Brain Tumor Facts and Stats


According to the American Brain Tumor Association, brain tumors are the:

  • Second leading cause of cancer-related deaths in children (males and females) under age 20 (leukemia is the first).
  • Second leading cause of cancer-related deaths in males ages 20-39 (leukemia is the first).
  • Fifth leading cause of cancer-related deaths in females ages 20-39.
  • For every 100,000 people in the United States, approximately 221 are living following the diagnosis of a brain tumor.
  • Every day, 500 people hear the words, “It’s a brain tumor.”
  • There are 120 types of brain tumors.  The most common brain tumor to occur is the metastatic brain tumor.


Common Benign Brain Tumors: 

Even though a tumor may be categorized as ‘benign,’ it does not mean it is harmless to a patient. Benign brain tumors can still be life threatening for patients.


  • A meningioma is a usually benign, slow growing, primary brain tumor arising from the meninges, the ‘coverings’ of the brain. Meningiomas can occur anywhere along the meninges, but are more frequently found along the top and outer curve of the brain or at the skull base.
  • Meningiomas represent approximately 20% to one third of all primary brain tumors.
  •  Women are about twice as likely to develop these tumors versus men with diagnosis most often occurring at middle age. Research suggests incidence of these tumors appears to increase with age.
  • Though they do not typically invade surrounding brain tissue, their growth causes additional pressure on the brain. Meningiomas can also contain cysts (fluid), calcifications, or bunches of blood vessels. Some meningiomas can be or become malignant in terms of invasiveness and growth rate.
  • It is estimated that roughly 90 people in the Jacksonville area are diagnosed with this tumor each year.
  • Over 90,000 meningiomas have been treated with Gamma Knife worldwide.

Clinical Data:

  • According to clinical research, approximately 93-98% of patients experience long-term tumor control of 5-10 years defined at tumor shrinkage or no further growth for small tumors of 3-3.5 cm or less.
  • Clinical data also supports that the control rate after Gamma Knife is equivalent to surgical resection for Simpson Grade 1 tumors and superior to Grade 2 and 3-4 resections.
  • Gamma Knife can be used in combination with surgery for larger tumors and is effective at treating residual or recurrent tumor tissue.

Acoustic Neuroma:

  • Also called a vestibular schwannoma, an acoustic neuroma is a benign, slow growing, primary brain tumor located on or around the 8th cranial or ‘hearing and balance’ nerve.  These tumors usually form along the area of the nerve as it leaves the brain stem and goes into the inner ear.
  • Acoustic neuromas represent about 8% of all primary brain tumors. These tumors typically occur in adults, particularly in their middle years of life.
  • Women are twice as likely to develop this tumor as men.
  • It is estimated that roughly 38 people in the Jacksonville area are diagnosed with this tumor each year.
  • Over 63,000 of these tumors have been treated with Gamma Knife worldwide.

Clinical Data:

  • Clinical research reports long-term tumor control rates (5-15 years) of 93-100% for tumors 3 cm or less.
  • Useful pre-radiosurgery hearing can be preserved in approximately 60-90% of patients.
  • For patients with intracanalicular tumors, useful pre-treatment hearing can be preserved in about 73-100%.
  • Research also supports greater than 95% of patients have preserved facial and trigeminal nerve function after treatment.

Pituitary Adenoma:

  • A pituitary adenoma is a typically benign, slow growing tumor of the pituitary gland. In rare cases, these tumors can be malignant, and then are usually referred to as pituitary carcinomas.
  • Pituitary adenomas can be either “secreting” or “non-secreting” tumors.
  • Secreting tumors cause the gland to produce an excessive amount of hormones typically controlled by the gland, and the majority of pituitary adenomas fall into this category. Secreting tumors are then further broken down into the type of excessive hormone produced.
  • Most pituitary adenomas grow in the front area of the gland.
  • Pituitary adenomas represent about 10-13% of all primary brain tumors.
  • These tumors can occur at any age, but tend to be more common in adults.
  • Secreting tumors tend to occur in those younger in age.
  • Women are more likely to be affected by these tumors than men, particularly during childbearing years.
  • It is estimated that roughly 47 people in the Jacksonville area are diagnosed with this tumor each year.
  • Over 50,000 cases have been treated with Gamma Knife worldwide.
  • Gamma Knife is typically used for the treatment of residual or recurrent tumors following surgery, but can be used for primary treatment if surgery is deemed inadvisable.

Clinical Data:

  • Clinical research supports tumor control rates for both secreting and non-secreting tumors to be between 70-90%.
  • For secretory tumors, research supports approximately 50-60% of cases will achieve endocrine control in 12-60 months after treatment.

Malignant Brain Tumors

Metastatic Brain Tumors:

  • Also referred to as a brain metastasis or secondary brain tumor, a brain metastasis is a brain tumor that develops when cancer cells from a primary cancer elsewhere in the body spread and form an new tumor site in the brain.  A ‘metastasis’ refers to single tumor, whereas ‘metastases’ refer to multiple tumors.
  • Metastatic brain tumors are the most common brain tumors to occur in adults.
  • Though the exact instance of these tumors is unknown, it is estimated that 20-40% of patients with a cancer diagnosis may develop metastatic brain disease at some point during the course of their primary disease.
  • Cancers of the lung, breast, skin (melanoma), colon, and kidneys are the most common cancers to spread to the brain. Lung and colon cancer are more likely to produce multiple tumors. Melanoma and renal cell carcinoma are known to be more resistant to radiation treatment.
  • It is estimated that roughly 1,366 people in the Jacksonville area are diagnosed with single or multiple tumors each year.
  • Over 252,400 cases of single and multiple brain metastases have been treated with Gamma Knife worldwide.
  • Gamma Knife treatment can be used as a primary treatment method or in combination with surgery, other forms of radiation therapy, and chemotherapy.

Clinical Data:

  • Gamma Knife treatment of metastatic brain tumors is usually highly effective. Clinical research has shown local control provided by Gamma Knife treatment of brain metastases in any brain location generally exceeds 85%.
  • Typically reserved for tumors that are less than 4 cm in size, the Gamma Knife can treat single or multiple brain metastases in a single outpatient treatment session.
  • Gamma Knife treatment may not impede or interrupt ongoing chemotherapy for treatment of primary disease.
  • Recent clinical studies have found that the presence of active extracranial disease has become the most important prognostic factor for survival, not the presence of brain metastases (CNS disease).

Malignant Glial Brain Tumors:

  • A malignant glial brain tumor is a fast growing, invasive tumor that develops from the different glial cells of brain tissue. 
  • These tumors typically lack distinctive boarders, and invade neighboring healthy brain tissue as they grow.
  • Though these tumors rarely spread to other areas of the body, they can spread to other more distant areas of the brain (or spinal cord) through the cerebrospinal fluid.
  • There are many different types of malignant glial tumors such as astrocytoma, oligodendroglioma, and glioblastoma.
  • It is estimated that roughly 139 people in the Jacksonville area are diagnosed with a malignant glial brain tumor each year.
  • Though not typically a front line therapy for these tumors, the Gamma Knife Perfexion can be used to treat these tumors as part of an overall treatment plan that also includes surgery, chemotherapy, and/or other forms of radiation therapy.
    • Over 30,800 malignant glial brain tumors have been treated with Gamma Knife worldwide.

Clinical Data:

  • While a large series of patients still needs to be reported, preliminary data from neurosurgical and radiation oncology literature indicates that Gamma Knife may have a useful role in the treatment of these tumors.
  • For astrocytoma patients, clinical research shows adding Gamma Knife to other treatments helped approximately 52% of patients gain tumor control at a median of 65 months.
  • Recent clinical research on glioblastoma (glioblastoma multiforme or GBM) suggests that Gamma Knife treatment at the time of tumor progression may lead to longer overall survival.