IGFBP3 and osteosarcoma: The patients with metastatic (5.51 ± 0.57) and recurrent (5.64 ± 0.66) osteosarcoma tumors showed higher level of IGFBP-3 in the serum compared to non-metastatic (3.91 ± 0.20) (P=0.001) and non-recurrent (3.93 ± 0.18) (P=0.001) osteosarcoma tumors (Figure 6D).