Colonic Location Research Articles

Conversion therapy with the intent to perform radical local treatment may not be suitable for patients with 10 or more liver metastases from colorectal cancer.

The number of colorectal cancer liver metastases (CRLMs) is usually considered a contradictory indicator to surgical resection. However, some patients with initially unresectable CRLMs can receive radical local treatment after conversion therapy. This study aimed to evaluate the effect of radical local treatment after conversion therapy and the prognosis of patients with more than 10 initially unresectable CRLMs. Data for a total of 229 patients with initially unresectable CRLMs were retrospectively reviewed between December 2012 and January 2020. Among these patients, 107 had ≥10 CRLMs, and 122 had <10 CRLMs. Overall survival (OS) and progression-free survival (PFS) were used to reflect the prognosis of different groups of patients. Conversion therapy was defined as an initially unresectable liver metastasis converted into an R0 resectable lesion after systemic chemotherapy. Radical local treatment included hepatectomy and radiofrequency ablation (RFA). Patients with ≥10 CRLMs had a lower conversion rate (42.7% vs. 56.6%, p=0.001). Baseline clinical N stage 1-2, ≥8 first-line chemotherapy courses, and stable disease (SD) according to the Response Evaluation Criteria in Solid Tumours (RECIST) were independent factors predictive of conversion failure. Primary tumour location in the right colon, RECIST response of SD, and the absence of targeted therapy were independent factors predictive of unfavourable OS. The survival curves revealed that the OS of patients with or without conversion could be distinguished only among patients with <10 CRLMs (89.9% [95% CI, 82.5%-98.0%] vs. 58.9% [95% CI, 45.2%-76.7%], p < 0.001); this cut-off point could also distinguish patients with a successful conversion outcome according to OS (89.9% [95% CI, 82.5-98.0%] vs. 58.2% [95% CI, 42.2-80.4%], p=0.008). For CRLMs ≥ 10, patients with a successful conversion outcome cannot be distinguished from those without successful conversion outcome according to OS. Thus, conversion therapy with the intent to perform radical local treatment may not be suitable for patients with 10 or more liver metastases from colorectal cancer.

Tumor-associated CD3- and CD8-positive immune cells in colorectal cancer: The additional prognostic value of CD8+-to-CD3+ ratio remains debatable.

A large number of infiltrating CD3- and CD8-positive inflammatory cells indicates an improved survival in colorectal cancer (CRC), similar to many other cancers. We investigated the prognostic value of different combinations of CD3- and CD8-positive immune cells in CRC patients. The densities of CD3- and CD8-positive cells in intratumoral and stromal tissues were evaluated from 539 patients, for which we calculated a CD3 tumor-stroma index, a CD8 tumor-stroma index, and a CD3-CD8 tumor-stroma index. High CD3 and CD8 tumor-stroma indices associated with stage I to II disease (p < 0.001 for both). The CD3 tumor-stroma index associated with a colonic tumor location (p = 0.006), while the CD8 tumor-stroma index associated with right-sided tumors (p < 0.001) and histological grade 3 tumors (p = 0.032). High intratumoral and stromal densities for CD3- and CD8-positive immune cells, the CD3 tumor-stroma index, the CD8 tumor-stroma index, and the CD3-CD8 tumor-stroma index all indicated a better DSS. The CD3 tumor-stroma index carries a strong prognostic value in CRC, and none of the CD3 and CD8 combinations we analyzed proved superior.

Colonic diverticulitis location is a risk factor for recurrence: a multicenter, retrospective cohort study in Asian patients

Evidence regarding the recurrence of diverticulitis is limited in Asian patients. This study aims to investigate recurrence rates and identify predictive factors for the recurrence of diverticulitis following successful nonoperative treatment in Asian patients. A multicenter, retrospective cohort study was conducted between 2012 and 2018. Adult patients with computed tomography (CT)-proven colonic diverticulitis were included. The primary outcome was the recurrence of diverticulitis, which was defined as another episode of occurrence of the infection after index hospital stay. Cumulative recurrence rates were calculated using the Kaplan–Meier method. Cox regression models were employed to identify parameters that significantly and independently predicted recurrence. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated. A total of 929 patients were included. Diverticulitis in the cecum/ascending occurred in 675 (72.6%) patients. The average follow-up period was 651 days. Recurrence was observed in 115 (12.4%) patients and most significantly observed in patients with sigmoid diverticulitis (HR, 2.24; 95% CIs 1.59–3.97), followed by those with descending colon diverticulitis (HR, 1.92; 95% CIs 1.17–3.25). Although most of the Asian patients had right-sided colonic diverticulitis, those with sigmoid diverticulitis had the highest risk of recurrence.

Tumour budding in colorectal carcinoma: Association with other histopathological prognostic parameters

Colorectal carcinoma (CRC) is the third leading cancer in India. Pathologists play a crucial role in assessing stage, analyzing surgical margins and documenting the histopathologic prognostic parameters. Tumour budding is one such prognostic parameter, defined as single cells or small groups of tumour cells (up to 4 cell clusters) at the invasive front of the tumour. The aim of this study is to examine the association of tumour budding with other histopathological prognostic parameters in patients with colorectal carcinoma.TheHematoxylin &amp; Eosin (H &amp;E) stained slides of 52 histopathologically diagnosed CRC resection specimens were reviewed and tumour budding (BD) was assessed into four grades under 200x power. Other histopathological prognostic parameters like tumour size, site, grade, laterality, lymphovascular invasion, perineural invasion, T and N stage were analyzed using descriptive statistics and Chi-square test with Software SPSS version 23.A higher BD score is seen to be more often associated with grade 3 tumour morphology, presence of perineural invasion, tumour size of 5cm or more and tumours located in the sigmoid colon or rectum. No association of tumour budding is seen with TIL’s or tumour of size &amp;#60; 5cm.Tumour budding is a practical and significant histological index for identification of high malignant potential and poor outcome in CRC patients with rectal or sigmoid colon location, size more than 5cm, perineural invasion and higher histological grade. Tumour budding may help identify patients who need a more intensive postoperative follow up and the possibility of adjuvant therapy.

Clip or Tattooing: A Comparative Study for Preoperative Colon Cancer Endoscopic Localization.

Background and AimPreoperative endoscopic markers have been extensively used for the localization of colonic neoplastic lesions in laparoscopic surgery. We conducted this respective cohort study to compare the localization accuracy of two commonly used endoscopic marker strategies (endoscopic clip plus abdominal plain film and endoscopic tattooing).MethodsPatients who received preoperative colonoscopy localization for colonic neoplasia and underwent an elective laparoscopic operation afterward between 2013 and 2020 were included in this retrospective study. The localization accuracy of the two endoscopic strategies was compared, and the predictors of successful endoscopic localization were identified by multivariate regression.ResultsIn total, 195 patients [average age 62.4 ± 9.2 years, 123 male (63.1%)] undergoing preoperative colonoscopy localization and subsequent laparoscopic colectomy for colonic neoplasms were included. Endoscopic localization was finally proven to be successful in 150 (76.9%) patients in the surgery. Compared to the tattooing group, patients who had successful localization for colonic lesions were fewer in the clip group (64 of 101 cases, 63.4% vs. 86 of 94 cases, 91.5%, p < 0.001). The multivariate regression analysis showed that the endoscopic tattooing strategy, endoscopic clip strategy, and lesion location were all predictors for successful localization (all with p < 0.001).ConclusionCompared with endoscopic clip plus abdominal plain film, endoscopic tattooing had higher localization accuracy and less intraoperative colonoscopy counseling; the endoscopic clip strategy, tattooing strategy, and colonic lesion location were all predictors of successful endoscopic localization.

Ischemic colitis. Does right colon location mean worst prognosis?

IntroductionMost patients with ischemic colitis have a favourable evolution; nevertheless, the location in the right colon has been associated with a worse prognosis. The purpose of this study is to compare the clinical presentation and results of right colon ischemic colitis (CICD) with ischemic colitis of other colonic segments (non-CIDC). MethodsRetrospective, observational study of patients admitted to our hospital with ischemic colitis between 1993 and 2014, identified through a computerized search of ICD9 codes. They were divided into 2 groups: CICD and non-CICD. Comorbidities, clinical presentation, need for surgery, and mortality were compared. Multivariate analysis was performed using logistic regression adjusting for age and sex. Statistical significance was established at a value of P < 0.05. ResultsA total of 204 patients were identified, 61 (30%) with CICD; 61% of CICD patients required surgery compared to 22% of non-CICD patients (P < 0.001). Differences in post-surgical mortality (32% vs 55%) and overall mortality (20% vs 15%) were not statistically significant. CICD patients had more commonly unfavourable outcomes than non-CICD patients (61% vs 25%, P < 0.001). The odds ratio (OR) for surgery was 5.28 and 4.47 for unfavourable outcomes for patients with CICD. ConclusionsCICD patients have a worse prognosis than non-CICD patients, 5 times more likely to need surgery and 4 times more likely to have unfavourable outcomes.

P627 Variables associated with evolution to moderate to severe Crohn’s disease at two reference centers in Salvador, Bahia, Brazil

Abstract Background The identification of variables associated with evolution to moderate to severe disease is essential for the therapeutic management of patients with Crohn’s disease (CD). However, studies on this topic are scarce in developing countries. The main objective of this study is to determine the variables associated with hospitalization in patients with CD. The secondary objective is to identify variables associated with surgery, intestinal resection, rehospitalization, surgical recurrence and use of immunobiological therapy. Methods Cross-sectional study with a retrospective component that involved two reference centers for inflammatory bowel diseases in the public health system. Data were collected through a specific questionnaire and review of medical records in the period 2019 to 2021. The association between variables was evaluated through Chi-Square test and multivariate binary logistic regression. Results Were included 220 patients, 50.9% female. The most common findings were: age at diagnosis between 17 and 40 years (67.7%), colonic location (45.0%) and no stricturing no penetrating behavior (75.9%). Perianal disease was observed in 27.7% and involvement of the upper gastrointestinal (GI) in 16.1% (Table 1). 174 (79.1%) patients were hospitalized, 109 (49.5%) underwent surgery, being 50 (22.7%) bowel resection. 106 (60.9%) were readmitted, 13 (26.0%) presented surgical recurrence and 128 (58.2%) used immunobiologicals. Perianal disease was the only variable associated with hospitalization (p=0.012). Stricturing or penetrating behavior (p&amp;lt;0.001) and perianal disease (p&amp;lt;0.001) were associated with surgery. Regarding intestinal resection, ileal or ileocolon location (p=0.044) and stricturing or penetrating behavior (p&amp;lt;0.001) were variables associated. The use of corticosteroids in the first flare (p&amp;lt;0.001) was associated with rehospitalization, and postoperative complications (p=0.029) with surgical recurrence. Age at diagnosis below 40 years (p=0.004), upper GI involvement (p=0.040) and perianal disease (p&amp;lt;0.001) were associated with the use of immunobiologicals (Table 2). Conclusion This is a pioneer study in Brazil on variables associated with evolution to moderate to severe CD. Perianal disease and stricturing or penetrating behavior were associated with more than one outcome. Age at diagnosis below 40 years, ileal and ileo-colic location, upper GI involvement, use of corticosteroids in the first flare and postoperative complications were also variables found. These data are similar to those found in countries with a high prevalence of the disease1. Reference 1. Torres J et al. Predicting Outcomes to Optimize Disease Management in Inflammatory Bowel Diseases. J Crohns Colitis. 2016;10(12):1385–1394.

P692 Clinical, therapeutic and evolutionary profile of fistulizing ano-perineal lesions in Crohn’s disease

Abstract Background Ano-perineal lesions (APLs) during Crohn’s disease (CD) are frequent and varied. Ano-perineal fistulas (APF) are the most common and severe manifestations. They are associated with increased morbidity and considerable impairment of quality of life. Their management is not always easy despite therapeutic advances, particularly anti-TNFα.The aim of our work was to describe the epidemiological profile, the therapeutic modalities and the evolutionary aspects of APF during CD. Methods This was a retrospective, descriptive, single-center study collecting records of patients followed for CD with APF between January 2010 and December 2020. The patients had a proctological examination and a perineal MRI. We recorded clinical, endoscopic, radiological data, therapeutic management and clinical response to the initial therapeutic regimen. Complete remission was defined as closure of all initially productive fistulas, partial response was defined as closure of more than 50% of fistulas. Therapeutic failure was defined as closure of less than 50% of the initially productive fistulas. Results 83 patients followed up for CD with APLs were collated of which 38 had APF (45.7%). The mean age was 42 years [26 - 73] with a sex ratio of 0.4. Active smoking was noted in six patients (15.8%). In 55.3% of cases, PAF was present at the time of diagnosis of CD (n=21).17 patients had developed one or more PAFs during the course of their disease with a mean delay of seven years [1 - 29]. APFs were associated with luminal involvement in 94.7% of cases, with ileal location in 10 patients (26.3%), colonic location in 13 patients (34.2%) and ileocolic location in 13 patients. The APFs were perianal in 34cases, vulvovaginal in five cases and gluteal in one case. There were complex fistulas in 92.1% of cases. The number of external orifices at the time of diagnosis was respectively: 1 orifice in 63.2% of cases, 2orifices in 26.3% of cases and more than two orifices in 10.5% of cases. A perineal abscess was associated in 44.7% of cases and anorectal stricture was observed in 7.9% of patients. Seton drainage was performed in 86.6% of patients. All patients with complex APF had received anti-TNFα after disappearance of collections if initially present (infliximab (92.1%), adalimumab (7.9%)) combined with thiopurines in 97.4% of cases. After a mean follow-up of 40 months, a complete remission was observed in 14 patients (36.8%), a partial response was noted in 13 patients (34.2%). 11 patients (28.9%) were in therapeutic failure. Conclusion In our study, APFs during CD account for almost half of all APLs.Thus, the development of local therapeutic means proves to be of necessity in order to increase the efficacy of biotherapies and to accelerate the healing of APFs.

P264 Prevalence and predictors of stoma formation and restoration of intestinal continuity in patients with Crohn’s disease in a tertiary referral hospital: A retrospective explorative study

Abstract Background Crohn’s disease (CD) is associated with a high risk of intestinal complications such as stricture, fistula and abscess formation, as well as perianal disease, frequently requiring surgical procedures and intestinal stoma formation. The aim of the present study was to evaluate the prevalence as well as predictors for surgical stoma formation in CD patients. Methods This is a retrospective single tertiary center cohort study of 1157 patients with CD with a median follow-up of 15 years whose characteristics (Table 1) are recorded via a validated data software (IBDIS, Inflammatory Bowel Disease Information System). The primary objective was the assessment of risk factors for intestinal stoma formation during follow-up. The probability of stoma-free survival was calculated for the entire patient population and for subgroups defined by their time of diagnosis (-1999, 2000–2009, 2010-), location and behavior of disease, presence of perianal disease (ever), gender, and smoking habits by means of Kaplan-Meier estimates. Results 135 (11.7%) patients with intestinal stomas [78 (57.8%) ileostomies and 57 (42.2%) colostomies] were registered. The probability of stoma-free survival after 5, 10, and 20 years was 95.9%, 91.8%, and 85.5%, respectively. Stoma formation surgery was elective in 51 (37.8%) cases, emergency in 49 (36.3%) and unknown in the others (25.9%). The most common indications were perianal disease [(n=34; 25.2%), internal fistula/abscess [n=25 (18.5%)], postoperative complications [n=21 (15.6%)], stricture [n=11 (8.1%)], and refractory to treatment [n=10 (7.4%)]. The probability of stoma-free survival was significantly lower in patients with perianal disease (p&amp;lt;0.0001) (Figure 1), colon involvement (p&amp;lt;0.0001) (Figure 2), and penetrating disease behavior (p&amp;lt;0.0001) (Figure 3). Time of diagnosis, gender, and smoking habit were not significantly associated with stoma-free survival. In 73 (54.1%) patients a restorative surgery for intestinal continuity was performed. Conclusion We found a high prevalence of intestinal stoma formation in CD patients of a tertiary center. Patients with perianal disease, penetrating behavior and colonic location, have a lower probability of stoma-free survival.

P178 Fecal incontinence and rectal anal function in Crohn’s Diseases patients

Abstract Background Anoperineal damage in Crohn’s Disease (CD) is caused by inflammation, its sequelae, and the surgery’s sequelae. Fecal incontinence (FI) is an important complaint reported by patients with CD. Literature data regarding to FI, anatomical and functional abnormalities and its associated clinical factors are controversial, with few surveys with a limited number of participants.1 The aim of this study is to analyze FI and the associated manometric and clinical findings in patients with CD. Methods Observational, cross-sectional study in patients older than 18 years old with CD under outpatient follow-up at a tertiary center, who, after sign informed consent, were submitted to specific questionnaire, anorectal manometry and medical record review. The Jorge and Wexner Fecal Incontinence Scale was applied to grade incontinence.2 SPSS 21.0 (SPSS, Chicago, IL, USA) was used for statistical analysis, with description of categorical variables with absolute and relative frequency, and continuous variables with median and interquartile range (IIQ). To study the association, we used Pearson’s Chi-Square and Mann Whitney test. The null hypothesis was rejected with p&amp;lt;0.05. Results Of 104 patients with CD, 51% were male, median age of 41 years old (IIQ 29.2–50.0) and median disease duration of 6.1 years (IIQ 2.5 to 11 .5). Most of the sample was diagnosed between 17 and 40 years old, (68.3%), with non-penetrating, non-stricturing disease (63.4%), with colonic location (77.9%), isolated (30.8%) or with ileal involvement (47.1%); 78.8% had disease in remission and 11.5% had mild disease, representing 90,4% of our casuistic, according to the Harvey Bradshaw Index. Among patients; 41.3% had perianal disease, and 49% were incontinent, of these 66.7% had mild incontinence and 33.3% had moderate and severe incontinence. It was found association between FI and lower mean resting pressures (p=0.04) and lower mean squeeze pressures (p=0.04) along the anal canal. There was also association between FI and perianal disease (p=0.02), and FI and disease activity (p&amp;lt;0.01). Conclusion The study, unprecedented in America Latin, showed a high frequency of FI and found its association with disease activity, structural abnormalities (perianal disease) and anorectal disfunction (lower resting and squeeze pressures), reenforcing the importance of controlling CD activity. Furthermore, the data showed to be crucial during follow-up of CD patients the adequate manometric assessment and specialized evaluation for the management of FI.

P708 Ileal involvement defined by Montreal classification in Crohn’s disease is associated with a distinct microbial composition in ileal and colonic mucosa

Abstract Background The Montreal classification of inflammatory bowel disease (IBD) recognizes distinct subgroups based on location of disease, age at onset and behaviour for Crohn’s disease (CD) and extent in ulcerative colitis (UC). CD with ileal involvement is in part genetically determined and tends to progress to surgery and to be more refractory to medical therapy compared to colonic disease location. We investigated the association of different aspects of the Montreal classification with the ileal and colonic mucosa-associated microbiota. Methods Healthy control (HC) and IBD patients underwent colonoscopy with biopsy samples taken from terminal ileum, ascending and sigmoid colon. Mucosal 16s rRNA gene profiling was analysed and an amplicon sequence variant table was generated and normalized. Patients with prior intestinal resection, IBD-unclassified and recent antibiotic exposure were excluded. Endoscopic activity was defined as a segmental Mayo endoscopic subscore &amp;gt; 0 in UC and a simple endoscopic score &amp;gt; 2 in CD. Blood samples were drawn for genotyping and a weighted genetic risk score (GRS) was built based on 169 IBD risk variants. Pooled ileal and colonic samples were analysed for taxonomic differential abundance (DA) among the variables of the Montreal classification using a linear mixed-effects model (MaAsLin2) with age, sex, biopsy site, endoscopic activity and GRS as covariates. P-values were corrected for false discovery rate (FDR) and &amp;lt; 5% was considered significant. Results A total of 546 biopsy samples from 201 IBD patients and 48 HC were analysed. The characteristics of the cohort and Montreal classification are depicted in the Table. At colonoscopy 168 samples (31.4%) showed endoscopic activity. The multivariate analysis revealed that the genera Agathobacter and Faecalibacterium, as well as the family Ruminococacceae and the order Oscillospirales were significantly reduced in CD with ileal involvement (L1+L3) when compared to either isolated colonic CD (L2), UC (any extent) and HC independent of age, sex, endoscopic activity, biopsy site, and GRS (Figure). Samples from UC and isolated colonic CD patients did not show differences in their microbial profile irrespective of biopsy site. No differences in DA were observed in subgroups based on age at onset and disease behaviour in CD or extent in UC. GRS was not associated with microbial composition. Conclusion These data suggest that CD with ileal involvement (Montreal L1+L3) is a major determinant of the tissue-associated microbial composition in both ileal and colonic mucosa irrespective of variables such as endoscopic activity and GRS. The reduction of several beneficial microbes in CD with ileal involvement might partially explain the more progressive phenotype in such patients.

P260 Autoimmune pancreatitis in patients with Inflammatory Bowel Disease: results from a multicentre ECCO CONFER cases series

Abstract Background Autoimmune pancreatitis (AIP) is an uncommon inflammatory disorder that may accompany inflammatory bowel disease (IBD). The clinical relevance of AIP-IBD coexistence, therapeutic strategies, and long-term outcomes are scarcely known. Methods In this ECCO COllaborative Network For Exceptionally Rare case reports project (ECCO-CONFER) we included cases of AIP diagnosed in patients with IBD. Data on the diagnostic criteria, clinical characteristics, and patient outcomes were retrospectively collected and analysed. Results The cohort included 82 patients [54% males, 77% with ulcerative colitis (UC), age at IBD and AIP diagnosis 32±16 and 35±16 years, respectively]. Of all AIP patients, 71% were classified as type 2, 21% as type 1, and 8% as undefined type. Detailed characteristics of the study group are shown in Table 1. In 57% of the individuals, IBD was diagnosed before AIP. In the remaining cases, IBD was diagnosed simultaneously (20%) or afterwards (23%). Half of the patients required immunomodulators and 43% biological therapy to control their IBD. Twenty-two percent of UC and 6% of Crohn’s disease (CD) required surgical intervention during a mean follow-up of 3.6±3.4 years. Histological confirmation was used in 38% of cases, while the remaining were diagnosed as probable AIP based on clinical, biochemical, and radiologic criteria. Magnetic resonance was the most frequently used imaging modality (61%). Eighty percent of patients received steroids for AIP. Thiopurines were used for AIP in 16 (19%) patients, 81% of them responded to treatment. One patient was successfully treated for AIP with infliximab. AIP complications occurred in 27%, including pancreatic exocrine insufficiency (19%) and diabetes (13%). Five patients underwent surgery due to suspected pancreatic cancer. Patients with complicated AIP were significantly older at AIP and IBD diagnosis, were more frequently males and presented with weight loss at AIP diagnosis, and had less frequently a family history of IBD (Table 1). Colonic IBD (i.e. UC, isolated colonic IBD-unclassified or colonic CD) was seen in a higher proportion of individuals with complicated vs benign AIP course (91% vs 33%, p&amp;lt;0.0001). At the end of follow-up, 75 (91%) and 73 (89%) patients were in remission of AIP and IBD, respectively. No IBD or AIP-related deaths were reported. Conclusion In this large international cohort of patients with concomitant AIP-IBD, most patients have type 2 AIP and colonic IBD. AIP course is relatively benign, and long-term outcomes are favourable. Older age, male gender, isolated colonic IBD location, and weight loss at AIP presentation were seen in higher proportions of patients with a complicated course of AIP.

DOP66 Disease course of Ulcerative proctitis in children: A population based study on behalf of the SIGENP IBD Group

Abstract Background Ulcerative proctitis (UP), defined as a colonic location limited to the rectum, is a poorly investigated condition in children, usually considered as a minor form of Ulcerative Colitis (UC). The aim of the present study was to compare the disease course of paediatric patients affected by UP at diagnosis with the other UC locations. Methods This multicentre retrospective observational study has been carried out starting from the data prospectively registered in the IBD Registry of the Italian Society of Pediatric Gastroenterology, Hepatology and Nutrition (SIGENP). Seventeen IBD referral centres adhering to the registry were included in the study. Patients age 0 to 18 years, who were diagnosed with UC according to the Porto criteria starting from January 1, 2009, to May 1st, 2021 were identified. Only children with a minimum follow-up of 12 months were included in the study. Once enrolled, children were subsequently divided in two groups based on Paris classification: group 1 (E1) and group 2 (E2, E3 and E4). Results Eight-hundred-eighty-five children were finally included in the study (median age at diagnosis: 11.2 years, range: 0–18 years; M/F: 434/451), of whom 176 (19.8%) belonging to group 1 and 709 (80.1%) to group 2. The median age at diagnosis was significantly higher in group 1 when compared to group 2 [11.9 (0–18) versus 11 (0–18) years, respectively; (p&amp;lt;0.001)]. At diagnosis, the induction therapy was significantly different with 68 (39.5%) patients of group 1 undergoing steroid therapy versus 505 (71.2%) of group 2 (p&amp;lt;0.001) and 79 (41.9%) of group 1 practising only mesalamine respect to 186 (26.2%) of group 2 (p&amp;lt;0.001). A higher number of children from group 2 started immunosuppressive or biologic therapy as maintenance therapy at diagnosis [Group 1: 11 (6.2%) versus 173 (24.4%), respectively; (p&amp;lt;0.001)]. The median follow-up of our cohort was 4.5 years (range 1–13 years). At the last follow-up, 67/176 (38%) children with UP showed an extension of their disease location without significant difference when compared to group 2 [265 (37.5%); p=0.9], while 81 (45%) children from Group 1 were under immunosuppressive or biologic therapy versus 566 (79.8%) from group 2 (p&amp;lt;0.001). Five children (3%) of Group 1 underwent colectomy during the follow up versus 45 (6.9%) of Group 2 (p=0.06). Conclusion UP is a frequent location of paediatric onset UC and the risk of endoscopic extension of proctitis is similar to the more extensive forms. A considerable number of patients with UP required immunosuppressive or biologic therapy during the follow-up and no significant difference was observed in terms of surgery. Overall, UP cannot be considered as a minor form of UC.

P122 Low Risk of new dysplastic lesions during inflammatory bowel disease surveillance with dye-cromoendoscopy: a multicenter population-based retrospective study

Abstract Background The 21st century has witnessed advances in endoscopic surveillance technology such as high-definition imaging and virtual or dye-based chromoendoscopy, which have led to increased detection of dysplasia. It is unknown the rates of new dysplastic lesions or cancer progression with these techniques though it seems lower than previously described. Methods We developed a multicenter, population-based and retrospective cohort from 7 Spanish hospitals from the Group of Inflammatory bowel disease of Castilla Y Leon (GEICYL) including sequentially all patients with inflammatory bowel disease and colonic dysplastic lesions completely resected (R0) in surveillance with dye-based indigo carmine chromoendoscopy between January 2013 and December 2019, with a minimum endoscopic follow-up of 12 months. The aim was to evaluate the risk of developing more advanced metachronous neoplasia during follow-up, analysing possible associated risk factors. Results A total of 99 patients and 148 index lesions (145 low-grade dysplasias [LGD] and 3 high-grade dysplasias [HGD]) with a medium follow-up of 48.76 months (IQR: 36.34 – 67.15) were included. Patients and IBD baseline characteristics are reflected in table 1. During follow-up, 37 patients developed 97 new dysplastic lesions (92 LGD, 4 HGD and 1 CRC) and 1 patient developed multifocal invisible dysplasia (3 HGD). The overall incidence rate for new dysplastic lesions was 0.23 per 100 patient-year, 1.15 per 100 patients at 5 years and 2.29 per 100 patients at 10 years (Figure 1). Personal history of dysplasia was associated with higher risk of developing any grade of dysplasia during follow-up (p 0.025), meanwhile, left colon lesions was associated with a lower risk (p 0.043). 6 patients developed more advanced lesions (5 patients HGD and 1 CCR) with an incidence rate at year and 10 years of 1% and 14% respectively; LGD lesion &amp;gt;1cm was a risk factor for developing HGD or CRC (p 0.041), meanwhile LGD lesion &amp;lt; 1 cm was a protective factor (p 0.013) (table 2,3). 1/8 patients (13%) with HGD lesions developed CRC during follow-up. 3 patients were colectomized (2 by HGD and 1 by CRC). Neither mesalamine treatment or immunosuppressive or biological treatment were associated with a lower risk of dysplasia development. Conclusion Risk of dysplasia progression to advanced neoplasia and specifically risk of new neoplastic lesions after endoscopic resection of colitis-associated dysplasia are very low in our cohort with dye-chromoendoscopy. Personal history of dysplasia, as risk factor, and left colon location, as protective factor, were associated with new dysplastic lesions. Finally, size above 1 cm was the only risk factor for progression to advanced lesions.

P288 Recurrence rates of advanced neoplasia after endoscopic or surgical resection in Inflammatory Bowel Disease patients: a retrospective cohort study

Abstract Background Inflammatory bowel disease (IBD) patients are at increased risk of advanced neoplasia (AN) including high grade dysplasia (HGD) and colorectal cancer (CRC). Historically, a (sub)total colectomy was recommended in these patients, but alternatively, endoscopic resection or partial colectomy can be considered as well. We aimed (1) to identify factors associated with AN treatment choice and (2) to assess AN recurrence rates following different treatment modalities. Methods In this retrospective multi-center cohort study we used the Dutch nationwide histopathology registry (PALGA) to identify ulcerative colitis (UC), Crohn’s disease (CD) and IBD-unclassified patients diagnosed with colonic AN between 1991 and 2020 in seven hospitals in the Netherlands. Exclusion criteria were familial CRC or AN prior to IBD diagnosis. Data regarding the first (index) AN, treatment and endoscopic and surgical follow-up were collected. Recurrence was defined as colorectal AN (independent of colonic location) detected after treatment of index AN. Multinomial logistic regression and cox regression analysis were used to assess in respective associations with treatment choice and recurrence free survival. Results We included 189 patients with index AN (n=81 HGD, n=108 CRC) with a median follow up of 27 months (IQR 7–69 months). (Sub)total colectomy was performed in 79 patients (41.8%; n=33 HGD, n=46 CRC), whereas 55 patients (29.1%; n=12 HGD, n=43 CRC) had a partial colectomy. Endoscopic resection was performed in 38 patients (20.1%; n=35 HGD, n=3 CRC), of which EMR/ESD n=12 (6.3%). Seventeen lesions (8.9%; n=1 HGD, n=16 CRC) were not removed, due to comorbidity or metastatic disease. CRC, primary sclerosing cholangitis (PSC), extensive disease and younger age at time of index AN were associated with (sub)total colectomy (Table 1). Twenty-one patients (12.2%) developed recurrence AN (n=12 HGD, n=9 CRC), after a median of 24 months (IQR 14–48; figure 1). Endoscopic resection was associated with recurrence (adjusted hazard ratio 4.0, confidence interval [1.3–12.2], p=0.02), as 14/21 patients (66.7%) with recurrence were initially (for index AN) treated with endoscopic resection. In addition, 3 patients (14.3%) were treated with partial colectomy and 4 (19.0%) with (sub)total colectomy. In 11/21 patients (52.4%) recurrence was treated with surgical resection. Conclusion Factors associated with AN treatment with (sub)total colectomy were CRC, PSC, extensive disease and younger age. After AN treatment, 1 out of 10 IBD patients developed recurrence of AN, mainly after endoscopic resection. This underlines the importance of stringent endoscopic surveillance following treatment of AN, especially after endoscopic resection with residual colon in place.

Contrast Enhanced Ultrasound Molecular Imaging of Spontaneous Chronic Inflammatory Bowel Disease in an Interleukin-2 Receptor α-/- Transgenic Mouse Model Using Targeted Microbubbles.

Inflammatory bowel disease (IBD) is a lifelong inflammatory disorder with relapsing–remission cycles, which is currently diagnosed by clinical symptoms and signs, along with laboratory and imaging findings. However, such clinical findings are not parallel to the disease activity of IBD and are difficult to use in treatment monitoring. Therefore, non-invasive quantitative imaging tools are required for the multiple follow-up exams of IBD patients in order to monitor the disease activity and determine treatment regimens. In this study, we evaluated a dual P- and E-selectin-targeted microbubble (MBSelectin) in an interleukin-2 receptor α deficient (IL-2Rα−/−) spontaneous chronic IBD mouse model for assessing long-term anti-inflammatory effects with ultrasound molecular imaging (USMI). We used IL-2Rα−/− (male and female on a C57BL/6 genetic background; n = 39) and C57BL/6 wild-type (negative control; n = 6) mice for the study. USMI of the proximal, middle, and distal colon was performed with MBSelectin using a small animal scanner (Vevo 2100) up to six times in each IL-2Rα−/− mouse between 6–30 weeks of age. USMI signals were compared between IL-2Rα−/− vs. wild-type mice, and sexes in three colonic locations. Imaged colon segments were analyzed ex vivo for inflammatory changes on H&E-stained sections and for selectin expression by immunofluorescence staining. We successfully detected spontaneous chronic colitis in IL-2Rα−/− mice between 6–30 weeks (onset at 6–14 weeks) compared to wild-type mice. Both male and female IL-2Rα−/− mice were equally (p = 0.996) affected with the disease, and there was no significant (p > 0.05) difference in USMI signals of colitis between the proximal, middle, and distal colon. We observed the fluctuating USMI signals in IL-2Rα−/− mice between 6–30 weeks, which might suggest a resemblance of the remission-flare pattern of human IBD. The ex vivo H&E and immunostaining further confirmed the inflammatory changes, and the high expression of P- and E-selectin in the colon. The results of this study highlight the IL-2Rα−/− mice as a chronic colitis model and are suitable for the long-term assessment of treatment response using a dual P- and E-selectin-targeted USMI.

Endoscopic direct clipping versus indirect clipping for colonic diverticular bleeding: A large multicenter cohort study.

BackgroundDirect and indirect clipping treatments are used worldwide to treat colonic diverticular bleeding (CDB), but their effectiveness has not been examined in multicenter studies with more than 100 cases.ObjectiveWe sought to determine the short‐ and long‐term effectiveness of direct versus indirect clipping for CDB in a nationwide cohort.MethodsWe studied 1041 patients with CDB who underwent direct clipping (n = 360) or indirect clipping (n = 681) at 49 hospitals across Japan (CODE BLUE‐J Study).ResultsMultivariate analysis adjusted for age, sex, and important confounding factors revealed that, compared with indirect clipping, direct clipping was independently associated with reduced risk of early rebleeding (<30 days; adjusted odds ratio [AOR] 0.592, p = 0.002), late rebleeding (<1 year; AOR 0.707, p = 0.018), and blood transfusion requirement (AOR 0.741, p = 0.047). No significant difference in initial hemostasis rates was observed between the two groups. Propensity‐score matching to balance baseline characteristics also showed significant reductions in the early and late rebleeding rates with direct clipping. In subgroup analysis, direct clipping was associated with significantly lower rates of early and late rebleeding and blood transfusion need in cases of stigmata of recent hemorrhage with non‐active bleeding on colonoscopy, right‐sided diverticula, and early colonoscopy, but not with active bleeding on colonoscopy, left‐sided diverticula, or elective colonoscopy.ConclusionsOur large nationwide study highlights the use of direct clipping for CDB treatment whenever possible. Differences in bleeding pattern and colonic location can also be considered when deciding which clipping options to use.

Epidemiology and Natural History of Perianal Crohn's Disease: A Systematic Review and Meta-Analysis of Population-Based Cohorts.

Perianal Crohn's disease (pCD) is a potentially severe phenotype of CD. We conducted a systematic review with meta-analysis to estimate cumulative incidence, risk factors, and outcomes of pCD in population-based cohort studies. Through a systematic literature review through March 1, 2021, we identified population-based inception cohort studies reporting cumulative incidence of perianal disease (primarily abscess and/or fistula) in patients with CD. We estimated the cumulative incidence of pCD at presentation and 1-, 5-, and 10-year follow-up, and risk factors for perianal disease and outcomes including risk of major (bowel resection, proctectomy, ostomy) and minor perianal (incision and drainage, seton placement, etc.) surgery. In 12 population-based studies, prevalence of pCD was 18.7% (95% confidence interval [CI], 12.5%-27.0%) with 1-, 5-, and 10-year risk of perianal disease being 14.3% (95% CI, 7.9%-24.6%), 17.6% (95% CI, 11.3%-26.5%), and 18.9% (95% CI, 15.0%-23.4%), respectively. Approximately 11.5% of patients (95% CI, 6.7%-19.0%) had perianal disease at or before CD diagnosis. Colonic disease location and rectal involvement were associated with higher risk of pCD. Overall, 63.3% of patients (95% CI, 53.3-72.3) required minor perianal surgery and 6.4% of patients (95% CI, 1.8%-20.6%) required major abdominal surgery for pCD. Use of biologic therapy for pCD is common and has steadily increased throughout the years. Approximately 1 in 5 patients with CD develops perianal disease within 10 years of CD diagnosis, including 11.5% who have perianal disease at presentation. Approximately two-thirds of patients require perianal surgery, with a smaller fraction requiring major abdominal surgery.

Full-Thickness Laparoendoscopic Excision for Management of Complex Colon Polyps.

Benign colon polyps are increasingly being detected because of improved colonoscopic screening and early detection of masses on the adenoma-to-carcinoma pathway. Full-thickness laparoendoscopic excision is a colon-preserving technique for endoscopically unresectable polyps consisting of endoscopically guided nonanatomic wedge colectomy. This study aimed to evaluate the safety and success of full-thickness laparoendoscopic excision compared to segmental colectomy for complex polyps not amenable to endoscopic resection. This is a retrospective case-control study. This study was conducted at a tertiary academic center. A prospectively maintained institutional database identified 22 patients with benign complex polyps managed with full-thickness laparoendoscopic excision from 2015 to 2020. These patients were compared with 22 propensity score-matched controls from the same database that underwent laparoscopic segmental colectomy. Primary outcome was inpatient length of stay. Secondary outcomes included operative details and postoperative morbidities. Full-thickness laparoendoscopic excision was successful in all patients. Patients had a median age of 64 years (41-85), and 82% were men. Final pathology revealed complete excision of benign lesions in 20 of 22 patients and adenocarcinoma in 2 of 22. For the adenocarcinomas, 1 patient underwent subsequent elective colectomy without complications, and 1 patient declined surgery. Propensity score matching was successful for age, sex, BMI, ASA score, colon location, and prior abdominal surgery. Compared with controls, cases had significantly shorter operative time (89.5 minutes (46-290) vs 122 minutes (85-200), p = 0.009), length of stay (1 day (0-17) vs 3 days (1-8), p < 0.001), and reduced blood loss (5 mL (2-15) vs 25 mL (10-150), p < 0.001). Thirty-day morbidity (9.1% vs 27.3%, p = 0.240) was not significantly different. An unplanned 30-day reoperation was performed in 1 patient for suspected small-bowel obstruction. There was 1 mortality due to decompensated cirrhosis in the treatment group. This study was limited by its single-institution retrospective design. Full-thickness laparoendoscopic excision is safe and successful compared with corresponding segmental colectomy for complex polyps. Favorable postoperative outcomes, including decreased operative time, length of stay, and blood loss, make it a useful approach for managing complex polyps throughout the colon.

Endoscopic resection outcomes and predictors of failed en bloc endoscopic mucosal resection of colorectal polyps ≤ 20 mm among advanced endoscopy trainees.

Background and study aims En bloc endoscopic mucosal resection (EMR) is preferred over piecemeal resection for polyps ≤ 20 mm. Data on colorectal EMR training are limited. We aimed to evaluate the en bloc EMR rate of polyps ≤ 20 mm among advanced endoscopy trainees and to identify predictors of failed en bloc EMR. Methods This was a multicenter prospective study evaluating trainee performance in EMR during advanced endoscopy fellowship. A logistic regression model was used to identify the number of procedures and lesion cut-off size associated with an en bloc EMR rate of ≥ 80 %. Multivariate analysis was performed to identify predictors of failed en bloc EMR. Results Six trainees from six centers performed 189 colorectal EMRs, of which 104 (55 %) were for polyps ≤ 20 mm. Of these, 57.7 % (60/104) were resected en bloc. Trainees with ≥ 30 EMRs (OR 6.80; 95 % CI: 2.80–16.50; P = 0.00001) and lesions ≤ 17 mm (OR 4.56;95 CI:1.23–16.88; P = 0.02) were more likely to be associated with an en bloc EMR rate of ≥ 80 %. Independent predictors of failed en bloc EMR on multivariate analysis included: larger polyp size (OR:6.83;95 % CI:2.55–18.4; P = 0.0001), right colon location (OR:7.15; 95 % CI:1.31–38.9; P = 0.02), increased procedural difficulty (OR 2.99; 95 % CI:1.13–7.91; P = 0.03), and having performed < 30 EMRs (OR: 4.87; 95 %CI: 1.05–22.61; P = 0.04). Conclusions In this pilot study, we demonstrated that a relatively low proportion of trainees achieved en bloc EMR for polyps ≤ 20 mm and identified procedure volume and lesion size thresholds for successful en bloc EMR and independent predictors for failed en bloc resection. These preliminary results support the need for future efforts to define EMR procedure competence thresholds during training.