Abstract
Synovial sarcoma is a soft tissue neoplasm with clearly defined histologic, immunohistochemical and molecular features. These tumours usually arise in the extremities of young adults. Their occurrence in the kidney is extremely rare. A 25-year-old pregnant lady in her first trimester was incidentally found to have a left renal mass on perinatal ultrasonography. MRI showed a well encapsulated, heterointense mass replacing the left kidney. Following medical termination of her pregnancy, a radical nephrectomy was performed. Histopathology revealed a primary synovial cell sarcoma of the kidney. Postoperatively, she received ifosfamide based adjuvant chemotherapy. This report highlights the challenges involved in the diagnosis of this extremely rare neoplasm. A high index of clinical suspicion, complimented by the use of immunohistochemistry and cytogenetics during histopathological analysis aide in the diagnosis. Aggressive management with a combination of complete surgical extirpation and chemotherapy gives the best results.