A follow-up study of recurrence and cosmesis in completely responding superficial and nodular basal cell carcinomas treated with methyl 5-aminolaevulinate-based photodynamic therapy alone and with prior curettage

Background Methyl 5-aminolaevulinate (mALA) is an ester derivative of 5-aminolaevulinic acid (ALA) with increased lipophilicity compared with ALA. Objectives To assess long-term cure rate, cosmesis, recurrence rate and extent of fibrosis after mALA-based photodynamic therapy (PDT) of superficial and nodular basal cell carcinomas (BCCs) showing early complete response to treatment. Methods Of 350 BCCs treated, 310 responded completely. These were in 59 patients who were followed for 2-4 years (mean 35 months) after mALA-PDT. Nodular tumours were curetted before PDT, and mALA 160 mg g(-1) was applied to all tumours for 24 h or 3 h before illumination from a broad-band halogen light source with light doses from 50 to 200 J cm(-2). Fibrosis was assessed histologically in 23 biopsies. Results The overall cure rate for 350 BCCs, including non-responders and recurrences was 79%. Of 310 lesions, 277 (89%) remained in complete response, and the cosmetic outcome was excellent or good in 272 of the completely responding lesions (98%). Histological examination showed dermal fibrosis in one of 23 biopsies. Conclusions We conclude that mALA-based PDT with prior curettage of nodular lesions is a promising new method for the treatment of BCC.