title: Randomized controlled trial comparing 35% trichloroacetic acid peel and 5-aminolaevulinic acid photodynamic therapy for treating multiple actinic keratosis.
abstract: BACKGROUND
  Photodynamic therapy (PDT) and chemical peels with trichloroacetic acid (TCA) can be applied to large skin areas and thus are suitable treatment options for patients with multiple actinic keratosis (AK). However, despite its long use, TCA has been investigated only rarely in this indication.
  
  
  OBJECTIVE
  This randomized, observer-blinded, intrapatient comparative study sought to investigate the efficacy and safety of 35% TCA vs. aminolaevulinic acid 20% (ALA) PDT in patients with extensive field cancerization and multiple AKs in the face or on the scalp.
  
  
  METHODS
  Twenty-eight patients with at least five AKs in two comparable anatomical areas on the head were treated with 35% TCA and ALA PDT randomly assigned to each area. Their therapeutic efficacy, adverse events and cosmetic outcome were assessed by a blinded investigator at 1, 3, 6 and 12 months after treatment.
  
  
  RESULTS
  After 12-months' follow-up TCA and ALA PDT reduced the total lesion count, the primary outcome, by 31% and 58%, respectively (P = 0·006). Complete clearance of pre-existing AKs were 49% for TCA and 74% for ALA PDT (P = 0·011). Treatment failure (number of AKs greater than 50% of the baseline count) was observed in seven patients (25%) after TCA and in two patients (7%) after PDT treatment. Treatment-related pain was significantly higher for ALA PDT (visual analogue scale 7·5 ± 2·3 vs. TCA: 5·1 ± 2·6; P = 0·04), whereas scarring (n = 6, 21%) was seen only in TCA treated patients.
  
  
  CONCLUSIONS
  ALA PDT provided better clinical results than TCA in the treatment of patients with extensive field cancerization and multiple AKs.
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, SMZ Ost, 122, Langobardenstrasse, 1220, Vienna, Austria.|Department of Dermatology, Donauspital, SMZ Ost Vienna, Vienna, Austria.|Medical Research Society Vienna DC, Vienna, Austria.
authors.forename: G
authors.initials: G
authors.lastname: Holzer
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, SMZ Ost, 122, Langobardenstrasse, 1220, Vienna, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Pinkowicz
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, SMZ Ost, 122, Langobardenstrasse, 1220, Vienna, Austria.
authors.forename: S
authors.initials: S
authors.lastname: Radakovic
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, SMZ Ost, 122, Langobardenstrasse, 1220, Vienna, Austria.
authors.forename: J B
authors.initials: JB
authors.lastname: Schmidt
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, SMZ Ost, 122, Langobardenstrasse, 1220, Vienna, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Tanew
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000622:Aminolevulinic Acid / Q000008:administration & dosage* / Q000009:adverse effects; D002424:Caustics / Q000008:administration & dosage / Q000009:adverse effects; D005148:Facial Dermatoses / Q000188:drug therapy*; D005260:Female; D006801:Humans; D055623:Keratosis, Actinic / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000139:chemically induced; D010147:Pain Measurement; D010778:Photochemotherapy / Q000379:methods; D017319:Photosensitizing Agents / Q000008:administration & dosage* / Q000009:adverse effects; D012536:Scalp Dermatoses / Q000188:drug therapy*; D016037:Single-Blind Method; D014238:Trichloroacetic Acid / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D002424:Caustics; D017319:Photosensitizing Agents; D014238:Trichloroacetic Acid; D000622:Aminolevulinic Acid