Serial 68Ga-FAPI PET/CT After Treatment of Immunoglobulin G4-Related Pancreatitis and Retroperitoneal Fibrosis.

ABSTRACT: Immunoglobulin G4 (IgG4)-related disease is a fibroinflammatory condition involving diverse organs. We report a case of IgG4-related pancreatitis and retroperitoneal fibrosis with serial 68Ga-FAPI PET/CT scans after treatment. A 64-year-old man presented with left flank and epigastric pain. Laboratory, abdominal CT, and 68Ga-FAPI PET/CT findings were suggestive of IgG4-related pancreatitis and retroperitoneal fibrosis. Histology of the pancreas confirmed IgG4-related pancreatitis. The follow-up PET/CT scans after treatment with steroid therapy showed regression of 68Ga-FAPI uptake in the pancreas and periureteral soft tissue. The changes on 68Ga-FAPI PET/CT scans were much more prominent compared with the CT scans.

68 Ga-FAPI PET/CT Imaging of the Pancreas in a Patient With Fulminant Type 1 Diabetes.

ABSTRACT: Fulminant type 1 diabetes is a recently recognized diabetes subtype characterized by extremely rapid destruction of the pancreatic beta cells, leading to an absolute deficiency in insulin secretion. Fulminant type 1 diabetes is clinically characterized by the drastic onset of hyperglycemia and ketoacidosis within a few days, as well as near-normal glycated hemoglobin (HbA 1c ) levels despite remarkable hyperglycemia at initial presentation. A 41-year-old woman diagnosed with fulminant type 1 diabetes underwent 68 Ga-FAPI PET/CT, which showed intense FAPI uptake throughout the pancreas, especially in the pancreatic tail. Contrast-enhanced abdominal CT failed to reveal any pancreatic abnormalities. This case indicated that 68 Ga-FAPI PET/CT might be useful for evaluating patients with fulminant type 1 diabetes.