An analysis of clinical characteristics and patient outcomes in primary mediastinal sarcomas

Published data concerning primary mediastinal sarcomas are limited to small-sized retrospective series.  This study reviewed the clinical outcomes of these cases from the SEER (surveillance, epidemiology and end results) database.

Primary mediastinal sarcomas (1988 - 2013) were assembled from the SEER database. The incidence and 10-year cancer-specific survival rates were compared to other primary mediastinal malignancies (thymic carcinoma, germ cell tumors, neurogenic tumors, Hodgkin / non Hodgkin lymphomas) as well as to non mediastinal sarcomas.

A total of 204 patients were recruited into this cohort. Multivariate analysis showed better overall survival for patients with younger age at diagnosis, low grade [hazard ratio 0.427 (95% CI: 0.224-0.814; P= 0.010)], posterior mediastinum location [hazard ratio 0.458 (95% CI: 0.268-0.781; P= 0.004)], node negative disease [hazard ratio 0.463 (95% CI: 0.232-0.923; P= 0.029)] and surgical treatment [hazard ratio 0.488 (95% CI: 0.336-0.709; P <0.0001)]. Compared to other mediastinal malignancies, primary mediastinal sarcomas have the worst 10-year overall survival. Similarly compared to non mediastinal sarcomas, primary mediastinal sarcomas have worse 10-year overall survival (23% versus 55%).

Primary mediastinal sarcoma is a rare entity with worse prognosis compared to non-mediastinal counterparts. Surgical resection plays a particularly important role in the management.