In previous studies, we synthesized a PD-L1-targeted molecular probe, ⁶⁸Ga-DPA, and developed a ⁶⁸Ga-DPA injection for clinical research. Preliminary studies demonstrated its favorable safety profile and excellent imaging performance. Leveraging the established strengths of the Department of Nuclear Medicine at Peking Union Medical College Hospital, we now plan to conduct an exploratory PET/CT imaging study in lung cancer patients. This study aims to provide an in vivo, non-invasive, and visualizable technique for detecting PD-L1 expression levels and spatial distribution in tumors. It will further validate the clinical utility of this technology, offering critical diagnostic insights for initial assessment and treatment efficacy evaluation in PD-L1-positive tumor patients undergoing PD-L1-targeted therapies.