Synovial sarcomas represent an extremely rare subtype of an already rare group of malignancies, soft tissue
sarcomas. Among these, primary pulmonary synovial sarcomas comprise an even smaller number, though
they have become more frequently reported in the literature. This case report details a case of giant primary
pulmonary synovial sarcoma in a 44-year-old male patient who presented with left-sided chest pain and
shortness of breath and was found to have a large left-sided pleural effusion. No malignant cells were
demonstrated on cytology of pleural fluid after thoracentesis; however, CT-guided needle biopsy of pleural
nodules seen on imaging demonstrated pathologic features consistent with monophasic type synovial
sarcoma. He was treated with neoadjuvant chemotherapy with minimal response; thus, he was referred for
surgical management. A left extrapleural pneumonectomy with resection of the left hemi-diaphragm and
Gore-Tex prosthetic reconstruction was performed. Imaging at six-month follow-up demonstrated a new
nodule in the contralateral lung, suggestive of metastasis at that time and the patient later developed ascites
at nine months, consistent with further intra-abdominal metastasis. Perhaps early diagnosis and aggressive
multimodality therapy may have a place in the treatment of this aggressive disease.