(HealthDay News) – A two-step irradiance protocol with topical δ-aminolevulinic acid (ALA) and photodynamic therapy (PDT) minimizes pain while maintaining comparable clinical outcomes for the treatment of non-melanoma skin cancer lesions, according to a study published online Feb. 6 in Lasers in Surgery and Medicine.

Nathalie C. Zeitouni, MDCM, from the Roswell Park Cancer Institute in Buffalo, NY, and colleagues reviewed the clinical experience of ALA-PDT use in 14 Caucasian patients: nine men and five women, ages 18–80 years, with a total of 51 superficial and 73 nodular basal cell carcinomas (BCCs) and three Bowen’s disease lesions. Each lesion received ALA for approximately four hours, receiving an initial irradiance of 30–50mW/cm² for 20J/cm², followed by 150mW/cm², for a total fluence of 200–300J/cm². A visual analog scale (VAS) was used to assess pain. At six–12 months, clinical outcome was determined.

The researchers found that for both irradiances the median VAS scores were 1.0. Xylocaine (1%) was required for pain control in five of 127 lesions. Lesion location strongly influenced pain, while lesion type, number, and size did not. Of the BCCs, 84.1% achieved complete responses, which compared favorably with reported results for single ALA-PDT treatments. A complete response was also seen in two of three Bowen’s disease lesions and in 37% of nodular BCCs, which were also within the range of reported outcomes.

“In conclusion, we have validated a simple approach to minimize the pain experienced by patients undergoing topical ALA-PDT for cutaneous cancers,” the authors write. “We conclude that the protocol offers significant benefit to patients.”

Full Text (subscription or payment may be required)