The Importance of Digital Rectal Examination in Identifying Early-Onset Rectal Malignancies.

Colorectal cancer (CRC) is the second most diagnosed cancer and the second leading cause of cancer-related deaths in the United States. Rectal cancers, specifically, are the second most common cancer of the large intestine. Although once perceived as a disease of the elderly, the incidence of early-onset CRC (EO-CRC), classified as occurring in individuals less than 50 years old, has been paradoxically increasing. Although the incidence of rectal cancers has increased, the digital rectal exam (DRE) continues to be an underutilized physical exam maneuver when a patient presents with red-flag symptoms. Here, we present a case of a 38-year-old male from West Virginia who was referred to general surgery for complaints of rectal bleeding attributed to internal hemorrhoids. After undergoing a colonoscopy, the patient was found to have a rectal mass consistent with adenocarcinoma. We describe the importance of identifying red-flag signs to keep colorectal malignancy in the differential diagnosis in a young patient and highlight the importance of performing rectal exams to identify rectal cancers early to expedite treatment.

Overall Polyp Detection Rate as a Surrogate Measure for Screening Efficacy Independent of Histopathology: Evidence from National Endoscopy Database.

Adenoma detection rate (ADR) is challenging to measure, given its dependency on pathology reporting. Polyp detection rate (PDR) (percentage of screening colonoscopies detecting a polyp) is a proposed alternative to overcome this issue. Overall PDR from all colonoscopies is a relatively novel concept, with no large-scale studies comparing overall PDR with screening-only PDR. The aim of the study was to compare PDR from screening, surveillance, and diagnostic indications with overall PDR and evaluate any correlation between individual endoscopist PDR by indication to determine if overall PDR can be a valuable surrogate for screening PDR. Our study analyzed a prospectively collected national endoscopy database maintained by the National Institute of Health from 2009 to 2014. Out of 354,505 colonoscopies performed between 2009-2014, 298,920 (n = 110,794 average-risk screening, n = 83,556 average-risk surveillance, n = 104,770 diagnostic) met inclusion criteria. The median screening PDR was 25.45 (IQR 13.15-39.60), comparable with the median overall PDR of 24.01 (IQR 11.46-35.86, p = 0.21). Median surveillance PDR was higher at 33.73 (IQR 16.92-47.01), and median diagnostic PDR was lower at 19.35 (IQR 9.66-29.17), compared with median overall PDR 24.01 (IQR 11.46-35.86; p < 0.01). The overall PDR showed excellent concordance with screening, surveillance, and diagnostic PDR (r > 0.85, p < 0.01, 2-tailed). The overall PDR is a reliable and pragmatic surrogate for screening PDR and can be measured in real time, irrespective of colonoscopy indication.

Giant Ulcerated Colonic Lipoma in an Asymptomatic Patient.

Colonic lipomas are benign masses typically found incidentally during routine screening exams. They rarely grow large enough to become symptomatic. While most colonic lipomas are small and do not lead to complications, giant lipomas can present with symptoms ranging from changes in bowel patterns and mild abdominal pain to bowel obstruction. Ulcerated giant colonic lipomas are even more rare findings on screening colonoscopies. Diagnosis in this context can be challenging, and resection is warranted in most cases. Here, we describe an asymptomatic patient who presented for a screening colonoscopy and was found to have a giant ulcerated colonic lipoma.

Effect of the SARS-CoV-2 pandemic on colorectal cancer diagnosis and prognosis.

BACKGROUND AND STUDY AIMS: Our aim was to determine the impact of the SARS-CoV-2 pandemic on the diagnosis and prognosis of colorectal cancer (CRC). PATIENTS AND METHODS: This prospective cohort study included individuals diagnosed with CRC between March 13, 2019 and June 20, 2021 across 21 Spanish hospitals. Two time periods were compared: prepandemic (from March 13, 2019 to March 13, 2020) and pandemic (from March 14, 2020 to June 20, 2021, lockdown period and 1 year after lockdown). RESULTS: We observed a 46.9% decrease in the number of CRC diagnoses (95% confidence interval (CI): 45.1%-48.7%) during the lockdown and 29.7% decrease (95% CI: 28.1%-31.4%) in the year after the lockdown. The proportion of patients diagnosed at stage I significantly decreased during the pandemic (21.7% vs. 19.0%; p = 0.025). Centers that applied universal preprocedure SARS-CoV-2 PCR testing experienced a higher reduction in the number of colonoscopies performed during the pandemic post-lockdown (34.0% reduction; 95% CI: 33.6%-34.4% vs. 13.7; 95% CI: 13.4%-13.9%) and in the number of CRCs diagnosed (34.1% reduction; 95% CI: 31.4%-36.8% vs. 26.7%; 95% CI: 24.6%-28.8%). Curative treatment was received by 87.5% of patients diagnosed with rectal cancer prepandemic and 80.7% of patients during the pandemic post-lockdown period (p = 0.002). CONCLUSIONS: The COVID-19 pandemic has led to a decrease in the number of diagnosed CRC cases and in the proportion of stage I CRC. The reduction in the number of colonoscopies and CRC diagnoses was higher in centers that applied universal SARS-CoV-2 PCR screening before colonoscopy. In addition, the COVID-19 pandemic has affected curative treatment of rectal cancers.

A Case Report of Pulmonary Edema Secondary to Large Volume Bowel Preparation in a High-Risk Patient with Multiple Cardiopulmonary Co-Morbidities.

Introduction: Polyethylene glycol 3,350 and electrolytes is a commonly prescribed bowel regimen for colonoscopy preparation with an overall excellent safety profile, though prior reports have demonstrated risk of volume overload. Case Presentation: A 55-year-old man with significant cardiopulmonary co-morbidities was admitted for acute hypoxic respiratory failure and subsequent evaluation for lung transplant. As part of his pretransplant evaluation, colon cancer screening was advised. Despite multiple days of bowel preparation, his stools contained sediment. Unfortunately, he developed pulmonary edema due to prolonged bowel preparation. Conclusion: While bowel preparation is considered generally safe, our case report highlights the importance of judicious use with monitoring in high-risk individuals.

The Efficacy of Real-time Computer-aided Detection of Colonic Neoplasia in Community Practice: A Pragmatic Randomized Controlled Trial.

BACKGROUND & AIMS: The use of computer-aided detection (CADe) has increased the adenoma detection rates (ADRs) during colorectal cancer (CRC) screening/surveillance in randomized controlled trials (RCTs) but has not shown benefit in real-world implementation studies. We performed a single-center pragmatic RCT to evaluate the impact of real-time CADe on ADRs in colonoscopy performed by community gastroenterologists. METHODS: We enrolled 1100 patients undergoing colonoscopy for CRC screening, surveillance, positive fecal-immunohistochemical tests, and diagnostic indications at one community-based center from September 2022 to March 2023. Patients were randomly assigned (1:1) to traditional colonoscopy or real-time CADe. Blinded pathologists analyzed histopathologic findings. The primary outcome was ADR (the percentage of patients with at least 1 histologically proven adenoma or carcinoma). Secondary outcomes were adenomas detected per colonoscopy (APC), sessile-serrated lesion detection rate, and non-neoplastic resection rate. RESULTS: The median age was 55.5 years (interquartile range, 50-62 years), 61% were female, 72.7% were of Hispanic ethnicity, and 9.1% had inadequate bowel preparation. The ADR for the CADe group was significantly higher than the traditional colonoscopy group (42.5% vs 34.4%; P = .005). The mean APC was significantly higher in the CADe group compared with the traditional colonoscopy group (0.89 ± 1.46 vs 0.60 ± 1.12; P < .001). The improvement in adenoma detection was driven by increased detection of <5 mm adenomas. CADe had a higher sessile-serrated lesion detection rate than traditional colonoscopy (4.7% vs 2.0%; P = .01). The improvement in ADR with CADe was significantly higher in the first half of the study (47.2% vs 33.7%; P = .002) compared with the second half (38.7% vs 34.9%; P = .33). CONCLUSIONS: In a single-center pragmatic RCT, real-time CADe modestly improved ADR and APC in average-detector community endoscopists. (ClinicalTrials.gov number, NCT05963724).

Factors associated with negative colonoscopy in participants with a positive faecal immunochemical test from the Danish Colorectal Cancer Screening Program - a population-based study.

AIM: In the Danish Colorectal Cancer Screening Program (DCCSP), 37% of participants undergoing colonoscopy have a negative result with no obvious findings that can be attributed to a positive faecal immunochemical test (FIT). The aim of this work was to identify predictors for a negative colonoscopy in DCCSP participants with a positive FIT. METHOD: We included 73 655 FIT-positive DCCSP participants using the Danish Colorectal Cancer Screening Database and linked their screening results with data from several other national health registers. We stratified participants by all predictors, and compared them using multivariate logistic regression analysis. Results are reported as odds ratios (ORs). RESULTS: We found that having a condition linked to gastrointestinal bleeding, for example fissures, haemorrhoids and inflammatory bowel disease, was strongly associated with the probability of having a negative colonoscopy [OR 2.77 (95% CI 2.59, 2.96)]. FIT concentration was inversely related to the probability of a negative colonoscopy, the OR decreased steadily from 0.79 (95% CI 0.75, 0.83) in the 40-59 µg/g group, to 0.44 (95% CI 0.42, 0.46) in the ≥200 µg/g group. Women had a 1.64 (95% CI 1.59, 1.70) times higher probability of a negative colonoscopy than men. CONCLUSION: Our findings indicate that baseline conditions linked to gastrointestinal bleeding are an associating factor with having a negative colonoscopy. The same is true for low FIT concentration and female sex. Further studies with similar findings could suggest that an incorporation of these factors into a personalized screening approach by differentiating between diagnostic modalities could improve the process for the participant while alleviating the health care system.

Missed Opportunities: the Timing and Frequency of Screening Colonoscopy in Patients That Develop Esophageal Adenocarcinoma.

INTRODUCTION: Screening colonoscopy (SC) is widely accepted and has been shown to decrease the rate of colorectal cancer death. Guidelines and acceptance of screening for Barrett's esophagus (BE) are less established despite the fact that esophageal adenocarcinoma (EA) remains the fastest increasing cancer in the USA. The aim of this study was to assess the timing and frequency of SC in patients ultimately found to have EA and to evaluate the presence of symptoms and risk factors that might have prompted an esophagogastroduodenoscopy (EGD) and potentially earlier diagnosis of the EA. METHODS: A retrospective chart review was performed to identify all patients who were referred to a single center with esophageal cancer between July 2016 and November 2022. Patients with any histology other than adenocarcinoma were excluded. RESULTS: There were 221 patients referred with EA. Of these, a SC had been done prior to the diagnosis of EA in 108 patients (49%): 96 men and 12 women. A total of 203 SC had been done (range 1-7 per patient), and 47% of patients had more than 1 SC. The median interval from the last SC to the diagnosis of EA was 2.9 years. At the time of SC, gastroesophageal reflux disease (GERD) symptoms or chronic acid suppression medication use was reported by 81% of patients, and 80% had an American Society of Gastrointestinal Endoscopy (ASGE) indication for a screening EGD. Only 19 patients (18%) that had a SC had an EGD at any time prior to the diagnosis of EA, and in these patients, 74% had erosive esophagitis or BE. The EA in most patients was stage III or IV and associated with lymph node metastases. CONCLUSIONS: Nearly one-half of patients ultimately diagnosed with EA had one or more SCs, and most of these patients had GERD symptoms, were using acid suppression medications or had an ASGE indication for a screening EGD. Despite this, only 18% had an EGD prior to the EA diagnosis. The addition of an EGD at the time of SC in these patients may have allowed the detection of BE or EA at an early, endoscopically curable stage and represents a missed opportunity to intervene in the natural history of this disease.

A Rare Case of Colon Cancer in a Young Patient With HIV Infection: Is it Time for New Colon Cancer Screening Guidelines for HIV Patients?

Patients with human immunodeficiency virus (HIV) infection have a higher prevalence of colonic neoplasms than the general population. In these patients, tumors develop at an earlier age, are diagnosed at more advanced stages, and have a dismal prognosis. Current guidelines recommend initiating colon cancer screening in HIV patients at the age of 45 which is consistent with screening age in the general population. We present a rare case of colon cancer diagnosed in an HIV-infected patient at a young age of only 34 years. Therefore, we recommend early screening for colon cancer in HIV patients than the general population.

[Évaluation de la gravité du cancer colorectal dépisté dans le contexte de la crise sanitaire liée au COVID19 en région Ile-de-France]. / Evaluation of the severity of screened colorectal cancer in the context of the health crisis linked to COVID19 in Ile-de-France region.

BACKGROUND: After the announcement in March 2020 of the COVID-19 pandemic, colorectal cancer (CRC) screening programs were suspended in several countries. Compared to the lesions detected during previous campaigns, this study aims to assess the severity of CRC detected during the 2020 screening campaign in Île-de-France, the French region most affected by the 1st wave of the pandemic. METHODS: The descriptive and etiological study included all faecal immunochemical test (FIT) results carried out between January 2017 and December 2020 on people aged 50-74, living in Île-de-France. First, the proportion of colonoscopies performed within one month (One-month-colo) following FIT; the yield of colonoscopy (proportion of colonoscopies with a neoplasm lesion among those performed) and CRC severity (TNM Classification, Level-0: T0/N0/M0, Level-1: T1/T2/N0/M0, Level-2: T3/T4/N0/M0; Level-3: T3/T4/N1/M0; Level-4: M1) were described in 2020 compared to previous campaigns (2017, 2018, and 2019). Subsequently, the link between the level of CRC severity and the predictive factors, including campaign year and time to colonoscopy, was analysed using polytomous multivariate regression. RESULTS: The one-month-colo (2017: 9.1% of 11,529 colonoscopies; 2018: 8.5% of 13,346; 2019: 5.7% of 7,881; 2020: 6.7% of 11,040; p < 0.001), the yield (65.2%, 64.1%, 62.4%, 60.8% respectively, p < 0.001) were significantly different between campaigns. The proportion of CRC level-4 (4.8% in 2017 (653 CRC); 7.6% in 2018 (674 CRC); 4.6% in 2019 (330 CRC) and 4.7% in 2020 (404 CRC); p < 0.29) was not significantly different between campaigns. The probability of having CRC with a high severity level was inversely related to the time to colonoscopy but not to the campaign year. Compared to patients having undergone colonoscopy within 30 days, the odds were significantly reduced by 60% in patients having undergone colonoscopy after 7 months (adjusted Odds-Ratio: 0.4 [0.3; 0.6]; p < 0.0001). CONCLUSIONS: The French indicators were certainly degraded before the first wave of the COVID-19. The delay in access to colonoscopy as well as its extension induced by the COVID-19 crisis had no impact in terms of cancer severity, due to a discriminatory approach prioritizing patients with evident symptoms.

Rectosigmoid Adenocarcinoma Presenting As Nine Days of Constipation.

We report the case of a 56-year-old male presenting with nine days of constipation and absence of flatus without any improvement and who had received conservative management after recent admission at an external hospital. Upon further investigation, the patient was diagnosed with rectosigmoid adenocarcinoma and was successfully surgically treated without any perioperative complications. This case highlights the importance of early detection and interventions necessary to prevent progression of colorectal adenocarcinoma. Easily manageable symptoms such as constipation may require further evaluation by implementing a constipation scoring system to avoid missed diagnoses such as cancer and metastasis. Therefore, the association between constipation and colorectal carcinoma warrants further research investigations as well as clinician awareness to prevent life-threatening complications.

Incidentally Discovered Mucosal Prolapse of the Colon During Colorectal Cancer Screening: A Case Report.

Colonic mucosal prolapse syndrome is a rare type of non-neoplastic non-inflammatory colorectal polyps that can mimic neoplastic lesions. We present a case of a 65-year-old man with mucosal prolapse syndrome, incidentally, discovered during colorectal cancer screening. The patient was asymptomatic, and his physical exam and laboratory test results were unremarkable. During a colonoscopy, the physician removed three small tubular adenomas and two pedunculated polyps suspicious of neoplasms. Retroflexion revealed small internal hemorrhoids. The histology of the larger polyps revealed mucosal prolapse features, while the smaller polyps displayed features consistent with tubular adenomas. Management involves the removal of associated polyps during colonoscopy, followed by surveillance colonoscopy to detect any recurrent polyps or early signs of colorectal cancer. Accurate diagnosis is crucial to avoid unnecessary interventions and ensure appropriate management.

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.

Withdrawal time in colonoscopy, past, present, and future, a narrative review.

Background and Objective: Colonoscopy is a time proven, safe, and gold standard screening method for colorectal cancer (CRC). In order to achieve its objectives, quality markers have been defined for colonoscopy, including withdrawal time (WT). WT is defined as the time spent from reaching the cecum or terminal ileum till the end of procedure in colonoscopies without any additional interventions. This review aims to provide evidence on WT efficacy and future directions. Methods: We conducted a comprehensive literature search of articles evaluating WT. Search was limited to English language articles from all peer-reviewed journals. Key Content and Findings: The seminal study by Barclay et al., led to setting of a minimum WT of 6 minutes as the recommended amount for colonoscopy, per 2006 American College of Gastroenterology (ACG) taskforce. Since then, many observational studies have confirmed the efficacy of 6 minutes. Recently, multiple large multicenter trials suggest WT of 9 minutes as the alternative for better outcomes. Recently, novel Artificial Intelligence (AI) models have shown promise in improving WT and other outcomes and proved an exciting tool in the armamentarium of gastroenterologists. Some of these tools encourage the endoscopists to check the blind spots and clean the residual stool. This has shown to improve both WT and ADR. We recommend an improvement of these models to consider risk factors like adenoma detection in current and prior scopes to guide endoscopists spend time in each segment. Conclusions: In conclusion, new evidence demonstrates that WT of 9 minutes is better than 6 minutes. Future trends point toward an individualized AI-based approach combining real time and baseline data and guiding the endoscopist on how much time to spend in every segment of the colon in every colonoscopy procedure.

The relationship between colon polyps and colonic diverticulosis: a retrospective review.

Background: Colonic diverticulosis and colon polyps are common findings on colonoscopy. There is currently no consensus regarding a possible connection between the development of polyps and diverticulosis. Multiple research studies have sought to analyze whether the presence of both conditions is associated with the development of colorectal cancer. Our study aims to add to this body of data and to better assess the relationship between diverticulosis and colon polyps. Methods: A retrospective chart review was performed of all patients who underwent screening and diagnostic colonoscopies between January 2011 and December 2020. Data collection included patient demographics; number, pathology, and location of colon polyps; incidence of colon cancer; and presence and location of colonic diverticulosis. Results: Our study demonstrated that the overall presence of diverticulosis in any location increases the likelihood of having nearby colon polyps, regardless of subtype. The presence of left colonic diverticulosis was particularly associated with adjacent adenomatous and non-adenomatous colon polyps. Conclusions: Colonic diverticulosis in any location may lead to an increased incidence of adenomatous colon polyps. It is important to perform careful examination of the mucosa surrounding colon diverticulosis to avoid missing colon polyps.

Appendiceal Inversion Presenting as a Cecal Polypoid Mass on Screening Colonoscopy: A Case Report and Review of Available Diagnostic Adjuncts to Differentiate Benign From Malignant Colorectal Pathology.

Appendiceal inversion is uncommon. It may be a benign finding or seen in association with malignant pathology. When detected, it masquerades as a cecal polyp which poses a diagnostic dilemma with malignancy in the differential. In this report, we highlight a case of a 51-year-old patient with an extensive surgical history as a newborn in the setting of omphalocele and intestinal malrotation, who was found to have a 4 cm cecal polypoid growth on screening colonoscopy. He underwent a cecectomy for tissue diagnosis. Ultimately, the polyp was found to be an inverted appendix without evidence of malignancy. Currently, suspicious colorectal lesions which cannot be removed by polypectomy are primarily addressed with surgical excision. We reviewed the literature for available diagnostic adjuncts to better differentiate benign from malignant colorectal pathology. The application of advanced imaging and molecular technology will allow for improved diagnostic accuracy and subsequent operative planning.

Clinical Characteristics and Main Findings of Colonoscopy in Tripoli Central Hospital: A Cross-Sectional Study of 1858 Patients.

Introduction Colonoscopy is used to detect colorectal abnormalities, including inflammatory bowel disease, polyps, cancers, and other colorectal lesions. We aimed to analyze the demographic and clinical characteristics, main findings, and indications of patients who underwent colonoscopy in the Surgery department of Tripoli Central Hospital in Libya. Methods The study data were retrospectively extracted from the medical in and out-patient records of individuals who underwent colonoscopy procedures between December 2009 and December 2016 in the general surgery department of Tripoli General Hospital. Results A total of 1858 patients underwent colonoscopy during the study period with a mean age of 51.7 ± 18.5 years. Hematochezia was the most common patient complaint (530; 28.5%), followed by constipation (354; 19.1%), and weight loss (178; 9.6%), respectively. Seven-hundred sixty-five (765; 41.2%) participants completed the procedure, 420 (22.6%) did not, and 673 (36.2%) participants failed the colonoscopy. The most common reasons for procedure failure were failed preparation (609; 55.7%), followed by patient intolerance (251; 23.0%), and obstructive lesions (229; 21.0%). The most common finding was colonic masses, followed by polyps (29.0% and 20.8%, respectively). Conclusion This study describes the characteristics of colonoscopy patients in the largest surgical center in Libya over seven years. Hematochezia and chronic constipation were the most common complaints among the participants with reported complaints. Half of the colonoscopy procedures are incomplete or failed due to the lack of patient preparation. Colonic masses and polyps were the most common among the reported colonoscopic findings. Future research to increase the quality of colonoscopy service and patient preparations in Libya is required.

Supply and quality of colonoscopy according to the characteristics of gastroenterologists in the French population-based colorectal-cancer screening program.

BACKGROUND: Since its complete roll-out in 2009, the French colorectal cancer screening program (CRCSP) experienced 3 major constraints [use of a less efficient Guaiac-test (gFOBT), stopping the supply of Fecal-Immunochemical-Test kits (FIT), and suspension of the program due to the coronavirus disease 2019 (COVID-19)] affecting its effectiveness. AIM: To describe the impact of the constraints in terms of changes in the quality of screening-colonoscopy (Quali-Colo). METHODS: This retrospective cohort study included screening-colonoscopies performed by gastroenterologists between Jan-2010 and Dec-2020 in people aged 50-74 living in Ile-de-France (France). The changes in Quali-colo (Proportion of colonoscopies performed beyond 7 mo (Colo_7 mo), Frequency of serious adverse events (SAE) and Colonoscopy detection rate) were described in a cohort of Gastroenterologists who performed at least one colonoscopy over each of the four periods defined according to the chronology of the constraints [gFOBT: Normal progress of the CRCSP using gFOBT (2010-2014); FIT: Normal progress of the CRCSP using FIT (2015-2018); STOP-FIT: Year (2019) during which the CRCSP experienced the cessation of the supply of test kits; COVID: Program suspension due to the COVID-19 health crisis (2020)]. The link between each dependent variable (Colo_7 mo; SAE occurrence, neoplasm detection rate) and the predictive factors was analyzed in a two-level multivariate hierarchical model. RESULTS: The 533 gastroenterologists (cohort) achieved 21509 screening colonoscopies over gFOBT period, 38352 over FIT, 7342 over STOP-FIT and 7995 over COVID period. The frequency of SAE did not change between periods (gFOBT: 0.3%; FIT: 0.3%; STOP-FIT: 0.3%; and COVID: 0.2%; P = 0.10). The risk of Colo_7 mo doubled between FIT [adjusted odds ratio (aOR): 1.2 (1.1; 1.2)] and STOP-FIT [aOR: 2.4 (2.1; 2.6)]; then, decreased by 40% between STOP-FIT and COVID [aOR: 2.0 (1.8; 2.2)]. Regardless of the period, this Colo_7 mo's risk was twice as high for screening colonoscopy performed in a public hospital [aOR: 2.1 (1.3; 3.6)] compared to screening-colonoscopy performed in a private clinic. The neoplasm detection, which increased by 60% between gFOBT and FIT [aOR: 1.6 (1.5; 1.7)], decreased by 40% between FIT and COVID [aOR: 1.1 (1.0; 1.3)]. CONCLUSION: The constraints likely affected the time-to-colonoscopy as well as the colonoscopy detection rate without impacting the SAE's occurrence, highlighting the need for a respectable reference time-to-colonoscopy in CRCSP.

An Evaluation of Critical Factors for the Cost-Effectiveness of Real-Time Computer-Aided Detection: Sensitivity and Threshold Analyses Using a Microsimulation Model.

BACKGROUND & AIMS: The use of computer-aided detection (CAD) increases the adenoma detection rates (ADRs) during colorectal cancer (CRC) screening/surveillance. This study aimed to evaluate the requirements for CAD to be cost-effective and the impact of CAD on adenoma detection by endoscopists with different ADRs. METHODS: We developed a semi-Markov microsimulation model to compare the effectiveness of traditional colonoscopy (mean ADR, 26%) to colonoscopy with CAD (mean ADR, 37%). CAD was modeled as having a $75 per-procedure cost. Extensive 1-way sensitivity and threshold analysis were performed to vary cost and ADR of CAD. Multiple scenarios evaluated the potential effect of CAD on endoscopists' ADRs. Outcome measures were reported in incremental cost-effectiveness ratios, with a willingness-to-pay threshold of $100,000/quality-adjusted life year. RESULTS: When modeling CAD improved ADR for all endoscopists, the CAD cohort had 79 and 34 fewer lifetime CRC cases and deaths, respectively, per 10,000 persons. This scenario was dominant with a cost savings of $143 and incremental effectiveness of 0.01 quality-adjusted life years. Threshold analysis demonstrated that CAD would be cost-effective up to an additional cost of $579 per colonoscopy, or if it increases ADR from 26% to at least 30%. CAD reduced CRC incidence and mortality when limited to improving ADRs for low-ADR endoscopists (ADR <25%), with 67 fewer CRC cases and 28 CRC deaths per 10,000 persons compared with traditional colonoscopy. CONCLUSIONS: As CAD is implemented clinically, it needs to improve mean ADR from 26% to at least 30% or cost less than $579 per colonoscopy to be cost-effective when compared with traditional colonoscopy. Further studies are needed to understand the impact of CAD when used in community practice.