understanding what is brain tumor terms

What Is a Brain Tumor? Understanding the Facts

At Advanced Neurosurgical Associates, we are frequently asked about brain tumors. Below is a summary explanation to help you to understand a little more about them.

What Is a Brain Tumor?

First of all, what is a tumor? A tumor is a mass of tissue that is formed by an accumulation of abnormal cells. Ordinarily, the cells in your body age, die, and are replaced by new cells. When something disrupts this process, abnormal cells accumulate, and this begins this process of tumor formation. Tumor cells continue to grow and form a mass.

Understanding Brain Tumor Medical Terms

These abnormal cells develop in various ways, which determines the type and characteristics of a brain tumor:

  • Benign – the least aggressive type of brain tumor is often benign. This type of tumor does not contain cancer cells and typically grows slowly. It usually originates from cells within or surrounding the brain, and typically has clear borders that do not spread into other tissue. However, they can still cause health problems.
  • Malignant – these brain tumors contain cancer cells and often do not have clear borders. They are considered to be life-threatening because they grow rapidly and invade surrounding brain tissue.

Tumors are also defined by where they start:

  • Primary brain tumors – start in cells of the brain. Primary brain tumors may spread to other parts of the brain, but rarely to other organs. Primary tumors occur in people of all ages, but they are statistically more frequent in children and older adults.
  • Metastatic or secondary brain tumors – these begin in another part of the body and then spread to the brain. These tumors are more common than primary brain tumors and are named by the location in which they begin, such as lung or breast cancer. Although statistics for brain metastases are not readily available, it is estimated that there are more metastatic than primary malignant tumors per year. Metastatic brain tumors are more common in adults than children.

about brain tumor statistics

Brain Tumor Facts and Statistics

According to the National Brain Tumor Society, below are some of the latest facts and statistics on brain tumors:

  • In 2021, some 85,000 people in the U.S. will be diagnosed with a primary brain tumor.
  • Around 700,000 Americans live with a primary brain tumor. The median age of diagnosis is 60 years.
  • According to the National Brain Tumor Society, approximately 70% of brain tumors are benign and 30% are malignant. Some 60% of brain tumors occur in females and 40% occur in males.
  • The average survival rate is around 75%, although this changes significantly depending on the tumor. For example, the five-year survival rate drops to 36% for malignant brain tumors, and for the common glioblastoma, it is only around 7% with an average 8-month survival period after diagnosis.
  • Brain tumors are the leading cause of solid tumor death in children under the age of 20. They are the leading cause of cancer death in males ages 15-39, and the fourth leading cause of cancer death in females ages 15-39. For 40 years and older, brain tumors are the third-leading cause of cancer death.
  • There are over 120 different types of brain tumors; both malignant and non-malignant can be life-threatening.
  • An average of almost 80% of children will survive a brain tumor, although often with long-term side effects.

About Brain Tumors

Anyone can be diagnosed with a brain tumor—regardless of gender or ethnicity.

Brain tumors are notoriously difficult to treat. While research and science have resulted in success with other types of cancers, brain tumors have had mixed results. According to braintumor.org, between 1998 and 2014, there were 78 investigational brain tumor drugs that entered the clinical trial evaluation process. Seventy-five failed, and only three were approved (one conditionally). That is a 25:1 failure ratio in developing new brain tumor treatments over the past two decades.

There are only a few known risk factors for brain tumors that research has established, otherwise, the cause is unknown:

  • Children who receive radiation to the head have a higher risk of developing a brain tumor than adults.
  • People who have certain rare genetic conditions such as neurofibromatosis or Li-Fraumeni syndrome are at risk.
  • Age is also a risk factor; those over the age of 65 are diagnosed with brain cancer at a rate four times higher than younger people.