A mixed brain tumor is explained by a neurosurgeon who treats all kinds of brain tumors.
This common term in neurology refers to a type of malignant mass that is composed of more than one type of cell.
The type of cell is called a glial cell.
Certainly you’ve heard of neurons. You probably know that neurons conduct “nerve impulses.”
There are sensory and motor neurons. They are messengers in the nervous system.
But the nervous system also needs support staff.
These are the glial cells, and they do not conduct signals. But they do surround the neurons to give them support and insulation.
When it comes to malignant brain tumors that are blended, at least one of three types of glial cells is involved.
I. Astrocyte → astrocytoma (including glioblastomas)
II. Oligodendrocyte → oligodendrogliomas
III. Ependymal cells → ependymomas
“Mixed brain tumors are a controversial diagnosis,” says Sumeer Sathi, MD, a neurosurgeon who treats brain tumors, and founding member of Long Island Neuroscience Specialists.
“WHO in 2016 recommended designating them based on genetic screening or markers of the tumor.
“For example, oligodendrogliomas have chromosome deletion of 1p/9q and IDH (isocitrate dehydrogenase) mutations, and astrocytomas are characterized by overexpression of p53, etc.
“Most of these tumors based on these criteria turn out to be grade II oligodendrogliomas.”
Treatment for a Mixed Brain Tumor
“Treatment is based on the diagnosis, based on these genetic studies,” says Dr. Sathi.
“Generally for both, surgery, radiation and chemotherapy are used for these tumors.
“For oligodendrogliomas, chemotherapy options include use of procarbazine, lomustine and vincristine.
“Clinical trials with telazolamide are ongoing for oligodendrogliomas which is used routinely for high grade astrocytomas.”
A mixed or blended brain tumor is rare among brain tumors overall.