Photodynamic therapy in lung cancer. A review

PDT utilizes photosensitizing agents that are selectively retained by tumors. These agents have high resulting tumor:tissue concentrations but are inactive by themselves. When activated by light, they generate free radicals, resulting in membrane injury, vascular injury, and immune-mediated injury with relatively selective cytotoxicity to tumor cells. Clinically, PDT can be used to treat CIS as well as more advanced lung cancers with endobronchial obstruction. PDT should be viewed as one tool of many that can be used to deal with airway problems in patients with lung cancer and it will often need to be used in conjunction with other techniques, such as airway stenting, Nd-YAG, or cryotherapy. For PDT to be effective, it must be integrated into a multimodality approach, including chemotherapy and radiation therapy.