Symptoms:

Early symptoms:

• Dull pain in the abdomen that increases with time
• Swelling of one leg
• Decreased circulation in the legs leading to pain and discoloration
• Severe abdominal pain with hemorrhage due to ischemic bowel

Later symptoms:

• Decreased urine output
• Total lack of urine (anuria)
• Nausea, vomiting, changes in thinking caused by kidney failure and the resulting build-up of toxic chemicals in the blood.

Signs and tests:

• Serum BUN and creatinine showing elevated levels
• Kidney ultrasound showing hydronephrosis (distention of the kidney pelvis because of fluid accumulation) and a mass
• Excretory urography showing compression and deviation of the ureters
• Abdominal CT scan (the best test to reveal the retroperitoneal mass)
• MRI (compares well to the CT scan)
• Biopsy showing either retroperitoneal fibrosis or a cancerous tumor