Evaluating the safety and efficacy of aminolevulinic acid 20% topical solution activated by pulsed dye laser and blue light in the treatment of facial cutaneous squamous cell carcinoma in situ

Squamous cell carcinoma (SCC) is the second most common cutaneous malignancy, after basal cell carcinoma (BCC). Photodynamic therapy (PDT) involves converting a photosensitizer to reactive oxygen intermediates, which preferentially bind to hyperproliferative tissue. The most commonly used photosensitizers are methyl aminolevulinate and aminolevulinic acid (ALA). Presently, ALA-PDT is approved in the US and Canada for the treatment of actinic keratoses on the face, scalp, and upper extremities.This cohort study evaluated the safety, tolerability, and efficacy of aminolevulinic acid, pulsed dye laser, and photodynamic therapy (ALA-PDL-PDT) for treatment of facial cutaneous squamous cell carcinoma in situ (isSCC).Twenty adult patients with biopsy-confirmed isSCC on the face were recruited. Only lesions 0.4-1.3 cm in diameter were included. Patients underwent two treatments with ALA-PDL-PDT spaced 30 days apart. The isSCC lesion was then excised 4-6 weeks following the second treatment for histopathological assessment.No residual isSCC was detected in 17/20 (85%) patients. Two of the patients with residual isSCC had skip lesions present that explained the treatment failure. Excluding the patients with skip lesions, the posttreatment histological clearance rate was 17/18 (94%). Minimal side effects were reported.Our study was limited by small sample size and lack of long-term recurrence data.The ALA-PDL-PDT protocol is a safe and well-tolerated treatment option for isSCC on the face, providing excellent cosmetic and functional results.