title: Autofluorescence endoscopy with "real-time" digital image processing in differential diagnostics of selected benign and malignant lesions in the oesophagus.
abstract: BACKGROUND
  Oesophageal papilloma and Barrett's oesophagus are benign lesions known as risk factors of carcinoma in the oesophagus. Therefore, it is important to diagnose these early changes before neoplastic transformation.
  
  
  METHODS
  Autofluorescence endoscopy is a fast and non-invasive method of imaging of tissues based on the natural fluorescence of endogenous fluorophores. The aim of this study was to prove the diagnostic utility of autofluorescence endoscopy with digital image processing in histological diagnosis of endoscopic findings in the upper digestive tract, primarily in the imaging of oesophageal papilloma.
  
  
  RESULTS
  During the retrospective analysis of about 200 endoscopic procedures in the upper digestive tract, 67 cases of benign, precancerous or cancerous changes were found. White light endoscopy (WLE) image, single-channel (red or green) autofluorescence images, as well as green and red fluorescence intensities in two modal fluorescence image and red-to-green (R/G) ratio (Numerical Colour Value, NCV) were correlated with histopathologic results. The NCV analysis in autofluorescence imaging (AFI) showed increased R/G ratio in cancerous changes in 96% vs. 85% in WLE. Simultaneous analysis with digital image processing allowed us to diagnose suspicious tissue as cancerous in all of cases. Barrett's metaplasia was confirmed in 90% vs. 79% (AFI vs. WLE), and 98% in imaging with digital image processing. In benign lesions, WLE allowed us to exclude tissue as malignant in 85%. Using autofluorescence endoscopy R/G ratio was increased in only 10% of benign changes causing the picture to be interpreted as suspicious, but when both methods were used together, 97.5% were cases excluded as malignancies. Mean R/G ratios were estimated to be 2.5 in cancers, 1.25 in Barrett's metaplasia and 0.75 in benign changes and were statistically significant (p=0.04).
  
  
  CONCLUSIONS
  Autofluorescence imaging is a sensitive method to diagnose precancerous and cancerous early stages of the diseases located in oesophagus. Especially in two-modal imaging including white light endoscopy, autofluorescence imaging with digital image processing seems to be a useful modality of early diagnostics. Also in observation of papilloma changes, it facilitates differentiation between neoplastic and benign lesions and more accurate estimation of the risk of potential malignancy.
authors.affiliation: Chair and Clinical Department of Internal Diseases, Angiology and Physical Medicine, Centre for Laser Diagnostics and Therapy, Silesian Medical University, Bytom, Poland.
authors.forename: Karolina
authors.initials: K
authors.lastname: Sieroń-Stołtny
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kwiatek
authors.forename: Wojciech
authors.initials: W
authors.lastname: Latos
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Kawczyk-Krupka
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Cieślar
authors.forename: Agata
authors.initials: A
authors.lastname: Stanek
authors.forename: Damian
authors.initials: D
authors.lastname: Ziaja
authors.forename: Andrzej M
authors.initials: AM
authors.lastname: Bugaj
authors.forename: Aleksander
authors.initials: A
authors.lastname: Sieroń
mesh_terms: D001471:Barrett Esophagus / Q000175:diagnosis / Q000473:pathology; D003937:Diagnosis, Differential; D004935:Esophageal Diseases / Q000175:diagnosis* / Q000473:pathology*; D004938:Esophageal Neoplasms / Q000175:diagnosis / Q000473:pathology; D004945:Esophagoscopy / Q000379:methods*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D010212:Papilloma / Q000175:diagnosis / Q000473:pathology; D012189:Retrospective Studies