Retroperitoneal fibrosis as host response to papillary renal cell carcinoma.

A case of papillary renal cell carcinoma associated with retroperitoneal fibrosis is described. This type of fibrosis has not been previously reported to be associated with renal cell carcinoma. The case is of additional interest in that it implicates an immune phenomenon in the pathogenesis of the fibrosis, involving both putative tumor antigens and antigens associated with tumor growth but unrelated to tumor cells.