Primary thoracic synovial sarcoma in a 45-year-old male: A case report and literature review.

Synovial sarcoma (SS), a rare soft tissue cancer, develops at various body sites, with a predominant occurrence in the limbs. This report presents a rare case of primary thoracic SS (PTSS) in a 45-year-old male patient, characterized by chronic cough and occasional shortness of breath. Imaging examination revealed a substantial tumor mass in the left thoracic cavity. Although preoperative biopsy misdiagnosed the tumor as a solitary fibrous tumor, postoperative molecular analysis revealed that the tumor was SS based on the characteristic t(X;18)(p11.2;q11.2) translocation. The precise origin of the tumor within the thoracic cavity remained unclear, and the involvement of the pleura, chest wall and mediastinum was considered. The patient underwent surgical resection of the tumor followed by adjuvant chemotherapy with doxorubicin and nedaplatin. Regrettably, the patient showed widespread metastatic progression 8 months post-surgery and died 18 months thereafter because of tumor dissemination and associated complications. This case highlights the diagnostic challenges of PTSS and underscores the need for increased clinical awareness of rare thoracic tumors.