NF2 GENE ANALYSIS DISTINGUISHES HEMANGIOPERICYTOMA FROM MENINGIOMA

The histogenesis of dural-based or ''central'' hemangiopericytomas (cH PCs) remains controversial. Some authors consider these tumors variant s of meningiomas while others consider them akin to peripheral hemangi opericytomas (pHPCs). Meningiomas frequently have mutations in the neu rofibromatosis 2 (NF2) gene, providing a molecular marker for meningio mas and other NF2-related tumors. We therefore analyzed the NF2-relate d tumors. We therefor analyzed the NF2 gene in cHPCs, pHPCs, and menin giomas to determine whether cHPCs are more similar at the molecular ge netic level to meningiomas or hPHCs. Using paraffin-embedded archival material from 28 cHPCs (including three primary and recurrent tumors), 10 pHPCs, and 26 meningiomas, we scanned all 17 exons of the NF2 gene and flanking intronic sequences for mutations with single strand conf ormation polymorphism analysis and DNA sequencing. No NF2 mutations we re found in either cHPCs or pHPCs, whereas 355 of meningiomas had NF2 gene alterations (P < 0.001). The NF2 gene mutations in meningiomas we re all truncating mutations, consistent with previous studies. Our fin dings suggest that cHPCs are distinct from meningiomas at the molecula r genetic level and support prior clinico-pathological data that disti nguish these tumor-entities.