Efficacy of PDD-guided tumor excision combined with photodynamic therapy in cutaneous squamous cell carcinoma

Photodiagnosis Photodyn Ther. 2025 Jan 1:104469. doi: 10.1016/j.pdpdt.2024.104469. Online ahead of print.

Abstract

Background: Cutaneous squamous cell carcinoma (cSCC) is an aggressive tumor with unclear margins. Photodynamic diagnosis (PDD) enables the differentiation of tumor tissue from normal tissue via visible fluorescence. Photodynamic therapy (PDT) is widely used in the treatment of non-melanoma skin tumors. This study aims to illustrate the efficacy and safety of PDD-guided tumor excision combined with ALA-PDT in patients with cSCC.

Methods: This study involved 23 cSCC patients, randomly assigned to the PDD group (n=11) and the non-PDD group (n=12). Patients in the PDD group underwent tumor excision guided by PDD, while those in the non-PDD group received wide local excision (WLE). Both groups were subjected to frozen section analysis, and PDT was applied during and post-surgery.

Results: The negative margin rate in the PDD group was 98.6%, significantly higher than the 69.2% observed in the non-PDD group. The PDD group required fewer frozen section analyses and experienced reduced surgical duration.

Conclusions: PDD effectively delineates tumor margins in cSCC, guiding the scope of surgical excision. The integration of PDD-guided resection with PDT offers a highly safe and effective therapeutic strategy for cSCC.

Keywords: Aminolevulinic acid; Cutaneous squamous cell carcinoma; Photodynamic diagnosis; Photodynamic therapy; Skin tumor.