Retroperitoneal fibrosis with pancreatic involvement : radiological appearance

Background: Retroperitoneal fibrosis or Ormond's disease is an uncommon process characterized by fibrous tissue proliferation in the retroperitoneum, usually involving the aorta, inferior vena cava and iliac vessels. Obstructive hydronephrosis is often observed due to ureteral entrapment. This report presents a case of the peripancreatic location of the disease. The role of CT and MRI in establishing diagnosis of retroperitoneal fibrosis in an atypical site is discussed. Case Report: A 52-year-old woman with Hashimoto's thyroiditis was admitted to hospital because of pain suggesting renal colic. The patient was subjected to ultrasound, CT, and MRI which did not confirm urolithiasis but revealed pancreatic infiltration. Partial pancreatectomy, left-sided adrenalectomy and splenectomy were performed. Retroperitoneal fibrosis was diagnosed in the histopathological examination. A few weeks after surgery, a complication such as pancreatitis developed. Repeat CT confirmed it and showed right hydronephrosis secondary to ureteral involvement by a mass adjacent to the common iliac artery (defined as a typical manifestation of retroperitoneal fibrosis). Nephrostomy and conservative treatment improved the clinical state of the patient. No progression of the process was observed in the follow-up examinations. Conclusions: Atypical retroperitoneal fibrosis remains a diagnostic challenge. Imaging techniques CT and MRI are useful tools for evaluating the extent of Ormond's disease. An unusual distribution of the process (e.g. peripancreatic location reported in this study) requires histopathological assessment to establish the final diagnosis.