Long-term Intense 18F-FDG Uptake by the Homeostatic Matrix-associated Inflammatory Response May Mimic Malignancy Recurrence.

A 70-year-old man underwent right upper lobectomy for lung adenocarcinoma. During the operation, hemostatic matrix (as known Floseal®) was used to prevent pulmonary laceration-associated bleeding. When 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography was performed for staging after surgery, intense 18F-FDG uptake was observed in the cicatricial fibrotic tissue in the operation area, and no significant change was observed in that area during the 4-year follow-up. Because it remained stable for several years without treatment, this finding was thought to be due to a foreign body reaction caused by the homeostatic material.