High and sustained efficacy after two sessions of topical 5-aminolaevulinic acid photodynamic therapy for basal cell carcinoma: a prospective, clinical and histological 10-year follow-up study.

BACKGROUND

Prolonged follow-up data on topical photodynamic therapy (PDT) in basal cell carcinoma (BCC) are necessary for a full evaluation of its effect and for comparison with conventional treatment methods.

OBJECTIVES

To assess 10-year long-term PDT efficacy in primary and recurrent BCC and to evaluate clinical and histopathological factors which may be associated with treatment failure.

METHODS

We performed a longitudinal study on 60 histologically verified BCCs in 44 patients treated with curettage and one or two sessions of dimethylsulphoxide (DMSO)-supported topical 5-aminolaevulinic acid (ALA)-based PDT. Treated lesions were investigated by clinical and histopathological examination at regular intervals. The main outcomes were 10-year lesion complete response rate using a time-to-event analysis, histological treatment failure and cosmesis.

RESULTS

Overall complete response rate for all lesions was 75% (95% confidence interval 64-87%); 60% after one and 87% after two treatment sessions. The response rate was 78% for primary lesions; 63% after one and 90% after two sessions. The cosmetic outcome was rated as good or excellent in 91-100% of evaluated cases. Treatment failure was documented in 15 (25%) of 60 lesions; clinical investigation identified 14 of them. All failures were noted within 3 years of treatment. Male gender, recurrent tumour and one treatment session were factors significantly associated with treatment failure. The only lesion larger than 2·0 cm relapsed.

CONCLUSIONS

Two sessions of DMSO-supported topical ALA-PDT and curettage can provide long-term effective treatment results with favourable cosmetic outcome in primary, small BCC.