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.

Background: 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.

Aims: 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).

Methods: 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.

Results: 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.

Limitations: Our study was limited by small sample size and lack of long-term recurrence data.

Conclusions: The ALA-PDL-PDT protocol is a safe and well-tolerated treatment option for isSCC on the face, providing excellent cosmetic and functional results.