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.

Bowen's disease on finger: A diagnostic and therapeutic challenge.

Bowen's disease commonly presents as a solitary asymptomatic plaque involving head and neck region or lower limbs. We present a case of a sixty seven-year-old man with an itchy, oozy, crusted solitary plaque on the right ring finger of eighteen months duration with histopathology consistent with Bowen's disease. The lesion was initially treated with topical 5% imiquimod but due to relapse and inadequate response to a second course, complete surgical excision followed by full thickness skin grafting was done. Recurrence after about 6 months in the form of a small papule adjacent to the initial site was also treated with excision. This report highlights the potential of Bowen's disease to mimic more common dermatoses and a high index of suspicion, supported by histopathology, is required to diagnose and treat it without delay, which in turn may require a multimodality approach. We also reviewed the current literature on the same.

Photodynamic therapy in dermatology.

Photodynamic therapy is a new modality of therapy being used for the diagnosis and treatment of many tumors. It is now being increasingly used for skin tumors and other dermatological disorders. With its range of application it is certainly the therapy of the future. Its mechanism of action is by the Type II photo-oxidative reaction. The variables are the photosensitizer, the tissue oxygenation and the light source. It has been used to treat various disorders including Bowen's disease, actinic keratoses, squamous cell carcinomas, basal cell carcinomas, and mycosis fungoides. The side-effects are fortunately mild and transient. Newer photosensitizers like methyl aminolevulinate hold a lot of promise for better therapy.

Terapia fotodinámica en queratosis actíicas y en enfermedad de Bowen (comunicación preliminar) / Photodynamic therapy in actinic keratoses and Bowen's disease: preliminary report

La Terapia Fotodinámica(TFD) tópica ha sido usada en un gran número de patologías dermatológicas benignas y malignas. Está particularmente indicada en Queratosis Actínicas (QA) y en Enfermedad de Bowen (EB). Consiste en la aplicación tópica de ácido aminolevulínico (ALA) que se transforma a nivel celular en protoporfirina IX (un poderoso fotosensibilizante) y se aplica sobre las lesiones malignas o premalignas, las que luego se fotosensibilizan. Posteriormente, las lesiones blanco son irradiadas con una luz láser (generalmente una luz roja) y las lesiones son destruidas por oxidación. Para evaluar la eficacia y la seguridad de la terapia, nosotros diseñamos un protocolo, que incluye a 5 pacientes con QA y dos con EB. Los diagnósticos clínicos son confirmados con biopsias y se toma iconografía previa al tratamiento y al final del mismo. Dos meses después de la segunda sesión de TFD se toma la biopsia de control. El tratamiento consiste en la aplicación de ALA al 20 por ciento (Levulan KerastickM.R.) sobre las lesiones blanco seleccionadas. Después de 14 horas, las lesiones son irradiadas con un láser que tiene una longitud de onda de 100 J/cm2 y 140 mW/cm2. Los paciente se controlan a los 3,7, 30 y 60 días. El tratamiento se repite a los 60 días de la primera sesión usando las mismas dosis mencionadas anteriormente. Hasta la fecha sólo dos pacientes han completado el tratamiento y éstos son los casos aquí presentados. Los resultados del paciente con EB han demostrado una remisión clínica superior al 90 por ciento. La biopsia de control de éste demostró una epidermis normal sin signos de displasia. El paciente con QA presentó una completa remisión clínica e histológica luego de dos sesiones de TFD. En relación a los resultados de esta experiencia preliminar, la TFD nos parece una alternativa efectiva y segura para el tratamiento de QA y EB.