The neurofibromatoses are genetic disorders that cause tumors to grow in the nervous system. The tumors begin in the supporting cells that make up the nerves and the myelin sheath. These disorders cause tumors to grow on nerves and produce other abnormalities such as skin changes and bone deformities. Although many affected persons inherit the disorder, between 30 and 50 percent of new cases arise spontaneously through mutation in an individual's genes. Once this change has taken place, the mutant gene can be passed on to succeeding generations.
Neurofibromatosis type 1 (NF1) is the most common type of the neurofibromatoses. Changes in skin appearance, tumors, or bone abnormalities occur. Symptoms of NF1, which may be evident at birth and nearly always by the time the child is 10 years old, may include light brown spots on the skin "cafe-au-lait" spots), two or more growths on the iris of the eye, a tumor on the optic nerve, a larger than normal head circumference, and abnormal development of the spine, a skull bone, or the tibia.
Treatment: Surgery is often recommended to remove the tumors. Some NF1 tumors may become cancerous, and treatment may include surgery, radiation, or chemotherapy.
Prognosis: In most cases, symptoms of NF1 are mild, and individuals live normal and productive lives. In some cases, however, NF1 can be severely debilitating and may cause cosmetic and psychological issues.
NF2 is less common and is characterized by slow-growing tumors on the eighth cranial nerves. The tumors cause pressure damage to neighboring nerves. Tumors in the 8th nerve, cataracts at an early age or changes in the retina that may affect vision, other nervous system tumors are manifestations. It often starts in the teen years.
Treatment: MRIs can reveal tumors as small as a few millimeters in diameter, thus allowing early treatment. Surgery to remove tumors completely is one option but may result in hearing loss.
Prognosis: The course of NF2 varies greatly among individuals. In some cases of NF2, the damage to nearby vital structures, such as other cranial nerves and the brain stem, can be life-threatening.
Schwannomatosis is the rarest of the three types and is characterized by the development of multiple schwannomas everywhere in the body except on the vestibular branch of the 8th cranial nerve. The dominant symptom is pain, which develops as a schwannoma enlarges or compresses nerves or adjacent tissue. Some people may develop numbness, tingling, or weakness in the fingers and toes.
Treatment: There is no currently accepted medical treatment or drug for schwanomatosis, but surgical management is often effective. Pain usually subsides when tumors are removed completely.
Prognosis: Most individuals with schwannomatosis have significant pain. In some extreme cases the pain will be severe and disabling.
Oral lesions occur in 60-70% of cases and are characterized by multiple or isolated nodular neurofibromas, which vary in size. Tumors usually involve the tongue although other areas of mucosa may be affected. Enlargement of the fungiform papilla is common. Macroglossia is less common and lesions of the maxilla and mandible are relatively uncommon.
Neurofibromatosis type 1 (NF1) is the most common type of the neurofibromatoses. Changes in skin appearance, tumors, or bone abnormalities occur. Symptoms of NF1, which may be evident at birth and nearly always by the time the child is 10 years old, may include light brown spots on the skin "cafe-au-lait" spots), two or more growths on the iris of the eye, a tumor on the optic nerve, a larger than normal head circumference, and abnormal development of the spine, a skull bone, or the tibia.
Treatment: Surgery is often recommended to remove the tumors. Some NF1 tumors may become cancerous, and treatment may include surgery, radiation, or chemotherapy.
Prognosis: In most cases, symptoms of NF1 are mild, and individuals live normal and productive lives. In some cases, however, NF1 can be severely debilitating and may cause cosmetic and psychological issues.
NF2 is less common and is characterized by slow-growing tumors on the eighth cranial nerves. The tumors cause pressure damage to neighboring nerves. Tumors in the 8th nerve, cataracts at an early age or changes in the retina that may affect vision, other nervous system tumors are manifestations. It often starts in the teen years.
Treatment: MRIs can reveal tumors as small as a few millimeters in diameter, thus allowing early treatment. Surgery to remove tumors completely is one option but may result in hearing loss.
Prognosis: The course of NF2 varies greatly among individuals. In some cases of NF2, the damage to nearby vital structures, such as other cranial nerves and the brain stem, can be life-threatening.
Schwannomatosis is the rarest of the three types and is characterized by the development of multiple schwannomas everywhere in the body except on the vestibular branch of the 8th cranial nerve. The dominant symptom is pain, which develops as a schwannoma enlarges or compresses nerves or adjacent tissue. Some people may develop numbness, tingling, or weakness in the fingers and toes.
Treatment: There is no currently accepted medical treatment or drug for schwanomatosis, but surgical management is often effective. Pain usually subsides when tumors are removed completely.
Prognosis: Most individuals with schwannomatosis have significant pain. In some extreme cases the pain will be severe and disabling.
Oral lesions occur in 60-70% of cases and are characterized by multiple or isolated nodular neurofibromas, which vary in size. Tumors usually involve the tongue although other areas of mucosa may be affected. Enlargement of the fungiform papilla is common. Macroglossia is less common and lesions of the maxilla and mandible are relatively uncommon.
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