Retroperitoneal castleman disease mimicking lymph node spread from clear renal cell carcinoma. A case report.

Renal Cell Carcinoma (RCC) corresponds to 3% of the neoplasms in the adults. Surgery is the main mode of treatment, which can be associated toretroperitoneal lymphadenectomy in the presence of clinically tumor positive lymph nodes. Castleman Disease (CD) is a rare lymphoproliferative disorder, with little-known etiopathogenesis. It rarely affects the retroperitoneum. Thorax, neck, and abdomen are more frequently affected. Therefore, CD can simulate lymphatic spread from RCC to the retroperitoneum, also leading to a possible misdiagnosis, or diagnosis concerning a paraneoplastic syndrome due to RCC.