2ⁿᵈ Edition of the Cancer R&D World Conference 2026

Abstract

Introduction: Photodynamic therapy (PDT) promotes wound healing; however, its clinical use has not been investigated in humans for radiation-induced skin ulcers.

Methods and Materials: We documented the first Canadian in-human case and searched the PubMed literature using “PDT" and "radiation" and "ulcer" terms.

Results: PDT has been used to disinfect caries dentin prior to restoration, disinfecting oral tissues before or during surgical procedures, treating denture stomatitis, and treating oral candidiasis in immunocompromised patients. Radiation-induced ulcers are difficult to treat. Our team treated a chronic chest wall ulcer of five years' duration, which developed after mastectomy and adjuvant radiotherapy. Six laboratory studies involving a total of 95 rats reported an overall healing efficacy of 90% for radiation-induced skin ulcers. In our case, we applied topical 5-aminolevulinic acid (5-ALA), which was activated by red light (wavelength 630 nm) after five hours of incubation. The schema used was three 30-minute treatments at months 0, 1, 5, which can vary depending on response. Compared to hyperbaric oxygen therapy (HBOT), Photodynamic therapy (PDT) is non-invasive and has fewer complications, like skin irritation or swelling, which rarely require steroid treatment, and less photosensitivity and retinal damage. PDT is cheaper: 5-ALA costs only CAN$500 per session for Metvix (methyl 5-ALA, currently approved by Health Canada), whereas HBOT requires 30 sessions, costing about CAN$15,000. The PDT procedure is an emerging therapeutic modality for dentists, as it is simple and safe.

Conclusions: Laboratory publications substantiate the efficacy of PDT on radiation-induced skin ulcer healing. The first Canadian clinical case was documented by us. It is cost-effective, with growing  potential applications for treatment of radiation-induced cutaneous ulcers.