RADIOTHERAPY IN EWINGS-SARCOMA - CONCLUSI ONS FROM THE CESS-86 PROTOCOL

In CESS 86, radiotherapy and surgery as local treatment modalities yie lded the same survival rates. Irradiated patients developed more local recurrences as compared to surgically treated patients (14% versus 4% ), but less systemic metastases (16% versus 28%). The local recurrence rate after definitive radiotherapy dropped from 50% in CESS 81 to 14% in CESS 86. This was probably caused by an earlier start of radiother apy (in week 10 in CESS 86 as compared to week 19 in CESS 81) and the high quality of radiation therapy in CESS 86 due to central treatment planning (only 2% protocol violations). Patients with local recurrence s showed no differences in the distribution of major prognostic parame ters (tumor volume, response to chemotherapy) as compared to patients with local control of disease. As a consequence of these results the c oncept of early irradiation with subsequent ,,consolidant'' surgery fo r high-risk patients has been established.