Bilateral vestibular schwannomas are most strongly associated with which genetic disorder?

• A. NF1
• B. MS
• C. NF2
• D. MEN syndrome

Answer: (C)

Bilateral vestibular schwannomas are a hallmark of Neurofibromatosis type 2. This genetic disorder stems from loss-of-function mutations in the NF2 gene, which encodes the tumor suppressor merlin (schwannomin). Without merlin, Schwann cells readily form schwannomas along peripheral nerves, with the eighth cranial nerves being the most characteristically affected, leading to hearing loss, tinnitus, and balance problems. The bilateral involvement of these nerves is highly suggestive of NF2, and patients may also have other CNS tumors such as meningiomas or ependymomas.

In contrast, Neurofibromatosis type 1 typically presents with cutaneous features like café-au-lait spots and multiple cutaneous neurofibromas, not vestibular schwannomas. Multiple sclerosis is a demyelinating disease, not a tumor predisposition syndrome, and MEN syndromes focus on endocrine tumors, not bilateral vestibular schwannomas.