Abstract
Primary synovial sarcoma of the mediastinum is an extremely rare and aggressive neoplasm that, in most cases, develops in young adults and is characterized by symptoms such as shortness of breath, cough, and chest pain. Diagnosis is challenging due to the atypical location of the tumor. The differential diagnosis is broad, and immunohistochemistry combined with molecular cytogenetic analysis represents the key diagnostic approach. Surgery remains the treatment of choice for these patients, with the addition of adjuvant chemotherapy and radiation therapy. We report a rare case of primary synovial sarcoma of the posterior mediastinum in a 33-year-old woman presenting with airway and vascular compression. The diagnosis was confirmed by fluorescence in situ hybridization, demonstrating SS18 translocation. Complete surgical excision with aortic wall reconstruction under cardiopulmonary bypass was performed. The patient remains disease-free following adjuvant therapy.