title: Evaluation of the chemopreventative effects of ALA PDT in patients with multiple actinic keratoses and a history of skin cancer.
abstract: BACKGROUND
  Actinic keratoses (AKs) are in situ epidermal tumors that may progress to invasive squamous cell carcinomas (SCCs). Aminolevulinic acid with photodynamic therapy (ALA PDT) is a field treatment for AK.
  
  
  OBJECTIVE
  To evaluate the time to development of new non-melanoma skin cancers (NMSC) within one year of ALA-PDT treatment in immunocompetent patients with AK and a history of skin cancer.
  
  
  METHODS
  One hundred forty anatomic sites in 114 patients were treated with topical ALA for a 1 to 3 hour incubation period followed by photodynamic therapy (PDT) with a blue light. All new NMSCs within the treatment areas were recorded over a 1-year observational period.
  
  
  RESULTS
  Eighty-three anatomic sites (59%) did not develop new skin cancers within 1 year. Additionally, 92%, 78%, and 64% of anatomic sites were free of new skin cancers at 3, 6, and 9 months after treatment was initiated. Although approximately 41% of patients treated on both the scalp and face developed new skin cancers within 1 year of treatment, the average time to develop skin cancer was longer for the face (7.09 months) than for the scalp (5.34 months).
  
  
  CONCLUSIONS
  In patients with a history of NMSC and multiple AKs, ALA PDT may be a valuable option for the prevention and delay of new NMSCs.
authors.affiliation: Derm Surgery Associates, Houston, TX, USA. goldb1@dermsurgery.org
authors.forename: Leonard H
authors.initials: LH
authors.lastname: Goldberg
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Landau
authors.forename: Megan N
authors.initials: MN
authors.lastname: Moody
authors.forename: Denise
authors.initials: D
authors.lastname: Marquez
authors.forename: Ming
authors.initials: M
authors.lastname: Jih
authors.forename: Arash
authors.initials: A
authors.lastname: Kimyai-Asadi
authors.forename: Paul M
authors.initials: PM
authors.lastname: Friedman
authors.forename: Angie
authors.initials: A
authors.lastname: Busch
authors.forename: Irene J
authors.initials: IJ
authors.lastname: Vergilis-Kalner
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000622:Aminolevulinic Acid / Q000008:administration & dosage*; D005153:Facial Neoplasms / Q000517:prevention & control; D005260:Female; D005500:Follow-Up Studies; D006258:Head and Neck Neoplasms / Q000517:prevention & control; D006801:Humans; D055623:Keratosis, Actinic / Q000150:complications / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage; D012878:Skin Neoplasms / Q000517:prevention & control*; D013997:Time Factors
chemical_list: D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid