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Published on: December 9, 2016
Extra-osseous Ewing sarcoma
Hendrik van den Berg1, Richard C Heinen, Heleen J van der Pal
1Department of Paediatric Oncology, Emma Children Hospital AMC, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. h.vandenberg@amc.uva.nl
Background:
Clinical data and data on outcome of extra-osseous Ewing tumors are scarce.
Procedure:
After a search for Ewing tumors in the database of a single institution over a period of 20 years, 16 out of 192 cases were found to have extra-osseous primary tumors.
Results:
Ages at initial diagnosis ranged from 2.5 to 17 years. Follow-up period ranged from 4 months to 24.8 years (mean 8.4 years). Eleven patients were treated according to protocols for Ewing tumors, while in 4 cases soft tissue protocols were used. In a single patient only surgery was done. Two patients had progressive disease despite chemotherapy; a third patient had only tumor response on the initial 2 chemotherapy courses. All 3 patients with initially metastatic disease died. One patient developed a second malignancy. Overall survival at 5 years was 75%. Event-free survival (EFS) at 5 years was 68%; for nonmetastatic patients 5-year EFS was 83%.
Conclusion:
The authors conclude that nonmetastasized extra-osseous Ewing tumors have a prognosis at least similar to that of osseous Ewing tumors.
