Long-term recurrence of nonmelanoma skin cancer after topical methylaminolevulinate photodynamic therapy in a dermato-oncology department

Abstract: BACKGROUND: Most available studies on the efficacy of topical photodynamic therapy focus on short-to medium-term results. Long-term data are scarce. OBJECTIVE: To evaluate the long-term efficacy of photodynamic therapy with topical methylaminolevulinate to treat Bowen's disease and basal cell carcinoma in the clinical practice setting of a dermato-oncology department. METHODS: The study included patients diagnosed with Bowen's disease or basal cell carcinoma, and who received photodynamic therapy from 2004 to 2008. Treatment protocol and clinical follow-up were standardized. The primary endpoint was clinically observed recurrence in a previous photodynamic therapy-treated area. Descriptive and survival analyses were performed. RESULTS: A total of 31 Bowen's disease lesions and 44 superficial basal cell carcinoma were treated, with a median follow-up of 43.5 months. Recurrence was observed in 14 Bowen's disease lesions (53.8%) and in 11 superficial basal cell carcinoma (33.3%). Significantly higher estimates for recurrence rates were found in patients with Bowen's disease (p=0.0036) or those aged under 58 years (p=0.039). The risk of recurrence was higher in patients with Bowen's disease than in those with superficial basal cell carcinoma and younger patients. CONCLUSIONS: Recurrence should be considered when choosing to treat non-melanoma skin cancer with photodynamic therapy. Younger age and Bowen's disease were independent predictors for long-term recurrence, suggesting the need to establish an extended period of follow-up for this subset of patients.

Terapêutica fotodinâmica com ácido delta-aminolevulínico e luz de diodos em ceratoses actínicas / Photodynamic therapy with delta-aminolevulinic acid and light-emitting diodes in actinic keratosis

FUNDAMENTOS: A terapêutica fotodinâmica é técnica de tratamento em que se aplica uma substância fotossensibilizante nos tecidos ativada por uma fonte de luz de comprimento de onda específico, gerando destruição celular seletiva. Estudam-se novas fontes de luz que possam ser usadas no tratamento de ceratoses actínicas. OBJETIVOS: Avaliar a efetividade da terapêutica fotodinâmica com ácido delta-aminolevulínico utilizando como fonte de luz um aparelho emissor de luz de diodos no tratamento de ceratoses actínicas de face e membros superiores. MÉTODOS: Dezoito pacientes com ceratoses actínicas na face ou membros superiores realizaram uma aplicação de creme de ácido delta-aminolevulínico a 20 por cento e foram submetidos à exposição de luz de diodos, comprimento de onda de 630 nm. RESULTADOS: Foram tratadas 328 ceratoses actínicas, obtendo-se cura clínica completa em 210 (64,0 por cento) após 24 semanas. Lesões do dorso das mãos apresentaram cura clínica completa em 49,2 por cento; nas demais áreas esse valor foi de 81,4 por cento. Não houve registro de efeitos adversos graves, e obteve-se bom grau de satisfação dos pacientes com os resultados. CONCLUSÃO: A terapêutica fotodinâmica com fonte de emissão de luz de diodos mostrou-se eficaz e bem tolerada para tratamento de ceratoses actínicas, com resultados semelhantes aos encontrados na literatura utilizando outras fontes luminosas.

BACKGROUND: Photodynamic therapy is a form of treatment in which a photosensitizing substance is applied to tissue and activated by a light source at a specific wavelength, thus selectively destroying cells. New light sources are being evaluated for use in the treatment of actinic keratoses. OBJECTIVES: To evaluate the efficacy of photodynamic therapy with delta-aminolevulinic acid using a light emitting diode device as a light source in the treatment of actinic keratoses of the face and upper limbs. METHODS: Eighteen patients with actinic keratoses of the face or upper limbs received an application of a 20 percent delta-aminolevulinic acid cream and were submitted to diode light irradiation at a wavelength of 630 nm. RESULTS: A total of 328 actinic keratoses were treated, obtaining complete cure in 210 (64.0 percent) after 24 weeks. Lesions situated on the back of the hands were clinically cured in 49.2 percent of cases compared to 81.4 percent in the cases of lesions in other areas. There was no record of any severe adverse effects and patient satisfaction with the results was high. CONCLUSION: Photodynamic therapy with a diode light emitting source proved effective and well-tolerated for the treatment of actinic keratoses, with results similar to those reported in the literature with other light sources.