Patterns of expression and secretion of vascular endothelial growth factorin malignant soft tissue tumours

Vascular endothelial growth factor (VEGF) is an important cytokine especial ly in the process of tumour angiogenesis. A total of 46 soft-tissue sarcoma s were analysed for the expression and possible secretion of VEGF by immuno histochemistry, in-situ hybridisation, and enzyme-linked immunosorbent assa ys (ELISA). VEGF was demonstrated immunohistochemically in tumour tissue in 45 of 46 cases. The detection of mRNA transcripts yielded evidence of synt hesis of VEGF in these sarcomas. ELISA could be performed in 21 cases. High er concentrations of VEGF were found in tumour-related intraoperatively sam pled venous blood in 16 out of 21 patients (76%) than in systemic concentra tions taken preoperatively. The results indicated the secretion of VEGF by tumour cells although these raised concentrations were not statistically si gnificant. In 12 out of these 16 patients (75%) a concurrent moderate to st rong immunoexpression of VEGF was detected. The relevance of VEGF blood con centrations as a potential "progress parameter" for the course of disease r emains questionable. This is mainly due to the lack of statistical signific ance in the difference between systemic VEGF concentrations in patients and those of a control group. Further long-term follow-up studies are needed, which should include patients with tumour recurrences.