Introduction

Post-operative recurrence (POR) affects a substantial proportion of Crohn's disease (CD) patients following intestinal resection. While ileocolonoscopy remains the gold standard for detecting recurrence, its invasive nature and patient burden have spurred interest in non-invasive monitoring approaches. This study evaluates the performance of faecal calprotectin (FC) and cross-sectional imaging at different timepoints in predicting endoscopic recurrence in postoperative CD patients.

Aims & Methods

In this multicenter retrospective cohort of 895 CD patients who underwent ileocecal resection, we analyzed the diagnostic accuracy of FC measurements at 3, 6-12, and 18-24 months postoperatively for predicting endoscopic recurrence (Rutgeerts score ≥i2 or SES-CD ≥3). Additionally, we assessed the concordance between intestinal ultrasound (IUS) and magnetic resonance imagings (MRI) and endoscopic findings at both 6-12- and 18-24-months using kappa statistics.

Results

FC demonstrated modest discriminatory ability at 3 months (AUC 0.642, 95% CI: 0.530-0.753) and 6-12 months (AUC 0.653, 95% CI: 0.593-0.713), with improved performance at 18-24 months (AUC 0.676, 95% CI: 0.608-0.744). The optimal cutoff values for FC (47.5 μg/g at 3 and 6-12 months; 80.0 μg/g at 18-24 months) were substantially lower than standard thresholds (150-250 μg/g) used in non-operated patients.
At 6-12 months, radiological and endoscopic assessments showed moderate agreement (κ=0.426, p<0.001) with 63.2% concordance. At 18-24 months, IUS demonstrated superior agreement with endoscopic findings (κ=0.531, p<0.001; sensitivity 83.8%, specificity 72.7%) compared to MRI (κ=0.324, p<0.001). Notably, radiological remission at 18-24 months was identified as a significant protective factor against surgical recurrence (OR 0.356, 95% CI: 0.179-0.705, p=0.003).

Table I: Concordance between endoscopic and radiologic findings (IUS and MRI) for inflammation and remission at 18–24 months post-ileocecal resection. Abbreviations: IUS: Intestinal ultrasound, MRI: Magnetic resonance imaging.

Conclusion

Non-invasive monitoring with FC shows promise in postoperative CD surveillance, though diagnostic thresholds differ substantially from those established for non-operated patients. IUS demonstrates superior concordance with endoscopic findings compared to MRI, particularly at later timepoints. The protective role of radiological remission against surgical recurrence highlights the importance of transmural healing. Combining FC with radiological assessment, especially IUS, may provide a comprehensive, patient-friendly approach to monitoring postoperative CD, potentially reducing the need for invasive procedures in selected patients but further studies are needed in this direction.

Introduction

Post-ESD surveillance guidelines remain heterogeneous, with many centers favoring early surveillance colonoscopy (SC) despite low recurrence rates after curative resection. This study aimed to evaluate the safety and outcomes of delayed SC after R0 colorectal ESD for benign lesions and to identify risk factors for metachronous advanced neoplasia.

Aims & Methods

We retrospectively analyzed 1,097 patients who underwent colorectal ESD between 2013 and 2021. Clinical, procedural, and histological characteristics were recorded. Among 778 patients with available surveillance data, outcomes were compared between those who had early SC (<12 months) and those with delayed SC (>24 months). Rates of recurrence, advanced neoplasia, and colorectal cancer were assessed. Risk factors for metachronous advanced neoplasia were evaluated via univariate and multivariate analysis.

Results

Mean patient age was 74.3 ± 10.8 years; 54.1% were male. En bloc and R0 resection rates were 95.8% and 83.3%, respectively. Among patients with surveillance data, 82.6% underwent early SC, and 17.4% had late-only SC. The rate of advanced adenoma at first SC was low and comparable between early and late groups (3.9% vs. 6.7%, p = 0.167). The overall rate of metachronous advanced adenoma was 6.5%, with no significant difference between early and late strategies (6.1% vs. 8.9%, p = 0.25). All four colorectal cancers were detected in the early group; none occurred in the late-only group. Recurrence on the ESD scar was rare (1.5% overall), and no late recurrences occurred after a normal SC1. The only significant predictor of metachronous advanced neoplasia was the number of synchronous lesions at index colonoscopy (OR 1.16, 95% CI 1.07–1.27; p < 0.01).

Conclusion

Delayed surveillance colonoscopy 3 years after R0 colorectal ESD for benign lesions appears safe and effective in selected patients. The multiplicity of synchronous lesions could guide risk stratification. These findings support extending SC intervals after curative ESD, with potential to reduce unnecessary procedures.

References

Pimentel-Nunes P, Libânio D, Bastiaansen BAJ, Bhandari P, Bisschops R, Bourke MJ, et al. Endoscopic submucosal dissection for superficial gastrointestinal lesions: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2022. Endoscopy. juin 2022;54(6):591‑622.
Dai M, Xiao X, Guo CLT, Lui RN, Yip HC, Chu S, et al. The Long‐Term Risk of Metachronous Advanced Adenoma Recurrence After Endoscopic Submucosal Dissection for Colorectal Neoplasia: A Propensity‐Score Matched Longitudinal Cohort With 5‐Year Follow‐Up. United Eur Gastroenterol J. 21 déc 2024;13(2):210‑9.
Yoshida N, Naito Y, Siah KTH, Murakami T, Ogiso K, Hirose R, et al. High incidence of metachronous advanced adenoma and cancer after endoscopic resection of colon polyps ≥20 mm in size. Dig Endosc Off J Jpn Gastroenterol Endosc Soc. mars 2016;28(2):194‑202.

Introduction

Crohn’s disease (CD), as a type of inflammatory bowel disease (IBD), is characterized by chronic inflammation in the intestinal tract and its incidence is rising globally. The factors involved in causing or triggering Crohn’s disease (CD) have yet to be confirmed. We recently demonstrated that the intestinal microbiome composition is associated with the risk of CD development; however, its potential causal effect remains unknown. Our study investigated whether stool microbiome might contribute to or trigger dysregulated immune response by transplanting stool into germ-free mice (GFM).

Aims & Methods

Fecal samples were collected from 12 discordant pairs of siblings (one who did not develop CD referred to as Healthy Matched Control (HMC) and another who subsequently developed CD, referred to as pre-CD). These subjects were recruited as part of the Crohn's and Colitis Canada Genetic, Environmental, Microbial Project (CCC-GEM) project, a cohort of prospectively followed healthy first-degree relatives. The stool was transplanted into RAG1-/- GFM before T-cell transfer-induced colitis (3 transplanted mice per donor). Body weight was monitored for 6 weeks after T-cell transfer. Fecal Lipocalin-2 (LCN-2) was measured by ELISA to assess gut inflammation. Intestinal tissue damage was assessed by a validated histology scoring. Pro-inflammatory cytokine gene profiles of intestinal tissue were measured by qPCR. The feces of colitic mice were collected after 6 weeks of T-cell transfer and used to investigate metabolic profile measured by UHPLC-MS/MS.

Results

At week 2 after T-cell transfer, mouse recipients of pre-CD stool experienced greater weight loss than mice receiving stool from HMC (p=0.004). LCN-2 of pre-CD mice was significantly higher after T-cell transfer at week 3. Intriguingly, pre-CD stool recipient mice had a higher histological damage score in the ileum (p=0.031). Mice receiving pre-CD stool had increased expression of selected pro-inflammatory cytokine genes in the ileum including Tnfα, Il-1β, Ifnγ, Il-10 and Tgfβ compared to mice that received HMC stool. Colonic tissue showed significant increases in TNFα and Tgfβ in the mice recipient of the pre-CD stool. Moreover, pre-CD stool led to significant changes in 40 fecal metabolites compared to HMC microbiome (0.01<p≤0.05). Spearman correlation between certain metabolites and colitis markers in mouse was observed. Fecal metabolomics in humans revealed two shared metabolic pathways associated with future onset of CD and murine inflammatory markers. Notably, there was a positive correlation between sphingolipids in humans and mice that was associated with increased colitis in mice. Sphingolipid metabolites also demonstrated positive correlation with mouse colitis marker and human CD subclinical markers.

Conclusion

These results showed that transplanted pre-CD stool worsened T cell transfer colitis in mice compared to HMC stool. This suggests that stool microbiome of individuals with CD is functionally altered years before diagnosis, exhibiting greater inflammatory potential when transferred to susceptible mice. Modulating pre-CD microbiome composition and/or function could lead to novel methods of CD prevention.