IL1B and Ewing sarcoma: Although 23.1% of patients with Ewing sarcoma who had low IL-1β had metastatic disease compared with 42.9% with high IL-1β (p = NS), in the osteosarcoma cohort, only 4% of patients with low IL-1β had metastatic disease compared to 37.5% in the high IL-1β group (Figure 6B; p = 0.036).