Castleman's disease of the kidney: Sonographic findings.

We report a case of rare Castleman's disease of the kidney that mimicked a renal neoplasm with emphasis on the imaging and histologic findings. A 47-year-old man presented with dyspeptic symptoms. Ultrasound revealed a vascular, heterogeneous mass in the left kidney. Multiphasic CT scan confirmed an enhancing lesion with enlarged left para-aortic lymph nodes suspicious for nodal metastases. The provisional diagnosis was renal cell carcinoma. Percutaneous biopsy yielded a diagnosis of Castleman's disease of the hyaline-vascular type. Despite advancement in imaging modalities, differentiation of hyaline-vascular variant of Castleman's disease from hypervascular renal neoplasm remains difficult and the final diagnosis requires histopathological confirmation.