Background: Topical photodynamic therapy (PDT) is a successful treatment for nonmelanotic skin cancers (NMSCs). Nevertheless, surgical excision continues to be the gold standard treatment. Cervicofacial excision often results in functional and aesthetic impairment. We hypothesize that topical PDT as a neoadjuvant therapy to surgical excision may reduce tumour size and subsequently decrease local morbidity.
Objective: To determine the utility of PDT in reducing the NMSC area for the purpose of surgical excision.
Method: A prospective cohort study.
Results: Thirty-three basal cell carcinomas with a mean area of 523.11 ± 120.93 mm² and 26 squamous cell carcinomas with a mean area of 357.53 ± 61.96 mm² were included. Of these lesions, 22 demonstrated a complete curative response after an average of two PDT treatments, which were then confirmed with histologically negative biopsies. The remaining lesions demonstrated a partial response to topical PDT with a maximum reduction in lesion area following an average of three PDT treatments of at least 88% (p < .05). These lesions were then excised with clear histologic margins. Follow-up at 1 year for all lesions demonstrated no locoregional recurrence.
Conclusions: This is the first study to investigate the efficacy of neoadjuvant topical PDT in the management of NMSC. The results suggest that for NMSC not demonstrating a complete curative response to PDT, neoadjuvant PDT can substantially reduce tumour burden, allowing for less morbid surgical excisions with histologically clear margins.