Daylight-mediated Photodynamic Therapy of Actinic Keratoses:Comparing 0.2%HAL With 16%MAL

Daylight-mediated Photodynamic Therapy of Actinic Keratoses: a Randomized, Double-blinded Pilot Study Comparing Topical 0.2% Hexylaminolaevulinate With 16% Methylaminolaevulinate

This pilot study compares two photosensitizers, hexylaminolaevulinate (HAL) and methylaminolaevulinate (MAL), in treatment of actinic keratoses. Study is conducted using randomized split-face design. Efficacy is assessed clinically, and histologically at 3 and 12 months. Pain during and after treatments and adverse reactions at one week are recorded.

Study recruites 16-20 voluuntering patients with symmetrical actinic damage on face or scalp. Treatment sites are randomized to receive either hexylaminolaevulinate 0.2% or methylaminolaevulinate ( 16% MAL) as photosensitizers (0.25mm-thick layer). A web-based validated program (Research Randomizer) generated a randomized list to define the treatment sides. The randomization results were kept blinded from the investigators who conducted the follow-up visits, from the pathologist, and the patients. Pre-treatment procedures include application of sunscreen for 15 minutes and curettage of the treatment area. Illumination is performed using 2 hours daylight-exposure. Efficacy is assessed clinically, and histologically at 3 and 12 months by blinded observers. Pain during and after treatments and adverse reactions at one week are recorded.

Actinic keratoses, Daylight-PDT, Hexylaminolaevulinate, HAL, Methylaminolaevulinate, MAL, Hyperspectral imaging

0.2% HAL (Hexvix, Photocure) mixed with Unguentum M (Allmiral) and MAL (Metvix, Galderma) used in a randomized split-face design

Punch biopsies were taken symmetrically on both treatment fields from equally graded >6 mm AKs prior to treatment and again at 3 months, blinded observer (pathologist). HE- and p53-stainings. Samples not fulfilling the criteria of an AK were defined as healthy or completely cleared. The p53 reactivity expressed as average percentage of positive nuclei in three consecutive high power fields from the region of highest reactivity (<10 % normal)

Adverse reactions are evaluated by blinded observer at one week after treatment. Severity of the reaction ( Redness, crusting and scaling) is assessed using grading: minimal, mild, intermediate, severe.

Pain using visual analog scale (VAS 0-10, where 0 is no pain and 10 is the worst pain imaginable) on both treatment sides is assessed in every 30 minutes during 2-hour sun-exposure and afterwards once in two hours until 9 p.m. (treatment day). Of these values, the mean maximal pain is assessed.

Inclusion Criteria: -Symmetrical actinic damage on face or scalp Exclusion Criteria: Pregnancy Lactation Allergy to photosensitizer Photodermatose

Neittaanmaki-Perttu N, Gronroos M, Karppinen TT, Tani TT, Snellman E. Hexyl-5-aminolaevulinate 0.2% vs. methyl-5-aminolaevulinate 16% daylight photodynamic therapy for treatment of actinic keratoses: results of a randomized double-blinded pilot trial. Br J Dermatol. 2016 Feb;174(2):427-9. doi: 10.1111/bjd.13924. Epub 2015 Nov 20. No abstract available.