Angiogenesis in glioblastoma--analysis of intensity and relations to chosen clinical data.

Microvascular proliferation (MVP) is one of the histopathological hallmarks of glioblastoma (GB). In this study angiogenic potential in GB was analysed according to the morphology of MVP and by assessment of vascular density. The analysis of relations of vascular parameters to chosen clinical features was performed. Tissue samples from 46 GB cases were examined. The clinical data included: patients' age (32-78 years), gender (17 women, 29 men), location (frontal lobe--13, temporal--18, parietal--14, two lobes--1) and tumour size in CT (2-9 cm). Tumour vascularisation was analysed morphologically and quantitatively. Histologically two types of MVP were distinguished: simple and glomeruloid. In vascular hot spots vessel density was assessed on sections immunostained for vWf. Simple type proliferation was found in all cases. Glomeruloid proliferation was found in 33 cases with mean age of patients 59.5 yrs, while in the group without glomeruloids mean age was 48 yrs (statistically significant difference, p < 0.01). Mean vascular density value in examined GB was 150.4 vessels/mm2 (median 141.5; SD--56.4) and younger age was related to higher vascular density (correlation coefficient R = -0.35; p = 0.017). Vascular parameters were related only to the patients' age among the analysed clinical data. The presented results show that morphologically microvascular proliferation is more intense in older GB patients, since higher vascular density is related to younger age. This observation may suggest the diversity of GB angiogenic potential depending on patients' age.