title: In vivo assessment of tumour angiogenesis in colorectal cancer: the role of confocal laser endomicroscopy.
abstract: OBJECTIVE
  Tumour neoangiogenesis is a key factor in tumour progression and metastatic spread and the possibility to assess tumour angiogenesis might provide prognostic information. The aim of this study was to establish the role of probe-based confocal laser endomicroscopy (p-CLE) in the identification of vascular architecture and specific morphological patterns in normal colorectal mucosa and malignant lesions during routine endoscopy.
  
  
  METHODS
  Fourteen consecutive patients with colorectal cancer were included. The following features were identified and then compared between normal and neoplastic mucosa on p-CLE images: vessel shape (straight vs irregular) vessel diameter the 'branching patterns' vessel permeability (fluorescein leakage) and blood flow (normal vs defective flux). Immunohistochemistry was used to confirm the presence and to study the morphology of vascular structures (CD-34 staining) and 'neo-vessels' (WT-1 staining) on tumour and normal mucosal sections.
  
  
  RESULTS
  Tumour vessels appeared as irregular, ectatic and with a highly variable calibre and branching patterns on p-CLE images. The mean diameter of tumour vessels was significantly larger than those in normal mucosa (weighted mean difference 3.38, 95% CI 2.65-4.11, P = 0.01). Similarly, 'vessel branching' (OR 2.74, 95% CI 1.23-6.14, P = 0.01), fluorescent dye 'extravasation' (OR 3.46, 95% CI 1.39-8.57, P = 0.01) were significantly more frequent in colorectal cancer than in normal colorectal mucosa. Immunohistochemistry corroborated the p-CLE findings, showing higher vascularity in tumour sections due to neoformed vessels, presenting irregular patterns.
  
  
  CONCLUSIONS
  Probe-based confocal laser endomicroscopy provides a noninvasive characterization of the microvascular architecture of colonic mucosa. Different morphological patterns have been described, discriminating normal and malignant microvascular networks in colorectal mucosa.
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: G D
authors.initials: GD
authors.lastname: De Palma
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Maione
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Esposito
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Luglio
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: M C
authors.initials: MC
authors.lastname: Giglio
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Siciliano
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Gennarelli
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Cassese
authors.affiliation: Department of Advanced Biomedical Sciences, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Campione
authors.affiliation: Department of Advanced Biomedical Sciences, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: F P
authors.initials: FP
authors.lastname: D'Armiento
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples Federico II, School of Medicine, Naples, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Bucci
mesh_terms: D000328:Adult; D003106:Colon / Q000098:blood supply / Q000473:pathology; D015179:Colorectal Neoplasms / Q000098:blood supply*; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000098:blood supply / Q000473:pathology; D008297:Male; D018613:Microscopy, Confocal / Q000379:methods*; D055806:Microvessels / Q000473:pathology*; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000473:pathology*
keywords: Colorectal cancer; neoangiogenesis, confocal laser endomicroscopy