Vascular endothelial growth factor expression in osteosarcoma. Vascular endothelial growth factor expression by osteosarcomas at biopsy has been shown to have a negative influence on survival. Whether it continues to be expressed and influence outcome in tumors after neoadjuvant chemotherapy has not been determined. To determine if a high-degree of vascular endothelial growth factor expression by the surviving osteosarcoma cells in the resected tumor has a negative influence on prognosis, we retrospectively reviewed 52 patients with Stage IIB osteosarcoma around the knee, 48 of whom received neoadjuvant chemotherapy. Vascular endothelial growth factor expression by the surviving tumor cells in the surgically resected specimens was determined by immunohistochemical staining. Followup was for a minimum of 92 months. The presence of vascular endothelial growth factor expression in greater than 25% of tumor cells was independently associated with a reduced overall and disease-free survival rate.Prognostic study, Level II (retrospective study). See the Guidelines for Authors for a complete description of levels of evidence.