The liver is normal in size and density. No focal hepatic lesion. The gallbladder is unremarkable. No dilatation of the biliary tree. There is a thin rim of hypodensity around the pancreas.
Extensive retroperitoneal soft tissue density surrounding both adrenals, kidneys, ureters, lower abdominal vasculature and pelvic vasculature, bladder and prostate. Left DJ stent in situ.
Generalised stranding of the mesentery. Mild stranding associated with the ascending colon.
Soft tissue encasing the majority of the retroperitoneal structures consistent with the known diagnosis of Erdheim Chester disease.