Primary synovial sarcoma of the kidney: A case report.

Synovial sarcoma (SS) is a soft-tissue tumor with a unique t(X;18)(p11.2;q11.2) chromosomal translocation that can be identified by polymerase chain reaction in tissue homogenates. Generally, the tumor occurs in the proximity of the joints. The current study presents the case of a 54-year-old female with primary SS (PSS) of the right kidney; this is an extremely rare tumor accounting for <2% of malignant renal carcinomas. The patient presented with an interrupted right flank pain of 20 years duration, with a precipitating factor of a hematuria of 8 days. Abdominal computerized tomography (CT) scan revealed a heterogeneous, unclear-marginated soft tissue arising in the upper pole of the right kidney with solid, necrotic components and heterogeneous enhancement. Renal cell carcinoma was diagnosed pre-operatively. A right nephrectomy was performed, and the patient is currently free of metastasis 12 months after the surgery. The current treatment for renal SS includes surgical resection and ifosfamide-based chemotherapy. To the best of our knowledge, <50 cases have been reported in the English literature. Urologists should be aware of the possibility of malignancy in cystic renal masses and consider a diagnosis of SS. Along with the case report, the current study presents a literature review on the diagnosis and treatment of PSS.