Intensified fractional CO 2 laser‐assisted photodynamic therapy vs. laser alone for organ transplant recipients with multiple actinic keratoses and wart‐like lesions: a randomized half‐side comparative trial on dorsal hands

Summary Background Photodynamic therapy ( PDT ) is a well‐documented treatment for actinic keratosis ( AK ), but achieves inferior efficacy in organ transplant recipients ( OTR s), particularly in acral regions. Ablative fractional laser ( AFXL ) intensifies the PDT response and may improve the efficacy of AK clearance when used as monotherapy. Objectives To compare the efficacy of a single treatment with AFXL ‐assisted PDT vs. AFXL alone for difficult‐to‐treat AK s and wart‐like lesions ( WLL s) in OTR s. Methods Ten OTR s were included with a total of 680 AK s (severity grade I– III ) and 409 WLL s on the dorsal hands. Both hands were initially treated with targeted fractional ablation of thick keratotic lesions followed by AFXL field treatment. Treatment regions were then randomized to (i) PDT ( AFXL ‐ PDT ) or (ii) no further treatment ( AFXL ). The primary end point was complete response ( CR ) at 4 months after treatment; secondary end points were improvement of AK severity grade, overall patient assessment of efficacy and tolerability of treatments. Results CR of AK s was significantly higher for AFXL ‐ PDT (73%) compared with AFXL alone (31%) ( P  =   0·002). AFXL ‐ PDT improved 82% of AK s to lower lesion grades compared with 52% after AFXL alone ( P  =   0·008). For WLL s, the rate of CR was 37% for AFXL ‐ PDT compared with 14% for AFXL ( P  =   0·02). Overall assessment showed a preference for AFXL ‐ PDT compared with AFXL ( AFXL ‐ PDT , n  =   8; AFXL , n  =   0; equal, n  =   2). Mild pigment changes were observed in four patients ( AFXL ‐ PDT , n  =   3; AFXL , n  =   1). No scarring was observed. Conclusions AFXL ‐ PDT is more effective than AFXL in the treatment of acral AK s and WLL s in OTR s.