[Case of renal cell carcinoma metastasized to iliopsoas muscle].

Skeletal muscle metastasis is a rare event in renal cell carcinoma (RCC). Only thirty-two cases have been reported until now. A 69-year-old female had a nephrectomy for right RCC (clear cell carcinoma, grade 2, pT1) in 1994. She has been followed up every three months after nephrectomy. After twelve years from nephrectomy, computed tomography (CT) showed a 3 cm mass in the right iliopsoas muscle. CT guided needle biopsy revealed tumor cells suspicious of renal cell carcinoma metastasis. The tumor was surgically removed and histologically diagnosed as renal cell carcinoma metastasized to the iliopsoas muscle.