Current state and future of photodynamic therapy for the treatment of head and neck squamous cell carcinoma

Photodynamic therapy has shown promise in the treatment of early head and neck squamous cell carcinoma (SCC). In photodynamic therapy (PDT), a light sensitive drug (photosensitizer) and visible light cause cancer cell death by the creation of singlet oxygen and free radicals, inciting an immune response, and vascular collapse. In this paper, we review several studies that demonstrate the effectiveness of PDT in the treatment of early stage SCC of the head and neck, with some showing a similar response rate to surgery. Two cases are presented to illustrate the effectiveness of PDT. Then, new advances are discussed including the discovery of STAT3 crosslinking as a potential biomarker for PDT response and interstitial PDT for locally advanced cancers.