Brian A. Neff, M.D.
Brian A. Neff, M.D.
Vestibular schwannomas are the most common cerebellopontine angle tumor evaluated by neurotologists. Patients with these tumors usually present with sensorineural hearing loss, ringing in the ear (tinnitus), and imbalance. There is also a subset of vestibular schwannoma patients that have neurofibromatosis type 2 (NF2), a genetically inherited syndrome which predisposes to bilateral tumors. The tumors arise from the covering of the balance nerves as they enter the ear. Prior to the development of treatment, these benign tumors often grew large enough to cause brain compression and death.
Current treatment options include surgical removal of the tumor or stereotactic (focused) radiation treatments to halt tumor growth. Results of intervention reported in the literature vary widely and are limited by retrospective methodology. The morbidity associated with treatment of these tumors is significant. In those patients who have not already lost their hearing, hearing preservation is possible in 30 percent to 60 percent of patients. Post-treatment facial paralysis can occur, which requires additional surgical procedures to protect from eye irritation and to improve facial appearance. Dizziness, imbalance, and tinnitus are frequently present after surgery or radiation. These post-treatment morbidities are magnified in cases of NF2-associated bilateral schwannomas in which patients can be left with bilateral deafness, facial paralysis, and a permanent imbalance.
Currently, there are no medical or targeted therapeutics that can halt the growth of these tumors in cell culture, animal models, or human studies. There is a great clinical need to improve on our current treatment standards. This will only come about through delivering new treatment strategies aimed at blocking specific steps in the development of these tumors or altering current treatment modalities to improve clinical outcomes in these patients. It is not expected that such a therapy would supplant surgery or radiation treatment in favorable (small) tumors in healthy individuals. However, use of such a therapy in initial clinical trials would be aimed at NF2 patients with multiple tumors that may not respond as well to surgery or radiation therapy. Eventually, if efficacy is established, patients with very large sporadic tumors may benefit from such a therapy to shrink tumors prior to removal. This may alleviate some postoperative complications which we know occur more frequently with surgical removal of larger tumors.
The focus of our laboratory work is to evaluate the effectiveness of targeted inhibitors of vestibular schwannoma development. Additionally, we are evaluating novel immunotherapy approaches that may lend themselves to improving treatment of these tumors in NF2 patients.
BA 5/93-Summa Cum Laude Graduate
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