Neurofibromatosis type 2 (NF 2) or schwannomatosis?--Case report study and diagnostic criteria

Neurofibromatosis type 2 (NF2) and schwannomatosis are entities that may, due to the similarity of clinical symptoms, cause diagnostic difficulties. Incidence rate of both diseases is similar and estimated between 1:25,000 and 1:40,000. The genes associated with the development of the aforementioned disorders are located on chromosome 22 and lay in proxmity. Schwannomatosis is characterized by an incomplete penetrance and the risk of its transmission to the offspring is significantly lower than in the case of NF 2. Schwannomatosis clinical characteristic is similar to the NF2, however vestibular schwannomas are not present. Therefore the imaging studies evaluated by an experienced radiologist play a key role in the diagnostic process.

Forty two-year-old female hospitalized three times because of the tumors of the spinal canal was admitted to the Department of Neurosurgery and Peripheral Nerve Surgery in 2008 because of the cervical pain syndrome with concomitant headache. She was diagnosed with a schwannomatosis, recently distinguished, the third form of neurofibromatosis. MRI imaging revealed craniocervical junction tumor. Suboccipital craniectomy with concomitant C1-C2 laminectomy was done in order to remove the lesion. After the surgery the patient did not present any deficits in neurological examination and was discharged from hospital in good general condition.

The patient was diagnosed with schwannomatosis, recently established neurofibromatosis entity which may resemble NF2 clinically. In patients after the age of 30, in whom we observe multiple schwannomas without the concomitant hearing impairment, the diagnosis of schwannomatosis is very likely.