False statement concerning the diagnosis and management of retroperitoneal fibrosis include ?

Ninety percent of patients with retroperitoneal fibrosis present with dull, non-colicky pain in the back, flank, or abdomen. Diagnosis is most commonly suggested by intravenous pyelography. The combination of medial detion of the ureter, hydroureteronephrosis, and extrinsic ureteral compression are highly suggestive of retroperitoneal fibrosis. CT scanning or MRI can both define the level of ureteral involvement and depict the mass appearance of the fibrotic process. Exploratory laparotomy with multiple deep biopsies of the retroperitoneal process is an essential pa of diagnosis, since foci of carcinoma may be sparse within the predominately sclerotic reaction. Prognosis for patients with non malignant retroperitoneal fibrosis is good. Survivals of 86-100% for several years have been repoed.