Neoplasms refer to the abnormal growth that can develop in the body which can either be cancerous (malignant) or non-cancerous (benign). The nervous system consists of the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS contains the brain and the spinal cord and the PNS contain the nerves all over the body. The nerve signal is transmitted with the help of nerve fibers that are covered in myelin which is made of the protective substance called the nerve sheath. Sometimes the cells that create the myelin can grow uncontrollably forming a nerve sheath tumor. The two common benign tumors of the nerve sheath include Schwannomas and neurofibromas. The malignant peripheral nerve sheath tumor can be a very aggressive cancerous tumor that can occur in association with neurofibromatosis type 1.
Malignant Peripheral nerve sheath tumor
Also known as neurofibrosarcomas, it develops in the cells that cover the nerves which can occur anywhere in the body and mostly affects the adults. The initial symptom is the presence of a lump or a mass that tends to increase in size causing pain or tingling sensation. This is considered to be an aggressive form of cancer as it mostly has the ability to regrow after surgery and can also spread to other parts of the body particularly the lungs. The earlier it is identified, the better the prognosis. The prognosis is also based on the size of the tumor and the location. Individuals who have the tumor in the limbs have a longer survival than those with the tumor in the head and the neck region. The treatment includes a surgery to remove the tumor, a radiotherapy and chemotherapy.
Schwannomas
These are slow growing benign tumors of the nerve sheath that can push the nerve fibers aside and rarely has the ability to become malignant. This can develop from any peripheral nerve containing the schwannoma cells which commonly occur as solitary tumor but occasionally as multiple lesions. The symptoms of schwannomas are the mild nerve function problems or pain that is caused by the pressure on the surrounding nerve. Schwannomas within the spinal canal can also develop causing compression of the spinal cord resulting in symptoms such as numbness, weakness, stiffness, urine or bowel problems and paralysis. The treatment usually involves the surgical removal of it and their recurrences are rare.
Neurofibroma
Neurofibroma is the benign tumors of peripheral nerves and the common cause of this condition is neurofibromatosis type 2. This tumor commonly affects the vestibulocochlear nerve which is responsible for the transmission of sound and balance information to the brain. The symptoms of this condition are based on the location and the size of the tumor but typically are painless masses causing no symptoms. In the case a motor or sensory nerve becomes affected, it can impair the normal function of the nerve involved.
References
https://sarcoma.org.uk/sarcoma-types/malignant-peripheral-nerve-sheath-tumour-mpnst
https://rarediseases.info.nih.gov/diseases/10872/malignant-peripheral-nerve-sheath-tumor
http://neurosurgery.ucla.edu/schwannomas
http://www.upmc.com/services/neurosurgery/brain/conditions/brain-tumors/pages/neurofibroma.aspx
http://www.neurosurgeonsofnewjersey.com/benign-nerve-sheath-tumor/
