ABSTRACT
Objective To discuss the presentations, pathologic features, diagnosis and treatment of primary synovial sarcoma of the kidney. Methods One case of primary synovial sarcoma of the kidney was reported and the relevant literature was reviewed. A 55-year-old man was admitted with complaint of right abdomen and flank pain for 5 h. Computerized tomography revealed a 12.5 cm × 11.0 cm × 9. 0 cm mass located at the middle and lower pole of the right kidney. The patient was taken radical nephrectomy. Results The diagnosis of primary synovial sarcoma of the kidney in the patient was confirmed by postoperative pathology. Under microscope, tumor was typically mitotically active, monomorphic spindle cells growing in intersecting fascicles or in solid sheets with epithelial differentiation. In some areas a haemangiopericytoma-like pattern was found. Immunohistochemical staining showed that the tumor cells were positive for the markers Vimentin, CD99 and Bcl-2, but CK was negative. The patient died of local recurrence and multi-metastasis at 8 months after surgery. Conclusions Primary synovial sarcoma of the kidney is extremely rare with a high grade of malignancy,and its prognosis is poor. The diagnosis depends on pathological features, Immunohistochemical studies and RT-PCR detection. Radical resection combined with chemicaltherapy is considered to be the most reliable treatment so far.