Photodynamic therapy using topical methyl 5-aminolevulinate compared with cryotherapy for actinic keratosis: A prospective, randomized study

J Am Acad Dermatol. 2002 Aug;47(2):258-62.


Background: Actinic keratoses (AKs) are the most common premalignant tumors. Without treatment, a significant number of patients with AK will experience squamous cell carcinoma. Photodynamic therapy (PDT) using the new highly selective photosensitizer methyl 5-aminolevulinate is a promising new treatment modality for AK.

Objective: We investigated the complete response rates, cosmetic outcome, and patient satisfaction after photodynamic therapy (PDT) using methyl 5-aminolevulinate (Metvix) versus cryotherapy in the treatment of AKs.

Methods: Patients were randomized to receive either cryotherapy with liquid nitrogen spray or PDT using methyl 5-aminolevulinate cream 160 mg/g, 3 hours application time, and red light (75 J/cm(2)).

Results: Efficacy results from 193 patients with 699 lesions (92% face/scalp and 93% thin/moderately thick) were analyzed. Overall complete response rates after 3 months were 69% for PDT and 75% for cryotherapy. Both treatments gave higher response rates in thin lesions (PDT 75%, cryotherapy 80%). PDT gave better cosmetic results and higher patient satisfaction than cryotherapy.

Conclusion: PDT using methyl 5-aminolevulinate is an attractive treatment option for patients with AK, with a response rate similar to that of cryotherapy, but with superior cosmetic results and high patient satisfaction.

Publication types

  • Clinical Trial
  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Topical
  • Adult
  • Aged
  • Aged, 80 and over
  • Aminolevulinic Acid / administration & dosage
  • Aminolevulinic Acid / analogs & derivatives
  • Aminolevulinic Acid / therapeutic use*
  • Cryotherapy*
  • Female
  • Humans
  • Keratosis / drug therapy*
  • Male
  • Middle Aged
  • Photochemotherapy*
  • Photosensitizing Agents / administration & dosage
  • Photosensitizing Agents / therapeutic use*
  • Prospective Studies
  • Treatment Outcome


  • Photosensitizing Agents
  • methyl 5-aminolevulinate
  • Aminolevulinic Acid