Angiogenesis in craniopharyngiomas: Microvascular density and tissue expression of the vascular endothelial growth factor (VEGF) and endostatin

Craniopharyngiomas are benign tumors of the sellar region generally associated with endocrine abnormality and often locally aggressive. Several studies have demonstrated that angiogenesis or neovascularization plays an important role in tumoral growth. The microvascular density (MVD) of craniopharyngiomas was determined in tumor tissue samples from a reference neurosurgery center located in southern Brazil using immunohistochemical methods for two endothelial markers, CD34 and CD105 (endoglin). In addition, tissue expression was determined for an angiogenesis stimulatory factor and for one of its inhibitors, the vascular endothelial growth factor (VEGF) and endostatin, respectively. Endothelial cell immunoreactivity for CD34 and CD105 was observed scattered within the stroma. MVD determined using CD105 antigen was significantly lower than the results obtained by using CD34 antigen. There was no association between the two endothelial markers and tumor extension. The epithelial component showed different degrees of immunoreactivity for VEGF and endostatin in all samples analyzed. We were not able to establish a relationship between angiogenesis in craniopharyngiomas and tumor extension with the endothelial markers used in this study. The investigated vascularization stimulatory and inhibitory factors showed no relation with MVD. We believe that CD105 antigen can be a more specific endothelial marker for tumor angiogenesis than CD34 antigen.