68Ga-FAPI has been developed as a tumor-targeting agent as fibroblast activation protein is
overexpressed in cancer-associated fibroblasts and some inflammation,such as IgG4-related
disease.And it might be more sensitive than FDG in detecting a certain type of inflammations
according to our preliminary research.Thus this prospective study is going to investigate
whether 68Ga-FAPI PET/CT may be superior for diagnosis, therapy response assessment and
follow-up of IgG4-related disease.