The difference of IGF-1 level between high-grade (497.7 ± 21.73) vs low-grade (406.7 ± 28.47) (P=0.003), metastatic (542.6 ± 34.86) vs non-metastatic (435.1 ± 85.83) (P=0.004) and recurrent (565.9 ± 40.89) vs non-recurrent (437.4 ± 17.14) (P=0.004) Ewing sarcoma tumors was statistically significant (Figure 4E). The gene discussed is IGF1; the disease is Ewing sarcoma.