Loss of chromosome 22 and absence of NF2 gene mutation in a case of multiple meningiomas

Multiple meningiomas are rare, and only 13 cases have been subjected to molecular genetic analysis to detect mutations of the tumor-suppressor gene neurofibromatosis type 2 (NF2) located on chromosome 22. Most of these cases display NF2 gene mutations parallel to loss of the chromosome 22 homolog, indicating that inactivation of this gene may represent an early event in the development of multiple meningiomas. We report a case of a 61-year-old woman who developed multiple (dorsal and intracranial) meningiomas. Cytogenetic and molecular genetic studies demonstrated the loss of a copy of chromosome 22 in the 5 meningiomas studied and the absence of NF2 gene mutations in 4 of those available for this molecular analysis. These findings, together with similar data from 2 previously reported cases, suggest the participation of a tumor-suppressor gene other than NF2 on chromosome 22 in the pathogenesis of a subgroup of multiple meningiomas.