Y. Yao et al., Prognostic value of vascular endothelial growth factor and its receptors Flt-1 and Flk-1 in astrocytic tumours, ACT NEUROCH, 143(2), 2001, pp. 159-166
Background. Vascular endothelial growth factor (VEGF)/vascular permeability
factor (VPF) is an important regulator of angiogenesis and vascular permea
bility.
Method. We examined immunohistochemically expressions of VEGF and its corre
sponding receptors Flt-1 and Flk-1 in a series of 50 astrocytic tumours, an
d correlated their expressions with the degree of angiogenesis, brain edema
and prognosis.
Findings. There were significant relationships between VEGF, Flk-1 expressi
ons and glioma malignancy grading, intratumoural vascularity and peritumour
al brain edema, respectively. Patients with VEGF positive low grade astrocy
toma and glioblastoma multiforme had a significantly shorter mean overall s
urvival time than those with negative tumours (P = 0.0010 and 0.0180, respe
ctively). Flk-1 is also a significant prognostic factor within each tumour
grade, which has a negative impact on overall survival. Additionally, overe
xpression of VEGF and Flk-1 were significantly associated with earlier recu
rrence in patients with low grade astrocytomas (P = 0.0018 and 0.0240, resp
ectively).
Interpretation. It is possible to subcategorize each grade of astrocytic tu
mours based on their VEGF and Flk-1 staining pattern, which may be crucial
in predicting the biological behavior of tumours and thus provide useful in
formation with regard to adequate treatment.