Markers of angiogenesis (CD31, CD34, rCBV) and their prognostic value in low-grade gliomas

Background and purpose: Antigens CD31 and CD34 and relative cerebral blood volume (rCBV) in gliomas reflect in different ways neoangiogenesis of the tumour. Thus, we decided: (1) to estimate the correlation between the values of CD31 and CD34 and the value of rCBV in low-grade gliomas (LGG), and (2) to establish the prognostic value of these markers. Material and methods: The investigated group consisted of 53 patients with LGG who were operated on in the Neurosurgical Department at Sosnowiec between 2005 and 2011. On the basis of perfusion-weighted imaging (PWI-MRI) in the tumour texture, rCBV was calculated. The values of CD31 and CD34 were estimated on the basis of immunohistochemical investigation. Three outcome measures were assessed: (1) overall survival, (2) progression-free survival, and (3) malignant-free survival. Statistical analyses were done using the STATISTICA 9.0 program. Results: Higher value of rCBV in the texture of LGG significantly correlated with higher CD31 (p = 0.0006) and CD34 values (p = 0.0043). Progression-free survival was significantly longer in patients with rCBV < 1.75 than for persons with rCBV > 1.75 (p = 0.015). Lower expression of CD31 correlated with probability of longer survival of the patients after the operation of LGG (p = 0.068). Conclusions: Density of microvessels as assessed immunohistochemically with CD31+ and CD34+ in LGG correlated with the value of rCBV in the tumour. The value of 1.75 for rCBV may be the threshold for better or poorer outcome of these patients. Expression of CD31 antigen is an important prognostic factor for the time of survival for patients with LGG.