Sporadic CNS hemangioblastomatosis, response to sunitinib and secondary polycythemia

Excerpt

Hemangioblastoma (HB) is an uncommon vascular tumor mainly involving the central nervous system (CNS) or the retina [1]. HB may be associated with von Hippel–Lindau disease (VHL) (OMIM 193.300), an autosomal-dominant disorder, or may appear as a sporadic tumor in the absence of other manifestations of VHL disease. Both VHL-related and sporadic HBs involve the inactivation of the VHL gene on 3p25–26. The VHL product is responsible for the proteolytic degradation of the hypoxia inducible factor (HIF) transcriptional complex. The loss of VHL results, therefore, in inappropriate expression of HIF-dependent factors, including vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and erythropoietin, leading to the development of HBs which are benign, non-metastasizing tumors (WHO grade I) characterized by stromal cells with abundant vascular proliferation [1]. …