Studies have shown that photodynamic therapy (PDT) causes or enhances an antitumor immune response. Moving from a mouse model in lung cancer to a translational approach, researchers are conducting an ongoing observational study to determine whether the immune response in patients with lung cancer treated with PDT is mediated by a T-cell phenotype, which may result in decreased tumor size and potentially improve survival. Preliminary findings focus on certain inflammatory cytokines that may be predictive of these T-cell phenotypes, such as interleukin ( Bruce shared the very early findings of her current study to determine whether the immune response in patients with non-small cell lung cancer (NSCLC) treated with PDT is T-cell mediated. She briefly explored the ongoing journey to clarify the immunologic response of PDT in patients with lung cancer in the hope of optimizing the ability to predict patient outcomes and translating the defined immune profile of PDT treatment in lung cancer into effective therapeutic interventions.One review served as a background for the rationale behind exploring the immunologic consequences of PDT in cancer treatment.1 van Duijnhoven et al. 1 addressed the effect of PDT on the immune response in patients with solid tumors. They suggested that through destroying the structure of a tumor, PDT enables direct interaction between immune cells and tumor cells; this type of "in situ vaccination" induces a systemic antitumor immune response. Another retrospective review (coauthored by Dr. Moffatt-Bruce's colleague and mentor Dr. Patrick Ross) 2 focused on the incorporation of PDT into the induction therapy regimen for locally advanced primary nonmetastatic NSCLC bronchogenic carcinoma. Fifty percent of patients initially deemed unresectable were able to undergo definitive surgical resection after trimodality induction therapy consisting of PDT with chemotherapy and/ or irradiation.2 In addition, 27% of patients considered to require pneumonectomy were able to have a lobectomy after trimodality induction therapy.2 Finally, the pathologic stage was less than the preinduction clinical stage in 14 of 22 cases, of which 4 patients had no residual tumor.2