Brain Tumors Overview Incidence

When abnormal cells reproduce excessively in the brain, a brain tumor forms. A brain tumor can be considered either cancerous (malignant) or noncancerous (benign).

Brain Tumor Statistics

Brain tumor incidence has been steadily increasing for decades, and researchers aren’t sure why. According to estimates from the American Brain Tumor Association, in the U.S. in 2010:

  • More than 62,000 new cases of primary brain tumors will be diagnosed.
  • Over 39,000 will be benign.
  • Over 23,500 will be malignant.

In addition, more than 150,000 people each year will have symptoms of secondary brain tumors or metastatic brain tumors in the spinal cord.

The risk for developing a brain tumor increases with age, with the lowest incidence rate for children under 20 years old. The rate continues to increase steadily, and peaks from ages 75 to 84. Interestingly, after age 85, risk of developing a brain tumor drops.

In children, brain tumors are the second most common diagnosed malignancy, behind leukemia. The American Brain Tumor Association estimates over 4,000 children under the age of 20 will be diagnosed with a primary brain tumor in 2010.

Sometimes, people have an increased incidence of brain tumors due to inherited factors, including:

  • Li-Fraumeni syndrome
  • Neurofibromatosis
  • Turcot syndrome
  • Von Hippel-Lindau syndrome.

Exposure to vinyl chloride, which is a carcinogen, is one known environmental risk factor for brain tumors. People who work at or live in close vicinity to factories that manufacture plastic products also appear to have an increased risk of developing brain tumors.

Brain Tumor Prevalence

The most common types of primary brain tumors are meningiomas and gliomas. Secondary tumors, however, are far more common than primary tumors, and have an annual incidence rate of over four times that of primary brain tumors.

Some brain tumors are more common in certain groups of people. Meningiomas, for example, are more prevalent in women between 40 and 70 years of age. These are benign tumors, but can be fatal depending on their size and location. Medulloblastomas, on the other hand, are the most common type of malignant brain tumors in children. Brain tumors that originate in lymphocytes are common in HIV/AIDS patients.

Resources

American Brain Tumor Association Staff. (2010). Facts