Colorectal Polyps Research Articles

Therapeutic potential of Phycocyanin in gastrointestinal cancers and related disorders.

Gastrointestinal cancer is the most fatal cancer worldwide. The etiology of gastrointestinal cancer has yet to be fully characterized. Alcohol consumption, obesity, tobacco, Helicobacter pylori and gastrointestinal disorders, including gastroesophageal reflux disease, gastric ulcer, colon polyps and non-alcoholic fatty liver disease are among the several risks factors for gastrointestinal cancers. Phycocyanin which is abundant in Spirulina. Phycocyanin, a member of phycobiliprotein family with intense blue color, is an anti-diabetic, neuroprotective, anti-oxidative, anti-inflammatory, and anticancer compound. Evidence exists supporting that phycocyanin has antitumor effects, exerting its pharmacological effects by targeting a variety of cellular and molecular processes, i.e., apoptosis, cell-cycle arrest, migration and Wnt/β-catenin signaling. Phycocyanin has also been applied in treatment of several gastrointestinal disorders such as, gastric ulcer, ulcerative colitis and fatty liver that is known as a risk factor for progression to cancer. Herein, we summarize various cellular and molecular pathways that are affected by phycocyanin, its efficacy upon combined drug treatment, and the potential for nanotechnology in its gastrointestinal cancer therapy.

Clinical consequences of computer-aided colorectal polyp detection

Background and aimRandomised trials show improved polyp detection with computer-aided detection (CADe), mostly of small lesions. However, operator and selection bias may affect CADe’s true benefit. Clinical outcomes of increased...

Fatty acid desaturase insertion-deletion polymorphism rs66698963 predicts colorectal polyp prevention by the n–3 fatty acid eicosapentaenoic acid: a secondary analysis of the seAFOod polyp prevention trial

BackgroundA fatty acid desaturase (FADS) insertion-deletion (Indel) polymorphism (rs66698963) influences the expression of FADS1, which controls the synthesis of n–6 highly unsaturated fatty acid (HUFA) arachidonic acid (AA). The anti-inflammatory activity of the n–3 HUFA eicosapentaenoic acid (EPA) may be explained by competition with AA for proinflammatory lipid mediator synthesis. A precision medicine approach based on stratification by FADS Indel genotype could identify individuals, who benefit from greatest disease risk reduction by n–3 HUFAs. ObjectivesWe tested the hypothesis that the FADS insertion (I) allele predicts colorectal polyp risk reduction in a secondary analysis of the randomized, placebo-controlled, 2×2 factorial seAFOod polyp prevention trial of EPA 2000 mg daily and aspirin 300 mg daily for 12 mo (ISRCTN05926847). MethodsParticipant Indel genotype was determined by polymerase chain reaction (PCR) blind to trial outcomes. Colorectal polyp outcomes were included in negative binomial (polyp number) and logistic (polyp detection rate [PDR; percentage with one or more polyps]) regression models comparing each active intervention with its placebo. Presence of ≥1 Indel I allele and an interaction term (I allele × active intervention) were covariates. ResultsIn 528 participants with colonoscopy and FADS Indel data, EPA use irrespective of Indel genotype, was not associated with reduced colorectal polyp number (incidence rate ratio [IRR]: 0.92; 95% confidence interval: 0.74, 1.16), mirroring original seAFOod trial analysis. However, the presence of ≥1 I allele identified EPA users with a significant reduction in colorectal polyp number (IRR: 0.50 [0.28, 0.90]), unlike aspirin, for which there was no interaction. Similar findings were obtained for the PDR. ConclusionsThe FADS Indel I allele identified individuals, who displayed colorectal polyp prevention by EPA with a similar effect size to aspirin. Assessment of rs66698963 as a biomarker of therapeutic response to n–3 HUFAs in other populations and healthcare settings is warranted.The seAFOod polyp prevention trial and STOP-ADENOMA study were registered at International Standard Randomised Controlled Trial Number registry as ISRCTN05926847.

Colorectal adenoma detection rate using texture and color enhancement imaging versus white light imaging with chromoendoscopy: a propensity score matching study.

Few studies have evaluated the adenoma detection rate (ADR) of colonoscopy with texture and color enhancement imaging (TXI), a novel image-enhancing technology. This study compares the detection of colorectal polyps using TXI to that using white light imaging (WLI). This single-center retrospective study used propensity-matched scoring based on the patients' baseline characteristics (age, sex, indication, bowel preparation, endoscopist, colonoscope type, and withdrawal time) to compare the results of patients who underwent chromoendoscopy using WLI or TXI at the Toyoshima Endoscopy Clinic. The differences in polyp detection rates and the mean number of detected polyps per colonoscopy were determined between the TXI and WLI groups. After propensity score matching, 1970 patients were enrolled into each imaging modality group. The mean patient age was 57.2±12.5years, and 44.5% of the cohort were men. The ADR was higher in the TXI group than in the WLI group (55.0% vs 49.4%, odds ratio: 1.25). High-risk ADR were more common in the TXI group than in the WLI group (17.6% vs 12.8%; OR: 1.45). The mean number of adenomas per colonoscopy (APC) was higher in the TXI group than in the WLI group (1.187 vs 0.943, OR: 1.12). APC with a flat morphology (1.093 vs 0.848, OR: 1.14) and APC of <6mm (0.992 vs 0.757, OR: 1.16) were higher in the TXI group than in the WLI group. Compared to WLI, TXI improved the ADR in patients who underwent chromoendoscopy based on actual clinical data.

Colorectal Polyp Detection Model by Using Super-Resolution Reconstruction and YOLO

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide. Colonoscopy is the primary method to prevent CRC. However, traditional polyp detection methods face problems such as low image resolution and the possibility of missing polyps. In recent years, deep learning techniques have been extensively employed in the detection of colorectal polyps. However, these algorithms have not yet addressed the issue of detection in low-resolution images. In this study, we propose a novel YOLO-SRPD model by integrating SRGAN and YOLO to address the issue of low-resolution colonoscopy images. Firstly, the SRGAN with integrated ACmix is used to convert low-resolution images to high-resolution images. The generated high-resolution images are then used as the training set for polyp detection. Then, the C3_Res2Net is integrated into the YOLOv5 backbone to enhance multiscale feature extraction. Finally, CBAM modules are added before the prediction head to enhance attention to polyp information. The experimental results indicate that YOLO-SRPD achieves a mean average precision (mAP) of 94.2% and a precision of 95.2%. Compared to the original model (YOLOv5), the average accuracy increased by 1.8% and the recall rate increased by 5.6%. These experimental results confirm that YOLO-SRPD can address the low-resolution problem during colorectal polyp detection and exhibit exceptional robustness.

Flexible Colon Polyp Detection: A Dual Mode Approach for Detection and Segmentation of Colon Polyps with Optional Inpainting for Specular Highlight Mitigation

Flexible Colon Polyp Detection: A Dual Mode Approach for Detection and Segmentation of Colon Polyps with Optional Inpainting for Specular Highlight Mitigation

WSPolyp-SAM: Weakly Supervised and Self-Guided Fine-Tuning of SAM for Colonoscopy Polyp Segmentation

Ensuring precise segmentation of colorectal polyps holds critical importance in the early diagnosis and treatment of colorectal cancer. Nevertheless, existing deep learning-based segmentation methods are fully supervised, requiring extensive, precise, manual pixel-level annotation data, which leads to high annotation costs. Additionally, it remains challenging to train large-scale segmentation models when confronted with limited colonoscopy data. To address these issues, we introduce the general segmentation foundation model—the Segment Anything Model (SAM)—into the field of medical image segmentation. Fine-tuning the foundation model is an effective approach to tackle sample scarcity. However, current SAM fine-tuning techniques still rely on precise annotations. To overcome this limitation, we propose WSPolyp-SAM, a novel weakly supervised approach for colonoscopy polyp segmentation. WSPolyp-SAM utilizes weak annotations to guide SAM in generating segmentation masks, which are then treated as pseudo-labels to guide the fine-tuning of SAM, thereby reducing the dependence on precise annotation data. To improve the reliability and accuracy of pseudo-labels, we have designed a series of enhancement strategies to improve the quality of pseudo-labels and mitigate the negative impact of low-quality pseudo-labels. Experimental results on five medical image datasets demonstrate that WSPolyp-SAM outperforms current fully supervised mainstream polyp segmentation networks on the Kvasir-SEG, ColonDB, CVC-300, and ETIS datasets. Furthermore, by using different amounts of training data in weakly supervised and fully supervised experiments, it is found that weakly supervised fine-tuning can save 70% to 73% of annotation time costs compared to fully supervised fine-tuning. This study provides a new perspective on the combination of weakly supervised learning and SAM models, significantly reducing annotation time and offering insights for further development in the field of colonoscopy polyp segmentation.

Tactics of surgical treatment of children with small intestinal polyps with Peutz–Jeghers syndrome and juvenile polyposis

Tactics of surgical treatment of children with small intestinal polyps with Peutz–Jeghers syndrome and juvenile polyposis

MEGANET: Improved framework with nature inspired approach for colorectal cancer polyp classification

BACKGROUND: Polyps are tumorous growths in the colon or rectal area which can turn into cancer at later stages, thus detection of polyps is very important for timely prevention of colorectal cancer. The aim of the study is to develop a framework to accurately detect polyp images in colonoscopy images. OBJECTIVE: Development of an intelligent framework for classification of colorectal cancer from colon and rectal images. The standard machine learning, convolutional neural networks and ensemble models with nature inspired approach were implemented for this study. Model optimization was performed by varying hyper parameters. The main objective was to find an optimal model with high accuracy, optimized weights and less parameters. METHODS: The deep learning Convolutional Neural Network (CNN) models such as VGG19, ResNet50, EfficientNet, Ensemble Model (EM), and Modified Ensemble CNN with Genetic Algorithm (MEGANET) were implemented for the classification of colon images. RESULTS: Ensemble model was also created with two best performing deep learning models to further achieve higher accuracy of 96%. The ensemble model outperformed the other models in terms of accuracy, precision, recall, and F1 score. But this model has more complexity. The MEGANET, nature inspired evolutionary ensemble CNN model was implemented with transfer learning and genetic algorithms for weights optimization and parameter reduction. It achieved accuracy of 95%, on training data. CONCLUSION: The MEGANET performed similar to EM with less number of parameters on training, validation and test dataset. In future different methods will be implemented to further reduce the parameters and attain reasonable accuracy using MEGANET.

Endoscopic management of giant colonic polyps: a retrospective Italian study.

Polyps greater than 30 mm are classified as "giants". Their endoscopic removal represents a technical challenge. The choice of the endoscopic removal technique is important because it provides a resection sample for precise histopathological staging. This is pivotal for diagnostic, prognostic, and management purposes. From a retrospective analysis, we obtained a sample of 38 giant polyps. Eighteen polypectomies were performed using the epinephrine volume reduction (EVR) method, nine polypectomies utilized endo-looping or clipping methods, and 11 patients underwent surgery. We obtained en bloc resection with the EVR method in all cases; histology confirmed the correct indication for endoscopic resection in all cases. Moreover, no early or delayed complications were observed, and no patient required hospitalization. Using endo-looping or clipping methods, we observed advanced histology in 1/9 (11.1%) cases, while another patient (1/9, 11.1%) had delayed bleeding. Among patients who underwent surgery, 5/11 (45.5%) were deemed overtreated and three had post-surgical complications. We propose EVR as an alternative technique for giant polyp resection due to its safety, effectiveness, cost-efficiency, and the advantage of avoiding the need to postpone polypectomy to a later time. Further prospective studies might help improve this experience and enhance the technique.

Helicobacter pylori infection is associated with the development of sporadic colorectal carcinoma and colorectal adenomatous polyps

Helicobacter pylori (H. pylori) infection is a well-established carcinogen that has been extensively studied in the context of gastric diseases. Recent studies suggested a potential association between H. pylori and the risk of colorectal carcinoma (CRC). However, available data remains insufficient to definitively establish a causal relationship between H. pylori infection and the development of CRC and its precursor lesions. In our study, we reviewed all patients diagnosed with CRC in 2020 at our institution. H. pylori assessment was performed in all 92 CRC specimens by immunohistochemistry. Notably, two of the three patients detected with H. pylori infection are under the age of 50. Subsequently, we reviewed a total of 52 patients under the age of 50 diagnosed with CRC at our institution from 2015 to 2022. Among these patients, H. pylori infection was detected in 7 CRC specimens (13.46 %). All seven patients had adenocarcinoma on the left side of the colon. In exploring the link between H. pylori infection and the risk of developing CRC precursor lesions, we analyzed 242 patients who underwent colonoscopy guided polypectomy and also had stomach biopsies from 2015 to 2022. Of these patients, 21 were proved to be positive for H. pylori infection in the stomach, while the remaining 221 were negative. Among the H. pylori-positive group, 76.19 % (16 patients) exhibited adenomatous polyps, compared to 33.48 % (74 patients) in the H. pylori-negative patients (p=0.0001). However, no H. pylori was detected in any colonic adenomatous polyps. Our findings contribute additional evidence supporting the association between H. pylori infection and the development of sporadic CRC, probably a particular association with early-onset ones. Furthermore, gastric H. pylori infection appears to be linked to the higher prevalence of colonic adenomatous polyps, suggesting that individuals with gastric H. pylori infection may benefit from closer and earlier monitoring through colonoscopy.

Which Drugs are More Effective in Preventing Familial Adenomatous Polyposis Progression based on Network Meta-analysis?

Familial adenomatous polyposis (FAP) is an inherited disorder. At present, an increasing number of medications are being employed to treat FAP; however, only a few have been assessed for their efficacy and safety. Therefore, this study aimed to conduct a network meta-analysis to compare the therapeutic outcomes and adverse drug reactions of all FAP-associated medications. Six relevant databases were searched to identify pertinent randomized controlled trials (RCTs), and information on the dosage and frequency of various drugs was extracted. Additionally, data on changes in polyp counts and dimensions, as well as treatment-related adverse reactions for different medications were collected. The Bayesian method was employed to directly or indirectly compare the impact of different treatment regimens on changes in polyp numbers and diameters, and the safety of the drugs was investigated. CXB at 16 mg/kg/day significantly reduced polyp numbers. Celecoxib at 8 mg/kg/day and sulindac (150 mg twice daily) plus erlotinib (75 mg/day) were effective for tolerant FAP patients. Additionally, EPAFFA 2 g daily and sulindac (150 mg twice daily) plus erlotinib (75 mg/day) emerged as the most effective for reducing polyp size. The most effective treatment for reducing the number of colorectal polyps is celecoxib 16 mg/kg/day. On the other hand, a daily dosage of 2 g EPA-FFA demonstrates the best results in terms of decreasing colorectal polyp diameter.

The Association between Anthropometric Indicators and Colorectal Polyps and Diverticulosis

Abstract Introduction Colonic polyps and diverticulosis are common colon findings on colonoscopy. One of the risk factors of colorectal polyps and diverticulosis is the anthropometric index. Therefore, we aimed to investigate the association between the anthropometric index and colorectal findings. Methods In this cross-sectional study, we included 536 patients referred to Razi Hospital, Rasht, Iran, in 2023 for colonoscopy evaluation. Demographical data, clinical characteristics, and colonoscopy findings were recorded for further analysis. All data were analyzed using SPSS.16 by considering a significant level &lt; 0.05 Results The results showed that 35.4% of the patients had polyps, with the majority having a single polyp. The patient's mean age was 55.94 ± 13.33 years; most were females (54.1%). The most common type of polyp was pedunculated, and most were located in the sigmoid colon. The prevalence of diverticular was 11.4%, most of which were also located in the sigmoid colon. Obesity was significantly associated with an increased risk of polyps, while overweight individuals had a higher risk of diverticula (P &lt; 0.05). Age, rural residence, and low physical activity level were identified as factors associated with an increased risk of polyps and diverticula. Conclusion The findings suggest that obesity and overweight are risk factors for polyps and diverticula, respectively. Further research is warranted to explore additional factors and develop preventive strategies for colorectal diseases. These results support the need for preventive strategies and screening programs to reduce the risk of future colorectal lesions.

Endoscopic scoring indices for assessing disease severity in familial adenomatous polyposis: Systematic review.

Background and study aims There is limited consensus on the optimal method for measuring disease severity in familial adenomatous polyposis (FAP). We aimed to systematically review the operating properties of existing endoscopic severity indices for FAP. Methods We searched MEDLINE, EMBASE, and the Cochrane Library from inception to February 2023 to identify randomized controlled trials (RCTs) that utilized endoscopic outcomes or studies that evaluated the operating properties of endoscopic disease severity indices in FAP. Results A total of 134 studies were included. We evaluated scoring indices and component items of scoring indices, such as polyp count, polyp size, and histology. Partial validation was observed for polyp count and size. The most commonly reported scoring index was the Spigelman classification system, which was used for assessing the severity of duodenal involvement. A single study reported almost perfect interobserver and intra-observer agreement for this system. The InSIGHT polyposis staging system, which was used for assessing colorectal polyp burden, has been partially validated. It showed substantial interobserver reliability; however, the intra-observer reliability was not assessed. Novel criteria for high-risk gastric polyps have been developed and assessed for interobserver reliability. However, these criteria showed a poor level of agreement. Other scoring indices assessing the anal transition zone, duodenal, and colorectal polyps have not undergone validation. Conclusions There are no fully validated endoscopic disease severity indices for FAP. Development and validation of a reliable and responsive endoscopic disease severity instrument will be informative for clinical care and RCTs of pharmacological therapies for FAP.

Appropriate trust in artificial intelligence for the optical diagnosis of colorectal polyps: The role of human/artificial intelligence interaction

Background and AimsComputer-aided diagnosis (CADx) for optical diagnosis of colorectal polyps is thoroughly investigated. However, studies on human-artificial intelligence (AI) interaction are lacking. Aim was to investigate endoscopists’ trust in CADx by evaluating whether communicating a calibrated algorithm confidence improved trust. MethodsEndoscopists optically diagnosed 60 colorectal polyps. Initially, endoscopists diagnosed the polyps without CADx assistance (initial diagnosis). Immediately afterwards, the same polyp was again shown with CADx prediction; either only a prediction (benign or pre-malignant) or a prediction accompanied by a calibrated confidence score (0-100). A confidence score of 0 indicated a benign prediction, 100 a (pre-)malignant prediction. In half of the polyps CADx was mandatory, for the other half CADx was optional. After reviewing the CADx prediction, endoscopists made a final diagnosis. Histopathology was used as gold standard. Endoscopists’ trust in CADx was measured as CADx prediction utilization; the willingness to follow CADx predictions when the endoscopists initially disagreed with the CADx prediction. ResultsTwenty-three endoscopists participated. Presenting CADx predictions increased the endoscopists’ diagnostic accuracy (69.3% initial vs 76.6% final diagnosis, p<0.001). The CADx prediction was utilized in 36.5% (n=183/501) disagreements. Adding a confidence score led to a lower CADx prediction utilization, except when the confidence score surpassed 60. A mandatory CADx decreased CADx prediction utilization compared to an optional CADx. Appropriate trust, utilizing correct or disregarding incorrect CADx predictions was 48.7% (n=244/501). ConclusionsAppropriate trust was common and CADx prediction utilization was highest for the optional CADx without confidence scores. These results express the importance of a better understanding of human-AI interaction.

Diagnostic and prognostic significance of circulating secreted frizzled-related protein 5 in colorectal cancer.

Secreted Frizzled-Related Protein 5 (SFRP5) modulates Wnt signalling pathways, affecting diverse biological processes. We assessed the diagnostic and prognostic value of circulating SFRP5 (cSFRP5) in colorectal cancer (CRC) METHODS: Plasma cSFRP5 concentrations were measured using enzyme-linked immunosorbent assay (ELISA) in healthy donors (n = 133), individuals diagnosed with CRC (n = 449), colorectal polyps (n = 85), and medical conditions in other organs including cancer, inflammation, and benign states (n = 64). Patients with CRC, polyps, and other conditions showed higher cSFRP5 levels than healthy individuals (p < 0.0001). Receiver operating characteristic curves comparing healthy donors with medical conditions, polyps and CRC were 0.814 (p < 0.0001), 0.763 (p < 0.0001) and 0.762 (p < 0.0001), respectively. In CRC, cSFRP5 correlated with patient age (p < 0.0001), tumour stage (p < 0.0001), and histological differentiation (p = 0.0273). Levels, adjusted for patient age, sex, plasma age and collection institution, peaked in stage II versus I (p < 0.0001), III (p = 0.0002) and IV (p < 0.0001), were lowest in stage I versus III (p = 0.0002) and IV (p = 0.0413), with no difference between stage III and IV. Elevated cSFRP5 levels predicted longer overall survival in stages II-III CRC (univariate: HR 1.82, 95% CI: 1.02-3.26, p = 0.024; multivariable: HR 2.34, 95% CI: 1.12-4.88, p = 0.015). This study confirms cSFRP5 levels are elevated in CRC compared to healthy control and reveals a correlation between elevated cSFRP5 and overall survival in stages II-III disease.

Novel physiological analysis using blood flow velocity for colonic polyps: Pilot study.

Real-time visualization of red blood cell flow inside subepithelial microvessels is performed with magnifying endoscopy. However, microvascular blood flow velocity in the colorectum has not been investigated. Here, we aimed to evaluate the blood flow velocity of microvessels of colonic polyps and to compare it with that of surrounding mucosa. We examined 50 lesions, including 30 adenomas (ADs) and 20 hyperplastic polyps (HPs). Blood flow velocities of lesions and their surrounding mucosa were evaluated using magnifying blue laser imaging (BLI) prior to endoscopic resection. Calculation of mean blood flow velocities was based on mean movement distance of one tagged red blood cell using split video images of magnifying BLI. Mean microvascular blood flow velocity was significantly lower in ADs (1.65±0.66 mm/sec; range 0.46-2.90) than in HPs (2.83±1.10 mm/sec; 1.07-4.50) or the surrounding mucosa (3.73±1.11 mm/sec; 1.80-6.20; P <0.001). The blood flow velocity rate compared with the surrounding mucosa was significantly lower in ADs (0.41±0.16; 0.10-0.82) than in HPs (0.89±0.25; 0.46-1.51; P <0.001). We found that mean microvascular blood flow velocity was significantly lower in ADs than in HPs and the surrounding non-neoplastic mucosa. These findings indicate that a novel dynamic approach with microvascular blood flow velocity using magnifying endoscopy may be useful in assessing physiological differences between ADs and HPs.

RNA Therapy for Oncogenic NRAS-Driven Nevi Induces Apoptosis

RAS proteins regulate cell division, differentiation and apoptosis via multiple downstream effector pathways. Oncogenic RAS variants are the commonest drivers in cancers, however they also drive many benign lesions predisposing to malignancy, such as melanocytic naevi, thyroid nodules, and colonic polyps. Reversal of these benign lesions could reduce cancer incidence, however the effects of oncogenic RAS have been notoriously difficult to target with downstream pathway inhibitors. Here we show effective suppression of oncogenic and currently undruggable NRASQ61K in primary cells from melanocytic naevi using siRNA targeted to the recurrent causal variant. This results in striking reduction in expression of ARL6IP1, a known inhibitor of endoplasmic reticulum stress-induced apoptosis not previously linked to NRAS. We go on to show that a single dose of siRNA in primary cells triggers an apoptotic cascade, in contrast to treatment with a MEK inhibitor. Protective packaging of the targeted siRNA into lipid nanoparticles permits successful delivery into a humanised mouse model of melanocytic naevi, and results in variant NRAS knockdown in vivo. These data show that RAS-induced protection from apoptosis is involved in persistence of NRAS-driven melanocytic naevi and anticipate that targeted siRNA could form the basis of clinical trials for RAS-driven benign tumours.

Surgeon assessment of significant rectal polyps using white light endoscopy alone and in comparison to fluorescence-augmented AI lesion classification

PurposePerioperative decision making for large (> 2 cm) rectal polyps with ambiguous features is complex. The most common intraprocedural assessment is clinician judgement alone while radiological and endoscopic biopsy can provide periprocedural detail. Fluorescence-augmented machine learning (FA-ML) methods may optimise local treatment strategy.MethodsSurgeons of varying grades, all performing colonoscopies independently, were asked to visually judge endoscopic videos of large benign and early-stage malignant (potentially suitable for local excision) rectal lesions on an interactive video platform (Mindstamp) with results compared with and between final pathology, radiology and a novel FA-ML classifier. Statistical analyses of data used Fleiss Multi-rater Kappa scoring, Spearman Coefficient and Frequency tables.ResultsThirty-two surgeons judged 14 ambiguous polyp videos (7 benign, 7 malignant). In all cancers, initial endoscopic biopsy had yielded false-negative results. Five of each lesion type had had a pre-excision MRI with a 60% false-positive malignancy prediction in benign lesions and a 60% over-staging and 40% equivocal rate in cancers. Average clinical visual cancer judgement accuracy was 49% (with only ‘fair’ inter-rater agreement), many reporting uncertainty and higher reported decision confidence did not correspond to higher accuracy. This compared to 86% ML accuracy. Size was misjudged visually by a mean of 20% with polyp size underestimated in 4/6 and overestimated in 2/6. Subjective narratives regarding decision-making requested for 7/14 lesions revealed wide rationale variation between participants.ConclusionCurrent available clinical means of ambiguous rectal lesion assessment is suboptimal with wide inter-observer variation. Fluorescence based AI augmentation may advance this field via objective, explainable ML methods.

Patient reported colonoscopy barriers: A cross sectional survey.

e23149 Background: As a leading cause of cancer-related death in the United States, colorectal cancer (CRC) screening is an acceptable cost-effective strategy to reducing mortality indices in the country. 10-yearly colonoscopy screening is the most effective with a mortality reduction of 73%. Despite this, CRC screening rates remain low. The purpose of this study was to describe barriers associated with colonoscopy screening in primary care settings. Methods: Postage pre-paid return envelopes and surveys were sent to all established patients aged &gt; 50 from primary care practices (n = 4) in an employed physician group; the group also serves as a residency continuity clinic for a community teaching hospital. Variables included demographics and literature-reported barriers to colonoscopy screening. Whether or not a patient had a colonoscopy (including if &gt; 10 years since a colonoscopy) was compared to patient reported barriers and demographics. Statistical significance was set at p &lt; 0.05; strength of association was measured by Cramer’s V. Results: Average age of patients was 62 + 6 years; 61.4% were female; 35.3% were privately insured; and 10.3% were non-white. Older patients were slightly more likely to get screened, 63 + 6 years vs. 60 + 7 years (p = 0.006). Neither race, sex, insurance guarantor, education, marital status or income were associated with screening. Rate of colonoscopy screening in this series was 76.7% (n = 276/360), which was greater than rates reported by CDC for Ohio. In those screened, the rate of colonic or rectal polyps was remarkably noted to be up to 47.5% (131/276). The most important barriers to colonoscopy screening were knowledge of insurance coverage (p &lt; 0.001; Cramer’s V = 0.216, p &lt; 0.001); transportation to procedure (p = 0.001; Cramer’s V = 0.172, p = 0.001); someone to accompany patient (p = 0.002; Cramer’s V = 0.164, p = 0.002); and unaware of screening or lack of perceived health threat (p = 0.019; Cramer’s V = 0.150, p = 0.019). The remaining barriers were not associated with increased likelihood of colonoscopy: fear of finding cancer, belief in screening effectiveness, embarrassment or anxiety, or fear of invasive test. While bowel prep is often cited as a barrier to colonoscopy, this factor was not statistically significant. Likewise, physician-initiated discussion and time off from employment were not associated with screening. The most important colonoscopy barrier was patient knowledge regarding insurance for the procedure; overall, 29% of patients reported that they were unsure if colonoscopy was covered. Among those not screened, the rate rose to 47%. Conclusions: The most important colonoscopy barrier identified was patient knowledge regarding insurance for the procedure. While physician counseling for colonoscopy needs to include bowel prep and procedure risks, greater awareness of insurance coverage and social factors may facilitate physician understanding of colonoscopy screening hesitancy.