title: Submucosal Plexitis as a Predictive Factor for Postoperative Endoscopic Recurrence in Patients with Crohn's Disease Undergoing a Resection with Ileocolonic Anastomosis: Results from a Prospective Single-centre Study.
abstract: OBJECTIVE
  Ileocolonoscopy allows early detection of recurrence after surgical resection for Crohn's disease [CD]. Plexitis, defined as presence of inflammatory cells in or around enteric ganglia or nerve bundles, in the proximal surgical margin has been associated with an increased overall recurrence risk. We investigated prospectively whether plexitis can predict endoscopic recurrence [ER] in a consecutive cohort of CD patients undergoing ileocolonic resection.
  
  
  METHODS
  All CD patients undergoing ileocolonic resection in our institution between October 2009 and December 2012 were eligible for this study. Clinical data were obtained prospectively from the patients' files, and biopsies from the proximal surgical margins were analysed immunohistochemically for inflammation at the myenteric and submucosal plexus [lymphocytes, mast cells, eosinophils]. The degree of plexitis was correlated with the presence of ER at 6 months, defined as a modified Rutgeerts' score of ≥ i2b. Multivariate models were developed and tested to predict posterior probability of ER.
  
  
  RESULTS
  A total of 74 patients were included. Six months after ileocolonic resection, 50% showed ER. Known risk factors such as penetrating disease, previous resections, and active smoking, showed no relation with ER. On the other hand, submucosal lymphocytic plexitis was associated with ER [p = 0.020]. The predictive value of lymphocytic cell count increased with more extensive biopsy sampling and with application of immunohistochemistry.
  
  
  CONCLUSIONS
  Submucosal lymphocytic plexitis in the proximal surgical margin was significantly related with a higher risk for ER after ileocolonic resection. These data support development of a postoperative prevention trial with vedolizumab, which may block lymphocytic trafficking in the postoperative bowel.
authors.affiliation: Translational Cell & Tissue Research, Department of Imaging and Pathology, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Bart
authors.initials: B
authors.lastname: Lemmens
authors.affiliation: Translational Research in Gastrointestinal Disorders [TARGID], Department of Clinical and Experimental Medicine, University Hospitals Leuven, KU Leuven, Leuven, Belgium.|Department of Abdominal Surgery, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Anthony
authors.initials: A
authors.lastname: de Buck van Overstraeten
authors.affiliation: Translational Research in Gastrointestinal Disorders [TARGID], Department of Clinical and Experimental Medicine, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Arijs
authors.affiliation: Translational Cell & Tissue Research, Department of Imaging and Pathology, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Xavier
authors.initials: X
authors.lastname: Sagaert
authors.affiliation: Translational Research in Gastrointestinal Disorders [TARGID], Department of Clinical and Experimental Medicine, University Hospitals Leuven, KU Leuven, Leuven, Belgium.|Department of Gastroenterology and Hepatology, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Gert
authors.initials: G
authors.lastname: Van Assche
authors.affiliation: Translational Research in Gastrointestinal Disorders [TARGID], Department of Clinical and Experimental Medicine, University Hospitals Leuven, KU Leuven, Leuven, Belgium.|Department of Gastroenterology and Hepatology, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Séverine
authors.initials: S
authors.lastname: Vermeire
authors.affiliation: Department of Pathology, First Moscow State Medical University, Moscow, Russia.
authors.forename: Alexander
authors.initials: A
authors.lastname: Tertychnyy
authors.affiliation: Translational Cell & Tissue Research, Department of Imaging and Pathology, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Karel
authors.initials: K
authors.lastname: Geboes
authors.affiliation: Department of Abdominal Surgery, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Albert
authors.initials: A
authors.lastname: Wolthuis
authors.affiliation: Department of Abdominal Surgery, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Andre
authors.initials: A
authors.lastname: D'Hoore
authors.affiliation: Translational Cell & Tissue Research, Department of Imaging and Pathology, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Gert
authors.initials: G
authors.lastname: De Hertogh
authors.affiliation: Translational Research in Gastrointestinal Disorders [TARGID], Department of Clinical and Experimental Medicine, University Hospitals Leuven, KU Leuven, Leuven, Belgium marc.ferrante@uzleuven.be.|Department of Gastroenterology and Hepatology, University Hospitals Leuven, KU Leuven, Leuven, Belgium.
authors.forename: Marc
authors.initials: M
authors.lastname: Ferrante
mesh_terms: D000328:Adult; D000714:Anastomosis, Surgical / Q000009:adverse effects / Q000379:methods; D003082:Colectomy / Q000009:adverse effects / Q000379:methods; D003106:Colon / Q000473:pathology / Q000601:surgery; D003424:Crohn Disease / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D007082:Ileum / Q000473:pathology / Q000601:surgery; D007249:Inflammation / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012008:Recurrence; D012307:Risk Factors; D013368:Submucous Plexus / Q000473:pathology*
keywords: Endoscopy; pathology; surgery