A brain tumor is an overgrowth of abnormal cells that form a mass. There are roughly more than 150 different types of tumors that can develop in the brain and central nervous system, but for the purposes of this page, we will focus on malignant (cancerous) brain tumors.
More than 70% of all brain tumors are gliomas, which are tumors that form in the glial cells (cells located in the central and peripheral nervous system that help support neurons). Some brain tumor types that are considered gliomas include astrocytomas, ependymomas, glioblastomas and oligodendrogliomas.
The most common type of glioma, astrocytomas develop in astrocytes, which are star-shaped glial cells that form part of the brain’s supportive tissue. Although astrocytomas can develop in various areas of the brain, they most commonly form in the cerebrum, which helps control thoughts, emotions, learning, speech, reading, writing and muscle function. And while astrocytomas can affect people of all ages, they’re most common in adults, and especially in middle-aged men.
Ependymomas develop when the ependymal cells—which line the ventricular system—undergo a neoplastic transformation.
While astrocytomas are the most common type of glioma, a glioblastoma (formerly known as glioblastoma multiforme) is the most invasive form of this malignancy. Glioblastomas often contain various types of cells—including astrocytes, ependymal cells and oligodendrocytes—and most commonly affect individuals (especially men) between the ages of 50 and 70. When compared to other types of glial tumors, glioblastomas are more likely to grow quickly and spread to other bodily tissues.
Oligodendrogliomas develop in oligodendrocytes, a type of glial cell that produces myelin to insulate nerve fibers.
Other types of brain tumors
Some non-glial brain tumors include gangliogliomas, hemangioblastomas, medulloblastomas, meningiomas, rhabdoid tumors and schwannomas.
Containing both glial cells and neurons, gangliogliomas most commonly develop in young adults. They generally occur in the cerebrum but can affect any portion of the brain or spinal cord.
Hemangioblastomas develop in the blood vessels of the cerebellum, which is located at the back of the brain and is responsible for helping to control balance and muscle function. They most commonly affect people between the ages of 40 and 60 and tend to occur more frequently in men. Hemangioblastomas often grow to be quite large, and many are accompanied by a cyst. With that said, when compared to certain other brain cancer types, hemangioblastomas are considered to be relatively slow growing.
Although medulloblastomas were originally classified as gliomas, the scientific community has now begun to refer to them as primitive neuroectodermal tumors. Medulloblastomas most commonly develop in the cerebellum’s neuroectodermal cells. While medulloblastomas are generally considered to be high-grade tumors, they’re usually quite responsive to chemotherapy and radiation therapy.
Meningiomas develop in the meninges (membranes that are responsible for protecting the brain and the spinal cord). In most cases, meningiomas are benign, but some may be malignant.
Rhabdoid tumors are one of the rarer types of brain cancer. They tend to be very aggressive, quickly spreading through the central nervous system to distant areas of the body, including the kidneys. Although rhabdoid tumors are more common in young children, they can also affect adults.
Schwannomas develop in Schwann cells, which help insulate the nerves. These tumors are typically benign, but in some cases may be malignant.
Primary brain cancer vs. secondary brain cancer
Brain tumors can also be classified by whether they are primary or secondary tumors. Primary brain tumors are ones that initially develop in the brain. Secondary (metastatic) brain tumors, on the other hand, originate in other organs, such as the breast or lung, and then spread to the brain as they advance. This classification is significant because primary and secondary brain tumors are treated differently.
Another way that brain tumors are categorized is by the type of cells they develop in. Primary brain tumors can start in virtually any kind of tissue or cell in the brain. Some brain tumors are composed of mixed cell types.
How malignant brain tumors are treated at Moffitt
Moffitt Cancer Center’s Neuro-Oncology Program treats all types of malignant brain tumors, including metastatic cancer as well as the rarest forms of primary brain cancer. Our multispecialty brain cancer team is comprised of experts in all fields of therapy, allowing us to take a unique, comprehensive approach to treatment. Our patients receive individualized treatment plans that are developed collaboratively by our team, ensuring that all options are considered for the best possible outcome and quality of life.
Treatment plans can vary greatly from patient to patient and are influenced by many factors, such as the type and grade of the tumor, the tumor’s location and size, the patient’s overall health and more. A treatment plan may include surgery, radiation therapy, chemotherapy, immunotherapy, hormone therapy and other biological therapies. Moffitt also has a robust clinical trials program, making some of the most groundbreaking brain cancer treatments accessible to our patients before they are widely available.
For more information about the many types of brain cancer, or to consult with an oncologist specializing in the treatment of malignant brain tumors, call 1-888-663-3488 or submit a new patient registration form online. Moffitt doesn’t require referrals, and because we understand how stressful it can be to wait on a potential brain cancer diagnosis, we’ll put you in touch with a cancer expert as soon as possible.
American Association of Neurological Surgeons: Brain Tumors