Intense 68 Ga-Pentixafor Activity in Idiopathic Retroperitoneal Fibrosis.

A 52-year-old man was admitted to our hospital with lower abdominal and low back pain, and abdomen CT at an outside hospital presented a retroperitoneal mass with left urinary tract obstruction and hydronephrosis. In 68 Ga-pentixafor PET/CT, the retroperitoneal mass showed intense radioactivity. Subsequently, the patient underwent biopsy of the retroperitoneal mass. The pathological examination showed only fibrous tissue without tumor cells. The patient was finally diagnosed with idiopathic retroperitoneal fibrosis. Our case demonstrated that idiopathic retroperitoneal fibrosis had intense uptake of 68 Ga-pentixafor.