Skip to main content

Evidence for Genetic Heterogeneity in Neurofibromatosis type 2 Associated Multilobular Vestibular Schwannoma

Friday, November 08, 2013 — Poster Session III

10:00 a.m. – 12:00 p.m.

FAES Academic Center (Upper-Level Terrace)




  • R Dewan
  • A Pemov
  • P Chittiboina
  • X Wang
  • A.R. Asthagiri


Neurofibromatosis type 2 (NF2) is an autosomal dominant tumor predisposition syndrome that results from inactivation of the NF2 tumor suppressor gene on chromosome 22q12. Its most common clinical manifestation is the presence of bilateral vestibular schwannomas. Though NF2-associated and sporadic vestibular schwannomas share identical histopathologic findings and underlying cytogenetic alterations, NF2-associated vestibular schwannomas are less responsive to treatment with radiosurgery and are significantly more likely to recur after surgical resection. Emerging data from temporal bone autopsy specimens and advanced MR-imaging of the inner ear performed in children with NF2 suggest the possibility that multiple discrete microscopic tumors may be present. Additionally, adults with NF2 have vestibular schwannomas that are multilobulated, as opposed to the spherical shape of their sporadic counterparts. Here, we have utilized SNP array analysis and direct sequencing to show that four consecutive multilobulated schwannomas resected from four different patients with NF2 display an admixture of cell populations at the NF2 locus. This data proves that in NF2 patients, multilobulated cerebellopontine angle lesions arise from multiple clones, and the collision of distinct tumors may indeed give rise to their unique gross appearance. These findings may play a significant role in explaining their variable response to conventional therapeutic approaches.

back to top