Abstract
Pulmonary synovial sarcoma is a rare but aggressive disease. The present study describes the case of a 68-year-old female with pulmonary synovial sarcoma. The patient was mistakenly treated for small cell lung cancer due to false-positive staining for synaptophysin and cluster of differentiation 56. Despite severe myelotoxicity, platinum-containing chemotherapies (cisplatin plus irinotecan and carboplatin plus etoposide) were not effective. As a third-line therapy, the patient received amrubicin (AMR) monotherapy. A partial response was achieved, and the patient was able to undertake ordinary daily life at home for 13 months from the initiation of AMR chemotherapy. Due to the atypical clinical condition and unusual response to chemotherapy in this patient, the pathological examination was repeated. The SS18 split-signal was detected in fluorescence in situ hybridization analysis. From these results, the tumor was diagnosed as a monophasic synovial sarcoma. To the best of our knowledge, this is the first case of a patient with pulmonary synovial sarcoma who underwent successful treatment with AMR. The present case could demonstrate a specific chemosensitivity of such a rare tumor.