A Randomized Trial of Broad Area ALA-PDT for Field Cancerization Mitigation in High-Risk Patients

Area of Science:

• Dermatology
• Oncology
• Photomedicine

Background:

• Actinic keratoses (AKs) are precursors to nonmelanoma skin cancers (NMSCs).
• Patients with field cancerization face a high risk of developing new skin lesions.
• Effective treatments are needed to prevent AK progression and new NMSC formation.

Purpose of the Study:

• To assess the efficacy of aminolevulinic acid–photodynamic therapy (ALA-PDT) in reducing AK occurrence.
• To evaluate the long-term impact of ALA-PDT on lesion recurrence in high-risk patients.

Main Methods:

• A randomized, evaluator-blinded, 52-week study involving 166 patients with facial AKs.
• Patients received either 2 or 3 ALA-PDT treatments or vehicle (VEH)-PDT, with a 1-hour incubation period.
• Cryotherapy was administered at screening prior to PDT sessions.

Main Results:

• Significantly fewer patients in ALA-PDT groups (36.0% for 2x, 37.5% for 3x) were AK-free at 52 weeks compared to the VEH group (18.9%).
• Lesion recurrence rates at 52 weeks were lower for ALA-PDT (7.7% and 6.1%) versus VEH (15.5%).
• ALA-PDT, particularly 3x, demonstrated a significant reduction in NMSC development (5 lesions) compared to VEH (12 lesions).

Conclusions:

• Two or three ALA-PDT treatments with a 1-hour incubation effectively reduce AK occurrence in high-risk patients over one year.
• ALA-PDT is a well-tolerated treatment option for managing AKs and preventing NMSC development.
• The study confirms ALA-PDT's role in managing field cancerization and reducing the burden of NMSCs.