A prognostic evaluation of vascular endothelial growth factor in children and young adults with osteosarcoma. The potential role of VEGF in osteosarcoma has been evaluated in several studies. The majority of them included heterogeneous and limited series of patients, giving conflicting results. The aim of presented study is to evaluate the prognostic role of VEGF-A in biopsy samples of clinically homogeneous group of osteosarcoma patients with at least 5 years of follow up.VEGF-A was assessed immunohistochemically in the pre-treatment biopsy samples of 91 patients (mean age 14 years; range, 4-23 years) with primary, high-grade, non-metastatic osteosarcoma localized in extremities. The survival of each patient was assessed after at least 5-year follow-up period.VEGF-A over 50% of positive tumor cells was observed in 39% of cases and was linked to patients age below 14-year old (P = 0.025) and tumor size more than 8 cm (P = 0.054). VEGF-A was associated with a significantly decreased both overall survival (P = 0.006) and progression-free survival (P = 0.011). In the Cox proportional hazard model it was confirmed that VEGF-A expression in the biopsy samples was an independent prognostic factor of unfavorable survival in osteosarcoma (HR 2.51; 95% CI: 1.12-5.66).The expression of VEGF-A in the biopsy sample is the potential marker for predicting the course and outcome of osteosarcoma.Copyright © 2011 Wiley-Liss, Inc.