Angiogenesis in primary central nervous system lymphoma (PCNSL).

Angiogenesis and angiogenic growth factors have a major role in the pathogenesis of malignancies. However, very little is known about the clinical and histopathological relevance of angiogenesis in primary central nervous system lymphoma (PCNSL). We investigated that expression of vascular endothelial growth factor (VEGF) of the lymphoma cells and microvessel density (MVD) were examined in 19 patients with PCNSL. Additionally, the presence of the blood-brain barrier (BBB) was examined using immunohistochemistry and the electron microscopy. MVD was significantly higher in nine cases with VEGF immunoreactivity (VEGF+) than in ten cases with negative immunoreactivity for VEGF (VEGF-) (P < 0.001). VEGF expression was significantly associated with a longer survival (P < 0.005). BBB markers were negative in angiogenic vessels of VEGF+. BBB markers were identified in vessels surrounding tumor cells and tight junctions were also preserved in the capillary endothelium surrounding tumor cells in VEGF-. Angiogenesis is associated with VEGF expression and an absent BBB in the vessels of PCNSL. The BBB may be preserved in lesions with lymphoma cell infiltration, especially in VEGF- PCNSL. VEGF may have a prognostic effect in PCNSL.