%0 Journal Article %T Primary Synovial Sarcomas of the Mediastinum: A Systematic Review and Pooled Analysis of the Published Literature %A Samer Salah %A Ahmed Salem %J ISRN Oncology %D 2014 %R 10.1155/2014/412527 %X Background. The aim of this systematic review is to attempt to provide a descriptive analysis for cases of synovial sarcoma (SS) arising in the mediastinum and to analyze prognostic factors. Methods. We performed PubMed database search in July 2013. Twenty-two studies, which included 40 patients, form the basis of this review. Demographic and disease-related factors were analyzed for possible influence on survival. Findings were compared with extremity SS studies reported in literature. Results. Sixteen cases (40%) presented with locally advanced unresectable disease, 2 (5%) with metastatic disease, and 22 (55%) with localized resectable disease. Median tumor size was 11£¿cm (range: 5¨C20£¿cm). Thirty patients were assessable for survival and had a 5-year OS of 36%. Completeness of resection was the only factor associated with significant improvement in OS (5-year survival of 63% and 0% in favor of complete resection, ). Conclusion. Mediastinal SS is associated with poor prognosis as more cases are diagnosed at an advanced stage and with larger tumor size compared to extremity SS. Complete surgical resection is the only identified factor associated with better prognosis and may result in survival outcomes that are comparable with those for localized SS of the extremity. 1. Introduction The mediastinum is a host for a variety of primary and secondary malignancies. Metastatic carcinomas, lymphomas, and thymomas are the most commonly encountered tumors. Synovial sarcoma (SS), though very rarely encountered, could also arise in this location [1¨C8]. Around 80% of synovial sarcomas arise in the extremities [9, 10]. In that context, prognostic factors for survival and recurrence are well characterized. Tumor size of ¡Ý5£¿cm [11¨C17] and completeness of resection [16, 18, 19] are the most consistent prognostic factors among previous reports. Other factors, though less consistently identified, include bone or neurovascular invasion [14, 20, 21], high histologic grade [20, 21], and the histologic subtype [15, 19]. It is not clear if these prognostic factors retain their significance in cases of mediastinal SS. Furthermore, the distinctive features that are unique to the mediastinal site of occurrence of those tumors as opposed to other sites, including the tendency to present with larger size, and their site within the mediastinum (anterior, middles, or posterior mediastinum) as well as the presence of pericardial invasion and effusions, make any application of the previously identified prognostic factors irrelevant. In the current paper, we attempt to provide a %U http://www.hindawi.com/journals/isrn.oncology/2014/412527/