and effective chemoprevention strategy for CRC.

Secondary Malignant Stomach Melanoma

Abstract Melanoma is a malignant tumor of melanocytes. In the gastrointestinal tract, most commonly occurs as a metastatic deposit, which is usually diagnosed at autopsy. We have described a 74- year-old woman with secondary deposits in the stomach. Manifested with nonspecific symptoms such as the palpatory painful tenderness of the epigastrium, anemia, high sedimentation and low serum iron. Fecal occult blood test was positive. Esophagogastroduodenal endoscopy was done and she was seen polypoid resizing of 60 x 30 mm with uneven edges. A pathological finding of biopsy shows existence malignant melanoma in the mucosa of the stomach.

Colorectal Cancer Diagnostic Methods: The Present and Future.

To meet the needs of the colorectal cancer (CRC) patient population, colorectal cancer screening is continuously updated. The most significant advice is to start CRC screening exams at age 45 for people at average risk for CRC. CRC testing is divided into two categories: stool-based tests and visual inspections. High-sensitivity guaiac-based fecal occult blood testing, fecal immunochemical testing, and multitarget stool DNA testing are stool-based assays. Colon capsule endoscopy and flexible sigmoidoscopy are visualization examinations. There have been arguments about the importance of these tests in detecting and managing precursor lesions because of the lack of validation of screening results. Recent advancements in artificial intelligence and genetics have prompted the creation of newer diagnostic tests, which require validation in diverse populations and cohorts. In this article, we have discussed the present and emerging diagnostic tests.

Colon Cancer Screening Methods: 2023 Update.

Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. National screening guidelines have been implemented to identify and remove precancerous polyps before they become cancer. Routine CRC screening is advised for people with average risk starting at age 45 because it is a common and preventable malignancy.Various screening modalities are currently in use, ranging from stool-based tests (fecal occult blood test (FOBT), fecal immunochemical test (FIT), and FIT-DNA test), radiologic tests (computed tomographic colonography (CTC), double contrast barium enema), and visual endoscopic examinations (flexible sigmoidoscopy (FS), colonoscopy, and colon capsule endoscopy (CCE)) with their varying sensitivity and specificity. Biomarkers also play a vital role in assessing the recurrence of CRC. This review offers a summary of the current screening options, including biomarkers available to detect CRC, highlighting the benefits and challenges encompassing each screening modality.

Colorectal cancer testing rates after implementation of an organised screening programme in Vaud, Switzerland

Canton Vaud, Switzerland, implemented an organised colorectal cancer screening programme with colonoscopy and faecal occult blood tests in 2015, 4 to 6 years ahead of neighbouring cantons. Before its implementation, nearly half of Swiss citizens were already up to date with screening, primarily from opportunistic colonoscopies. We hypothesised that earlier implementation of an organised programme would be associated with greater increases in colorectal cancer testing rates. We analysed Swiss health insurance claim data from CSS, a Swiss health insurer covering 16% of the Swiss population and 10% of canton Vaud. We stratified 50-69-year-olds into groups from Vaud, its four neighbouring cantons (Fribourg, Geneva, Neuchâtel and Valais), and the rest of Switzerland. We analysed overall, faecal occult blood test and colonoscopy testing rates for each year between 2010 and 2018. The overall testing rate increased from 7.6% in 2010 to 11.6% in 2018 (+4.0%) in Vaud, from 6.1% to 9.3% (+3.2%) in neighbouring cantons and from 7.4% to 8.6% (+1.2%) in the rest of Switzerland. The faecal occult blood test rate increased between 2016 and 2018 from 2.9% to 4.1% (+1.2%) in Vaud and from 1.7% to 2.6% (+0.9%) in neighbouring cantons, but it decreased from 3.1% to 1.5% (-1.6%) in the rest of Switzerland. The colonoscopy rate increased in all cantons, from 4.7% to 7.5% in Vaud (+2.8%), from 4.4% to 6.7% in neighbouring cantons (+2.3%) and from 4.3% to 7.1% in the rest of Switzerland (+2.8%). By 2018, 40% of faecal occult blood tests and 26% of colonoscopies in Vaud occurred in the organised programme. Those who completed an faecal occult blood test within the Vaud programme were younger, had fewer comorbidities and were more likely to have a high-deductible health plan than those tested outside the programme. Colorectal cancer testing rates increased between 2010 and 2018, with greater absolute increases in Vaud than in neighbouring cantons or the rest of Switzerland. Faecal occult blood test use increased in both Vaud and neighbouring cantons, possibly reflecting changes in testing patterns by general practitioners. By 2018, 40% of colonoscopies and 26% of faecal occult blood tests occurred within the screening programme.

Importance of the neutrophil-lymphocyte ratio and systemic immune-inflammation index in predicting colorectal pathologies in fecal occult blood-positive patients.

The fecal occult blood (FOB) test is one of the primary screening methods for colorectal cancer (CRC). In this study, we aimed to investigate the effect of the neutrophil/lymphocyte ratio (NLR) and systemic immune-inflammation index (SII) in predicting CRC and other colorectal pathologies in patients with a positive FOB test. This retrospective study included patients with a positive FOB test who underwent colonoscopy for the investigation of the etiology. The optimal cutoff levels of NLR and SII for predicting colorectal pathologies were determined using the receiver operating characteristic analysis. Of the 157 FOB+ patients, 35% were male and 65% were female, with a median age of 59 years. There were 96 patients in Group 1 and 61 patients in Group 2. The mean age of the patients in Group 2 was significantly higher (p < 0.001). The rate of male patients was significantly higher in Group 2. NLR and SII were significantly higher in Group 2 than in Group 1 (p < 0.001). The area under the curve values of NLR and SII in predicting colorectal pathologies in FOB+ patients were 0.817 and 0.825, respectively. At the cutoff values of 0.689 and 0.795, NLR and SII had a sensitivity of 60.66% and 95.83%, respectively, and a specificity of 95.83% and 100%, respectively. Neutrophil/lymphocyte ratio and SII can be used as important biomarkers in the early diagnosis of CRC and other colorectal lesions in patients with a positive FOB test.

Selenoprotein W Ameliorates Experimental Colitis and Promotes Intestinal Epithelial Repair.

Selenoprotein W (Selenow) is a ~9 kDa selenoprotein suggested to play a beneficial role in resolving inflammation. However, the underlying mechanisms are poorly understood. SELENOW expression in the human GI tract using ScRNAseq Gut Cell Atlas and Gene Expression Omnibus (GEO) databases revealed its expression in the small intestine and colonic epithelial, endothelial, mesenchymal, and stem cells and correlated with a protective effect in ulcerative colitis patients. Selenow KO mice treated with 4% dextran sodium sulfate (DSS) showed exacerbated acute colitis, with greater weight loss, shorter colons, and increased fecal occult blood compared to the WT counterparts. Selenow KO mice expressed higher colonic Tnfα, increased Tnfα+ macrophages in the colonic lamina propria, and exhibited loss in epithelial barrier integrity and decreased zonula occludens 1 (Zo-1) expression following DSS treatment. Expression of epithelial cellular adhesion marker (EpCam), yes-associated protein 1 (Yap1), and epidermal growth factor receptor (Egfr) were decreased along with CD24lo cycling epithelial cells in Selenow KO mice. Colonic lysates and organoids confirmed a crosstalk between Egfr and Yap1 that was regulated by Selenow. Overall, our findings suggest Selenow expression is key for efficient resolution of inflammation in experimental colitis that is mediated through the regulation of Egfr and Yap1.

Annual Report of the Korean Association of External Quality Assessment Service on Urinalysis and Fecal Occult Blood Testing (2021)

Annual Report of the Korean Association of External Quality Assessment Service on Urinalysis and Fecal Occult Blood Testing (2021)

Effects of Fecal Occult Blood Immunoassay Screening for Colorectal Cancer-Experience from a Hospital in Central Taiwan.

Background and Objectives: In 2004, the Health Administration of Taiwan began to promote a hospital-based cancer screening quality improvement program, under the principle that "prevention is better than therapy". The aim of this study was to evaluate the effectiveness of colorectal cancer (CRC) screening in patients who received a fecal immunochemical test (FIT) at a hospital in central Taiwan. Materials and Methods: This was a retrospective study. Results: Fecal occult blood immunoassays for CRC screening were conducted in 58,891 participants, of whom 6533 were positive (positive detection rate 11.10%). The positive patients then underwent colonoscopy, and the detection rates of polyps and CRC accounted for 53.6% and 2.4% of all colonoscopy-confirmed diagnoses (3607), respectively. We further enrolled data from patients diagnosed with CRC at our hospital from 2010 to 2018. The patients with CRC were divided into two groups according to whether or not they had received fecal occult blood screening. Among the 88 patients with CRC by screening, 54 had detailed medical records including cancer stage. Of these 54 patients, 1 (1.8%) had pre-stage, 11 (20.4%) had stage I, 24 (44.4%) had stage II, 10 (18.5%) had stage III, and 8 (14.8%) had stage IV CRC. The early cancer detection rates of the screening and non-screening groups were 66.7% and 52.7%, respectively, and the difference was significant (p = 0.00130). Conclusions: In this study, screening with FIT significantly increased the early detection of CRC. The main advantage of FIT is the non-invasiveness and low cost. It is hoped that the further adoption of early screening can increase the detection rates of colorectal polyps or early cancer to improve survival, reduce the high cost of subsequent cancer treatment, and reduce the burden on the patient and healthcare system.

Colorectal cancer screening: understanding the needs of the pre-screening group.

For the last three decades, although colorectal cancer incidence has been decreasing in those over 50 years of age, it has been increasing in those under 50 included in the pre-screening group (PSG). The present study aims to explain the screening-related factors and compliance of individuals in PSG who are not included in the colorectal cancer screening programme. This cross-sectional study was conducted with a total of 323 participants, 143 of whom were from the pre-screening group (40-49 years), and 180 from the screening included group (SIG) (50-70 years). Individuals included in PSG were more likely to have accepted that both faecal occult blood test (FOBT) (2.23 ± 1.22 vs. 1.89 ± 1.33, p = 0.018) and colonoscopy (2.37 ± 0.97 vs. 2.02 ± 1.14, p = 0.003) were useful and suitable screening tests in colorectal cancer. Adequate health literacy (OR = 4.3, 95% CI: 1.8-10.0, p = 0.001) and better education level (OR = 3.3, 95% CI: 1.3-8.4, p = 0.010) were factors of increased knowledge of colorectal cancer screening. The findings show that PSG has different characteristics than SIG and may be more fitting in the colorectal cancer screening programme if included.

Diagnostic Accuracy of Fecal Immunochemical Test (FIT) in Bleed-positive and Bleed-negative Colorectal Cancer (CRC) Among a Cohort of 5,090 Subjects who Participated in the Colorectal Neoplasia (CRN) Screening in Brazil.

This study assessed the diagnostic accuracy (DA) of fecal immunochemical test (FIT) ColonView (CV) and guaiac-based fecal occult blood test (HemoccultSENSA) among bleed-positive (history or signs of intestinal bleeding) and bleed-negative participants (no history or signs of intestinal bleeding) (n=5,090) in colorectal neoplasia (CRN) screening in Brazil. The eligible patients for the study (n=506) collected three consecutive stool samples, to be analyzed by both assays (CV, SENSA). Finally, 421/5090 (8.3%) patients returned both samples, which were subjected to final analysis. Receiver operating characteristic (ROC) analysis with different cut-offs was performed to assess the DA. The area under curve (AUC) values for i) visually analyzed (VA) CV for bleed-positive CRC, ii) automatically analyzed (AA) CV for bleed-positive CRC, iii) VA CV for bleed-negative CRC, and iv) AA CV for bleed-negative CRC as endpoints were as follows: i) AUC=0.864, ii) AUC=0.933, iii) AUC=0.836, and iv) AUC=0.892. In roccomp analysis, the differences in AUC values were: between i) and ii) p=0.068; between i) and iii) p=0.497; between i) and iv) p=0.488; between ii) and iii) p=0.0058; between ii) and iv) p=0.229; and between iii) and iv) p=0.138. This is the first investigation where two modes of CV test, VA, and AA, for bleed-positive and bleed-negative CRC patients were used as the endpoint. The AA reading of the CV test showed higher DA in bleed-positive than in bleed-negative CRC patients.

Effectiveness of Colorectal Cancer (CRC) Screening on All-Cause and CRC-Specific Mortality Reduction: A Systematic Review and Meta-Analysis.

(1) Background: The aim of this study was to pool and compare all-cause and colorectal cancer (CRC) specific mortality reduction of CRC screening in randomized control trials (RCTs) and simulation models, and to determine factors that influence screening effectiveness. (2) Methods: PubMed, Embase, Web of Science and Cochrane library were searched for eligible studies. Multi-use simulation models or RCTs that compared the mortality of CRC screening with no screening in general population were included. CRC-specific and all-cause mortality rate ratios and 95% confidence intervals were calculated by a bivariate random model. (3) Results: 10 RCTs and 47 model studies were retrieved. The pooled CRC-specific mortality rate ratios in RCTs were 0.88 (0.80, 0.96) and 0.76 (0.68, 0.84) for guaiac-based fecal occult blood tests (gFOBT) and single flexible sigmoidoscopy (FS) screening, respectively. For the model studies, the rate ratios were 0.45 (0.39, 0.51) for biennial fecal immunochemical tests (FIT), 0.31 (0.28, 0.34) for biennial gFOBT, 0.61 (0.53, 0.72) for single FS, 0.27 (0.21, 0.35) for 10-yearly colonoscopy, and 0.35 (0.29, 0.42) for 5-yearly FS. The CRC-specific mortality reduction of gFOBT increased with higher adherence in both studies (RCT: 0.78 (0.68, 0.89) vs. 0.92 (0.87, 0.98), model: 0.30 (0.28, 0.33) vs. 0.92 (0.51, 1.63)). Model studies showed a 0.62-1.1% all-cause mortality reduction with single FS screening. (4) Conclusions: Based on RCTs and model studies, biennial FIT/gFOBT, single and 5-yearly FS, and 10-yearly colonoscopy screening significantly reduces CRC-specific mortality. The model estimates are much higher than in RCTs, because the simulated biennial gFOBT assumes higher adherence. The effectiveness of screening increases at younger screening initiation ages and higher adherences.

Randomized Trial of Facilitated Adherence to Screening Colonoscopy vs Sequential Fecal-Based Blood Test

Colorectal cancer (CRC) screening guidelines include screening colonoscopy and sequential high-sensitivity fecal occult blood testing (HSgFOBT), with expectation of similar effectiveness based on the assumption of similar high adherence. However, adherence to screening colonoscopy compared with sequential HSgFOBT has not been reported. In this randomized clinical trial, we assessed adherence and pathology findings for a single screening colonoscopy vs sequential and nonsequential HSgFOBTs. Participants aged 40-69 years were enrolled at 3 centers representing different clinical settings. Participants were randomized into a single screening colonoscopy arm vs sequential HSgFOBT arm composed of 4-7 rounds. Initial adherence to screening colonoscopy and sequential adherence to HSgFOBT, follow-up colonoscopy for positive HSgFOBT tests, crossover to colonoscopy, and detection of advanced neoplasia or large serrated lesions (ADN-SERs) were measured. There were 3523 participants included in the trial; 1761 and 1762 participants were randomized to the screening colonoscopy and HSgFOBT arms, respectively. Adherence was 1473 (83.6%) for the screening colonoscopy arm vs 1288 (73.1%) for the HSgFOBT arm after 1 round (relative risk [RR], 1.14; 95% CI, 1.10-1.19; P ≤ .001), but only 674 (38.3%) over 4 sequential HSgFOBT rounds (RR, 2.19; 95% CI, 2.05-2.33). Overall adherence to any screening increased to 1558 (88.5%) in the screening colonoscopy arm during the entire study period and 1493 (84.7%) in the HSgFOBT arm (RR, 1.04; 95% CI, 1.02-1.07). Four hundred thirty-six participants (24.7%) crossed over to screening colonoscopy during the first 4 rounds. ADN-SERs were detected in 121 of the 1473 participants (8.2%) in the colonoscopy arm who were adherent to protocol in the first 12 months of the study, whereas detection of ADN-SERs among those who were not sequentially adherent (n= 709) to HSgFOBT was subpar (0.6%) (RR, 14.72; 95% CI, 5.46-39.67) compared with those who were sequentially adherent (3.3%) (n= 647) (RR, 2.52; 95% CI, 1.61-3.98) to HSgFOBT in the first 4 rounds. When including colonoscopies from HSgFOBT patients who were never positive yet crossed over (n= 1483), 5.5% of ADN-SERs were detected (RR, 1.50; 95% CI, 1.15-1.96) in the first 4 rounds. Observed adherence to sequential rounds of HSgFOBT was suboptimal compared with a single screening colonoscopy. Detection of ADN-SERs was inferior when nonsequential HSgFOBT adherence was compared with sequential adherence. However, the greatest number of ADN-SERs was detected among those who crossed over to colonoscopy and opted to receive a colonoscopy. The effectiveness of an HSgFOBT screening program may be enhanced if crossover to screening colonoscopy is permitted. gov, Number: NCT00102011.

Optimization of screening strategies for colorectal cancer based on fecal DNA and occult blood testing.

Fecal DNA and occult blood testing have been gradually developed for colorectal cancer (CRC) screening. Comparison of different testing strategies for these methods in CRC screening is in urgent need. This study aims to examine the efficacy of different testing strategies including multi-target fecal DNA testing, qualitative and quantitative fecal immunoassay tests (FITs). Fecal samples were collected from patients diagnosed by colonoscopy. Tests using fecal DNA, quantitative FIT or qualitative FIT were performed on same fecal samples. Efficiency of different testing strategies within different populations was investigated. For high-risk populations (CRC and advanced adenoma), the positive rate of the three methods alone was 74.3-80%; the positive predictive values (PPVs) ranged from 37.3% to 77.8%, and the negative predictive values (NPVs) ranged from 86.3% to 92.2%. For combined testing strategies, the positive rate was 71.4-88.6%, PPVs ranged from 38.3% to 86.2%, and NPVs ranged from 89.6% to 92.9%. Parallel fecal multi-target DNA test and quantitative FIT appears to be superior when using a combined testing strategy. For the normal population, no significant difference was identified in efficacy between these methods when used alone and in combination. Single testing strategy among the three methods is more suitable for the general population screening, and the combined testing strategy is more suitable for high-risk populations screening. The use of different combination strategies may have superiority in CRC high-risk population screening, but cannot conclude significant differences which may be attributed to the small sample size, large samples controlled trials are needed.

The Influence of Social Determinants on Cancer Screening in a Medicaid Sample

Little attention has been paid to the influence of individually measured social determinants of health on cancer screening tests in the Medicaid population. Analysis was conducted on 2015-2020 claims data from a subgroup of Medicaid enrollees from the District of Columbia Medicaid Cohort Study (N=8,943) who were eligible for colorectal (n=2,131), breast (n=1,156), and cervical cancer (n= 5,068) screening. Participants were grouped into four distinct social determinants of health groups on the basis of their responses to social determinants of health questionnaire. This study estimated the influence of the four social determinants of health groups on the receipt of each screening test using log-binomial regression adjusted for demographics, illness severity, and neighborhood-level deprivation. The receipt of cancer screening tests was 42%, 58%, and 66% for colorectal, cervical, and breast cancer, respectively. Those in the most disadvantaged social determinants of health group were less likely to receive a colonoscopy/sigmoidoscopy than those in the least disadvantaged one (adjusted RR=0.70, 95% CI=0.54, 0.92). The pattern for mammograms and Pap smears was similar (adjusted RR=0.94, 95% CI=0.80, 1.11 and adjusted RR=0.90, 95% CI=0.81, 1.00, respectively). In contrast, participants in the most disadvantaged social determinants of health group were more likely to receive fecal occult blood test than those in the least disadvantaged one (adjusted RR=1.52, 95% CI=1.09, 2.12). Severe social determinants of health measured at the individual level are associated with lower cancer preventive screening. A targeted approach that addresses the social and economic adversities that affect cancer screening could result in higher preventive screening rates in this Medicaid population.

A118 BALLOON-ASSISTED ENTEROSCOPY TIMING INCREASES DIAGNOSTIC YIELD IN PATIENTS WITH OVERT OBSCURE GASTROINTESTINAL BLEEDING: A RETROSPECTIVE STUDY

Abstract Background Obscure gastrointestinal bleeding (OGIB) is defined as bleeding from an unknown etiology despite initial investigations with upper endoscopy and colonoscopy, of which 75-80% is attributed to a small bowel (SB) source. OGIB poses a significant diagnostic and therapeutic challenge, resulting in high morbidity and mortality with increased utilization of health care resources. Balloon-assisted enteroscopy (BAE) is a useful procedure for the evaluation and management of small bowel bleeding, with reported diagnostic and therapeutic rates up to 87% and 80%, respectively. Purpose This retrospective study aims to evaluate the diagnostic and therapeutic yields in a large cohort of adult patients presenting with different subtypes of OGIB who have undergone BAE, as well as to assess for association between various patient and disease factors, and clinical outcomes. Method We performed a retrospective review of 1057 cases of BAE at a large quaternary referral centre between 2016 to 2021 and 158 OGIB cases were identified. Sex, age, and, preprocedural variables including indication, time from video capsule endoscopy (VCE) to BAE and subclassification of SB bleed were collected. Endoscopic modality, findings, and therapeutic interventions were used to calculate diagnostic and therapeutic yields. The association between the timing of BAE relative to VCE and clinical outcomes including rebleeding rate, diagnostics and therapeutic yields were assessed. Bleeding free-survival was estimated using Kaplan-Meier function. All data analyses were performed with SPSS. Result(s) The overall diagnostic yield of BAE was 74%. Patients with active overt bleeding were found to have a statistically significant higher yield compared to those with inactive overt bleeding (94% vs 67%, P= 0.03). The therapeutic yield was 51%, with a significantly higher rate of injection therapy and hemoclip placement in those with active overt bleeding compared to those with inactive overt and occult bleeding (P&amp;lt; 0.001). BAE performed within 72 hours of overt GI bleeding was found to have a statistically significant higher diagnostic yield when compared to procedures performed after 72 hours (94% vs 67%, p =0.05). Univariable analysis revealed higher diagnostic yield in patients requiring transfusion within the past 12 months (P= 0.02) Finally, rebleeding-free survival in all patients at 1 year and 5 years was 98% and 68%, respectively. Image Conclusion(s) Balloon-assisted enteroscopy continues to be an effective diagnostic and therapeutic modality for the investigation of obscure gastrointestinal bleeding. Our retrospective study shows a higher diagnostic yield in those presenting with active overt GI bleed as well as those who underwent BAE within 72 hours of overt GI bleeding. Furthermore, patients who required transfusion within the past 12 months are more likely to have a positive BAE finding. Please acknowledge all funding agencies by checking the applicable boxes below None Disclosure of Interest None Declared

The Clinical Significance of Septin 9 and Colon Cancer Specific Antigen-2 (CCSA-2) in Colorectal Cancer.

Colorectal cancer (CRC) is a major health problem Worldwide, Egypt shows a high rate of early CRC in the world as 35% of 1,600 Egyptian CRC patients were under 40 with threefold increased risk of death within 5 years. DNA methylation-based biomarkers as methylated Septin9 (mSEPT9) has a promising role for detecting CRC. As well as set of nuclear matrix proteins associated with changes in the nuclear structure/architecture. detection of these nuclear proteins resulted in identification of biomarkers that are specific for colon cancer. Particular interest has been placed on colon cancer specific antigen-2(CCSA-2). A total of 30 newly diagnosed CRC patients, 7 colonic adenoma patients, and 15 age- and sex-matched control subjects were recruited in this study. Plasma mSEPT9was assayed by Epi procolon kit, CCSA-2 by ELISA and, Occult blood in stool by Guaiac-based fecal occult blood test. The level of Colon Cancer mSEPT9 and CCSA-2 were carried on CRC patients both preoperatively and three months postoperatively. mSEPT9 has 96.7% sensitivity and 95.5% specificity in differentiating colorectal cancer patients from non-malignant cases. Also, our study showed a highly statistically significant difference between the pre and three months postoperative expression of mSEPT9 in colorectal cancer as there was a dramatically decrease in the expression of mSEPT9 postoperatively (p value < 0.001). The CCSA-2 at the cutoff level of >1.43 would provide 93.3% sensitivity and 90.9% specificity in differentiation between malignant and non-malignant cases. Also, the study showed that there is a statistically significant difference between colorectal cancer patients preoperatively and postoperatively according to CCSA-2 with dramatic decrease in its level postoperatively (p value > 0.001). The plasma SEPT9 DNA methylation level and Serum CCSA-2 could be used as promising non-invasive methods for observing the CRC patients postsurgical response to predict the occurrence of complete remission or relapses.