Development and evaluation of a low-cost, portable, LED-based device for PDT treatment of early-stage oral cancer in resource-limited settings.

BACKGROUND: Photodynamic therapy (PDT) using δ-aminolevulinic acid (ALA) photosensitization has shown promise in clinical studies for the treatment of early-stage oral malignancies with fewer potential side effects than traditional therapies. Light delivery to oral lesions can also carried out with limited medical infrastructure suggesting the potential for implementation of PDT in global health settings. OBJECTIVES: We sought to develop a cost-effective, battery-powered, fiber-coupled PDT system suitable for intraoral light delivery enabled by smartphone interface and embedded electronics for ease of operation. METHODS: Device performance was assessed in measurements of optical power output, spectral stability, and preclinical assessment of PDT response in ALA-photosensitized squamous carcinoma cell cultures and murine subcutaneous tumor xenografts. RESULTS: The system achieves target optoelectronic performance with a stable battery-powered output of approximately 180 mW from the fiber tip within the desired spectral window for PpIX activation. The device has a compact configuration, user friendly operation and flexible light delivery for the oral cavity. In cell culture, we show that the overall dose-response is consistent with established light sources and complete cell death of ALA photosensitized cells can be achieved in the irradiated zone. In vivo PDT response (reduction in tumor volume) is comparable with a commercial 635 nm laser. CONCLUSIONS: We developed a low-cost, LED-based, fiber-coupled PDT light delivery source that has stable output on battery power and suitable form factor for deployment in rural and/or resource-limited settings. Lasers Surg. Med. 9999:1-7, 2018. © 2018 Wiley Periodicals, Inc.