In photodynamic therapy, light from a laser enhanced by photosensitizing agents, can kill cancer cells without damage to normal cells. The basic technique is over 50 years old but the past 5 years have seen the development of reliable, portable lasers and better photosensitizing agents. These advances have made the technique quick, effective, and relatively free from side-effects. For patients with head and neck cancer, functional outcomes with photodynamic therapy are probably better than surgery and radiation therapy. However, there is inadequate long-term survival data at this time.The outcomes and survival rates of two clinical studies with photodynamic therapy compare favorably with published survival rates for surgery and/or radiotherapy for similar patients, though no comparative studies have been performed. In these studies, photodynamic therapy with temoporfin (Foscan) completely cleared cancers at 12 weeks in 83% of 115 patients with primary head and neck cancers. The one-year survival rate was 87%. This approach was also successful for 50% of 96 patients with recurrent or second primary cancers with a one year survival of 65%.An advantage of photodynamic therapy is that it can usually be given to outpatients under local anesthesia. Patients receive intravenous temoporfin, followed 4 days later by brief laser illumination of the cancer site. About 10% of some 1000 patients treated worldwide had photosensitivity reactions – mostly only mild erythema. Photosensitivity takes 2–3 weeks to resolve, during which time patients must avoid bright light. There was also significant post-treatment pain, which can require pain medication with opiates.Photodynamic treatment may also be of palliative benefit in more than 50% of patients with incurable head and neck cancers with complete local cancer control.
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