Positive Fecal Occult Blood Test Research Articles

Risk Factors for Colorectal Adenoma and Cancer in Comprehensive Health Checkups: Usefulness of Gamma-Glutamyltransferase

Background/Objectives: In this study, we aimed to determine the risk factors for colorectal adenoma/cancer by studying patients who underwent comprehensive health checkups and were referred to a hospital because of positive fecal occult blood. Methods: A total of 529 patients were referred to hospital for a positive fecal occult blood test after a comprehensive health checkup at the participating center over a period of 5 years, from January 2018 to December 2022. Patients diagnosed with colorectal adenoma or cancer using colonoscopy were included in the case group, while those diagnosed with no abnormality, diverticulum, or hemorrhoids were included in the control group. Results: Of the 529 referred patients, 503 underwent colonoscopy. A total of 18 colorectal cancers and 191 colorectal adenomas were detected, and there were no tumors, diverticula, or hemorrhoids in any of the 208 patients. Polyps, either hyperplastic or of unknown pathology, were found in 86 patients. A comparison of the case and control groups showed that gamma-glutamyltransferase (GGT) was an independent and significant risk factor for colorectal adenoma or cancer, in addition to previously known risk factors such as male sex, older age, high body mass index, and alcohol consumption. Conclusions: For patients with a positive fecal occult blood test, in addition to traditional risks such as obesity, older age, male sex, and alcohol consumption, identifying those with high GGT levels is recommended to help find colorectal adenoma/cancer.

Trousseau syndrome with recurrent cerebral infarction as the first oneset in a gastrointestinal malignant tumor patient: A case report.

Trousseau syndrome (TS) is a thrombosis disorder characterized by a hypercoagulable state linked to underlying malignancies, resulting in various thrombotic events such as deep vein thrombosis, pulmonary embolism, and arterial thrombosis. This syndrome serves as a crucial indicator of malignancy and can often be the first sign of an underlying tumor. In this case, we report a case of gastrointestinal malignant tumor as the first onset, and analyzes its clinical characteristics to improve the clinicians' understanding of this kind of disease. A 69-year-old woman was admitted to the hospital 4 times in 1 month for cerebral infarction. The patient was admitted several times with a new cerebral infarction lesion and a high D-dimer level, a persistently positive fecal occult blood test, and a gastrointestinal tumor was later found. The patient was diagnosed with TS, attributed to her underlying malignancy. During hospitalization, the patients were treated with aspirin for antiplatelet, esomeprazole for protection of gastric mucosa, atorvastatin for lowering blood lipids, butylphthalein for improvement of collateral circulation, edaravone dextrocamphorol for scavenging oxygen free radicals, and betahistine hydrochloride tablets for preventing dizziness. The patient's condition improved significantly after initial treatment, but died of the tumor a year after discharge. Currently, TS has a complex and varied clinical presentation and is relatively difficult to diagnose, especially in patients with an unknown tumor history. Focus should be placed on patients with recurrent cerebral infarctions and increased D-dimer levels, and anticoagulation may be an effective treatment for patients with TS.

Surgical indication and management of obstructive colonic metastasis from primary lung adenocarcinoma: report of a case and review of the literature

BackgroundColonic metastasis from lung cancer is very rare and is typically associated with poor prognosis. Herein, we report the case of a patient who achieved intermediate-term survival using a multimodal treatment approach, including chemotherapy, immunotherapy, radiotherapy, and surgical resection for obstructive colonic metastasis from primary lung adenocarcinoma.Case presentationA woman in her 50s presented with anemia and a positive fecal occult blood test. Computed tomography revealed a tumor in the right upper lobe of the lung with mediastinal lymphadenopathy and wall thickening in the transverse colon. Colonoscopy revealed a stricture involving 50% of the colonic lumen. Biopsy revealed a poorly differentiated adenocarcinoma positive for CK-7 and TTF-1, very focally positive for napsin A, and negative for CK-20 and CDX-2. Furthermore, positron emission tomography/CT (PET/CT) showed a high maximum standardized uptake value (SUVmax) of 8.2 in the iliac bone. Based on these findings, the patient was diagnosed with primary lung adenocarcinoma with simultaneous metastasis to the transverse colon and iliac bone (cT4N3M1c, cStage IVB).After receiving first-line chemotherapy with atezolizumab, pemetrexed, and carboplatin, the tumors shrank after 4 courses. Subsequently, the patient received maintenance therapy with atezolizumab and pemetrexed. However, the tumor enlarged after 10 courses. Second-line chemotherapy with docetaxel and ramucirumab (3 courses) failed to achieve tumor reduction. Colonoscopy revealed an impassable colonic tumor. Nineteen months after diagnosis, surgery was planned for imminent intestinal obstruction.We determined that the colonic tumor was resectable, because laparoscopic exploration revealed no other metastases. The tumor was resected by partial colectomy with ileocolonic anastomosis. The postoperative course was uneventful. Pathological examination revealed a resection margin that was negative for malignancy, and the histological type was consistent with metastatic lung adenocarcinoma.The patient then received nab-paclitaxel therapy; however, she developed symptoms of superior vena cava syndrome after 3 courses. The patient received palliative irradiation (30 Gy/10 fr) followed by nivolumab. She soon developed a solitary brain metastasis, and stereotactic irradiation was planned. After 3 courses of nivolumab, the metastasis was reduced significantly, and stereotactic brain irradiation was canceled. The lung tumor and mediastinal lymphadenopathy gradually shrank, and the patient survived for 13 months after surgery without disease progression.ConclusionsIn this case, surgical resection of colonic metastasis from primary lung adenocarcinoma may have contributed to the short-term prognosis as a bridge-to-next available multimodal treatment.

Laparoscopic sleeve gastrectomy as a bridge to colorectal cancer surgery for obese patients: a case report

BackgroundSevere obesity greatly influences the difficulty of colorectal cancer surgery and has been reported to prolong operative time, increase the rate of laparotomy, and elevate increase postoperative complications. We investigated the efficacy of laparoscopic sleeve gastrectomy (LSG) for preoperative weight loss to ensure safe colorectal cancer surgery.Case presentationA 51 year-old female with a body mass index of 43.5 kg/m2 was referred to our hospital due to a positive fecal occult blood test. She was diagnosed as having a laterally spreading tumor of the cecum by colonoscopy. Endoscopic submucosal dissection was attempted but proved difficult due to the size of the lesion and its proximity to the appendiceal orifice. We planned bariatric surgery prior to colorectal surgery, and she underwent LSG without any complications. Seven months after the LSG, she had lost 30.7 kg, and her final preoperative body mass index was 27.8 kg/m2. Single-incision laparoscopic ileocecal resection was then performed safely. The pathological diagnosis was adenocarcinoma in adenoma of the cecum, TisN0M0.ConclusionLSG was effective in reducing visceral fat and making it possible to perform safe surgery for colorectal cancer in a severely obese patient.

Laparoscopic resection of a descending colon tumor with right-sided fixation of the sigmoid colon: a case report

BackgroundIntestinal malrotation is a condition in which the process of counterclockwise rotation and fixation to the peritoneum and retroperitoneum during fetal life is incomplete. In adults, it is generally asymptomatic and is often discovered incidentally. We report a case of laparoscopic partial resection of the descending colon for a tumor of the descending colon with a rare form of intestinal malrotation in which the inferior mesenteric artery ran symmetrically and the sigmoid colon was fixed to the dorsal cecum and right-sided retroperitoneum.Case presentationA 75-year-old man was referred to our department of internal medicine due to a positive fecal occult blood test. Lower endoscopy revealed a laterally spreading tumor in the descending colon, and endoscopic submucosal dissection was attempted; however, this procedure was difficult, and the patient was referred to our department for surgical treatment. Contrast-enhanced computed tomography revealed that the endoscopic clip was located in the descending colon on the right side, the inferior mesenteric artery was symmetrical, and the sigmoid colon was located on both the right and dorsal sides of the cecum. Laparoscopic ileocecum and sigmoid colon mobilization was performed from the left side of the patient. After the completion of sigmoid colon mobilization, which returned the sigmoid colon and descending colon to anatomical normalcy, laparoscopic partial resection of the descending colon was performed. Based on the results of a histopathological examination, a granular type of laterally spreading tumor was diagnosed. The patient was discharged uneventfully on postoperative day 8.ConclusionsDetailed preoperative imaging and surgical simulation are necessary for abdominal surgery involving intestinal malrotation.

Choosing Your Endoscopist: A Retrospective Single-Centre Cohort Study.

Background Colorectal cancer is one of the most commoninternal malignancies affecting Australians, and colonoscopy is widely accepted as a part of comprehensivelarge bowel assessment. Different specialties perform colonoscopies, most commonly general surgeons and gastroenterologists. Analysing performance outcomes against benchmarks allows insight into inter-specialty differences and enables the improvement of overall service provision and quality. Methods We performed a retrospective single-centre cohort study on 2086 patients undergoing colonoscopies by seven surgeons (S) and nine gastroenterologists (G) between July 2021 and June 2023. Primary outcomes were comparative caecal intubation rates (CIR), photo documentation rates (PDR), documented withdrawal rates (DWR), withdrawal times (WT), and adenoma detection rates (ADR). Secondary outcomes characterised adenoma frequency, optimal WT, and indications for colonoscopies. Results We found significant differences in CIR (S: 94.9%, 990/1043;G: 99%, 1033/1043, P<0.01), PDR (S: 95.9%, 949/990; G: 99.1%, 1024/1033, P<0.01), DWR (S: 17.4%, 181/1043; G: 87.3%, 911/1043, P<0.01), WT >6 minutes (S: 82.3%, 149/181; G: 97.8%, 891/911, P<0.01), and ADR (S: 37.9%, 193/509; G: 59.7%, 421/705, P<0.01). Subgroup analysis revealed adenoma frequency peaked at 50-70 years oldand optimal WT was ≥9 minutes. We demonstrated surgeons mainly perform colonoscopies for diverticulitis surveillance, abnormal imaging, post-cancer resections, and rectal bleeding, but gastroenterologists predominantly investigate bowel symptoms, polyp surveillance, positive faecal occult blood test, and anaemia. Conclusion Despite both specialties surpassing national standards in CIR and ADR, there were significant differences in performance indicators. We believe ADR differences could be explained by different indications specialties perform colonoscopies for. Increasing WT ≥9 minutes could improve ADR, and education on the usage of withdrawal timer on endoscopes will improve DWR.

Colorectal Cancer Detection during a Screening Awareness Campaign in a High-Risk Region in Oman.

Colorectal cancer (CRC) constitutes the third most frequently diagnosed cancer in Oman. This study report the result of a community based screening campaign to promote the early detection and explore the associated risk factors of CRC amongst Omani population. We launched a colorectal cancer awareness campaign in Oman's South Ash Sharqiyah Governorate between January and March, 2023. We conducted a stratified random study including 688 adult Omani participants aged over 40 years old. Local Health Centers collected the questionnaire forms. Fecal occult blood tests (FOBTs) were carried out at Local Health Centers; while medical professionals performed the colonoscopy examination in Sur University Hospital. Overall, the screening response rate was 68.8%. The data indicated that 8.1% of the total sample yielded positive FOBTs; of whom, 85.7% were aged 40-59 years old and 67.9% were obese or overweight. Abnormal colonoscopy was reported in 7 participants. One participant had a confirmed CRC of stage I. Screening and early detection campaign can have effect and increase the rate of early detection among population in Oman.

Decreased Positive Fecal Occult Blood Tests and Delayed Medical Presentation for Colorectal Cancer during the Initial COVID-19 Pandemic Period: A Single-center Experience.

This study aimed to investigate the impact of the COVID-19 pandemic on the examination and treatment of colorectal cancer (CRC) and on the behaviors of patients and practitioners. This is a retrospective analysis of the CRC patients who presented to our department between April 2019 and March 2021 and underwent surgery. Clinical presentation of CRC and time from symptom onset to medical presentation were compared between the control (April 2019 to March 2020, n=124) and COVID-19 pandemic periods (April 2020 to March 2021, n=111). Two hundred and thirty-five patients were reviewed. The rate of positive fecal occult blood tests was significantly lower during the COVID-19 pandemic period (13.5 vs. 25.0%, P = 0.027). Among the symptomatic patients who had melena and abdominal symptoms, the time from symptom onset to medical presentation was significantly longer during the COVID-19 period (115 vs. 31 days, P < 0.001). In addition, the interval between presenting to a practitioner and being referred to our department was similar between the two periods (19 vs. 13 days, P = 0.092). There were no significant differences in the stage of cancer between the two periods. The rate of preoperative sub-obstruction was significantly higher during the COVID-19 period (41.4 vs 23.4%, P = 0.003). There was no significant difference in overall survival and recurrence-free survival between two periods. Hesitation to seek examination and treatment for CRC was observed in patients but not in practitioners during the COVID-19 pandemic period. The prognosis did not change.

Appendiceal goblet cell adenocarcinoma newly classified by WHO 5th edition: a case report (a secondary publication)

BackgroundAppendiceal goblet cell adenocarcinoma (AGCA) is a newly proposed cancer type in the 5th edition of the WHO Classification of Tumours in 2019. We experienced this rare form of appendiceal primary neoplasm.Case presentationAn 85-year-old male presented a positive fecal occult blood test. A series of imagings revealed a type 1 tumor, located on the appendiceal orifice. The subsequent biopsy made the diagnosis of signet-ring cell carcinoma. Consequently, he underwent the laparoscopic-assisted ileocecal resection. Initially, the tumor was suspected to be a Goblet cell carcinoid (GCC). There was a discrepancy between the histological and immunostaining findings: the tumor cells exhibited morphological similarities to GCCs, however displayed limited staining upon immunostaining. Ultimately, we concluded that the tumor should be classified as AGCA, by following WHO 5th Edition. AGCA represents a newly categorized subtype of adenocarcinomas. Because of our preoperative suspicion of malignancy, we performed tumor resection with regional lymph node dissection, despite the fact that most appendiceal malignant tumors are typically identified after an appendectomy.ConclusionWe experienced a case that provides valuable insights into the comprehension of AGCA, a recently established pathological entity in the WHO 5th Edition. This article is an acceptable secondary publication of a case report that appeared in Azuma et al. (J Jpn Surg Assoc 83:1103–1108, 2022)

Navigating the Labyrinth: When the "Mesenterium Commune" Turns Colonoscopy into an Endoscopic Rollercoaster.

These images involved the case of a 51-year-old woman who had a history of chronic abdominal pain, iron deficiency, and diarrhoea but no blood or mucus in her stool. She had never undergone major abdominal surgery, and her past medical evaluation diagnosed her with celiac disease, leading to the adoption of a gluten-free diet alleviating most of her gastrointestinal symptoms. However, years later, her abdominal pain returned, so she underwent an abdominal ultrasound, revealing non-specific bowel loop dilation, and a weakly positive faecal occult blood test led to a colonoscopy. Despite many efforts to advance the scope beyond the transverse colon, colonoscopy was arduous and not complete, even after several changes in decubitus and abdominal compressions. Therefore, a virtual colonoscopy was conducted, revealing no intraluminal masses, but the entire colon was located on the left side of the abdomen. Indeed, the results showed sigma and that most of the colon was curled up in the small pelvis. This rare anatomical variant, known as "Mesenterium commune" (MC), is a type of gut malrotation that develops in childhood due to a lack of omphalomesenteric loop rotation during the embryonic period. This condition can lead to episodes of intestinal obstruction, potentially resulting in an acute abdomen and leading to surgical correction. Symptoms include chronic recurring abdominal pain, nausea, vomiting, and occasionally bloody stools. Few cases of this extremely rare condition have been reported in the literature so far.

Laparoscopic sigmoid colectomy for transverse colonic varices due to an inferior mesenteric arteriovenous fistula

BackgroundColonic varices are a rare gastrointestinal anomaly often associated with portal hypertension. Arteriovenous fistula (AVF) in the inferior mesenteric artery (IMA) region is even rarer. Diagnosis and treatment of these entities present unique challenges, especially when the IMA is involved.Case presentationA 48-year-old man with a history of cholecystectomy presented with after a positive fecal occult blood test. Investigations revealed varices from the splenic flexure to the transverse colon and suspected AVF in the IMA region. Given the high risk and low efficacy of endoscopic and radiological interventions, laparoscopic sigmoidectomy was performed. This surgical approach successfully addressed both the AVF and the associated varices.ConclusionThis case underscores the importance of surgical intervention for AVF and colonic varices in the IMA region, particularly when other treatment options pose high risks and have limited efficacy. The favorable postoperative outcome in this case highlights the effectiveness of carefully chosen surgical methods when managing such complex and rare conditions.

Screening for colorectal cancer: Study on the shedding cells of feces.

The objective of this study was to explore the enrichment efficiency of an improved fecal exfoliated cell enrichment method and its application in colorectal cancer screening. Samples were collected from a cohort of 100 colorectal cancer patients being treated at the First Hospital of Hebei Medical University from January 2021 to June 2022. Patient samples were equally divided between control and experimental groups corresponding to the enrichment method being applied to the fecal exfoliated cells. Samples consisted of natural stool and bowel cleansing enema solution samples. The control group received the traditional three-layer integrated screen method, and the experimental group used nano-Fe3O4 folic acid magnetic beads to enrich the fecal exfoliated cells. The morphology of the extracted cells was observed by light microscopy through hematoxylin and eosin staining, and the positive rate of fecal occult blood test (FOBT) and the detection rate of colorectal cancer was compared between the two groups. The FOBT-positive rates of natural feces and intestinal cleansing liquid in the control group were 74.00% and 90.00%, respectively, and the FOBT-positive rates of natural feces and intestinal cleansing liquid in the experimental group were 76.00% and 92.00%, respectively. The positive FOBT rate was high, and the difference was statistically significant (P = 0.037 and P = 0.029). The sensitivities of natural fecal exfoliation cytology in the control and experimental groups were 82.00% and 92.00%, respectively. The sensitivity of the experimental group was higher than that of the control group, and the difference was not statistically significant (P = 0.137). The sensitivities of the exfoliated cytology examination of the intestinal cleansing liquid in the control and experimental groups were 88.00% and 98.00%, respectively. The sensitivity of the experimental group was significantly higher than that of the control group, and the difference was statistically significant (P = 0.050). Cell smear results show that the exfoliated cells collected by the three-layer integrated sieve method are unevenly distributed, with overlapping cells and a large number of impurities blurring the background, seriously affecting the observation of cell morphology. The cell structure is blurred, stained unevenly, and arranged in a disorderly manner. The exfoliated cells collected by the nanofolic acid magnetic bead enrichment method are relatively evenly distributed, with no overlapping of cells in patches. The background is clear, and the morphology of each cell can be clearly observed. The cell structure is relatively clear, stained evenly, and distributed evenly. In the cytological examination of fecal exfoliation of colorectal cancer, the nano-Fe3O4 folic acid magnetic bead enrichment method can enrich more target cells compared with the traditional three-layer integrated screen method, improve the detection rate of colorectal cancer, and ensure the exfoliation The cell smears are of higher quality, providing a better sample for clinical assessment of the exfoliated cells. Nano-Fe3O4 folic acid magnetic beads enrichment method can become a simple, efficient, and relatively safe screening method for colorectal cancer, positively affecting early screening developments and diagnosis of colorectal cancer.

Abstract 2317: Development and validation of a colorectal cancer prediction model: A nationwide cohort-based study

Abstract Background: Colorectal cancer (CRC) ranks as the third most prevalent cancer globally and is a major cause of cancer-related mortality. Early diagnosis is critical to increase survival rates. While CRC screening has shown significant benefit, adherence remains low, and there is a need for better tools to identify high-risk patients. Risk prediction models were demonstrated to identify such patients. Aim: To establish an individualized risk prediction model for CRC diagnosis based on Electronic Health Records (EHR). Methods: This is a retrospective cohort study utilizing EHR data of Clalit Health Services (CHS) members aged 50-74 that were eligible for CRC screening, from January 2013 to January 2019. The model was trained to predict CRC diagnosis within two years using approximately 20,000 EHR features including socio-demographic information, laboratory results and medical history. Model performance, as a complementary screening method, was evaluated. Results: The study included 2679 subjects with CRC diagnosis and 1,133,713 subjects without CRC diagnosis. The model was trained on subjects from 2013-2017, and performance was validated on subjects from 2019 and a cohort of subjects that underwent fecal occult blood test (FOBT). Incidence values of CRC among subjects in the top 1% risk scores were higher than baseline (2.3% vs. 0.3%; lift 8.38; P-value &amp;lt;0.001). Characteristics of subjects by risk scores percentiles are presented in Table 1. Cumulative event probabilities increased with higher model scores, indicating a correlation between predicted and actual risk of CRC diagnosis. Model-based risk stratification among subjects with a positive FOBT, identified subjects with more than twice the risk for CRC compared to FOBT alone. Conclusions: We developed an individualized risk prediction model for CRC that can be utilized as a complementary decision support tool for healthcare providers to precisely identify patients at high risk for CRC and refer them to confirmatory testing. Citation Format: Samah Hayek. Development and validation of a colorectal cancer prediction model: A nationwide cohort-based study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2317.

Colorectal cancer screening; colonoscopy and biopsy results in people undergoing colonoscopy due to positive fecal occult blood test.

Screening programs are important for the early detection of colorectal cancer, which is one of the causes of high morbidity and mortality. In this study, we investigated the colonoscopy results, the incidence of adenoma and cancer, and the relationship between test results and cancer in individuals with a positive fecal occult blood test for colorectal cancer screening. Within the scope of the colorectal cancer screening program, colonoscopy was requested for individuals aged 50-70 years who applied to our outpatient clinic with a positive fecal occult blood test. The results were collected and analyzed. The results of the colonoscopy could be obtained in only 237 (56.43%) of the 420 patients who were referred for a colonoscopy because of a positive fecal occult blood test. Colonoscopy results were normal in 15 (6.33%), benign anal disease in 64 (27%), benign colonic disease in 12 (5.06%) and polyp + adenocarcinoma in 146 (61.61%). Pathology results were benign polyp in 37 (15.61%), adenomatous polyp in 86 (36.29%) and adenocarcinoma in 23 (9.71%). Quantitative test results were higher in the adenomatous polyp + adenocarcinoma group and statistically significant (p= 0.03). Individuals with positive fecal occult blood tests, especially those with high quantitative test results, should be encouraged to have a colonoscopy, and they should be warned about the high probability of adenomatous polyps and colorectal cancer.

Rectally obtained fecal samples can be used for fecal occult blood testing in dogs, and fecal immunochemical tests do not detect canine or feline blood.

The first objective was to determine if the sample collection method (naturally voided vs digital rectal examination collection) affected fecal occult blood test (FOBT) results. The second objective was to assess the ability of human fecal hemoglobin immunochemical tests to detect canine and feline blood. 308 privately owned dogs, healthy and sick. Guaiac FOBTs were performed on paired voided and rectally obtained canine fecal samples. The kappa statistic was used to assess agreement between the 2 collection methods, and a multivariate regression model was used to identify factors associated with a positive FOBT. Two fecal immunochemical tests (FITs; Hemosure One Step and OC-Light S) were tested with serially diluted human, canine, and feline blood. Voided and rectally obtained samples showed strong FOB-positivity agreement (k = 0.80), with 92.5% concordance and only 13/308 dogs negative on void but positive on rectal. Multivariate analysis showed dogs with gastrointestinal disease (P = .0008, rectal; P = .0001, void) were more likely and heavier dogs (P = .0037, rectal; P = .0022 void) were less likely to test FOBT positive. Health status, fasting status, NSAID use, and age were associated with FOBT results on univariate, but not multivariate, analysis. FITs did not detect canine or feline blood at any concentration while human blood performed as expected. Rectally obtained fecal samples can be reliably used for FOBTs. Human FITs may not be suitable for companion animals, but evaluation of other available tests is needed.

A108 AN EVALUATION OF IMPLEMENTATION OF A CENTRALIZED REFERRAL AND BOOKING PROCESS ON WAIT TIMES FOR COLONOSCOPIES

Abstract Background Colonoscopies in the majority of centres in Ontario are booked by individual endoscopists via their individual offices (practices). As such, wait times for procedures will vary significant from centre to centre, or even from endoscopist to endoscopist at the same centre, depending on individual expertise, experience, procedure types, and local availability of endoscopic resources. This system could lead to significant variability in access to care for patients. Aims This study analyzed the effect of implementing a centralized referral and booking process for colonoscopy, for a specific indication, at a single centre in Ontario. Methods This was a single centre retrospective study analyzing wait times for patients that underwent a colonoscopy at Cambridge Memorial Hospital (CMH) between April 2017 to July 2022 for either positive fecal occult blood test (FOBT) or fecal immunochemistry test (FIT). The province of Ontario transitioned from FOBT to FIT as the primary tool for colon cancer screening in 2019. Prior to this transition, colonoscopy for positive FOBT performed at CMH were booked by individual endoscopists, with wait times from referral to procedure having great variability. In conjunction with Ontario’s transition to FIT for colon cancer screening, all endoscopists at CMH agreed to participate in a centralized referral and booking process specifically for colonoscopy for positive FIT indication. A chart review of all patients undergoing colonoscopy for either FOBT (non central booking) or FIT (central booking). Patients that self-delayed were excluded. Wait times (WT) was calculated as time between date of referral and date of procedure. The effect of the centralized booking system on wait times was then assessed using statistical analysis. Results In total, 344 patients were included for analysis from before March 2019 (non centralized booking process). The average WT in this group was determined to be 99.2 days (range 50-171 days), of which 147 patients had a WT of less than 56 days (42.7%). In contrast, a total 572 patients were included for analysis after March 2019 (centralized booking process), the average WT was determined to be 44.2 days (range 32-59 days), of which, 526 patients had a WT of less than 56 days (92.0%). The centralized booking process reduced average wait times by 55 days (55.4%), and improved procedure WTs meeting mandated time frame of 56 days by 49.3%. This improvement in wait times was most pronounced for endoscopists with the longest wait times in a non centralized system. Conclusions The implementation of a centralized referral and booking process (for a single indication for colonoscopy) was associated with significantly reduced WTs. These findings suggest a centralized referral and booking process (for well defined clinical needs) can potentially significantly improve patient wait times. Funding Agencies None

Colonic diverticulosis as an isolated colonoscopy finding for iFOBT-positive patients

Colonic diverticular disease is a common medical condition throughout the world. It is one of the most common findings during the endoscopic evaluation of the colon, such as colonoscopy. A retrospective cohort single-centre study was carried out for all patients referred for colonoscopy with positive immunochemical faecal occult blood test (iFOBT) results in 2016-2018, mostly within The National Bower Cancer Screening Program (NBCSP) in QLD, Australia. The cohort of 319 patients were isolated from all iFOBT-positive individuals with such finding as a diverticular disease. Colonic diverticulosis affected the patients above 43 years old with positive iFOBT, more males than females in this study. In most cases, colonoscopy consisted of benign findings, and diverticular disease was revealed in 47.7% of the patients with such indication for colonoscopy as positive iFOBT. 28.8% of the patients were diagnosed with colonic diverticulosis only. The sigmoid colon was affected by diverticulosis in 96.2% of the cases. Overall, the colorectal cancer (CRC) diagnosis rate of 2.7% for the patients in the positive FOBT cohort (Group A) is comparable with other studies. However, the diverticulosis group's CRC rate of 1.6% (Group B) was lower than in available published data.

Circulating tumor DNA (ctDNA) positivity and its association with clinicopathological characteristics by novel blood-based test for colorectal cancer (CRC) screening from a multi-center large cohort: COSMOS-CRC-01.

69 Background: Blood-based CRC screening has yielded performance comparable to stool-based screening tests and may be a modality that addresses the adherence gap in CRC screening. To investigate the diagnostic performance and its clinical relevance, we evaluated the test performance of a blood-based CRC screening test in a large cohort of individuals enriched for advanced colorectal neoplasia and early CRCs. Methods: 501 individuals presenting to ten institutions in Japan from 2020 to 2021 for treatment of advanced adenomas (AAs) or CRCs were consented and provided a pre-treatment blood sample (40mL whole blood in Streck cfDNA blood collection tubes). All eligible individuals underwent surgery or endoscopic resection within 30 days after sample collection and the pathological specimens were reviewed to determine cancer histology and stage, as well as AA histology. Pre-treatment blood samples were analyzed with a multi-modal (genomic and epigenomic) cfDNA CRC detection assay (Shield, Guardant Health, USA). Final cfDNA results were correlated with clinical data to determine the association of clinicopathological characteristics with test sensitivity. This study is registered as a clinical trial under UMIN000037765. Results: 451/501 (90%) individuals met inclusion/exclusion criteria and provided adequate blood samples that passed testing quality control criteria. Median age at consent was 67.4 years (range 31 – 92). 44% were female. 214/451 (47%) had a prior positive fecal occult blood test (FOBT). Of individuals with a negative or unknown FOBT testing, 161/237 (68%) had GI symptoms (e.g. abdominal pain, bloody/narrowing stool, constipation/diarrhea). The test identified 88% (268/305) of CRCs, including 71% (79/111) Stage I, 98% (87/89) Stage II, 97% (90/93) Stage III, and 100% (12/12) Stage IV. Overall sensitivity in detecting Stage I-III was 87%. The test identified 37% (54/146) of AAs, including 49% (33/68) of carcinoma in situs and 24% (9/37) of AAs with high-grade dysplasia. Sensitivity for right-sided CRC was 84% (61/73), 87% (59/68) for left-sided CRC, and 90% (148/164) for rectal tumors. Stage I test sensitivity was significantly associated with tumor size (&gt;20mm; p&lt;0.01), left-sided or rectal tumor location (p&lt;0.05), and tumor depth (p&lt;0.01) in univariate analysis, whereas the tumor depth (T2) was the sole factor associated with test positivity (p&lt;0.05) in multivariate analysis. Specificity on this assay is 90% as determined in the ECLIPSE clinical study (NCT04136002). Conclusions: This study evaluates the performance of a blood-based test for CRC and its clinicopathological relevance in a large-scale cohort. In this population enriched for early colorectal neoplasia, the sensitivity was 88% for CRC and 37% for AAs. This performance is consistent with previous reports. Clinical trial information: UMIN000037765 .

Asymptomatic intestinal tuberculosis of the terminal ileum diagnosed on colonoscopy: a case report and literature review.

Colonoscopy is useful in diagnosing intestinal tuberculosis. However, the terminal ileum is generally not examined during routine colonoscopy. Therefore, even with colonoscopy, the diagnosis can be missed in patients with lesions confined to the terminal ileum. Herein, we report the case of an asymptomatic patient with intestinal tuberculosis, in whom a colonoscope insertion into the terminal ileum led to the diagnosis. An asymptomatic 71-year-old man visited our hospital for a colonoscopy after a positive fecal occult blood test. Colonoscopy revealed diffuse edematous and erosive mucosa in the terminal ileum. Mycobacterium tuberculosis was detected by polymerase chain reaction and culture of biopsy specimens from the erosions, leading to the diagnosis of intestinal tuberculosis. The patient was treated with antitubercular agents for 6 months, and a follow-up colonoscopy revealed healing of the lesions. Asymptomatic intestinal tuberculosis may occasionally be detected on colonoscopy following a positive fecal occult blood test and is sometimes confined to the terminal ileum. Therefore, clinicians should consider intestinal tuberculosis in the differential diagnosis of the causes of positive fecal occult blood test results and perform colonoscopies, including observation of the terminal ileum.

Cowden syndrome in a male patient with metachronous triple cancers and various clinical features:a case report

A 66-year-old male patient with a thyroid and nasopharyngeal cancer history visited our hospital because of a positive fecal occult blood test. Total colonoscopy detected sessile or subpedunculated polyps in the ascending colon, sigmoid colon, and rectum. These polyps were endoscopically resected, and the rectal polyp was pathologically diagnosed as adenocarcinoma in adenoma and the others as adenomas. Additionally, multiple sessile lesions were revealed in the sigmoid colon and rectum. A complete gastrointestinal tract examination revealed multiple foci of glycogenic acanthosis in the esophagus, multiple sessile lesions in the stomach, multiple sessile lesions, clubbings (rod-shaped lesions), and venous malformations in the small bowel. Mucocutaneous examination indicated hemangiomas on the body trunk, patchy pigmentation on the glans penis, and keratotic papules in the inguinal region. The National Comprehensive Cancer Network diagnostic criteria for Cowden syndrome were used in this case. The patient met four major and two minor criteria;thus, Cowden syndrome was diagnosed. Moreover, the patient was had phosphatase and tensin homolog deleted on chromosome 10 gene mutation. This is the first reported case of metachronal triple cancers in a male patient with Cowden syndrome, and our results indicate the importance of cancer surveillance.