Performance of a Shotgun Prediction Model for Colorectal Cancer When Using 16S rRNA Sequencing Data.

Colorectal cancer (CRC), the third most common cancer globally, has shown links to disturbed gut microbiota. While significant efforts have been made to establish a microbial signature indicative of CRC using shotgun metagenomic sequencing, the challenge lies in validating this signature with 16S ribosomal RNA (16S) gene sequencing. The primary obstacle is reconciling the differing outputs of these two methodologies, which often lead to divergent statistical models and conclusions. In this study, we introduce an algorithm designed to bridge this gap by mapping shotgun-derived taxa to their 16S counterparts. This mapping enables us to assess the predictive performance of a shotgun-based microbiome signature using 16S data. Our results demonstrate a reduction in performance when applying the 16S-mapped taxa in the shotgun prediction model, though it retains statistical significance. This suggests that while an exact match between shotgun and 16S data may not yet be feasible, our approach provides a viable method for comparative analysis and validation in the context of CRC-associated microbiome research.

Applicability of the Barcelona scale to assess the quality of cleanliness of mucosa at esophagogastroduodenoscopy.

BACKGROUND AND OBJECTIVES: There are few scales with prospective validation for the assessment of the upper gastrointestinal mucosal cleanliness during an esophagogastroduodenoscopy (EGD). The aim of this study was to develop a valid and reproducible cleanliness scale for use during an EGD. METHODS: We developed a cleanliness scale (Barcelona scale) with a score (0-2 points) of five segments of the upper gastrointestinal tract with thorough cleaning techniques (esophagus, fundus, body, antrum, and duodenum). First, 125 photos (25 of each area) were assessed, and a score was assigned to each image by consensus among 7 experts endoscopists. Subsequently, 100 of the 125 images were selected and the inter- and intra-observer variability of 15 previously trained endoscopists was evaluated using the same images at two different times. RESULTS: In total, 1500 assessments were performed. In 1336/1500 observations (89%) there was agreement with the consensus score, with a mean kappa value of 0.83 (0.45-0.96). In the second evaluation, in 1330/1500 observations (89%) there was agreement with the consensus score, with a mean kappa value of 0.82 (0.45-0.93). The intra-observer variability was 0.89 (0.76-0.99). CONCLUSIONS: The Barcelona cleanliness scale is a valid measure and reproducible with minimal training. Its application in clinical practice is a significant step to standardize the quality of the EGD.

Endoscopy-Related Bleeding and Thromboembolic Events in Patients on Direct Oral Anticoagulants or Vitamin K Antagonists.

BACKGROUND & AIMS: Few prospective studies have assessed the safety of direct oral anticoagulants (DOACs) in elective endoscopy. Our primary aim was to compare the risks of endoscopy-related gastrointestinal bleeding and thromboembolic events in patients on DOACs or vitamin K antagonists (VKAs) in this setting. Secondarily, we examined the impact of the timing of anticoagulant resumption on the risk of delayed bleeding in high-risk therapeutic procedures. METHODS: We conducted a multicenter, prospective, observational study from January 2018 to March 2020 of 1602 patients on oral anticoagulants (1004 on VKAs and 598 on DOACs) undergoing 1874 elective endoscopic procedures. Our primary outcomes were 90-day thromboembolic events and 30-day endoscopy-related gastrointestinal bleeding. The inverse probability of treatment weighting propensity score method was used for baseline covariate adjustment. RESULTS: The 2 groups had similar risks of endoscopy-related gastrointestinal bleeding (VKAs vs DOACs, 6.2% vs 6.7%; adjusted odds ratio [OR], 1.05; 95% CI, 0.67-1.65) and thromboembolic events (VKAs vs DOACs, 1.3% vs 1.5%; adjusted OR, 0.90; 95% CI, 0.34-2.38). In high bleeding risk procedures (n = 747), delayed anticoagulant resumption (> 48 hours or 24-48 hours vs < 24 hours) did not reduce the risk of postprocedural bleeding (10.3%, 9%, and 5.8%, respectively; adjusted P = .43). Hot and cold snare polypectomy were the most frequent high-risk interventions (41.8% and 39.8%, respectively). CONCLUSION: In a prospective study of patients on DOACs or VKAs undergoing elective endoscopy, endoscopy-related bleeding and thromboembolic events showed similar risk. Our study suggests that early anticoagulant resumption is safe in most patients, but more data are needed for advanced high-risk therapeutic procedures.

Diagnosis of Helicobacter pylori Infection by the Arrangement of Collecting Venules Using White Light Endoscopy: Evaluation of Interobserver Agreement.

BACKGROUND: Regular arrangement of collecting venules (RAC) in gastric mucosa accurately identifies patients without Helicobacter pylori (H pylori) infection. The aim of our study was to evaluate the reproducibility of RAC using white light endoscopy without magnification, in a European country, and to assess the impact of proton pump inhibitors (PPIs). METHODS: A multicenter prospective study with image capture of the distal lesser gastric curvature and gastric biopsies was performed. The presence of starfish-like minute points regularly distributed throughout lesser curvature was considered as RAC positive (RAC+). A set of 20 images was used for the training phase and inter and intra-observer agreements were calculated. RESULTS: 174 patients were included and 85 (48.9%) were taking PPIs. Kappa values for interobserver and intra-observer agreements were substantial (0.786) and excellent (0.906), respectively. H. pylori infection was diagnosed in 29 patients (16.7%): 10/85 with PPIs and 19/89 without PPIs (11.8% vs. 21.3%; p = 0.09). All RAC + patients were free of H. pylori infection, with a sensitivity and negative predictive value of 100%, regardless of PPI intake. CONCLUSION: The endoscopic diagnosis of H. pylori by RAC is an easy-to-learn and highly reproducible technique, even with PPI intake. Our results warrant RAC as a real-time diagnostic method for H. pylori-negative infection in Western practice.

Prevalence of missed lesions in patients with inadequate bowel preparation through a very early repeat colonoscopy.

OBJECTIVES: When bowel preparation (BP) is inadequate, international guidelines recommend repeating the colonoscopy within 1 year to avoid missing clinically relevant lesions. We aimed to determine the rate of missed lesions in patients with inadequate BP through a very early repeat colonoscopy with adequate BP. METHODS: Post hoc analysis was conducted using data collected from a prospective multicenter randomized clinical trial including patients with inadequate BP and then repeat colonoscopy. Inadequate BP was defined as the Boston Bowel Preparation Scale (BBPS) score <2 points in any segment. We included patients with any indication for colonoscopy. The adenoma detection rate (ADR), advanced ADR (AADR), and serrated polyp detection rate (SPDR) were calculated for index and repeat colonoscopies. RESULTS: Of the 651 patients with inadequate BP from the original trial, 413 (63.4%) achieved adequate BP on repeat colonoscopy. The median interval between index and repeat colonoscopies was 28 days. On repeat colonoscopy, the ADR was 45.3% (95% confidence interval [CI] 40.5-50.1%), the AADR was 10.9% (95% CI 8.1-14.3%), and the SPDR was 14.3% (95% CI 10.9-17.7%). Cancer was discovered in four patients (1%; 95% CI 0.2-2.5%). A total of 60.2% of all advanced adenoma (AA) were discovered on repeat colonoscopy. A colon segment scored BBPS = 0 had most AA (66.1%) and all four cancers. CONCLUSION: Patients with inadequate BP present a high rate of AAs on repeat colonoscopy. When a colonoscopy has a colon segment score BBPS = 0, we recommend repeating the colonoscopy as soon as possible.

[Referral criteria to clinical genetics from primary care: Consensus document]. / Criterios de derivación a genética clínica desde Atención Primaria. Documento de consenso.

INTRODUCTION: Primary care (PC) is the first contact between the patient and the doctor, so it is essential to be clear about the criteria for suspecting a genetic disease and where it should be referred for study. MATERIAL AND METHODS: Four scientific societies: the Spanish Society of Family and Community Medicine (semFYC), the Spanish Association of Human Genetics (AEGH), the Spanish Association of Pediatrics (AEP) and the Spanish Society of Medical Oncology (SEOM), have reviewed the criteria for referral to the clinical genetics services of the different published guidelines with the purpose of define the recommendations for PC. CONCLUSIONS: With this consensus document, the PC doctor and pediatrician will know when, how and where to refer their patients with hereditary and/or genetic pathology to clinical genetics services.

Polygenic risk score across distinct colorectal cancer screening outcomes: from premalignant polyps to colorectal cancer.

BACKGROUND: Different risk-based colorectal cancer (CRC) screening strategies, such as the use of polygenic risk scores (PRS), have been evaluated to improve effectiveness of these programs. However, few studies have previously assessed its usefulness in a fecal immunochemical test (FIT)-based screening study. METHODS: A PRS of 133 single nucleotide polymorphisms was assessed for 3619 participants: population controls, screening controls, low-risk lesions (LRL), intermediate-risk (IRL), high-risk (HRL), CRC screening program cases, and clinically diagnosed CRC cases. The PRS was compared between the subset of cases (n = 648; IRL+HRL+CRC) and controls (n = 956; controls+LRL) recruited within a FIT-based screening program. Positive predictive values (PPV), negative predictive values (NPV), and the area under the receiver operating characteristic curve (aROC) were estimated using cross-validation. RESULTS: The overall PRS range was 110-156. PRS values increased along the CRC tumorigenesis pathway (Mann-Kendall P value 0.007). Within the screening subset, the PRS ranged 110-151 and was associated with higher risk-lesions and CRC risk (ORD10vsD1 1.92, 95% CI 1.22-3.03). The cross-validated aROC of the PRS for cases and controls was 0.56 (95% CI 0.53-0.59). Discrimination was equal when restricted to positive FIT (aROC 0.56), but lower among negative FIT (aROC 0.55). The overall PPV among positive FIT was 0.48. PPV were dependent on the number of risk alleles for positive FIT (PPVp10-p90 0.48-0.57). CONCLUSIONS: PRS plays an important role along the CRC tumorigenesis pathway; however, in practice, its utility to stratify the general population or as a second test after a FIT positive result is still doubtful. Currently, PRS is not able to safely stratify the general population since the improvement on PPV values is scarce.

Educational nurse-led telephone intervention shortly before colonoscopy as a salvage strategy after previous bowel preparation failure: a multicenter randomized trial.

BACKGROUND: The most important predictor of unsuccessful bowel preparation is previous failure. For those patients with previous failure, we hypothesized that a nurse-led educational intervention by telephone shortly before the colonoscopy appointment could improve cleansing efficacy. METHODS: We performed a multicenter, endoscopist-blinded, randomized controlled trial. Consecutive outpatients with previous inadequate bowel preparation were enrolled. Both groups received the same standard bowel preparation protocol. The intervention group also received reinforced education by telephone within 48 hours before the colonoscopy. The primary outcome was effective bowel preparation according to the Boston Bowel Preparation Scale. Intention-to-treat (ITT) analysis included all randomized patients. Per-protocol analysis included patients who could be contacted by telephone and the control cases. RESULTS: 657 participants were recruited by 11 Spanish hospitals. In the ITT analysis, there was no significant difference between the intervention and control groups in the rate of successful bowel preparation (77.3 % vs. 72 %; P = 0.12). In the intervention group, 267 patients (82.9 %) were contacted by telephone. Per-protocol analysis revealed significantly improved bowel preparation in the intervention group (83.5 % vs. 72.0 %; P = 0.001). CONCLUSION: Among all patients with previous inadequate bowel preparation, nurse-led telephone education did not result in a significant improvement in bowel cleansing. However, in the 83 % of patients who could be contacted, bowel preparation was substantially improved. Phone education may therefore be a useful tool for improving the quality of bowel preparation in those cases.

Polyp fingerprint: automatic recognition of colorectal polyps' unique features.

BACKGROUND: Content-based image retrieval (CBIR) is an application of machine learning used to retrieve images by similarity on the basis of features. Our objective was to develop a CBIR system that could identify images containing the same polyp ('polyp fingerprint'). METHODS: A machine learning technique called Bag of Words was used to describe each endoscopic image containing a polyp in a unique way. The system was tested with 243 white light images belonging to 99 different polyps (for each polyp there were at least two images representing it in two different temporal moments). Images were acquired in routine colonoscopies at Hospital Clínic using high-definition Olympus endoscopes. The method provided for each image the closest match within the dataset. RESULTS: The system matched another image of the same polyp in 221/243 cases (91%). No differences were observed in the number of correct matches according to Paris classification (protruded: 90.7% vs. non-protruded: 91.3%) and size (< 10 mm: 91.6% vs. > 10 mm: 90%). CONCLUSIONS: A CBIR system can match accurately two images containing the same polyp, which could be a helpful aid for polyp image recognition.

Review of computational methods for the detection and classification of polyps in colonoscopy imaging. / Revisión de métodos computacionales de detección y clasificación de pólipos en imagen de colonoscopia.

Computer-aided diagnosis (CAD) is a tool with great potential to help endoscopists in the tasks of detecting and histologically classifying colorectal polyps. In recent years, different technologies have been described and their potential utility has been increasingly evidenced, which has generated great expectations among scientific societies. However, most of these works are retrospective and use images of different quality and characteristics which are analysed off line. This review aims to familiarise gastroenterologists with computational methods and the particularities of endoscopic imaging, which have an impact on image processing analysis. Finally, the publicly available image databases, needed to compare and confirm the results obtained with different methods, are presented.

Advanced endoscopy technologies to improve the detection and characterisation of colorrectal polyps. / Tecnologías de endoscopia avanzada para mejorar la detección y caracterización de los pólipos colorrectales.

Colorectal cancer is a major health problem. An improvement to its survival has been demonstrated by performing colonoscopy screenings and removing its precursor lesions: polyps. However, colonoscopy is not infallible and multiple strategies have been proposed aimed at improving the quality thereof. This report describes the endoscopic systems available to improve the detection and characterization of polyps, the different classifications for histological prediction and the current indications of advanced endoscopic diagnostic techniques.

Evaluation of long-term adherence to oesophagogastroduodenoscopy quality indicators. / Evaluación del cumplimiento a largo plazo de los indicadores de calidad en la esofagogastroduodenoscopia.

INTRODUCTION: In a previous study we demonstrated that a simple training programme improved quality indicators of Oesophagogastroduodenoscopy (OGD) achieving the recommended benchmarks. However, the long-term effect of this intervention is unknown. The aim of this study was to assess the quality of OGDs performed 3 years after of having completed a training programme. MATERIAL AND METHODS: A comparative study of 2 cohorts was designed as follows: Group A included OGDs performed in 2016 promptly after a training programme and Group B with OGDs performed from January to March 2019, this group was also divided into 2 subgroups: subgroup B1 of Endoscopists who had participated in the previous training programme and subgroup B2 of Endoscopists who had not. The intra-procedure quality indicators proposed by ASGE-ACG were used. RESULTS: A total of 1236 OGDs were analysed, 600 from Group A and 636 from Group B (439 subgroup B1 and 197 subgroup B2). The number of complete examinations was lower in Group B (566 [94.3%] vs. 551 [86.6%]; p<0.001). A significant decrease was observed in nearly all quality indicators and they did not reach the recommended benchmarks: retroflexion in the stomach (96% vs. 81%; p<0.001); Seattle biopsy protocol (86% vs. 50%; p=0.03), description of the upper GI bleeding lesion (100% vs. 62%; p<0.01), sufficient intestinal biopsy specimens (at least 4) in suspected coeliac disease (92.5% vs. 18%; p<0.001), photo documentation of the lesion (94% vs. 90%; p<0.05). Regarding the overall assessment of the procedure (including correct performance and adequate photo documentation), a significant decrease was also observed (90.5% vs. 62%; p<0.001). There were no differences between subgroups B1 and B2. CONCLUSIONS: The improvement observed in 2016 after a training programme did not prevail after 3 years. In order to keep the quality of OGDs above the recommended benchmarks, it is necessary to implement continuous training programmes.

Association between a regular arrangement of collecting venules and absence of Helicobacter pylori infection in a European population.

BACKGROUND AND AIMS: Helicobacter pylori is the major cause of gastritis and gastritis-associated diseases. Detection of a regular arrangement of collecting venules (RAC) in the lesser gastric curvature correlates with negative H pylori status with a sensitivity and negative predictive value (NPV) higher than 90% in Asian countries. The aim of the study was to evaluate the value of RAC as a diagnostic method of H pylori infection in a European population. METHODS: A prospective study with high-definition endoscopes without magnification was performed by 3 endoscopists. The presence of starfish-like minute points regularly distributed throughout the lesser curvature of the gastric body was considered RAC positive (RAC+). Gastric biopsies were performed during the procedure for H pylori diagnosis. RESULTS: One hundred forty patients were included from February 2017 to May 2018. The prevalence of H pylori infection was 31% and 47 of 140 patients (34%) were RAC+; 13 of 23 patients in whom H pylori was eradicated were RAC+. The mean age of RAC+ patients was lower (44.4 vs 52.4 years, P = .004) and they had less- significant endoscopic findings (9; 19.1% vs 38; 80.9%; P = .017). Gender, use of nonsteroidal anti-inflammatory drugs, antithrombotic or anticoagulants treatments, and a history of H pylori eradication did not show differences in the RAC pattern. The absence of RAC was associated with H pylori infection in 47.3% (44/93) of cases. In contrast, all RAC+ patients were free of H pylori infection, with sensitivity and NPV of 100% for the exclusion of H pylori infection. CONCLUSION: The presence of RAC+ in the lesser curvature evaluated with high-definition endoscopy can accurately identify patients without H pylori.

Computer-aided prediction of polyp histology on white light colonoscopy using surface pattern analysis.

BACKGROUND: This study aimed to evaluate a new computational histology prediction system based on colorectal polyp textural surface patterns using high definition white light images. METHODS: Textural elements (textons) were characterized according to their contrast with respect to the surface, shape, and number of bifurcations, assuming that dysplastic polyps are associated with highly contrasted, large tubular patterns with some degree of bifurcation. Computer-aided diagnosis (CAD) was compared with pathological diagnosis and the diagnosis made by endoscopists using Kudo and Narrow-Band Imaging International Colorectal Endoscopic classifications. RESULTS: Images of 225 polyps were evaluated (142 dysplastic and 83 nondysplastic). The CAD system correctly classified 205 polyps (91.1 %): 131/142 dysplastic (92.3 %) and 74/83 (89.2 %) nondysplastic. For the subgroup of 100 diminutive polyps (≤ 5 mm), CAD correctly classified 87 polyps (87.0 %): 43/50 (86.0 %) dysplastic and 44/50 (88.0 %) nondysplastic. There were no statistically significant differences in polyp histology prediction between the CAD system and endoscopist assessment. CONCLUSION: A computer vision system based on the characterization of the polyp surface in white light accurately predicted colorectal polyp histology.

State of endoscopic ultrasonography in Spain in 2017. / Estado de la ecoendoscopia en España en 2017.

AIM: To understand the current state of endoscopic ultrasonography (EUS) in Spain. METHODS: Descriptive analysis from a national survey with 11 questions: 10 related to technique and 1 to the training and experience of the endoscopists. RESULTS: Sixty endoscopists from 48 of the 97 (49.5%) hospitals that perform EUS in Spain responded to the survey. A total of 28,678 procedures (20,311 diagnostic, 7,446 with puncture and 921 therapeutic) were recorded over the course of one year. Approximately 64% of the hospitals perform between 300 and 999 tests per year. All have radial and sectorial echoendoscopes, with a median of 2 (2-8) scopes. For cytological diagnosis, the 22-gauge needle is the most commonly used (98%) and, for histological diagnosis, the Procore (72%). The study of the pancreas and bile duct is the most common indication for diagnostic EUS (60%), followed by the staging of digestive tract neoplasms (20%). Approximately 72% of the hospitals perform on-site cytopathology evaluations and sedation is administered in equal parts by both endoscopists and anaesthetists. In terms of experience, 45% of echoendoscopists perform fewer than 300 annual exams and the median training duration is 6months (0.5-36). CONCLUSIONS: EUS is adequately implemented in Spain and good equipment is available. However, it is necessary to establish a standardised EUS training program since the one undertaken by many echoendoscopists could prove insufficient according to the standards established by Scientific Societies.

Eating disorder symptoms and weight pressure in female rowers: associations between self-concept, psychological well-being and body composition.

BACKGROUND: Female rowers may be at risk of eating disorders and high weight pressure. AIM: The purpose of the study was to investigate the prevalence of disordered eating symptoms and weight-related pressure and the associations with self-concept, psychological well-being, socio-demographic data, experience, performance level and body composition in female fixed-bench rowers. METHODS: Female rowers (n = 208; age ranged mean ± SD 23.6 ± 6.5 years) completed the SCOFF scale, Weight-Pressures in Sport-Females (WPS-F), Physical Self-Concept Questionnaire and the Ryff scales of psychological well-being and provided information on their experience and level of competition. In a subgroup of 115 athletes, body composition was assessed using bioimpedance. RESULTS: It was found that 42.3% of the athletes scored ≥ 2 on SCOFF and mean ± SD value of WPS-F score was 3.65 ± 0.82. Stepwise regression analysis revealed that self-concept of strength and pressure from teammates and the uniform were associated with higher ED symptoms, whereas better psychological well-being in terms of autonomy, self-concept of attractiveness, and age were protective factors for ED symptoms. BMI, athletes' physical condition, strength, and experience were associated with more weight-related pressure and better self-concept of attractiveness and physical well-being of autonomy were significantly associated with less pressure. In body composition analysis, higher extra cellular water, self-acceptance, and physical condition were associated with more weight-related pressure in female rowers, being attractiveness and the environmental mastery protective elements. CONCLUSIONS: The prevalence of ED symptomatology and weight-related pressure are high in female fixed bench rowing. The psychological factors of well-being and self-concept, team environment, body image concerns and body composition analysis should be considered to promote healthy eating behaviours in female rowers.

Athletes may be at increased risk of developing disordered eating behaviours that, if persistent, may lead to a diagnosis of an eating disorder. This can affect their health in the short and long term. The risk factors are many, and perceived weight-related pressures and psychological attitudes towards body image, appearance and concerns are less well understood. Female rowers are at high risk for eating disorder symptoms, and athletes' self-concept of strength and pressure from teammates and the uniform were associated as negative factors for eating disorder symptoms. On the other hand, better psychological well-being in terms of autonomy, self-concept of attractiveness and age were protective factors for eating disorder symptoms. Weight pressure was associated with higher body mass index, water retention, physical condition, strength and experience, whereas better self-concept of attractiveness and physical well-being were significantly associated with less pressure. Weight pressure and psychological attitudes towards body image have the role of protective/facilitating factors against the development of eating disorders. They should be taken into account when designing prevention and intervention programmes for athletes, coaches, parents and technical staff.

In vivo computer-aided diagnosis of colorectal polyps using white light endoscopy.

Background and study aims Artificial intelligence is currently able to accurately predict the histology of colorectal polyps. However, systems developed to date use complex optical technologies and have not been tested in vivo. The objective of this study was to evaluate the efficacy of a new deep learning-based optical diagnosis system, ATENEA, in a real clinical setting using only high-definition white light endoscopy (WLE) and to compare its performance with endoscopists. Methods ATENEA was prospectively tested in real life on consecutive polyps detected in colorectal cancer screening colonoscopies at Hospital Clínic. No images were discarded, and only WLE was used. The in vivo ATENEA's prediction (adenoma vs non-adenoma) was compared with the prediction of four staff endoscopists without specific training in optical diagnosis for the study purposes. Endoscopists were blind to the ATENEA output. Histology was the gold standard. Results Ninety polyps (median size: 5 mm, range: 2-25) from 31 patients were included of which 69 (76.7 %) were adenomas. ATENEA correctly predicted the histology in 63 of 69 (91.3 %, 95 % CI: 82 %-97 %) adenomas and 12 of 21 (57.1 %, 95 % CI: 34 %-78 %) non-adenomas while endoscopists made correct predictions in 52 of 69 (75.4 %, 95 % CI: 60 %-85 %) and 20 of 21 (95.2 %, 95 % CI: 76 %-100 %), respectively. The global accuracy was 83.3 % (95 % CI: 74%-90 %) and 80 % (95 % CI: 70 %-88 %) for ATENEA and endoscopists, respectively. Conclusion ATENEA can accurately be used for in vivo characterization of colorectal polyps, enabling the endoscopist to make direct decisions. ATENEA showed a global accuracy similar to that of endoscopists despite an unsatisfactory performance for non-adenomatous lesions.