Prognostic implication of SYT-SSX fusion type and clinicopathological parameters for tumor-related death, recurrence, and metastasis in synovial sarcoma.

The present study aimed to describe the distribution and features of the SYT-SSX fusion gene in Chinese patients with synovial sarcoma (SS), and to analyze the prognostic value of SYT-SSX fusion type and clinicopathological parameters for tumor-related death, recurrence, and metastasis in SS. SYT-SSX1 and SYT-SSX2 fusion transcripts were tested by reverse transcription-polymerase chain reaction in 141 formalin-fixed, paraffin-embedded SS. The prognostic implication of SYT-SSX fusion type and clinicopathological parameters were analyzed by univariate and multivariate survival analyses. SYT-SSX1 and SYT-SSX2 were detected in 50 (34.5%) and 91 (64.5%) tumors, respectively. SYT-SSX1 (risk ratio [RR] = 2.032, P = 0.004), larger tumor size (RR = 1.859, P = 0.008), and aggressive Fédération Nationale des Centers de Lutte Contre le Cancer grade (RR = 2.094, P = 0.001) were adverse predictors for disease-specific survival. However, SYT-SSX fusion type was not associated with local recurrence-free survival (P = 0.216). Patients with larger tumors (RR = 2.071, P = 0.005) and those who received marginal excision (RR = 2.556, P = 0.005) had poor local recurrence-free survival. Besides, SYT-SSX1 (RR = 1.859, P = 0.037), older age (RR = 1.799, P = 0.040), and aggressive International Union Against Cancer stage (RR = 3.690, P < 0.001) proved to be adverse prognostic factors for metastasis-free survival. In conclusion, compared to SYT-SSX1, SYT-SSX2 was more frequent in Chinese patients with SS. Moreover, SYT-SSX1 was an adverse predictor for disease-specific survival and metastasis-free survival, but had no relation to local recurrence-free survival. In addition, histological grade and tumor size were also important prognostic factors for SS.