['Stromal cell-derived factor-1 (SDF-1) expression has been reported to be a predictor of poor clinical symptoms in certain types of cancer. Vascular endothelial growth factor (VEGF) is a well-known factor that mediates the micro-angiogenesis of solid tumors, and SDF-1 mediated expression of VEGF may promote tumor growth and metastasis, resulting in poor clinical outcome. Therefore, we explored the expression levels of SDF-1 and VEGF in patients with osteosarcoma in order to determine the association between their expression levels and unfavorable outcomes.', 'A total of 54 patients with osteosarcoma were included in the current study. The protein expression levels of SDF-1 and VEGF were evaluated on immunohistochemical and immunofluorescence staining. The correlation between the expression levels of SDF-1 and VEGF and their association with clinical parameters were analyzed using the Pearson chi-square test and the Spearman-rho test. Univariate and multivariate Cox regression analyses were used to identify potential prognostic factors. The Kaplan-Meier method was employed to analyze overall survival.', 'Low SDF-1 and VEGF expression levels were detected in 20.4% (11 of 54) and 22.2% (12 of 54) of the patients with osteosarcoma, respectively; moderate expression was detected in 35.2% (19 of 54) and 37.0% (20 of 54) of the patients, respectively; and high expression was detected in 44.4% (24 of 54) and 40.7% (22 of 54) of the patients, respectively. Protein levels of both SDF-1 and VEGF were significantly associated with the histologic grade (p=0.004 and p=0.042 respectively), the presence of metastasis (p=0.009 and p=0.028 respectively), and Enneking staging (p<0.001 and p=0.003 respectively). The association between expression levels of SDF-1and VEGF had a significantly positive correlation (p<0.001and r=0.618). The expression levels of both SDF-1 and VEGF were significantly associated with shorter overall survival on univariate analysis; however, the association was significant for SDF-1 expression alone in the multivariate analysis (p=0.26, hazard ratio =2.640 [1.124-6.200]).'] Is sDF-1 Expression Associated with Poor Prognosis in Osteosarcoma?