Retroperitoneal fibrosis associated with renal cell carcinoma.

Retroperitoneal fibrosis is a rare condition. It is idiopathic or secondary to various diseases including autoimmune diseases and atherosclerosis [1]. Although its pathogenesis is unknown, it is now considered that immune responses may play an important role in this disease [1]. Retroperitoneal fibrosis is also seen in metastatic carcinomas from many organs as a desmoplastic reaction [1]. However, retroperitoneal fibrosis associated with primary urogenital carcinoma is very rare, and it has been reported in only several times [2-6]. It is very infrequently reported that renal cell carcinoma (RCC) may be associated with retroperitoneal fibrosis [3-6]. Here, the author reports a case of retroperitoneal fibrosis associated with RCC of clear cell type with focal spindle changes.