Abstract
We report a case of retroperitoneal fibrosis mimicking pancreatic metastasis of renal cell carcinoma. A 73-year-old female had a radical nephrectomy for a renal mass. On pathology, renal cell carcinoma, pT3a N0 stage III was diagnosed. Within 8 months of surgery, a control CT scan demonstrated a left retroperitoneal mass, contiguous with the pancreatic tail and splenic hilum, suggesting local relapse. The patient had a resection of the mass with a splenectomy, partial colectomy, and partial pancreatectomy en bloc. Microscopic evaluation revealed a dense collagenic tissue with a prominent inflammatory infiltrate. Immunohistochemical studies showed positive nuclear staining for β-catenin. All these findings help make a diagnosis of retroperitoneal fibrosis. Retroperitoneal fibrosis can simulate or be associated with malignancies.
