Treatment of superficial basal cell carcinoma by topical photodynamic therapy with fractionated 5‐aminolaevulinic acid 20% vs. two‐stage topical methyl aminolaevulinate: results of a randomized controlled trial

Summary Background Basal cell carcinoma ( BCC ) is the most common type of skin cancer and incidence rates are increasing. Photodynamic therapy ( PDT ) is a frequently used treatment, especially for superficial BCC ( sBCC ). Two topical photosensitizing agents are currently used to treat sBCC , namely 5‐aminolaevulinic acid ( ALA ) and its ester, methyl aminolaevulinate ( MAL ). Previous research showed a high efficacy for ALA ‐ PDT using a twofold fractionated illumination scheme in which two light fractions of 20 J cm −2 and 80 J cm −2 were delivered 4 h and 6 h after ALA application. Objectives To evaluate whether twofold ALA ‐ PDT is superior to conventional MAL ‐ PDT for sBCC . Methods We performed a single‐blind, randomized, multicentre trial in the Netherlands. Results Overall, 162 patients were randomized either to conventional MAL ‐ PDT or twofold ALA ‐ PDT . After 12 months, a total of six treatment failures occurred following ALA ‐ PDT and 13 treatment failures occurred following MAL ‐ PDT . The 12‐month cumulative probability of remaining free from treatment failure was 92·3% [95% confidence interval ( CI ) (83·7–96·5)] for ALA ‐ PDT and 83·4% (95% CI 73·1–90·0) for MAL ‐ PDT ( P = 0·091). Conclusions The twofold ALA ‐ PDT scheme resulted in fewer recurrences, although the difference between both treatment groups was not statistically significant. However, ALA ‐ PDT resulted in higher pain scores and more post‐treatment side‐effects compared with MAL ‐ PDT .