Canadian Expert Consensus Recommendations on the Use of Photodynamic Therapy in Actinic Keratosis.
Actinic keratosis (AK), a common ultraviolet light-induced keratinocyte neoplasm arising within chronically photodamaged skin, is associated with field cancerization and potential progression to cutaneous squamous cell carcinoma (cSCC). Photodynamic therapy (PDT) is an established field-directed treatment option for AK, but Canadian-specific practical guidance on its use remains limited. This study aimed to develop Canadian expert consensus recommendations on the overall role, positioning, technique, safety, follow-up, and use of PDT as well as PDT use in special sites and populations.
A targeted literature review was conducted using PubMed/MEDLINE for English-language publications from 2005 onward, with the final search run on October 10, 2025. Evidence was used to inform candidate statements across predefined PDT-related domains. Ten Canadian dermatologists with extensive experience with management of AK and use of PDT participated in a structured modified Delphi process, rating statements anonymously over two rounds using a 5-point Likert scale. Consensus was defined a priori as at least 75% agreement or strong agreement.
All 10 panelists participated in both Delphi rounds. A total of 25 consensus statements were finalized across six domains: disease framing and need for AK treatment; lesion- versus field-directed treatment strategies for AK management; role and positioning of PDT in AK management; PDT technique and modalities for AK management; PDT for AK management in special sites and populations; and PDT safety, follow-up, and combination strategies. All finalized statements achieved consensus. The panel positioned PDT as an effective field-directed strategy, particularly for non-hypertrophic facial and scalp AKs, with treatment selection guided by disease extent and the need for field cancerization with PDT; efficacy, tolerability, cosmetic outcome, and access to PDT; and patient preference for PDT.
This Canadian expert consensus supports PDT as a practical field-directed strategy for appropriately selected patients with AK, while emphasizing individualized care, shared decision-making, realistic expectations for chronic disease management, and ongoing follow-up. Further research is needed to clarify re-treatment intervals, outcomes for special sites and populations, and optimal combination strategies.
A targeted literature review was conducted using PubMed/MEDLINE for English-language publications from 2005 onward, with the final search run on October 10, 2025. Evidence was used to inform candidate statements across predefined PDT-related domains. Ten Canadian dermatologists with extensive experience with management of AK and use of PDT participated in a structured modified Delphi process, rating statements anonymously over two rounds using a 5-point Likert scale. Consensus was defined a priori as at least 75% agreement or strong agreement.
All 10 panelists participated in both Delphi rounds. A total of 25 consensus statements were finalized across six domains: disease framing and need for AK treatment; lesion- versus field-directed treatment strategies for AK management; role and positioning of PDT in AK management; PDT technique and modalities for AK management; PDT for AK management in special sites and populations; and PDT safety, follow-up, and combination strategies. All finalized statements achieved consensus. The panel positioned PDT as an effective field-directed strategy, particularly for non-hypertrophic facial and scalp AKs, with treatment selection guided by disease extent and the need for field cancerization with PDT; efficacy, tolerability, cosmetic outcome, and access to PDT; and patient preference for PDT.
This Canadian expert consensus supports PDT as a practical field-directed strategy for appropriately selected patients with AK, while emphasizing individualized care, shared decision-making, realistic expectations for chronic disease management, and ongoing follow-up. Further research is needed to clarify re-treatment intervals, outcomes for special sites and populations, and optimal combination strategies.
Authors
Prajapati Prajapati, Richer Richer, Sander Sander, Devani Devani, Abdulla Abdulla, Sauder Sauder, Nigen Nigen, Litvinov Litvinov, Lynde Lynde, Rao Rao
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