Meningiomas are relatively common tumors occurring around the brain and spinal cord, which are usually benign and found most frequently in older women. A link between meningiomas and female hormones, particularly progesterone, has been suggested based on clinical observation. Studies to date have supported the possibility of a weak link between this tumor and hormone therapy.
Meningiomas
Meningiomas are predominantly benign, or non-cancerous, tumors that arise from the fibrous membranes that surround the brain and spinal cord, according to MayoClinic.com. Symptoms often develop slowly, and can vary depending on the size and location of the tumor. Common complaints include changes in vision, headaches, hearing loss and seizures. Although many meningiomas may be small and asymptomatic, malignant meningiomas can occur.
Risk Factors
Meningiomas occur most commonly between the ages of 40 and 70, and are roughly three times more common in women than men, according to the Brain Science Foundation. Recognized risk factors for developing a meningioma are radiation exposure, female hormones and a rare genetic disorder called neurofibromatosis type 2. Other suggested risk factors such as previous trauma, viruses and cell phone use have not been proven.
Links with Progesterone
Several pieces of evidence support a link between progesterone and the development of meningioma, as reported by Blitshteyn, Crook and Jaeckle in the Jan. 10, 2008, issue of the "Journal of Clinical Oncology." The increased incidence of meningioma in women, an association with breast cancer and tumor growth during pregnancy or menstruation has all been clinically recognized. Special studies have shown 70 percent or more of meningiomas to have progesterone receptors on their cell surfaces, implying the ability to recognize and respond to progesterone. Meningioma cells grown in cultures have also been observed to multiply when exposed to progesterone.
Hormone Therapy
Medical studies have been performed attempting to demonstrate a link between meningiomas and hormone replacement therapy or oral contraceptives, including the analysis done by Blitshteyn et al. Their statistical study found approximately a two-times increased risk of meningioma in women receiving hormone replacement therapy, or about a 0.5 percent increase in absolute risk. The conclusion was hormone replacement therapy may be a risk factor for meningioma. Other studies have shown little or no increased risk.
Treatment of Meningioma
Some meningiomas remain small and cause no symptoms, and can be followed without removal or other treatment. Those that are larger or create problems are usually removed surgically, but may require radiation therapy in certain circumstances. There is currently no established role for the use of hormones or hormone blockers in the treatment of meningiomas, according to the Brain Science Foundation.
