Solitary pulmonary nodule: pleuropulmonary synovial sarcoma

Pleuropulmonary synovial sarcoma (PPSS) is an extremely rare primary malignancy of the lung. We present a case of a middle-aged female with PPSS that was initially discovered as an incidental indeterminate nodule on chest radiograph. Following evaluation with computed tomography (CT), the patient went on to positron-emission tomography (PET)/CT for work-up of the solitary pulmonary nodule, which demonstrated mild FDG-avidity and no other evidence of FDG-avid disease. The patient then underwent thoracotomy and right upper lobectomy for definitive treatment. Only after evaluation of the gross pathology, histology, immunohistochemistry and cytogenetics was the diagnosis of synovial sarcoma made. Importantly, the preceding PET/CT, in addition to physical exam of the upper and lower extremities, helped exclude the more common extra-thoracic soft-tissue variety of synovial sarcoma, which frequently metastasizes to lung, carrying a worse prognosis. Discussion of synovial sarcoma and PPSS follows.