About 6 in every 100,000 individuals in the United States have a meningioma, according to the American Society of Clinical Oncology.
A meningioma is a type of brain tumor found in the meninges, which are the tissues that cover the spinal cord and brain.
It is a primary brain tumor, meaning that the tumor begins in the brain rather than elsewhere in the body. The American Society of Clinical Oncology noted that 34 percent of primary brain tumors are meningiomas.
Meningiomas commonly present in individuals between the ages of 40 and 70. While men and women can both have meningiomas, the brain tumor is more common among women.
The female to male ratio of brain meningiomas is 3 to 1, and the ratio of spinal cord meningiomas is 6 to 1, according to Brigham and Women’s Hospital.
Brigham and Women’s Hospital stated that 90 percent of meningiomas are benign. Even if the tumor is not cancerous, it can still cause impairments.
Individuals with a meningioma may have changes in their vision, such as blurriness or hearing loss. Worsening headaches, weakness in the limbs, and memory loss may occur. Some individuals may have seizures.
Several risk factors have been identified with meningiomas. For example, an individual who has had radiation therapy that targeted the head may have an increased risk of developing a meningioma, according to MayoClinic.com.
Another risk factor for meningiomas is genetic abnormalities, such as neurofibromatosis type 2 (Nf2). Caused by mutations to the NF2 gene, Nf2 results in noncancerous tumors found in the nervous system.
About 1 in 25,000 people have Nf2, according to Genetics Home Reference. Many individuals who have malignant, or cancerous, meningiomas have Nf2.
Brigham and Women’s Hospital explained that a possible reason Nf2 is a risk factor for meningiomas is that individuals with the disorder “have inherited a gene which has the potential to cause normal cells to become cancerous.”
Research has looked at other possible genetics links in meningiomas. A new study conducted at Yale has identified four new genetic links.
The study involved genomic analyses of 300 meningiomas, according to a news release from Yale University, and found mutations of the genes SMO, AKT1, KLF4 and TRAF7.
Two of the genetic mutations, AKT1 and SMO, have previously been linked to other types of cancer.
The news release from Yale University noted that in about 25 percent of the meningiomas in the study, mutations in the TRAF7 gene were noted. Tumors with these mutations were unlikely to become malignant and were discovered in the base of the skull.
The findings from this study can be helpful in determining personalized treatment for individuals with meningiomas, such as targeted chemotherapy.
References:
American Society of Clinical Oncology. Meningioma. Web. 30 January 2013.
http://www.cancer.net/cancer-types/meningioma/statistics
MayoClinic.com. Meningioma. Web. 30 January 2013.
http://www.mayoclinic.com/health/meningioma/DS00901/METHOD=print
Genetics Home Reference. Neurofibromatosis Type 2. Web. 30 January 2013.
http://ghr.nlm.nih.gov/condition/neurofibromatosis-type-2
Brigham and Women’s Hospital. Facts about Meningiomas. Web. 30 January 2013.
http://www.brighamandwomens.org/departments_and_services/neurosurgery/meningioma/meningiomafacts.aspx
Yale News. Genetic Landscape of Common Brain Tumors Holds Key to Personalized Treatment. Web. 30 January 2013.
http://news.yale.edu/2013/01/24/genetic-landscape-common-brain-tumors-holds-key-personalized-treatment
Reviewed January 30, 2013
by Michele Blacksberg RN
Edited by Jody Smith