Synovial sarcoma: Do children do better?

Objectives: Synovial sarcoma, a distinct subtype of soft tissue sarcomas (STS), is typically found in young patients. Long history of symptoms and heterogeneous clinical presentation sometimes delays diagnosis. Children have been reported to have a better prognosis than adults in some series. The main emphasis of this study was to determine differences between children and adults and to investigate prognostic factors regarding cancer specific survival (CSS).

Methods: 248 patients treated between 1982 and 2014 at one department were included. Mean age was 37.0 years, including 43 patients <16 years. Demographic, pathology- and treatment-related information was ascertained. Median follow-up was 5.2 years.

Results: Median duration of symptoms was 11.5 months in children and 12 months in adults (p = 0.238). Patients with a prior unplanned excision had a significantly longer duration of symptoms (p = 0.001). No difference was present between children and adults regarding tumour size, site, grade and superficial/deep location. Treatment was with surgical excision and (usually) adjuvant radiotherapy but five patients received preoperative radiotherapy and 43 patients chemotherapy. In patients treated with curative intent, five-year CSS rates were 75.5% for adults and 89.0% for children, with 10-year CSS rates of 56.1% and 82.2% (p = 0.026). In multivariate analysis, large tumour size (p < 0.005) and patient age (p = 0.024) were associated with worse CSS, irrespective of tumour location and site.

Conclusion: Clinical presentation of synovial sarcoma is similar in children and adults, with no significant difference in tumour size, site, grade or location. Small tumour size and young patient age are independent positive prognostic factors influencing CSS.