Chromoscopic Guided Endomicroscpy to Diagnose Colitis Associated Dysplasia
Condition: Ulcerative Colitis; Intraepithelial Neoplasia; Cancer
MeSH terms: Neoplasms; Carcinoma in Situ; Colitis; Colitis, Ulcerative; Ulcer
Study type: Interventional
Phase: Phase 3

Summary: 
      Timely diagnosis of intraepithelial neoplasias (premalignant condition)is of crucial
      importance for clinical management of ulcerative colitis. We assessed the value of combined
      chromoscopy and endomicroscopy for diagnosis of intraepithelial neoplasias in a randomised
      controlled trial.

      Endomicroscopy is a new device which enables microscopy of the mucosal layer during ongoing
      colonoscopy. Chromoscopy means topical staining of mucosal surface to unmask areas of
      interest, which are subsequently examined with the endomicroscopic system.
    

Detailed description: 
      Ulcerative colitis (UC) is an immune cell-mediated inflammatory bowel disease characterized
      by mucosal ulcerations, rectal bleeding, diarrhea, and abdominal pain. Patients with long
      standing UC face an increased risk for development of colitis associated colorectal cancer.
      Factors associated with increased risk for cancer development include the duration of the
      disease, extensive colonic involvement (pancolitis, backwash ileitis), primary sclerosing
      cholangitis and severe chronic active inflammation. Based on these observations, colonoscopic
      surveillance in patients with long-standing UC is highly recommended.

      The main objective of surveillance colonoscopy in UC is to detect neoplasia at a surgically
      curative and preferably pre-invasive stage. However, in contrast to sporadic colorectal
      cancer, the growing pattern of neoplastic tissue in UC is often flat and multifocal.
      Therefore, significant lesions during conventional colonoscopy in UC are frequently
      overlooked. Chromoscopy with topically applied dyes such as methylene blue or indigo carmine
      facilitates the endoscopic detection of flat, circumscribed colitis associated neoplastic
      changes in UC. In fact, five controlled studies showed that the diagnostic yield for the
      detection of intraepithelial neoplasia (IN) using chromoscopy is higher as compared to
      conventional colonoscopy with random biopsies. Based on the above studies, chromoscopy has
      recently been considered for incorporation into US guidelines for surveillance of patients
      with long-standing UC. However, although this technique does allow identification of mucosal
      lesions, it is not suitable for accurate endoscopic diagnosis of intraepithelial neoplasias
      in UC due to the lack of cellular resolution and subsurface imaging. For endoscopy, novel
      techniques allowing accurate diagnoses during ongoing examination are highly desirable and
      may allow appropriate and immediate therapeutic manoeuvres (e.g. resection versus biopsy).
      Recently, a miniaturized confocal microscope has been developed integrated in the distal tip
      of a conventional colonoscope . This new diagnostic technology for gastrointestinal
      endoscopy, denoted confocal endomicroscopy, enables histological evaluation of the mucosal
      layer during ongoing colonoscopy. Furthermore, in patients screened for sporadic colorectal
      cancer, surface and subsurface analysis at cellular and subcellular resolution can be used to
      predict intraepithelial neoplasias (INs) with high accuracy. However, due to the time
      required for examination of large surface areas, this technique is not suitable for screening
      of the entire colonic surface in UC to detect neoplasias in flat mucosa.

      In the present study, we employ chromoscopy to identify potential neoplastic lesions and
      combine this for the first time with endomicroscopy for the endoscopic diagnosis of colitis
      associated intraepithelial neoplasias in UC. Using such chromoscopy guided endomicroscopy we
      will ecaluate whether the diagnostic yield diagnosing IN can be significantly increased.
    

Intervention name(s): Endomicroscope
Intervention type(s): Device
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: Endomicroscopy; Chromoendoscopy; Chromoscopy; Ulcerative Colitis; Intraepithelial Neoplasia