Skeletal muscle metastasis from a conventional renal cell carcinoma, two years after nephrectomy: a case report

In this paper, we describe a case of skeletal muscle metastasis from a conventional (clear cell) renal cell carcinoma, two years after nephrectomy. Our first clinical tentative diagnosis was soft tissue tumour, showing the mimicking capacity of renal cell carcinoma. A review of literature shows that skeletal muscle metastases from renal cell carcinoma are extremely rare: only 16 cases have been described. In 5/16, the muscle mass was the initial manifestation of the renal tumour. In the other 11/16, the muscle masses were metachronous (10 months-16 years). We conclude that, when confronted with a patient with a muscle mass and a history of renal cell carcinoma, one should always keep in mind the possibility of a (late) renal cell carcinoma metastasis.