Clinical Application of PET Imaging Targeting CLDN18.2 in Malignant Tumors

The project aims to perform integrated PET/MR or PET/CT imaging in patients with histologically confirmed or clinically suspected gastric cancer, pancreatic cancer, cholangiocarcinoma, or other malignant tumors with high Claudin18.2 (CLDN18.2) expression, as well as healthy volunteers. This study utilizes a CLDN18.2-specific PET imaging probe (e.g., \[\^68Ga\]Ga-labeled humanized antibody fragment) to evaluate the feasibility, accuracy, and clinical value of non-invasive, in vivo CLDN18.2 visualization. For patients with malignant tumors, the study will assess the diagnostic performance of CLDN18.2-targeted PET in identifying tumor lesions, compare the imaging results with gold-standard histopathology, determine the location, extent, and metabolic features of CLDN18.2-positive lesions, and evaluate tumor burden and treatment stratification value compared with \[\^18F\]FDG PET imaging. These results may assist in patient selection for CLDN18.2-targeted therapies (e.g., Zolbetuximab), guide clinical decision-making, and provide early prediction of therapeutic response. For healthy volunteers, pharmacokinetic profiling will be conducted to investigate the biodistribution, clearance, and safety of the radiotracer in vivo.