68 Ga-FAPI PET/CT Depicted Non-FDG-Avid Malignant Peritoneal Mesothelioma.

Malignant peritoneal mesothelioma (MPM) is a rare and aggressive malignancy of mesothelial cells in the peritoneum. Herein, we describe the 68 Ga-FAPI and 18 F-FDG PET/CT findings of MPM in a 41-year-old man. In the present case, the primary and metastatic tumors showed intense 68 Ga-FAPI accumulation but no significantly increased 18 F-FDG uptake. This case demonstrates that 68 Ga-FAPI PET/CT might be used as a helpful tool for evaluating MPM staging.