Ewing Sarcoma Prognostic Score (Esps) At Diagnosis, Based On Fever And Metastatic Status.

9539 Background: Our purpose was to identify prognostic factors in Ewing's sarcoma (ES) at diagnosis that could allow better treatment stratification. Methods: Between 1988 and 1999, 486 patients (pts) with localized (n=364) or metastatic (n=122) ES were enrolled in two French protocols EW88 and EW93. Characteristics at diagnosis of the patient (age, gender, fever) and of the tumor (initial tumor volume (ITV), primary location, presence and type of metastasis [METS]) were prospectively collected and their influence on disease-free survival (DFS) was assessed. Results: With a 8.5 years median FU, the number of events is 242 (49.8%). By univariate analysis, the following features were found to be associated with a poor prognosis: age <7 or ≥15 years (p=0.001), axial and proximal (femur, humerus) location (p=0.0001), presence of fever (p<.0001), ITV > 200 ml (p<.0001), metastases (p<.0001). In metastatic patients, prognosis for lung only mets was better than for other mets (p=0.006). In the multivariable analysis, the presence of fever and the metastatic status remained prognostic and serve to build a prognostic score summing these two variables assigning a two score point for “other mets” (cf table). This resulted in four groups with significant different 5-year DFS: 60% for ESPS=0 (localized tumour without fever), 47% for ESPS=1 (localized tumor with fever or isolated lung mets without fever, HR=1.47), 29% for ESPS=2 (isolated pulmonary metastasis with fever or other metastasis without fever, HR=1.75) and 10% for ESPS=3 (febrile patients with other mets, HR=5.12). Conclusions: The Ewing Sarcoma Prognostic Score identifies, at diagnosis, very different prognostic groups which might benefit from different treatment strategies. The prognostic value of this ESPS warrants confirmation in a large independent population. Fever Isolated lung mets Other mets No. (%) of patients 5-year DFS Prognostic score ESPS 5-year DFS byscore Hazard ratio [95%CI] P value 0 0 0 302 (65) 60% 0 60% 1 1 0 0 49 (10) 46% 1 47% 1.47 [1.06-2.06] 0.023 0 1 0 43 (9) 47% 1 1 0 11 (2) 27% 2 29% 1.75 [1.16-2.64] 0.007 0 0 2 40 (9) 29% 1 0 2 22 (5) 10% 3 10% 5.12 [3.00-8.73] <0.001