A patient with recurrent abdominal pain was admitted to our hospital. Computed tomography showed a soft dense mass surrounding the abdominal aorta at the infrarenal level, which was compatible with retroperitoneal fibrosis. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography showed abnormal uptake of 18F-FDG into these lesions. Two months after the initiation of corticosteroid therapy, the abnormal uptake of 18F-FDG had ceased along with a reduction in the fibrous mass surrounding the abdominal aorta.
- Positron emission tomography