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Concentration of vascular endothelial growth factor (VEGF) in the serum of patients with malignant bone tumors.

BACKGROUND
Vascular endothelial growth factor (VEGF) is recognized as an important stimulator of angiogenesis. Formation of new blood vessels by angiogenic factors occurs in many biological processes, both physiological and pathological, among others in growth of primary solid malignant tumors and metastasis. This implies that the inhibition of angiogenic factors like VEGF would result in a suppression of tumor growth and metastasis formation. The aim of the present study was to compare preoperative serum VEGF levels of patients having malignant bone tumors with healthy controls to identify serum VEGF levels as a tumor marker.


PROCEDURE
Blood sera from patients with high-grade osteosarcoma (n = 17), chondrosarcoma (n = 4) and Ewing sarcoma (n = 6) were taken at the time of diagnosis before biopsy and compared with sera from 129 healthy persons. To measure VEGF levels in serum, a commercially available ELISA was used (Quantikine Human VEGF Immunoassay; R&D Systems).


RESULTS
The observed geometric mean VEGF levels and 95% confidence intervals are 232.0 pg ml(-1) (168.9-318.5) for patients with high-grade osteosarcoma, 325.5 pg ml(-1) (169.3-625.8) for patients with chondrosarcoma, 484.3 pg ml(-1) (284.0-826.0) for patients with Ewing sarcoma, as compared to 216.2 pg ml(-1) (192.8-242.5) for healthy individuals.


CONCLUSIONS
While the sample means for the three groups of sarcoma patients were higher than the respective mean for the healthy controls, only the mean for the group with Ewing sarcoma is statistically significantly higher than the mean for the healthy controls. Despite the significant difference, VEGF levels are not suitable as a marker for Ewing sarcoma.