NF2

Neurofibromatosis type 2 (NF2) is a rare autosomal dominant genetic disorder characterized by the growth of tumors on the nervous system, most notably bilateral vestibular schwannomas that arise from the eighth cranial nerves. People with NF2 may also develop meningiomas, schwannomas on other cranial and spinal nerves, ependymal tumors, and various ocular abnormalities. The condition can lead to hearing loss, balance problems, headaches, and other neurological symptoms depending on tumor location.

NF2 results from mutations in the NF2 gene on chromosome 22q12.2, which encodes the tumor suppressor protein merlin (also called schwannomin). Loss of merlin function disrupts cell growth control in Schwann cells, enabling tumor formation. Most cases arise as new (de novo) mutations, though inherited cases occur with autosomal dominant transmission. Affected individuals have a high lifelong risk of developing tumors, and each child of an affected parent has a 50% chance of inheriting the mutation.

Clinical features commonly include progressive, often early-onset hearing loss and tinnitus due to bilateral vestibular schwannomas, imbalance, and headaches. Additional tumors may affect the brain and spinal cord, causing neurological deficits. Cataracts, particularly juvenile posterior subcapsular cataracts, are also common. Skin findings are less prominent than in other forms of neurofibromatosis.

Diagnosis is based on clinical criteria, imaging, and genetic testing. MRI typically reveals bilateral vestibular schwannomas and other CNS tumors; genetic testing can confirm a pathogenic NF2 mutation. Management is multidisciplinary, focusing on surveillance and treatment of tumors (surgery or radiotherapy), symptom management, hearing rehabilitation, and genetic counseling. There is no cure, but continued monitoring aims to optimize function and quality of life.