Vascular endothelial growth factor (VEGF) and microvessel density in squamous cell carcinomas of the larynx: an immunohistochemical study

The distribution of vascular endothelial growth factor (VEGF), one of the m ost important angiogenic factors, and microvessel density (MVD) were assess ed in laryngeal carcinomas by means of immunohistochemistry. Correlation of VEGF with MVD and clinical parameters (T stage, N stage, histological grad ing, survival, recurrence-free interval) was also examined. VEGF expression was evaluated semi-quantitatively and was observed in varying intensity (i ) in tumour cells, (ii) in the stromal department as diffuse, sometimes str ong reactivity, especially in close proximity Id tumour masses and (iii) in macrophages and endothelial cells. Normal epithelium presented no VEGF rea ctivity except in the immediate vicinity of tumour transformation. Forty pe rcent of our specimens exhibited substantial VEGF reactivity, whereas 20% s howed no staining in tumour cells and stroma. high-graded carcinomas reveal ed higher VEGF expression, but there was no association of tumour Stage or lymph node status with VEGF or MVD. There was a trend in the survival and r ecurrence analysis towards a higher risk of disease relapse and shorter Sur vival time for patients with enhanced VEGF expression. Apart from tumour ce lls, macrophages seem to be a substantial sourer of VEGF in carcinomas. Thi s observation supports the concept of a pivotal role of these cells in tumo ur defence-in our case, promoting tumour formation by contributing to neova scularization. VEGF was also found in the connective tissue, where it seems to be bound on collagens and probably builds a reservoir for rapid enzymat ic mobilization.