Biphasic Synovial Sarcoma: A Rare Oncological Entity

Synovial sarcoma is a rare and aggressive soft-tissue malignancy that arises near joints, tendons and bursae. It accounts for about 5% of soft-tissue sarcomas, and amongst its histological variants, the biphasic subtype comprises roughly 30% of cases. This case report describes the case of a 55-year-old female presenting with biphasic synovial sarcoma in the left leg, characterised by a progressively enlarging, painless mass. Diagnostic imaging, including ultrasonography and magnetic resonance imaging, identified the lesion’s size, extent and characteristics. Histopathological evaluation confirmed the diagnosis, supported by immunohistochemical markers such as TLE1 positivity and a high Ki-67 index. Treatment involved wide local excision followed by adjuvant radiotherapy, reflecting a multimodal approach tailored to the tumour’s high grade and large size. This case underscores the importance of integrating imaging, pathology and multidisciplinary management strategies in addressing rare, high-grade malignancies to optimise the patient outcomes.