Primary monophasic synovial sarcoma presenting as a pulmonary mass: a case report

INTRODUCTION: Primary pulmonary synovial sarcoma is an extremely rare tumor with only few case reports in the literature. CASE PRESENTATION: A healthy 67-year-old woman was admitted for investigation of a pulmonary mass found on a routine X-ray. She had a history of breast cancer diagnosed and treated 13 years previously with left mastectomy followed by adjuvant endocrine therapy. No progression of the disease was reported. Thoracic computer tomography disclosed a soft-tissue mass in the lower lobe of the left lung arising in the vicinity of the pleura. No abnormal lymph nodes were noted. Further work-up for metastases was negative. Subsequently, the lower lobe of the left lung was removed and the diagnosis was a monophasic synovial sarcoma. CONCLUSION: The diagnosis of monophasic primary pulmonary synovial sarcoma requires clinical, imaging and immunohistochemical investigation to exclude alternative primary sources. The treatment of choice is excision (lobectomy or pneumonectomy), which in most of cases is helpful for diagnosis. The prognosis is usually poor.