[Osteosarcoma and Ewing's sarcoma--The most frequent malignant bone tumors in children--therapy and outcome]

Osteosarcoma and Ewing's sarcoma are the most frequent malignant bone tumors in children and young adults with relatively poor overall survival rates.

Between January 1980 and December 1994, 175 children with osteosarcoma and 64 children with Ewing's sarcoma were treated at the author's institution. 22 children had synchronous metastases, 19 patients had a pathologic fracture. Both groups were treated systemically with chemotherapy regimens (COSS and CESS). Local therapy was amputation or tumor resection and endoprosthetic replacement or biological reconstruction with wide or radical resection margins. In case of Ewing's sarcoma in 35 patients postoperative radiation therapy was done.

Five-year overall survival rate for osteosarcoma and Ewing's sarcoma patients is about 63 %, ten-year survival rate for osteosarcoma patients is 60.2 %, for Ewing's sarcoma patients 54.5 %. Prognostic factors significantly influencing overall survival rates are tumor response to chemotherapy (p values = 0.0056 and 0.013, respectively), surgical treatment with adequate resection margins (p value = 0.0001 for osteosarcoma patients) and development of postoperative metastases (p value = 0.0001 for both groups).

For both groups of malignant bone tumors systemic chemotherapy as well as adequate surgical therapy are necessary to reduce the rates of local recurrences and to achieve better survival rates.