title: Photodynamic diagnoses of malignant pleural diseases using the autofluorescence imaging system.
abstract: BACKGROUND
  We conducted a study on photodynamic diagnosis (PDD) using autofluorescence in video-assisted thoracic surgery for minute intrathoracic small dissemination or early malignant pleural mesothelioma.
  
  
  METHODS
  Autofluorescence is the spontaneous emission of light that occurs when mitochondria, lysosomes, and other intracellular organelles absorb light. In normal tissues, green autofluorescence of approximately 520 nm is observed in response to 400-450 nm blue excitation rays. However, in cancer lesions, green autofluorescence is reduced due to thickening of the mucosal epithelium, a decrease in autofluorescent substances, etc., and the color spectrum thus shifts to red-violet. This phenomenon is the basis of PDD.
  
  
  RESULTS
  The color spectrum shift was observed in all tumors located on the pleural surface but not in cases with pleural fibrous disease. Among patients with primary lung cancer, those with pleural infiltration (pl) scores of 1 or greater showed color spectrum shifts due to reduced autofluorescence.
  
  
  CONCLUSIONS
  Localization of pleural lesions by autofluorescence imaging was found to be useful. In primary lung cancer cases, differentiation between pl0 and pl1 lesions appears to be useful for determining therapeutic strategies including surgical procedures.
authors.affiliation: Department of Respiratory Center, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kitada
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Ohsaki
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Matsuda
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hayashi
authors.forename: Kei
authors.initials: K
authors.lastname: Ishibashi
mesh_terms: D055088:Early Detection of Cancer; D004867:Equipment Design; D005260:Female; D006801:Humans; D007430:Intraoperative Care; D008175:Lung Neoplasms / Q000473:pathology* / Q000556:secondary / Q000601:surgery; D008297:Male; D008654:Mesothelioma / Q000473:pathology* / Q000556:secondary / Q000601:surgery; D000086002:Mesothelioma, Malignant; D061206:Neoplasm Micrometastasis; D009367:Neoplasm Staging; D061848:Optical Imaging / Q000295:instrumentation*; D010997:Pleural Neoplasms / Q000473:pathology* / Q000556:secondary / Q000601:surgery; D011237:Predictive Value of Tests; D020775:Thoracic Surgery, Video-Assisted / Q000295:instrumentation*; D020708:Thoracoscopes