Schwannoma in the leg
Benign tumors can occur in nerves, muscle and bone. This illustration shows a schwannoma of the tibial nerve in the leg.
A more complex nerve sheath tumor may assume the shape of a dumbbell. These occur in the spine and pelvis and are intertwined with important nerves.
Acoustic neuroma (vestibular schwannoma)
An acoustic neuroma (vestibular schwannoma) is a benign tumor that develops on the balance and hearing nerves leading from your inner ear to the brain. These nerves are twined together to form the vestibulocochlear nerve (eighth cranial nerve). The pressure on the nerve from the tumor may cause hearing loss and imbalance.
Peripheral nerve tumors are growths in or near the strands of tissue (nerves) that transmit signals from your brain to the rest of your body. These nerves control your muscles so that you can walk, blink, swallow, pick things up and do other activities.
Peripheral nerve tumors can occur anywhere in the body. Most of them aren't cancerous (malignant), but they can lead to pain, nerve damage and loss of function in the affected area.
Treatment of peripheral nerve tumors usually involves surgery to remove the tumor. Sometimes the tumor can't be removed without damaging nearby healthy tissue and nerves. In these cases, other treatments may be recommended.
Several types of peripheral nerve tumors occur. These tumors affect nerves by growing within them (intraneural tumors) or by pressing against them (extraneural tumors).
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The symptoms and signs of a peripheral nerve tumor develop from direct effects on the main nerve or from the tumor pressing on nearby nerves, blood vessels or tissues. As the tumor grows, it may be more likely to cause signs and symptoms, although tumor size doesn't always determine effects.
Signs and symptoms of peripheral nerve tumors vary depending on the location of the tumors and which tissues are affected. They include:
- Swelling or a lump under your skin
- Pain, tingling or numbness
- Weakness or loss of function in the affected area
- Dizziness or loss of balance
When to see a doctor
See your doctor when you have any of the symptoms listed, especially if you have a lump that grows rapidly.
The spinal cord is housed within a hollow chamber within the vertebrae (spinal canal). It extends from the base of the skull to the lower back.
It's not clear why most peripheral nerve tumors develop. Some are linked to known inherited syndromes, such as neurofibromatosis (types 1 and 2) and schwannomatosis. Others may be caused by a malfunctioning gene or triggered by injury or surgery.
Peripheral nerve tumors are more common in people who have:
- Neurofibromatosis (types 1 and 2) and schwannomatosis. In these disorders, tumors develop on or near the nerves throughout the body. These tumors, which are frequently multiple, can lead to a variety of symptoms and signs depending on their location. These tumors are usually noncancerous.
- A history of radiation treatment. If you were exposed to radiation, you are at increased risk of peripheral nerve tumors years later.
Both noncancerous and cancerous peripheral nerve tumors can compress nerves, leading to complications, some of which may be permanent:
- Numbness and weakness in the affected area
- Loss of function in the affected area
- Difficulties with balance
Peripheral nerve tumors care at Mayo Clinic
May 17, 2019
- Gilchrist JM, et al. Peripheral nerve tumors. http://www.uptodate.com/home. Accessed Oct. 28, 2016.
- Montano N, et al. Tumors of the peripheral nervous system: Analysis of prognostic factors in a series with long-term follow-up and review of the literature. Journal of Neurosurgery. 2016;125:363.
- Riggin ER. Allscripts EPSi. Mayo Clinic, Rochester, Minn. Oct. 28, 2016.
- Overview of peripheral nervous system disorders. Merck Manual Professional Version. https://www.merckmanuals.com/professional/neurologic-disorders/peripheral-nervous-system-and-motor-unit-disorders/overview-of-peripheral-nervous-system-disorders. Accessed March 1, 2017.
- Ahlawat S, et al. Magnetic resonance neurography of peripheral nerve tumors and tumorlike conditions. Neuroimaging Clinics of North America. 2014;24:171.
- Klein CJ, et al. Genomic analysis reveals frequent TRAF7 mutations in intraneural perineuriomas. Annals of Neurology. 2017;81:316.
- Amrami KK, et al. Introduction: Imaging of peripheral nerves. Neurosurgical Focus. 2015;39:E1. http://thejns.org/doi/pdf/10.3171/2015.6.FOCUS15314. Accessed April 8, 2017.
- Spinner RJ, et al. The unifying articular (synovial) origin of intraneural ganglia: Evolution-revelation-revolution. Neurosurgery. 2009;65:A115.
- Capek S, et al. Perineural spread of pelvic malignancies to the lumbosacral plexus and beyond; Clinical and imaging patterns. Neurosurgical Focus. 2015;39:E14.
- Carlson ML, et al. Facial nerve schwannomas: Review of 80 cases over 25 years at Mayo Clinic. Mayo Clinic Proceedings. 2016;91:1563.
- Ducatman BS, et al. Malignant peripheral nerve sheath tumors: A clinicopathologic study of 120 cases. Cancer. 1986;57:2006.
- Prasad, N, et al. Clinical anatomy leading the way for solutions: An important paradigm for translational research. Clinical Anatomy. 2016;29:978.
- Broski SM, et al. Evaluation of 18-F-FDG PET and MRi in differentiating benign and malignant peripheral nerve sheath tumors. Skelatal Radiology. 2016;45:1097.
- Babovic-Vuksanovic D, et al. Multiple orbital neurofibromas, painful peripheral nerve tumors, distinctive face and marfanoid habitus: A new syndrome. European Journal of Human Genetics. 2012;20:618.
- Radiation injury to the brain. International RadioSurgery Association. http://www.irsa.org/radiation_injury.html. Accessed April 11, 2017.
- Pope TL. Soft tissue tumors. In: Musculoskeletal Imaging. Philadelphia, Pa.: Saunders Elsevier; 2015. https://www.clinicalkey.com. Accessed April 10, 2017.
- Goldblum JR, et al., eds. Benign tumors of peripheral nerves. In: Enzinger and Weiss's Soft Tissue Tumors. 6th ed. Philadelphia, Pa.: Saunders Elsevier; 2014. https://www.clinicalkey.com. Accessed April 10, 2017.
- Koht A, et al. Neuromonitoring in surgery and anesthesia. http://www.uptodate.com/home. Accessed April 11, 2017.
- Wise SC, et al. Surgical salvage of recurrent vestibular schwannoma following prior stereotactic radiosurgery. Laryngoscope. 2016;126:2580.
- Stucky CCH, et al. Malignant peripheral nerve sheath tumors (MPNST): The Mayo Clinic experience. Annals of Surgical Oncology. 2012;19:878.
- Spinner RJ (expert opinion). Mayo Clinic, Rochester, Minn. May 28, 2017.
- Stereotactic radiosurgery overview. International RadioSurgery Association. http://www.irsa.org/radiosurgery.html. Accessed April 11, 2017.
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