Photodynamic therapy is more effective than imiquimod for actinic keratosis in organ transplant recipients - a randomized intra-individual controlled trial.Togsverd-Bo K, Halldin C, et al.
British Journal of Dermatology 2017 [Epub ahead of print]
To compare the efficacy and safety of treatment for actinic keratoses (AKs) in solid organ transplant recipients (OTRs) with methyl aminolevulinate photodynamic therapy (MAL-PDT) versus imiquimod (IMIQ).
Patients were randomized to treatment areas of MAL-PDT or IMIQ. All patients received one treatment of MAL-PDT and one of IMIQ at baseline and were seen at 1, 2 and 3 months.
35 OTRs aged > 18 years with clinically diagnosed AKs in two similar areas on the face, scalp, dorsal hands or forearms, fitzpatrick skin types I-III and stable graft function.
The primary outcome measured was complete response. Secondary outcomes measured were new AK lesions in each study area, skin reactions, pain or discomfort during treatment, laboratory values, cosmetic outcome and treatment preference.
This small, well-designed study from Sweden investigates the treatment of actinic keratosis, a premalignant skin-change, in organ transplant recipients. Transplant recipients with actinic keratosis were treated with both photodynamic therapy and imiquimod in different body areas, to allow comparison of efficacy within the same patient. The authors demonstrate a higher response rate with photodynamic therapy, although it was associated with more skin reaction and pain than imiquimod. Outcome assessors were blinded to treatment areas, reducing risk of assessment bias for response rate. However, patients were not blinded meaning that patient reported outcomes may be prone to bias. The authors highlight the possibility of treatment contamination due to systemic effects, as both treatments were used at the same time in different body areas. However, this design has the advantage of reducing variability in response between patients allowing for a smaller sample size.