PRIMARY OBJECTIVE:
I. To define the biodistribution of gallium Ga 68 FAPi-46 (68Ga-FAPi-46) in normal and cancer tissues of patients with various malignancies measured by standardized uptake values (SUV).
SECONDARY OBJECTIVE:
I. To assess the 68Ga-FAPI-46 biodistribution correlation with fludeoxyglucose F-18 (18F-FDG) biodistribution and to define the frequency of the following phenotypes (FAP+/ FDG+, FAP-/ FDG+, FAP+/ FDG-, FAP-/ FDG-).
OUTLINE:
Patients receive 68Ga-FAPi-46 intravenously (IV) and then, 20-90 minutes later, undergo PET/CT over 20-50 minutes. Patients may undergo optional 18F-FDG PET/CT on study.