title: Using 5-aminolevulinic acid and pulsed dye laser for photodynamic treatment of oral leukoplakia.
abstract: OBJECTIVE
  To determine the safety and efficacy of photodynamic therapy in the treatment of oral leukoplakia with 5-aminolevulinic acid and pulsed dye laser.
  
  
  METHODS
  Nonrandomized, single-arm, single-site phase 1/2 pilot study.
  
  
  METHODS
  Academic referral center.
  
  
  METHODS
  A total of 23 patients, aged 37 to 79 years, having a confirmed diagnosis of leukoplakia with or without dysplasia measuring at least 10 mm in diameter.
  
  
  METHODS
  Application of 5-aminolevulinic acid to lesions followed by activation with high-power 585-nm pulsed dye laser.
  
  
  METHODS
  Maximum tolerated dose of laser, postprocedure complications, objective response to treatment, and immunohistochemical changes in treated tissue.
  
  
  RESULTS
  No significant adverse events occurred; minor local adverse effects were observed during and following photodynamic therapy in the safety phase of the study. The maximum tolerated dose was 8 J/cm(2). Of 17 patients, 7 (41%) had more than 75% regression (significant response) and 9 (53%) had more than 25% regression (partial response), for an overall response rate of 94% at 90 days. This response rate was far higher than the null-hypothesis 20% rate (P < 10(-10)) and the alternative-hypothesis 50% rate (P = .0001) for which the study was powered. When compared with baseline levels immunohistochemically, p53 expression was increased in 8 of 11 available samples (73%) and Ki-67 expression was decreased in 7 of 12 available samples (58%).
  
  
  CONCLUSIONS
  Photodynamic therapy with 5-aminolevulinic acid and pulsed dye laser could be used to achieve regression of oral leukoplakia. The treatment is safe and well tolerated. An application time of 1.5 hours and laser radiant exposure of 8 J/cm(2) with 1.5-ms pulse time were found to be the optimal settings in this study. The high-power laser used in this study allows completion of laser therapy within 1 to 3 minutes. Further studies are necessary to determine the optimal laser radiant exposure and drug application to maximize the response rate.
authors: Department of Otolaryngology, Jackson T. Stephens Spine Center, University of Arkansas for Medical Sciences, 501 Jack Stephens Drive, Little Rock, AR 72205, USA. Shafirsteingal@uams.edu
authors: Gal
authors: G
authors: Shafirstein
authors: Adva
authors: A
authors: Friedman
authors: Eric
authors: E
authors: Siegel
authors: Mauricio
authors: M
authors: Moreno
authors: Wolfgang
authors: W
authors: Bäumler
authors: Chun-Yang
authors: CY
authors: Fan
authors: Kimberly
authors: K
authors: Morehead
authors: Emre
authors: E
authors: Vural
authors: Brendan C
authors: BC
authors: Stack
authors: James Y
authors: JY
authors: Suen
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000368:Aged; D000622:Aminolevulinic Acid / Q000008:administration & dosage*; D001706:Biopsy; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053685:Laser Therapy / Q000379:methods*; D054025:Lasers, Dye / Q000627:therapeutic use*; D007972:Leukoplakia, Oral / Q000175:diagnosis / Q000188:drug therapy* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage*; D010865:Pilot Projects; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid