Maria Lopez-Ceron

Aims Currently, the risk factors that determine presence of active bleeding in the context of delayed postpolypectomy hemorrhage (DPPB) remain unknown and therefore the need for urgent endoscopic treatment. The objective is to determine risk factors associated with active bleeding in DPPB to identify those who could benefit from endoscopic therapy. Methods Unicentric retrospective study that includes all patients who presented DPPB in the period 01/2019- 07/2022 in a Spanish center. DPPB was defined as any bleeding after polypectomy that required urgent care within 30 days after the procedure. Data were analyzed with SPPS (version 25). Results We found 105 cases of DPPB. 62,85% male (mean age 65,6). In 21,90% (23/105) the eschar had completely closed after resection. 67,61% (71/105) required urgent colonoscopy of which 20,95% (22/105) presented active bleeding and 25,71% (27/105) had stigmata of recent bleeding. Endoscopic therapy was performed in 77,46% (55/71). In the univariate analysis: Right colon location (P 0.019), size >2 cm (P 0.04) and a GSEED RE2 score ≥ 6 (P 0.02) were shown to be risk factors associated with active bleeding. However, the GSEED RE2 score ≥ 6 points was the only one shown to be an independent risk factor in the multivariate analysis (19; 1.6-24 P: 0.02). The prophylactic closure of the eschar did not behave as a protective factor. Conclusions Patients with high risk GSEED RE2 score (≥ 6 points) have higher probability of active DPPB, therefore this tool could be useful as a method for prioritizing this endoscopic urgency. Article published online: 14 April 2023 © 2023. European Society of Gastrointestinal Endoscopy. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

Aims To determine algorithms for choosing the suitable treatment in non-pedunculated colorectal lesions ≥20 mm assessed by Western endoscopists with NBI and without magnification.​​​​ Methods Observational prospective multicenter study conducted at 17 academic and community hospitals by 58 endoscopists. Unbiased conditional inference trees (CTREE) were fitted to analyze the association between the appropriate treatment based on the histology (surgery, en bloc resection or piecemeal EMR) based on the endoscopic characteristics of the lesions. Results 542 lesions from 517 patients were included in the analysis. The most important lesion characteristic for choosing piecemeal EMR was the absence of ulceration (p 20 MM ACCORDING TO WESTERN AND EASTERN APPROACH: CONDITIONAL INFERENCE-TREE FROM A PROSPECTIVE MULTICENTER COHORT. Endoscopy 2021; 53: S88. Publication Date: 19 March 2021 (online) © 2021. European Society of Gastrointestinal Endoscopy. All rights reserved. Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, Germany

POLE and POLD1 screening in 155 patients with multiple polyps and early-onset colorectal cancer

Background and study aims: Serrated polyposis syndrome (SPS) is a high risk condition for colorectal cancer (CRC). Surveillance strategies for patients with serrated lesions remain controversial. We aimed to evaluate a diagnostic strategy to detect SPS consistently during reassessment colonoscopy in patients with proximal serrated lesions. Methods: This was a retrospective study of all individuals from a fecal immunochemical test (FIT)-based CRC screening program (2010 – 2013) with one or more serrated lesions of ≥ 5 mm proximal to the sigmoid colon on baseline colonoscopy. We analyzed all individuals empirically scheduled for a reassessment colonoscopy aimed at diagnosing SPS within 1 year. Reassessment colonoscopy was performed with standard white-light or chromoendoscopy ± high definition endoscopy depending on availability. SPS diagnosis was based on the cumulative number of polyps in both the baseline and reassessment colonoscopies. Factors associated with SPS diagnosis were analyzed. Results: From 3444 screening colonoscopies, 196 patients met the study entry criteria, of whom 11 patients (0.32 %) met the criteria for SPS on baseline colonoscopy. Reassessment colonoscopies were performed in 71 patients at 11.9 ± 1.7 months and detected 20 additional patients with SPS, a tripling of the rate of SPS up to 0.90 %. Independent factors associated with SPS diagnosis were: having five or more proximal serrated lesions (odds ratio [OR] 4.01 [95 % confidence interval 1.20 – 13.45]; P = 0.02) or two or more sessile serrated polyps ≥ 10 mm (OR 6.35 [1.40 – 28.81]; P = 0.02) on baseline colonoscopy and the use of chromoendoscopy ± high definition endoscopy during reassessment colonoscopy (OR 4.99 [1.11 – 22.36]; P = 0.04). Conclusions: A 1-year reassessment colonoscopy using chromoendoscopy and high definition endoscopes substantially improves SPS detection in individuals from a FIT-based screening program with proximal serrated lesions. Five or more proximal serrated lesions or two or more sessile serrated polyps ≥ 10 mm could be thresholds for requiring a reassessment colonoscopy. Prospective studies are required to validate these results and adjust surveillance recommendations in patients with serrated lesions. ^* These authors share senior authorship.

Objective Outside clinical trials, the effectiveness of chromoendoscopy (CE) for long-standing IBD surveillance is controversial. We aimed to assess the effectiveness of CE for neoplasia detection and characterisation, in real-life. Design From June 2012 to 2014, patients with IBD were prospectively included in a multicentre cohort study. Each colonic segment was evaluated with white light followed by 0.4% indigo carmine CE. Specific lesions' features were recorded. Optical diagnosis was assessed. Dysplasia detection rate between expert and non-expert endoscopists and learning curve were ascertained. Results Ninety-four (15.7%) dysplastic (1 cancer, 5 high-grade dysplasia, 88 low-grade dysplasia) and 503 (84.3%) non-dysplastic lesions were detected in 350 patients (47% female; mean disease duration: 17 years). Colonoscopies were performed with standard definition (41.5%) or high definition (58.5%). Dysplasia miss rate with white light was 40/94 (57.4% incremental yield for CE). CE-incremental detection yield for dysplasia was comparable between standard definition and high definition (51.5% vs 52.3%, p=0.30). Dysplasia detection rate was comparable between expert and non-expert (18.5% vs 13.1%, p=0.20). No significant learning curve was observed (8.2% vs 14.2%, p=0.46). Sensitivity, specificity, and positive and negative predictive values for dysplasia optical diagnosis were 70%, 90%, 58% and 94%, respectively. Endoscopic characteristics predictive of dysplasia were: proximal location, loss of innominate lines, polypoid morphology and Kudo pit pattern III–V. Conclusions CE presents a high diagnostic yield for neoplasia detection, irrespectively of the technology and experience available in any centre. In vivo, CE optical diagnosis is highly accurate for ruling out dysplasia, especially in expert hands. Lesion characteristics can aid the endoscopist for in situ therapeutic decisions. Trial registration number NCT02543762.

Background Colorectal cancer (CRC) screening programs result in the detection of early-stage asymptomatic carcinomas suitable to be surgically cured. Lymph nodes (LN) from early CRC are usually small and may be difficult to collect. Still, at least 12 LNs should be analyzed from colectomies, to ensure a reliable pN0 stage. Presurgical endoscopic tattooing improves LN procurement. In addition, molecular detection of occult LN tumor burden in histologically pN0 CRC patients is associated with a decreased survival rate. We aimed to study the impact of presurgical endoscopic tattooing on the molecular detection of LN tumor burden in early colon neoplasms. Methods A prospective cohort study from a CRC screening-based population was performed at a tertiary academic hospital. LNs from colectomies with and without preoperative endoscopic tattooing were assessed by two methods, hematoxylin and eosin (HE), and RT-LAMP, to detect tumor cytokeratin 19 (CK19) mRNA. We compared the amount of tumor burden and LN yields from tattooed and non-tattooed specimens. Results HE and RT-LAMP analyses of 936 LNs were performed from 71 colectomies containing early carcinomas and endoscopically unresectable adenomas (8 pT0, 17 pTis, 27 pT1, 19 pT2); 47 out of 71 (66.2 %) were tattooed. Molecular positivity correlated with the presence of tattoo in LN [p < 0.001; OR 3.1 (95 % CI 1.7–5.5)]. A significantly higher number of LNs were obtained in tattooed specimens (median 17 LN vs. 14.5 LN; p = 0.019). Conclusions Endoscopic tattooing enables the analysis of those LNs most prone to harbor tumor cells and improves the number of LN harvested.

Background and aims: Polyp miss-rate is a drawback of colonoscopy that increases significantly for small polyps. We explored the efficacy of an automatic computer-vision method for polyp detection. Methods: Our method relies on a model that defines polyp boundaries as valleys of image intensity. Valley information is integrated into energy maps that represent the likelihood of the presence of a polyp. Results: In 24 videos containing polyps from routine colonoscopies, all polyps were detected in at least one frame. The mean of the maximum values on the energy map was higher for frames with polyps than without (P < 0.001). Performance improved in high quality frames (AUC = 0.79 [95 %CI 0.70 – 0.87] vs. 0.75 [95 %CI 0.66 – 0.83]). With 3.75 set as the maximum threshold value, sensitivity and specificity for the detection of polyps were 70.4 % (95 %CI 60.3 % – 80.8 %) and 72.4 % (95 %CI 61.6 % – 84.6 %), respectively. Conclusion: Energy maps performed well for colonic polyp detection, indicating their potential applicability in clinical practice.

Colorectal cancer (CRC) is one of the most common neoplasms in the world. Fanconi anemia (FA) is a very rare genetic disease causing bone marrow failure, congenital growth abnormalities and cancer predisposition. The comprehensive FA DNA damage repair pathway requires the collaboration of 53 proteins and it is necessary to restore genome integrity by efficiently repairing damaged DNA. A link between FA genes in breast and ovarian cancer germline predisposition has been previously suggested. We selected 74 CRC patients from 40 unrelated Spanish families with strong CRC aggregation compatible with an autosomal dominant pattern of inheritance and without mutations in known hereditary CRC genes and performed germline DNA whole-exome sequencing with the aim of finding new candidate germline predisposition variants. After sequencing and data analysis, variant prioritization selected only those very rare alterations, producing a putative loss of function and located in genes with a role compatible with cancer. We detected an enrichment for variants in FA DNA damage repair pathway genes in our familial CRC cohort as 6 families carried heterozygous, rare, potentially pathogenic variants located in BRCA2/FANCD1, BRIP1/FANCJ, FANCC, FANCE and REV3L/POLZ. In conclusion, the FA DNA damage repair pathway may play an important role in the inherited predisposition to CRC.