Neurofibromatosis type II of the head and neck.

Neurofibromatosis type II (NF-II) has been traditionally referred to as "acoustic" neurofibromatosis and is not known to be genetically distinct from classic von Recklinghausen's disease (NF-I). Neurofibromatosis type II is due to a lesion on chromosome 22q, while von Recklinghausen's neurofibromatosis is from a defect on chromosome 17. The approximate incidence of NF-II is one in 50,000, with bilateral acoustic neuromas occurring in over 90% of those with the abnormal gene. We studied a 17-year-old boy with NF-II who presented with bilateral acoustic neuromas and concomitant primary nasopharyngeal meningioma. Less than 30 nasopharyngeal meningiomas have been documented, and the presence of both tumor types in the same individual is unique in the literature.