Prognostic value of vascularity and vascular endothelial growth factor expression in non-small cell lung cancer

High expression of the angiogenic factor vascular endothelial growth factor (VEGF) in tumours has been found to be associated with poor prognosis in some studies, but not in others. The aims of this study were to determine the prognostic value of VEGF in operable non-small cell lung cancer (NSCLC) and its possible association with vascularity.

Sections from 81 NSCLC archival specimens were stained with antibodies to von Willebrand factor (vWF) and VEGF. Vascularity was measured by the average density of vWF positive vessels. VEGF expression in tumour cells was assessed by consensus of two independent observers according to three indices, namely: (1) percentage of area stained, (2) intensity of staining, and (3) final score (product of area and intensity).

VEGF immunoreactivity was present in all tumours and adjacent normal lung tissue. None of the three VEGF indices was associated with vascularity or the clinical parameters examined. Mean survival times were shorter in patients with high VEGF expression, but the difference was not significant. This applied to the full cohort of patients, or when analysed separately according to tumour type or stage. However, high VEGF expression was associated with poor survival in patients with high vascularity (p = 0.02). VEGF had no discriminant value among patients with low vascularity. Vascularity had no prognostic value, except for late stage patients (UICC stages II and IIIa combined; n = 36), where high vascularity was associated with longer survival (p = 0.01).

VEGF on its own has no prognostic value in NSCLC, but may become a useful indicator when combined with vascularity. VEGF may play a physiological role in the normal lung.