[Bilateral multilocular cystic renal cell carcinoma: a case report].

A case of bilateral synchronous multilocular cystic renal cell carcinoma is reported. A 52-year-old man was admitted to our hospital for further examination of right renal mass which was found incidentally by ultrasonography. After he was examined by intravenous pyelography (IVP), computerized tomographic (CT) scan, magnetic resonance imaging (MIR) and angiography, right nephrectomy was performed under the diagnosis of right renal cancer. Histological diagnosis was multilocular cystic renal cell carcinoma. CT scan revealed a small left renal cystic lesion at that time. Ten months later enhanced CT scan revealed irregular septum in the cystic lesion. Under the diagnosis of left renal cancer, we carried out simple enucleation. Histological diagnosis was multilocular cystic renal cell carcinoma as in the right kidney. The patient has been followed up carefully. This is the third case of bilateral multilocular cystic renal cell carcinoma, which is regarded as the first synchronous one, reported in Japan.