Prognostic factors and treatment of patients with advanced synovial sarcoma: A single-center experience

BACKGROUND: Synovial sarcoma (SS) is a malignant mesenchymal tumor, which comprises 5%-10% of all the sarcomas. There is insufficient information on prognostic factors and salvage treatments of advanced SS. In this study, we aimed to further clarify the clinicopathological features, prognostic factors, and treatment modalities in advanced SS. MATERIALS AND METHODS: A total of 45 SS patients followed up between 2001 and 2015 at our cancer institute, Department of Medical Oncology, were retrospectively evaluated. Eleven patients were initially metastatic, and remaining patients developed metastasis or became inoperable due to locally advanced disease. Overall survival was evaluated by Kaplan-Meier analysis. RESULTS: The median age of patients was 37 (17-70) years and 60% (n = 26) of them were female. SS was most commonly localized in the lower extremity and abdomen-pelvis (29% and 29%, respectively). Median follow-up time was 33 (6-175) months. Patients were treated with a median of two (1-5) line chemotherapies at metastatic stage. Ifosfamide plus adriamycin (IMA) (49%, n = 22) and cisplatin-etoposide (13%, n = 6) were the most often used chemotherapy regimen as first line in metastatic stage. Partial response was obtained in 32% of the patients treated with IMA chemotherapy. Furthermore, median progression-free survival was 6 (1-123) months. Median survival of metastatic stage at diagnosis or in follow-up was 21 months (14-27) and 21 (12-29) months (P = 0.53), respectively. Most metastatic locations were lung (75%) and bone. Factors influencing survival at metastatic stage were evaluated; statistically significant longer survival was observed in patients with lung metastasis, primary tumor size smaller than 10 cm, patients who underwent surgery for the metastasis, and development-to-metastasis period longer than 12 months. CONCLUSION: Median survival of patients in metastatic stage SS was 21 months. Lung was the most common metastatic site.