Topical corticosteroid reduces inflammation without compromising the efficacy of photodynamic therapy for actinic keratoses: a randomized clinical trial.

Photodynamic therapy (PDT) is an effective and established treatment for actinic keratoses (AK) and nonmelanoma skin cancer. The main side-effects of PDT are post-treatment erythema and oedema, and pain during illumination. Severe erythema after PDT enhances the down time associated with the treatment. To evaluate in a randomized intraindividual study whether use of a topical corticosteroid just before and just after PDT would reduce treatment-induced erythema compared with conventional PDT. Twenty-two patients with multiple AKs in the face and scalp were treated with methyl aminolaevulinate PDT in two symmetrical areas. One area was randomized to superpotent corticosteroid (clobetasol propionate) before and just after PDT. Objective and visual erythema, protoporphyrin IX (PpIX) fluorescence and pain were evaluated. Topical corticosteroid significantly reduced PDT-induced erythema (P = 0·012). The complete lesion response rate 3 months after PDT, and PpIX fluorescence prior to illumination did not differ significantly between the two treated areas. Superpotent corticosteroid before and just after PDT reduced the erythema 24 h after treatment of multiple AKs on the face and scalp. The use of topical corticosteroid did not affect the efficacy of PDT and may be an easy way to make PDT treatment of large visible areas more acceptable.