Synovial sarcoma is a soft tissue sarcoma, of uncertain histological origin, usually located near large joints and concerning mainly young adults. Intracranial presentation in the form of metastasis from a primitive body sarcoma has been rarely reported. However, intracranial primitive synovial sarcoma (IPSS) is extremely rare and only a few cases have been reported in the literature.

We present the case of a 48-year-old man, with no particular medical history, that was referred to our hospital for severe headache with a normal neurological exam and a CT cerebral scan showing a left frontal lobe hematoma. The initial cerebral CT scan didn’t show any vascular malformation and the body CT scan was negative for a primitive lesion. A close follow-up with a cerebral MRI three months later, demonstrated a T1 enhanced lesion with an important volume progression. The patient underwent a complete surgical removal of this lesion and the first pathology diagnosis was compatible with a meningioma. After further proofreading by an expert and molecular analysis, the diagnosis of monophasic synovial sarcoma was confirmed. Nine months after the first surgery, the follow-up MRI showed the progressive recurrence of the lesion and in this context the patient underwent a second surgery with total resection of the tumor and frontal thin margin excision. Afterwards, the patient was treated with adjuvant radiotherapy, with a good clinical evolution, and till now the follow-up shows no recurrence.

IPSS is an extremely rare sarcoma, with challenging diagnosis and difficult management. Specific molecular analysis is necessary. Complete resection followed by radiotherapy seem to be the most appropriate therapeutic approach. However, the prognosis is still poor. Our case is even rarer because of the initial presentation as a cerebral hematoma.